EFFECT OF WEATHERING AND ALTERATION ON POINT LOAD AND

SLAKE DURABILITY INDICES AND THE CHARACTERIZATION OF THE

DEBRIS FLOW AT THE QUESTA MINE, TAOS COUNTY, NEW MEXICO

 

by

 

Gertrude Fobiah Ayakwah

 

 

 

Submitted in partial fulfillment of the requirements for the

Degree of Master of Science in Mineral Engineering

with Specialization in Geotechnical Engineering

New Mexico Institute of Mining and Technology

Department of Mineral Engineering

Socorro, New Mexico

May, 2009

  ii

This thesis is dedicated to God almighty for seeing me through, to my Mum Agnes Adjeley

Fumey, my dad Emmanuel Okyere-Boakye Ayakwah and my siblings for their prayers and

support during the writing of this work.

Abstract

Point load strength (Is50) and slake durability (ID2) indices provide a measure of the

strength and durability of rock fragments. These are also related to the alteration intensity

and weathering of the materials. Samples were collected from the rock piles, alteration

scars, and debris flows at the Questa mine with the purpose of examining relationships

between Is50 and ID2, mineralogy, chemistry, weathering, hydrothermal alteration, and

other geotechnical parameters. The Is50 from the various rock piles ranges from 0.6-8.2

MPa and the ID2 ranges from 80.9-99.5%. The Is50 and ID2 results from the samples

collected indicate that, the samples from the debris flows are in average stronger (average

Is50= 4.0 MPa and ID2= 98.4%) than the rock-pile samples and that the alteration scar

samples are in average weaker (average Is50 = 2.8 MPa and ID2 = 89.2%) than the rock-

pile samples. However, most of these rocks are strong in terms of their Is50 and ID2.

The debris flows studied are similar to the Questa rock piles in terms of lithology,

slake and point load indices, friction angle and particle size distribution. The profile

studied is not a typical weathered profile. This is because it was observed that there are

no systematic variations in the composition of the samples collected from the profile, and

this indicates that the debris flow was formed by several different flood events with

slightly different sources. The results of the geochemical and geotechnical

characterization indicate that, the samples collected from the debris flow are similar to

each other and do not show signs of decreasing weathering from the top of the profile to

the bottom. The cementation of the debris flow was found to be similar to the ones found

in the rock piles and is formed by oxidation of sulfide minerals producing sulfates and

iron oxides. The debris flows are therefore well cemented, even below the surface.

  ii

Finally, the slake durability measurements of rock pile material collected from the hot

zones were found to be similar to the measurements obtained for other materials in the

Questa area. They also indicated high durability.

  ii

Acknowledgements

 This study owes its success to several people who contributed in various ways. However,

some key personalities require special mention.

My heartfelt gratitude goes to my research supervisors; Dr. Virginia McLemore

and Dr. Ali Fakhimi, for their encouragement, guidance and constructive criticisms which

enabled me to produce this research work on time.

I also thank Chevron Mining Inc. for funding this research work.

I wish to also than the Questa Rock Pile Weathering Stability Project team for

their assistance throughout the sampling and data analysis period of this project.

To Dave Jacobs of Chevron Mining Inc, Ariel Dickens, Kojo Anim, Frederick

Ennin, Samuel Nunoo, Dawn Sweeney, Kelly Donahue and Erin Philips, I say a big thank

you for your help in the laboratory work and data analysis of this work.

I express my profound gratitude to Dr. Navid Mojtabai, my academic advisor who

has been a father and a consular to me since the day I applied for admission to this

honorable institution and also offered a lot of encouragement.

Finally, to Yirrah family in Virginia, Carilli family in Socorro, my aunties Diana,

Edith, Charlotte, Vida in New Jersey for the love, encouragement and their prayers

during hard times in my academic life.

 

  iii

Table of Contents List of Figures ..................................................................................................................... v List of Tables ..................................................................................................................... ix 1.0 INTRODUCTION ................................................................................................. 1 1.1. Background ...........................................................................................................1 1.2 Thesis Overview ...................................................................................................2 1.3 Project Background ...............................................................................................3 1.4 Thesis Objective and Scope ..................................................................................4 1.5 Description of study area ......................................................................................5 1.5.1 Location ..........................................................................................................5 1.5.2 History of Questa Mine ...................................................................................6 1.5.3 Mine Features..................................................................................................8 1.5.4. Mine geology and mineralogy ......................................................................12 1.6 Rock mass and intact rock strength ....................................................................17 1.6.1 Rock durability and slaking ..........................................................................18 2.0 EFFECTS OF WEATHERING AND ALTERATION ON POINT LOAD AND SLAKE DURABILITY INDICES OF QUESTA MINE MATERIALS, NEW MEXICO…... .................................................................................................................... 22 2.1 Introduction .........................................................................................................22 2.2 Alteration and weathering of the Questa rock piles ............................................24 2.3 Field and Analytical Methods .............................................................................29 2.3.1 Sampling .......................................................................................................29 2.3.2 Laboratory Analysis ......................................................................................30 2.4 Results .................................................................................................................38 2.5 Discussion ...........................................................................................................43 2.6 Conclusions .........................................................................................................55 3.0 CHARACTERIZATION OF QUESTA DEBRIS FLOWS ................................. 57 3.1 Introduction .........................................................................................................57 3.2 Definitions...........................................................................................................58 3.3 Background .........................................................................................................60 3.4 Sampling and analytical methods .......................................................................63 3.5 Description of the debris flow profile .................................................................66 3.6 Results .................................................................................................................68 3.7 Discussion ...........................................................................................................70 3.8 CONCLUSIONS.................................................................................................83 4.0 HOT ZONE STRENGTH STUDY ...................................................................... 85 4.1 Introduction .........................................................................................................85 4.2 Background .........................................................................................................86 4.3 Methods...............................................................................................................87 4.4 Results .................................................................................................................88 4.5 Discussion ...........................................................................................................91 4.6 Conclusion ..........................................................................................................94 5.0 CONCLUSIONS AND RECOMMENDATIONS ............................................ 96 5.2 References Cited .................................................................................................98 APPENDIX A TEST RESULTS ............................................................................... 105

  iv

APPENIDX B. SUMMARY RESULTS OF QUESTA MATERIALS USED IN THE STUDY. .......................................................................................................................... 125 APPENIDX C. SUMMARY COMPARISM STATISTICS OF THE STRENGTH and DURABILITYCLASSIFICATION FOR QUESTA MATERIALS. ............................. 197

  v

List of Figures 

Figure 1.1: Location map of the chevron molybdenum mine and vicinities. ......................6 Figure 1.2: Map of chevron mine site showing mine rock piles and mine features. ...........9 Figure 1.3: Conceptual geological model of GHN rock pile, as interpreted from surface mapping, detailed geologic cross-sections, trenches, drill holes, construction method and observations during reclamation of GHN (McLemore et. al., 2008a) ...............................11 Figure 1.4: Geologic map of Questa – Red River Vicinity (Ludington et al., 2004.) .......13 Figure 1.5: Map of the alteration scars at the Questa Mine. The red circles shows where samples were taken from, for point load and slake durability test. ....................................17 Figure 2.1: The point load strength equipment in use (sample under test), showing contact cones, the loading and measuring systems (display gage) and samples to be tested. ........32 Figure 2.2: Typical irregular samples after point load strength test showing their planes of failure……….. ...............................................................................................................33 Figure 2.3: slake durability equipment during usage comprising of the test drums and the motor for rotation. ..............................................................................................................36 Figure 2.4: A typical brushed sample, each piece weighing between 40 to 60 g before the slake durability test is performed. ......................................................................................36 Figure 2.5: A typical sample after slake durability test showing bigger and smaller pieces of rock fragments after the test. .........................................................................................37 Figure 2.6: Histogram plot of point load strength index at the rock piles location (GHN, SSS, SSW, MID and SPR). ................................................................................................42 Figure 2.7: Histogram plot of slake durability index at the rock piles location (GHN, SSS, SSW, MID and SPR). ................................................................................................42 Figure 2.8: Scatter plot of Slake Durability Index and Point Load Index vs. distance from outer edge of GHN rock pile. The weathering intensity was confirmed by petrographic analyses, especially textures, as described by McLemore et al. (2008a). See Figures 1.2 and1.3 for location of trenches and layers in GHN where samples were obtained. Appendix B includes a summary of the description of these samples. ..............................44 Figure 2.9: Point load strength index values for the rock piles, alteration scars and debris flows. The average point load strength index for each location is shown with a red circle. The number of samples for each location and the standard deviation are shown in parentheses. PIT samples are unweathered drill core samples of andesite and rhyolite (Amalia Tuff) of various hydrothermal alteration intensities. See Figure 1.2 for location of rock piles. See Figures 1.2 and 1.3 for location of trenches and geologic units in GHN where samples were obtained. Appendix B summarizes the location and description of these samples. ....................................................................................................................45 Figure 2.10: Slake durability index values for the rock piles, alteration scars, and debris flows. The average slake durability index for each location is shown with a red circle. The number of samples and the standard deviation for each location are shown in parentheses. PIT samples are unweathered drill core samples of andesite and rhyolite (Amalia Tuff) of various hydrothermal alteration intensities. See Figures 1.2. and 1.3 for location of rock piles and location of trenches and geologic units in GHN where samples were obtained. Appendix B summarizes the location and description of these samples. ..46 Figure 2.11: Variation in slake index, point load and alteration (QSP, Propylitic and Argillic) of the Questa rock materials. See Figure 1.2 for location of rock piles where

  vi

samples were obtained. Appendix B summarizes the location and description of these samples……….. .................................................................................................................47 Figure 2.12: Point load strength index values for different lithologies (Amalia, Andesite and Intrusive) which includes drill core and outcrop samples. The average point load strength index for each lithology is shown with a red circle. The number of the samples and the standard deviation are shown in the parentheses. See Figure 1.2 for location of open pit. Appendix B summarizes the location and description of these samples. ...........48 Figure 2.13: Slake durability index values for different lithologies (Amalia, Andesite and Intrusive) which include the drill core and outcrop samples. The average slake durability index for each lithology is shown with a red circle. The number of samples for each location and standard deviation are shown in the parentheses. See Figure 1.2 for location of open pit. Appendix B summarizes the location and description of these samples. ......48 Figure 2.14: Variations between slake durability index, point load index, mineralogy, and chemistry. The mineralogy and chemical analyses were performed on splits of the same sample set that were used in the geotechnical testing and represent the mineralogy and chemistry of the sample tested by geotechnical methods. See Figure 1.2 for location of rock piles. Appendix B summarizes the location and description of these samples. .........50 Figure 2.15: Variation in slake index and point load index of the Questa rock materials. 51 Figure 2.16: Variations between slake durability index, point load index, friction angle, and residual friction angle. The friction angle was determined on the fine-grained matrix from the same location as the samples tested for slake durability and point load, which were determined on larger rock fragments. See Figure 1.2 for location of rock piles. See Figure 1.3 for location of trenches in GHN where samples were obtained. Appendix B summarizes the location and description of these samples. ...............................................52 Figure 2.17: Variation in slake index, point load index and paste pH of the Questa rock materials. See Figure 1.2 for location of rock piles. See Figures 1.2 and 1.3 for location of trenches and geologic unites in GHN where samples were obtained. Appendix B summarizes the location and description of these samples. The upper part of the figure is for the all the other rock pile location and the analogs except the GHN whereas the lower part is GHN….. ..................................................................................................................54 Figure 2.18: Variation in slake index, point load and simple weathering indices (SWI) of the Questa rock materials. See Figure 1.2 for location of rock piles. See Figures 1.2 and 1.3 for location of trenches in GHN and geologic units where samples were obtained. Appendix B summarizes the location and description of these samples. The upper part of the figure is for the all the other rock pile location and the analogs excluding the GHN whereas the lower part is GHN. .........................................................................................55 Figure 3.1: Photograph of Goat Hill debris flow. Boxes show location of collected samples. Collected samples consist of a bulk grab of rock material stored in 5 gallon buckets and includes matrix (soil) and rock fragments. ....................................................67 Figure 3.2: Variations of slake index, friction angle, and point load index and percent gravel with depth from the base of the debris flow profile. No observed trend of parameters with depth. .......................................................................................................71 Figure 3.3: Variations of paste pH, paste conductivity, water content and dry density with depth from the base of the debris flow profile. No clear trend was observed between the parameters and depth. ........................................................................................................72

  vii

Figure 3.4: Gradation curves for the sieve analysis on the individual samples from the debris flow profile. .............................................................................................................73 Figure 3.5: Variations of FeO and Fe oxide minerals with depth from the base of the debris flow profile. No clear trend of parameters with profile. .........................................74 Figure 3.6: Variations of total feldspar (K-feldspar+plagioclase) with depth from the base of the debris flow profile. No clear trend of parameters with profile. ...............................74 Figure 3.7: Variations of selected trace elements with depth from the base of the debris flow profile. No clear trend of trace elements with profile. ...............................................75 Figure 3.8: Variations of sulphur and SO4 with depth from the base of the debris flow ..75 Figure 3.9: Variations of sulphur/sulphate ratio with depth from the base of the debris flow profile. No clear trend of sulphur/sulphate with profile. ...........................................75 Figure 3.10: Variations of geochemical and mineralogical parameters on the X-axis and sample location along the profile from base to top on the y-axis. No clear trend of parameters with profile. .....................................................................................................76 Figure 3.11: Clay mineralogy XRD scans for the debris flow weathering profile. I = illite, C = Chlorite, S = smectite, K = kaolinite, J = Jarosite. .....................................................77 Figure 3.12: Backscattered electron microprobe image showing a cemented grain consisting of small hydrothermally-altered phenocrysts within MIN-GFA-0001 sample. The cement consists of clay minerals (illite), jarosite, and Fe oxides. The numbered points represent points for mineral chemistry. ...................................................................79 Figure 3.13: Backscattered electron microprobe image showing well cemented grains of hydrothermally-altered phenocrysts within MIN-GFA-0001 sample. Illite, jarosite and Fe oxide crystals are cementing the rock fragments. The cementation is similar in chemistry and texture as that found in the GHN rock pile. The numbered points represent points for mineral chemistry. ..............................................................................................................79 Figure 3.14: Backscattered electron image (BSE) of a soil sample from GHN rock pile showing rock fragment and associated fine-grained matrix material. Note the similarity in texture of the cementation of rock fragments in this image compared to the image in Figure 3.13. The fine-grained matrix consists of clay minerals and gypsum. ...................80 Figure 3.15: Backscattered electron microprobe image showing well-cemented hydrothermally-altered phenocrysts within MIN-GFA-0006 sample. Illite, jarosite, Fe oxide and feldspar crystals are cementing the rock fragments. The numbered points represent points for mineral chemistry. .............................................................................81 Figure 3.16: Backscattered electron microprobe image showing hydrothermally-altered phenocrysts within MIN-GFA-0006 sample. Illite, jarosite, Fe oxide and kaolinite crystals cementing the rock fragments. The numbered points represent points for mineral chemistry…….. ..................................................................................................................81 Figure 3.17: Sample location along the profile, sample photos and microprobe images along with sample type and strength of cementing agents. ...............................................82 Figure 4.1: Location of venting drill holes and surface vent area (SGS-JMS-0001). Blue indicates drill holes drilled in 1999 that contain monitoring instruments for temperature, O2 and CO2. Red indicates drill holes and surface vent area that do not contain temperature and gas instrumentation and are sites monitored by the New Mexico Tech team………….. ..................................................................................................................86 Figure 4.2: Temperature log of drill hole SI-50 from Sugar Shack South rock pile. ........89

  viii

Figure 4.3: Variations in slake durability index and paste pH with depth in drill hole SI-50. Temperature log is in Figure 4.2. Red lines indicate approximate boundaries of the hot zone (i.e. where temperatures exceed 50ºC). ...............................................................92 Figure 4.4: Variations in LL (liquid limit) and PI (plasticity index) with depth in drill hole SI-50. Temperature log is in Figure 4.2. Red lines indicate approximate boundaries of the hot zone (i.e. where temperatures exceed 50ºC). ...............................................................92 Figure 4.5: Variations in Gypsum+jarosite, K feldspar+plagioclase and total clay with depth in drill hole SI-50. Temperature log is in Figure 4.2. Red lines indicate approximate boundaries of the hot zone (i.e. where temperatures exceed 50ºC). ..................................93 Figure 4.6: Variation in K-feldspar+plagioclase, gypsum+jarosite, total clay and slake index of the hot zone rock materials from Sugar Shack South rock pile. ..........................94

  ix

List of Tables

Table 1.1: Questa Mine Rock Piles Description (URS Corporation, 2003) ......................11 Table 1.1 Cont ....................................................................................................................12 Table 2.1: Simple weathering index for rock-pile material (including rock fragments and matrix) at the Questa mine. ................................................................................................24 Table 2.2: Point load strength index classification (Broch and Franklin, 1972). ..............32 Table 2.3: Slake durability index classification (Franklin and Chandra, 1972). ...............34 Table 2.4: Visual descriptions of the remaining rock pieces after the second cycle. ........34 Table 2.5: Summary descriptive statistics of the strength classification for all samples. Samples from Southwest Hansen (SWH) and Hansen (HAS) alteration scar were too weak to perform point load test, hence those point load test results are not included in this table. This was probably a result of the highly fractured nature of the samples collected from these areas. ................................................................................................................40 Table 2.6: Summary descriptive statistics of the durability classification for all samples.41 Table 3.1: Comparison of the different weathering environments in the rock piles and analog sites in the Questa area. QSP=quartz-sericite-pyrite. .............................................62 Table 3.2: Summary of sample preparation for specific laboratory analyses for samples collected from the weathering profile. XRF–X-ray fluorescence analyses, XRD–X-ray diffraction analysis, slake durability tests, point load tests. ...............................................65 Table 3.3: Description of the debris flow profile. ..............................................................67 Table 3.4: Geological and geotechnical parameters of samples collected from the debris flow profile. Samples MIN-GFA-0006 and MIN-GFA-0007 did not contain rock fragments but rather soils materials due to the nature of the samples, point load and slake durability tests were not performed on them. ....................................................................68 Table 3.5: Chemical composition of samples collected from debris flow profile. Oxides are in weight percent and trace elements are in parts per million. .....................................69 Table 3.6: Mineral composition of samples collected from debris flow profile, in weight percent (as determined by quantitative mineralogy method from the modified ModAn method, McLemore et al., 2009). QSP=quartz, pyrite, sericite alteration and QMWI= Questa mineral weathering index. ......................................................................................70 Table 4.1: Slake durability indices for samples in drill hole SI-50 from Sugar Shack South and their individual classification (Franklin and Chandra, 1972). ..........................89 Table 4.2: Point load strength indices for samples in drill hole SI-50 from Sugar Shack South and their strength classification. (Broch and Franklin, 1972). Most of the samples did not have big rock fragments for the point load test since the samples were collected from drill cutting. ...............................................................................................................90 Table 4.3: Atterberg Limits through drill hole SI-50 from Sugar Shack South (URS, 2003)…………. .................................................................................................................90

This thesis is accepted on behalf of the

Faculty of the Institute by the following committee:

_________________________________________________________ Research Advisor

__________________________________________________________ Academic Advisor

__________________________________________________________ Committee Member

___________________________________________________________ Date

I release this document to the New Mexico Institute of Mining and Technology.

_____________________________________________________________ Student's Signature Date

 

1

1.0 INTRODUCTION

1.1. Background

Chevron Mining Inc. funded a multidisciplinary study to investigate how and to

what extent weathering affects the gravitational stability of the Questa mine-rock piles in

100 and 1000 years at their mine near Questa, New Mexico. This research work covers

four of the rock piles and the analogs (alteration scars and debris flow).

Point load and slake durability tests are two of the geotechnical tests being

conducted on samples from the Questa mine, rock piles and analogs to determine their

intact rock strength and durability. The purpose of this work are to determine if there is

any correlations between point load strength index and slake durability index with

internal friction angle, chemistry, mineralogy, and weathering indices in order to

determine the effect of weathering on the geotechnical parameters, characterize the debris

flow and study the strength of the hot zone-rock fragments. The debris flows in the

Questa area are identified as natural analogs for future weathering of the rock piles,

because they have undergone hydrothermal alteration, weathering, and erosion since they

were formed and could represent the future weathering of the rock piles.

Past studies by D’Andrea et al. (1964), Broch and Franklin (1972), Bieniawski

(1975), Hassani et al. (1980), Gunsallus and Kulhawy (1984) and Panek and Fannon

(1992), are well known with regard to point load testing. These studies have introduced

correlations between point load strength index and other geotechnical parameters.

Franklin and Chandra (1972), Rodrigues (1991), and Dick and Shakoor (1995) also

confirmed that, slaking of rocks is an important consideration in evaluating the

engineering behavior of rock-mass and rock-materials in geotechnical practice. Hence

 

2

strength and durability are important geotechnical parameters used in evaluating intact

rock strength and durability.

Dick and Shakoor (1995) emphasized the fact that, slake durability is an

important rock characteristic property that controls the stability of natural and man-made

slopes. The slaking behavior of a rock has a major influence in rock failure (Dhakal et al.

2002). Also, Johnson and DeGraff (1988) and Cetin et al. (2000), explained that the non-

durable behavior of the rocks comes from the long and short-term influence of chemical

weathering. This indicates how necessary it is to study weathering processes and slaking

property. It is also important to determine the mineralogy and textural properties of the

rocks when assessing the slaking property.

The point load strength index is one of the suitable methods used to determine the

strength of intact rock. It can test irregular lumps of rock samples, which makes it

suitable for studying weathered rocks, many of which cannot be machined into regular

shaped specimens since they might be too broken or too friable.

1.2 Thesis Overview

This thesis research is not organized in the traditional manner of thesis. Instead, it

is a compilation of one published manuscript and two unpublished project reports. Thus,

this thesis is divided into five chapters:

• Chapter 1 contains a general background of this research and a project site

description.

• Chapter 2 is the manuscript submitted and accepted as a SME preprint for the

2009 annual meeting (Ayakwah et al, 2009).

 

3

• Chapter 3 is an unpublished report to Chevron Mining company (McLemore,

et al., 2009).)

• Chapter 4 is a characterization of slake durability and point load of samples

from the hot zone studying the front rock piles and is taken from McLemore et

al. (2008),

• Chapter 5 presents the Conclusion and Recommendation of this study.

1.3 Project Background

Chevron Mining Inc., formerly Molycorp Inc., the owner and operator of Questa

molybdenum mine, initiated the Questa Rock Pile Weathering and Stability Project

(QRPWASP) in 2002. The company requested Letters of Intent to do Research from

qualified university researchers and research groups to investigate the potential effect of

weathering on the stability of rock piles at its mine (Molycorp Inc., 2002). The purpose of

the research is to investigate the geochemical and physical weathering effect over time on

the mine’s rock pile fabric, water movement through the rock piles, and the mechanical

properties of the mine rock piles.

The University of Utah put together a team of university researchers and consultants

from the United States and Canada to embark on the rock pile weathering study, which is

currently known as the Questa Rock Pile Weathering Stability Project. The team is made

up of geologists, geophysicists, geochemists, hydrologists, biologists, geotechnical

engineers, students and other supporting staff from the following academic and

consulting organizations:

• Geochimica Inc., Aptos, CA, USA

• Minnesota Department of Natural Resources, St. Paul, MN, USA

 

4

• New Mexico Bureau of Geology and Mineral Resources, Socorro, NM, USA

• New Mexico Institute of Mining and Technology, Socorro, NM, USA

• R2 Incorporated, Denver, CO, USA

• Soil Vision Systems Ltd., Saskatoon, SK, Canada

• Spectral International Inc., Arvada, CO, USA

• The University of Utah, Salt Lake City, UT, USA

• University of British Columbia, Vancouver, B.C., Canada

• University of California, Berkley, CA, USA

• University of Nevada, Reno, NV, USA

• Weber State University, Ogden, UT, USA

This thesis work is part of the stability study.

1.4 Thesis Objective and Scope

The purpose of this work is to examine the relationship between chemistry,

mineralogy, and weathering indexes with some geotechnical parameters in order to

determine the effect of weathering on the geotechnical parameters. The objectives of this

study are as follows:

• To determine the strength and durability of the rock particles within the rock

piles, the debris flow and the alteration scars by performing point load strength

and slake durability tests.

• To determine possible relationships between geotechnical parameters and

mineralogy, chemistry and simple weathering indexes.

• To characterize the debris flow.

 

5

• To study the durability of rock fragments from the hot zone.

1.5 Description of study area

 1.5.1 Location

The Questa mine is operated by the Chevron Mining Inc., formerly Molycorp,

Inc., and is 5.6 km (3.5 miles) east of the village of Questa, in the Taos County, in the

western part of the Taos range of the Sangre de Cristo Mountains, in the northern part of

New Mexico (Fig. 1.1). The mine is on the south-facing slope of the north side of the Red

River valley between an east-west trending ridgeline of the Sangre de Cristo Mountains

and State Highway 38 to the Red River at 2438m elevation (URS Corporation, 2003).

 

6

Figure 1.1: Location map of the Questa mine.

1.5.2 History of Questa Mine

In 1914, two local prospectors staked multiple claims in an area of the Sangre de

Cristo mountain range called Sulphur Gulch. They discovered a dark, metallic material

thought to be graphite at the time of exploration. In 1919, a sample was sent to the

laboratory to be analyzed for gold and silver. Molybdenum was rather found to be

present. Molybdenum (Mo) is a refractory metallic element used principally as an

alloying agent in steel, cast iron, and superalloys to enhance hardenability, strength,

toughness, wear and corrosion resistance (Molycorp, 2007). R&S Molybdenum Mining

Co. began underground mining in the Sulphur Gulch of the high grade molybdenum

veins in 1918 and by June 1920, Molybdenum Corporation of America (Molycorp) was

formed and acquired the R&S Molybdenum Mining Co.

 

7

In August of 1923, Molycorp acquired the June bug mill in Elizabethtown, NM.

This mill could produce one ton of molybdenum concentrate daily from every 25 tons of

ore. All molybdenum production during this time was from high grade, vein molybdenite

(MoS2) with grades running as high as 35% molybdenum. This mill was one of the first

floatation mills in North America. The mill was rebuilt several times and operated on a

continuous basis until 1956, when the underground mining operations ceased. In 1963,

the mill was dismantled in order to make way for the current mill.

By 1926, the demand for molybdenum continued to increase and Molycorp’s

Questa mine was the second largest producer of molybdenite in the world. The cost of the

mining operation increased significantly in Questa until 1941. This resulted in the

construction of a tunnel from Red River Canyon to the ore deposits, to decrease haulage,

drainage and ventilation expenses.

From 1957 to 1960, exploration by drifting, cross cutting and core drilling

methods was conducted under contract with the Defense Minerals Exploration Act. In the

early part of 1963, it was discovered that, an open pit mine was economically feasible. In

1964 alone they completed 51816 m of diamond and rotary drilling and made

considerable underground bulk sampling. Molycorp continued with open pit development

at Questa, and by 1965 the first open pit ore was delivered to the new 10,000 tpd mill.

Exploration and development drilling were also a priority to provide additional

reserves and also for ore control. Pre-production stripping was started in September 1964,

and the first ore from the pit was delivered to the mill in January 1966. During the open

pit mining production period, approximately 317.5 million metric tons of overburden

rock were stripped and deposited onto mountain slopes and into tributary valleys forming

 

8

the rock piles examined in this study (URS Corporation, 2003). The elevation of these

rock piles ranges from 134 to 482 m.

Molycorp was acquired by Union Oil Company of California (UNOCAL) in

August 1977. In November 1978, re-development of the existing underground mine

began with two vertical shafts bottoming out at approximately 396 m deep. A mile-long

decline was also constructed from the existing mill area to the haulage level. The mill

floatation area was restructured to accommodate the higher grade of underground ore.

In January 1982, mining from the open pit ceased and in August of 1983, the new

underground mine began operating using block caving techniques. Employment at this

time reached approximately 900 workers. In 1986, an extremely "soft" market caused the

first shutdown of the mine in recent history. The mine was re-opened in 1989 and

continued to operate until January 1992, when the mine ceased production for the second

shutdown due to low prices of the commodity. The mine re-started in 1995 with the

majority of the year devoted to restoration, such as dewatering and repair. Development

of the next ore body (“D” Ore Body) began in 1998 and production began in October

2000. Molycorp Inc. was acquired by Chevron Mining Inc. in 2007.

1.5.3 Mine Features

The location of the mine rock piles and other mine features are shown in Figure

1.2. The nine mine rock piles that were constructed from 317.5 million metric tons of

overburdened and mine rocks during the surface mining period (URS Corporation, 2003)

are the most noticeable features at the mine site. The rock piles are situated on the

mountain slopes adjacent to the open pit and include Middle, Sugar Shack South and Old

 

9

Sulphur (Sulphur Gulch South) rock piles whose toes are along State Highway 38 and

can easily be seen when driving on the road. These piles are referred to as the Front Rock

Piles or Roadside Rock Piles and are together with Sugar Shack West, on the south-

facing slopes of the mountain. On the east side of the pit are Spring Gulch and Blind

Gulch/Sulphur Gulch North rock piles. Capulin, Goathill North and Goathill South rock

piles are on west-facing mountain slopes on the west side of the open pit.

Figure 1.2: Map of chevron mine site showing mine rock piles and mine features.

These mine rock piles cover a surface area of approximately 2.75 million m2 and

extend vertically from just above the elevation of the Red River 134 m to approximately

482 m, resulting in some of the highest mine rock piles in North America (Wels et al.,

2002). They are typically at angle of repose and have long slope lengths (up to 610 m),

 

10

and comparatively shallow thicknesses, (Lefebvre et al., 2002). Table 1.1 summarizes the

description of the various nine mine rock piles.

The Goathill North (GHN) rock pile is one of the nine rock piles created during

the open-pit mining and contains approximately 16 million metric tons of overburden

material with slopes similar to the original topography. GHN was divided into two areas

namely: a stable area and an unstable area. The unstable area has slid down the slope

since its construction. Molycorp stabilized this rock pile by removing material from the

top portion of both areas to the bottom of the pile (Norwest Corporation, 2003). This

decreased the slope, reduced the load, and created a buttress to prevent movement of the

rock pile. During the progressive down-cutting of the top of the stable portion of GHN

(regrading), trenches were constructed to examine, map, and sample the internal geology

of the rock pile. End-dumping generally results in the segregation of materials with the

finer-grained material at the top and coarser-grained material at the base. The resulting

layers locally are at, or near, the angle of repose and subparallel to the original slope

angle. Detailed geologic mapping and sampling revealed that, these layers could be

defined as mappable geologic units in the rock pile (Fig. 1.3). Units were defined on the

basis of grain size, color, texture, stratigraphic position, and other physical properties that

could be observed in the field (McLemore et al., 2005, 2006a, 2006b, and 2008). Units

were correlated between benches and opposite sides of each trench, and several units

were correlated down slope through the excavated trenches.

 

11

 Figure 1.3: Conceptual geological model of GHN rock pile, as interpreted from surface mapping, detailed geologic cross-sections, trenches, drill holes, construction method and observations during reclamation of GHN (McLemore et. al., 2008a)

Table 1.1: Questa Mine Rock Piles Description (URS Corporation, 2003) Rock pile Maximum

height (ft) Maximum

thickness (ft) Footprint

(acres) Slope area

(acres)

Slope Overall slope

Quantity of rock (million

tons)

Sugar Shack West

980 200 43 50.7 1.7 to 1.5H:1V

1.6H:1V 31

Sugar Shack South

1580 400 128.4 151.4 2.1 to 1.4H:1V

1.6H:1V 53

Middle 1300 500 140 155.76 1.1 to 1.4H:1V

2.1H:1V 46

Sulphur Gulch

750 350 70.9 75 3.3 to 1.5H:1V

2.9H:1V 80

 

12

Blind Gulch

740 375 128.3 134 2.0 to 1.4h:1V

3.7H:1V 36

Spring Gulch

770 325 84.9 89 2.0 to 1.6H:1V

3.0H:1V 31

Capulin 440 225 44.4 47.6 3.7 to 1.3H:1V

1.7H:1V 26

Goathill North

630 200 56.8 59 5.7 to 1.4H:1V

2.3H:1V 16

Goathill South

500 75 8.8 10 1.9 to 1.5H:1V

1.6H:1V 9

Table 1.1 Cont Rock pile Years placed on

benches Years placed on

slopes Soil loss

(tons/acre/year) Annual soil loss

(tons/year)

Sugar Shack West

1969, 1973, 1974, 1976, 1977

32 1376

Sugar Shack South

1974 1973, 1974, 1976, 1979

34.7 4442

Middle 1974, 1979, 1991 1974, 1976, 1077 31.9 4466

Sulphur Gulch

1973, 1974, 1977, 1979, 1991, 1997

1969, 1974, 1976 34.7 2464

Blind Gulch 1973, 1974, 1991, 1997

1976, 1977 12.7 1626

Spring Gulch 1969, 1973, 1974, 1976, 1977, 1991

1976 8 680

Capulin 1974, 1976, 1977 22 968

Goathill North

1964-1974 22.8 1300

Goathill South

1969 21 189

1.5.4. Mine geology and mineralogy

Schilling (1956), Rehrig (1969), Lipman (1981), Carpenter (1968), and Meyer

and Leonardson (1990; 1997) summarized the geology and mineralogy of the area under

 

13

study. Figure 1.4 is a simplified geologic map of the Questa-Red River vicinity (from

Ludington et al., 2004).

 Figure 1.4: Geologic map of Questa – Red River Vicinity (Ludington et al., 2004.)

Caine (2003) stated that, the Red River Valley which is located along the southern

edge of the Questa caldera, contains complex structural features and extensive

hydrothermal alteration.

The Questa molybdenite deposit formed 24.5 million years ago during and after

an extensive period of volcanic activity. At that time, extremely hot water originated

from molten rock (magma) about a mile below the earth’s surface. When the magma

solidified and the hot water cooled down, molybdenite together with other minerals listed

 

14

in Table 1.2 precipitated from the water to fill fractures and form the veins that define the

Questa orebodies. Table 1.2 summarizes some of the minerals found in the mine area.

Table 1.2: Relative stabilities, approximate concentrations, and compositions of minerals found in Questa rock pile deposits (NM Tech electron microprobe results in bold, other elements by Molling, 1989; Shum, 1999; Piche and Jebrak, 2004; Plumlee et al., 2006; McLemore et al., 2008). Tr=trace, Approx=approximate.

Relative stability

Mineral Approx %

Primary elements

Trace elements

Formula

Easily weathered

pyrite 0-8 Zn, S Cd FeS2

calcite 0-5 Cu, Fe, S CaCO3

anhydrite tr Pb, S Ag CaSO4

hornblende 0-tr Ca, Mo

Biotite/ phlogopite

0-13 Ca, W Kfe3AlSi3O10(OH)2

apatite 0-1 Be, Al, Si Ca5P3O12·OH

jarosite 0-0.5 Mn, Be, Si Zn KFe3(SO4) 2 (OH)6

alunite 0-0.5 Bi, S

copiapite 0-0.5 Fe, Mn, W Fe+2(Fe+3)4(SO4)6(OH) 2·20H2O

schwertmanite 0-0.01 Ca, F Y Fe16O16(OH,SO4)12–13·10H2O

sphalerite 0-0.1 Mg, Ca, CO

Sr, Al, Mg, Mn, Fe, Si,

Ba

ZnS

chalcopyrite 0-0.1 Mn, Ca, CO

CuFeS

galena 0-0.1 N, Al, Si Cu, Ga, Ba, Sr,

PbS

powellite 0-0.1 K, Al, Si Rb, Ba, Sr, Cu, Ga

CaMoO4

scheelite 0-0.1 Ca, Al, Si Ba, Sr, CaWO4

beryl 0-0.1 K, Al, Si F, Cl, Ti, Cr, Mg, Na, Ca, Mn, Fe,

Be3Al2Si6O18

 

15

Relative stability

Mineral Approx %

Primary elements

Trace elements

Formula

Rb, Ba, Sr, Ga, V, Be?,

Li?

helvite 0-0.1 Fe, Ti Al, Mg, Ca, Mn,

Zn, Co, Ni, Cr, V

Mn4Be3(SiO4) 3S

bismuthinite 0-0.1 Ca, Al, Si Cr, Mg, Mn, Fe, Na, Ti

Bi2S3

wolframite 0-0.1 Fe, Al, Mg, Si, Be?

F, Be?, Li?, various

(Fe,Mn)WO4

Moderately weathered

fluorite 0-0.1 Si, Al, Mg, Ca, Na, K,

Be?

P, S, Ti, Mn, Fe, F,

Cl, Be?, Li?

CaF2

dolomite 0-0.1 Fe, Cr MgCa(CO3) 2

rhodochrosite 0-0.1 Ca, Ti, Si MnCO3

albite Ti NaAlSi3O8

orthoclase 0-24 Be KAlSi3O8

anorthite 0-20 Ba, S Sr CaAl2Si2O8

Muscovite (sericite, illite)

0-30 Ca, Mg, Si, OH

KAl2(Si3Al)O10(OH) 2

magnetite 0-1 Si Fe3O4

Epidote 0-16 Al, H, Si F, Cl CaFeAl3 (SiO4)3(OH)

chlorite 0-12 Ca, S Sr, Ba Mg3Fe2Al2Si3O10(OH)8

smectite 0-24 Fe Ca0.33(Mg0.66Al3.34)(Si8)(OH) 4

chromite 0-0.1 Fe Various FeCrO4

titanite 0-0.1 Fe, Al Various CaTiSiO4·OH

rutile 0-0.1 Fe, Mn, Ti various TiO2

 

16

Relative stability

Mineral Approx %

Primary elements

Trace elements

Formula

beryl 0-0.01 Mo, S BeO

barite 0-0.01 Si, Fe, Mn, Al

various BaSO4

actinolite 0-1 Zn, S Cd Ca2Mg5Si8O22 (OH) 2

Very stable quartz 0-66 Cu, Fe, S SiO2

kaolinite 0-7 Pb, S Ag Al2Si2O5(OH) 4

gypsum 0-20 Ca, Mo CaSO3·H2O

ferrihydrite 0-0.01 Ca, W Fe(OH) 3

hematite 0-10 Be, Al, Si

goethite 0-1 Mn, Be, Si Zn FeOOH

FeMnTi oxides

(goethite, hematite, etc.)

0-10 Bi, S

molybdenite 0-0.1 Fe, Mn, W MoS

Amorphous Si, Fe, Mn, Al

? Ca, F Y various

The molybdenite orebodies are part of a zone of hydrothermal alteration that contains

varyibg amounts of pyrite and extends along the Red River valley, and is similar in

mineralogy, lithology, and hydrothermal alteration, to the adjacent Red River mining

district. A zone of bleached and weathered rocks overlies the pyrite zone. The bleached

and weathered rock zone extends up to 914.4 m wide. There also exist steep cliffs with no

vegetation which define areas of active mass wastage (landslides), and which are agents

of acid rock weathering. When the pyrite mineral decomposes in the presence of water,

oxygen and bacteria it forms sulfuric acid, which can lead to weathering (Molycorp Inc.,

2007)

 

17

One of the most visible geologic features of the Questa-Red River region are

naturally formed alteration scars (Fig. 1.5). The scars are source areas for mudflows and

have considerably changed the topographic form of the Red River since the last ice age.

McLemore et al. (2004d) and Meyer and Leonardson (1990) stated that these alteration

scars are natural, multicolored (red to yellow to orange to brown), comparatively unstable

landforms that are distinguished by steep slopes (greater than 25 degrees), moderate to

high pyrite content (typically greater than 1 percent), little or no vegetation, and

extensively fractured bedrock.

Figure 1.5: Map of the alteration scars at the Questa Mine. The red circles shows where samples were taken from, for point load and slake durability test.

1.6 Rock mass and intact rock strength

Rock strength is defined as the rock withstanding deformation until their brittle

failure. Brittle failure is a process that occurs when rocks alter from one behavior state to

 

18

another and consists of the entire process of deformation up to the peak resistance.

Propagating pre-existing cracks is a function of brittle failure. Rock strength is

dependent on many factors such as strength of intact rock, degree of weathering, joint

spacing, joint orientation, joint width, joint continuity and infill and the flow of ground

water through the joints.

Rock mass and intact rock strength can be achieved by performing a variety of

tests. The easiest and quickest tests are the simple hammer and pocket test which

provides qualitative rock strength classification. Triaxial, point load strength, uniaxial

compressive strength, brazilian strength and direct shear tests are some of the

geotechnical tests performed on rock and soil samples to determine the strength of the

sample and to aid in geotechnical evaluation of the stability of the area under study.

Broch and Franklin (1972) stated that, some of these tests are more sophisticated, and

most provide reliable qualitative and quantitative results. The point load strength test,

which was used in this research is practical, sensitive and provides reliable results.

1.6.1 Rock durability and slaking

Durability is defined as the resistance of rock to weakening and disintegration

when subjected to short term weathering over time (Fookes et.al, 1971). Quine (1993),

described slaking as the swelling or disintegration of a rock by the interaction of clay

minerals with water.

Kolay and Kayabali, (2006) described that; rocks containing high-plasticity clays

may swell, shrink and slake. Excessive slaking could lead to rapid weathering of exposed

 

19

rocks which are prone to earthfills failure, slope stability problems and also strength

reduction with rocks exposed to air in underground openings (Gokceoglu et al., 2000)

There are several types of durability such as: frost-durability, abrasion-durability,

chemical-durability, breakdown-durability, and slake-durability depending on the type of

weathering or resistance influence. For the purpose of this research, slake durability test

was used and is described in the 2.3.2 section of chapter 2. The slake durability index is

an important parameter for rock materials and rock masses (Franklin and Chandra, 1972;

Gokceoglu et al., 2000; Dhakal et al., 2002; Dhakal et al., 2004). The susceptibility of

rocks to weathering and the degree of weathering could be estimated using slake

durability index. This is an important engineering parameter for rocks such as mudstone,

marl, ignimbrite, weakly cemented conglomerate, and siltstone (Gokceoglu et al., 2000).

Zhao et al. (1994) used the notion of slake durability to study the weathering processes of

granitic rocks.

Kolay and Kayabali (2006), investigated the effect of aggregate shape and surface

roughness on the slake durability index using the fractal dimension approach and

concluded that, the best results can be achieved when well rounded samples having the

lowest fractal values are used since the rounded aggregates plotted relatively in a narrow

range as compared to the angular and subangular aggregates. Kolay and kayabali, 2006

concluded that, rocks with lower slake durability indices are more susceptible to the

variations with the aggregate shape and surface roughness.

Gokeoglu et al., 2000 examined the factors affecting the durability of selected

weak and clay bearing rocks from Turkey, with emphasis on the influence of the number

of drying and wetting cycles and concluded that, with the exception of the rocks with a

 

20

higher clay percentage, the results from the second cycle ranges from 88.1 to 99.8% and

described these rock types correspond to high carbonate content, whereas the rock types

with a higher clay content had low durability of 0 to 70% from the second cycle.

Dhakal et al. (2004) stated that slake durability of rocks increases as the

concentration of dissolved electrolytes, such as sodium chloride increases. Acidic

environment severely affects rocks rich in calcium carbonate and or magnesium

carbonate whereas, rocks rich in quartz, feldspar and muscovite are not dependent on the

pH of the slaking fluid (Gupta and Ahmed, 2007).

Dick and Shakoor (1995) investigated into the durability of mudrocks for slope

stability purposes. They classified the durability of mudrocks as high, medium or low on

the basis of relationships between lithologic characteristics, slake durability, and slope

conditions and used their classification to assess the possibility of occurrence of

excessive erosion, slumps, debris flows and undercutting-induced failures. They

concluded that, high-durable materials are susceptible to undercutting, medium-durability

mudrocks to slumps, debris flows and undercutting-induced failures and lastly low-

durability mudrocks to all types of slope instability.

Dhakal et al. (2002) examined the effect of mineralogical properties on the slake

durability of some pyroclastic and sedimentary rocks and concluded that the slake

durability of tuffaceous sandstone decreases as the degree of weathering increases.

Viterbo, 2007 studied the slake durability and point load strength from the

Goathill North (GHN) rock pile, one of the nine rock piles at the Questa Mine and

concluded that the rock fragments are still quite strong even after being highly fractured

and altered before being blasted, then emplaced in the pile and subsequently weathered.

 

21

This research work continues the work by Viterbo (2007), on four of the nine rock piles

and the analogs from the Chevron Mine.

 

22

2.0 EFFECTS OF WEATHERING AND ALTERATION ON POINT

LOAD AND SLAKE DURABILITY INDICES OF QUESTA MINE

MATERIALS, NEW MEXICO

2.1 Introduction

Point load strength and slake durability indices are two important geotechnical

parameters that can be used in characterizing the strength of rock fragments and their

durability to weathering. The point load strength index is one of several suitable methods

used to determine the intact rock strength. Because point load strength testing can be

applied to irregular rock samples, it is suitable for studying weathered rocks, many of

which cannot be easily machined into regular shaped samples, because they are too

fractured or friable. The slake durability test was developed to evaluate the influence of

alteration on rocks by measuring their resistance to deterioration and breakdown when

subjected to wetting and drying cycles. The purpose of this study is 1) to determine the

strength and durability rock fragments, 2) to determine how point load strength and slake

durability indices are affected by the chemistry and mineralogy of rocks, and 3) to

determine the effect of weathering and alteration of the Questa mine materials on these

indices.

The durability of rocks can be described as their resistance to breakdown under

weathering conditions over time. Slaking occurs from the swelling of clay minerals in

rocks when they come into contact with water. The slake durability index measures the

durability of rocks. It gives quantitative information on the mechanical behavior of rocks

 

23

according to the amount of clay and other secondary minerals produced in them due to

their exposure to weathering (Fookes et al., 1971).

Many researchers have studied the point load strength of rocks and have tried to

correlate the point load strength index with other geotechnical parameters (D’Andrea et

al., 1964 ; Broch and Franklin, 1972; Bieniawski, 1975 ; Hassani et al., 1980; Gunsallus

and Kulhawy, 1984 and Panek and Fannon, 1992). Franklin and Chandra (1972),

Rodrigues (1991), and Dick and Shakoor (1995) suggest that slaking of rocks is also an

important consideration in evaluating the engineering behavior of rock mass and rock

materials in geotechnical practices. Dick and Shakoor (1995) emphasized the fact that

durability is an important rock characteristic parameter controlling the stability of natural

and man-made slopes. Dhakal et al. (2002) indicated that the slaking behavior of a rock

has a major influence on rock failure. Johnson and DeGraff (1988) and Cetin et al. (2000)

explained that the non-durable behavior of rocks is a result of the long- and short-term

influences of chemical weathering; this indicates how necessary it is to assess weathering

and to determine the mineralogy and textural properties of rocks when assessing the

slaking property. Dhakal et al. (2002) stated that the slaking behavior of pyroclastic

(similar to the Questa volcanic rocks) and sedimentary rocks can play a major role in

slope failure. Nevertheless, very few studies of rock piles evaluate point load and slake

durability tests with respect to mineralogy, chemistry and other geotechnical parameters

of the tested rocks. Actual slake durability and point load indices from researchers such

as Quine (1993) reported point load indices for some rock- pile samples collected in

Nevada that ranged from 2.9 to 4.6 MPa, while the slake durability indices ranged from

88 to 99% with an additional single value of 6%. Samples from the Eskihisar lignite mine

 

24

in Turkey (Gökçeoglu et al., 2000) had slake durability indices ranging from 88.7 to

96.8%, and rock pile-material from a marble mine in India had slake durability indices

ranging from 89.9 to 97.0% (Maharana, 2005).

2.2 Alteration and weathering of the Questa rock piles

Rock fragments in the Goathill North (GHN) samples are comprised of two main

lithologies, which are andesite and rhyolite (Amalia Tuff). Intrusive rocks, although

present within colluvium/weathered bedrock, alteration scar, debris flows, and other rock

piles are minor to absent within the GHN rock pile. All three rock types exhibit original

igneous textures, although the andesite fragments have typically undergone significant

hydrothermal alteration, whereas the rhyolite (Amalia Tuff) fragments are relatively

pristine or consisted of QSP alteration. The rhyolite (Amalia Tuff) fragments consisted of

large (~mm size) quartz and feldspar phenocrysts, surrounded by a devitrified glass

matrix. Three types of alteration have been described at Questa, including propyllitic,

quartz-sericite-pyrite (QSP), and argillic, although relict igneous textures are typically

evident (McLemore et al., 2008b). Rough estimates of the intensity of these three

alteration styles in the GHN rock pile were made petrographically. Although the ranges

of intensity of alteration styles within a single rock-pile unit are large, QSP alteration is

the most prevalent style, and argillic alteration is relatively minor. Propyllitic alteration is

present throughout the rock pile, although, at a lower intensity than QSP. There appears

to be slightly more propyllitic alteration in the interior rock-pile units (McLemore et al.,

2008b).

 

25

The evidence for weathering in the Questa rock piles includes (McLemore et al.,

2006a, b, 2008a):

• Change in color from darker brown and gray in less weathered samples (original

color of igneous rocks) to yellow to white to light gray in the weathered samples

• Thin yellow to orange, “burnt” layers within the interior of GHN, where water

and/or air flowed and oxidized the rock pile material

• Paste pH, in general, is low in oxidized, weathered samples and paste pH is higher

in less weathered samples

• Presence of jarosite, gypsum, iron oxide minerals and Fe-soluble salts (often as

cementing minerals), and low abundance to absence of calcite, pyrite, and epidote

in weathered samples

• Tarnish or coatings of pyrite surfaces within weathered samples

• Dissolution textures of minerals (skeletal, boxwork, honeycomb, increase in pore

spaces, fractures, change in mineral shape, accordion-like structures, loss of

interlocking textures, pits, etching) within weathered samples (McLemore et al.,

2008a)

• Chemical classification as potential acid-forming materials using acid base

accounting methods (Tachie-Menson, 2006)

• Cementation of rock fragments and soil matrix

• Chemical analyses of water samples from the toe of GHN characterized by acidic,

high sulfate, high TDS, and high metal concentrations (Al, Ca, Mg, Fe, Mn, SO4).

In GHN, typically, paste pH increased with distance from the outer, oxidized units

(west) towards the interior units (east) of the GHN rock pile. The outer units were

 

26

oxidized (weathered) based upon the white and yellow coloration, low paste pH, presence

of jarosite and authigenic gypsum, and absence of calcite. The base of the rock pile

adjacent to the bedrock/colluvium surface represents the oldest part of the rock pile

because it was laid down first. Portions of the base appeared to be nearly or as oxidized

(weathered) as the outer, oxidized zone of the rock pile. This suggests that air and water

flowed along the basal interface, implying that it must be an active weathering zone.

Numerous weathering indices were evaluated in the current research. A

weathering index is a measure of how much a sample has weathered. Most of the

weathering indices in the literature are based only on geochemical parameters, which

restrict their application to the type of environment for which they were developed. These

weathering indices actually measure both pre-mining hydrothermal alteration and post-

mining weathering. A simple weathering index (SWI) was developed to differentiate the

weathering intensity of Questa rock pile materials in the field (SWI=1, fresh to SWI=5,

most weathered; Table 2.1; Gutierrez et al, 2008). The 5 classes in Table 2.1 describe the

SWI classification for the mine soils at the Questa mine based on relative intensity of

both physical and chemical weathering (modified in part from Little, 1969; Gupta and

Rao, 2001; Blowes and Jambor, 1990).

The SWI accounts for changes in color, texture, and mineralogy due to

weathering, but it is based on field descriptions. Some problems with this weathering

index are:

• It is subjective and based upon field observations.

• This index does not always enable distinction between pre-mining supergene

hydrothermal alteration and post-mining weathering.

 

27

• The index is developed from natural residual soil weathering profiles, which

typically weathered differently from the acidic conditions within the Questa rock

piles and, therefore, this index may not adequately reflect the weathering

conditions within the rock piles.

• This index refers mostly to the soil matrix; most rock fragments within the

sample are not weathered except perhaps at the surface of the fragment and

along cracks.

• The index is based primarily upon color and color could be indicative of other

processes besides weathering intensity.

• This index was developed for the Questa rock piles and may not necessarily

apply to other rock piles.

• Weathering in the Questa rock piles is a semi open not a closed system (i.e.

water analysis indicates the loss of cations and anions due to oxidation).

Table 2.1: Simple weathering index for rock-pile material (including rock fragments and matrix) at the Questa mine.

SWI Name Description 1 Fresh Original gray and dark brown to dark gray colors of igneous rocks; little to

no unaltered pyrite (if present); calcite, chlorite, and epidote common in some hydrothermally altered samples. Primary igneous textures preserved.

2 Least weathered Unaltered to slightly altered pyrite; gray and dark brown; angular to sub-angular rock fragments; presence of chlorite, epidote and calcite, although these minerals are not required. Primary igneous textures still partially preserved.

3 Moderately weathered

Pyrite altered (tarnished and oxidized), light brown to dark orange to gray: more clay- and silt-size material; presence of altered chlorite, epidote and calcite, but these minerals are not required. Primary igneous textures rarely preserved.

4 Weathered Pyrite very altered (tarnished, oxidized, and pitted); Fe-hydroxides and oxides present; light brown to yellow to orange; no calcite, chlorite, or epidote except possibly within center of rock fragments (but the absence of these minerals does not indicate this index), more clay-size material. Primary igneous textures obscured.

5 Highly weathered No pyrite remaining; Fe-hydroxides and oxides, shades of yellow and red typical; more clay minerals; no calcite, chlorite, or epidote (but the absence

 

28

SWI Name Description of these minerals does not indicate this index); angular to sub-rounded rock fragments

Paste pH is another indication of weathering used in this project, but it has

limitations as well. Paste pH is the pH measured from a paste or slurry that forms upon

mixing soil material and deionized water. In an acidic material, paste pH is an

approximate measurement of the acidity of a soil material that is produced by the

oxidation of pyrite and other sulfides. A low paste pH (2-3) along with yellow to orange

color and the presence of jarosite, gypsum, and low presence to absence of calcite are

consistent with oxidized conditions in the Questa rock piles (McLemore et al., 2006a, b;

Gutierrez et al., 2008). In general, paste pH increases from the outer, oxidized units of

GHN to the inner, less oxidized units.

Changes of mineralogy and chemistry between the outer, oxidized zone and the

interior, unoxidized zones of the rock piles are a result of differences due to pre-mining

composition as well as chemical weathering. These differences can be difficult to

distinguish, except by detailed field observations and petrographic analysis and the

changes due to hydrothermal alteration are more pronounced than those due to

weathering. Weathering processes, intensity, and rates will differ throughout the rock

piles. Because weathering intensities and effects are so variable and dependent upon

many factors, no single weathering index is valid over the entire spectrum of weathered

states (Duzgoren-Aydin and Aydin, 2002). Therefore, several indices can be used to

indicate some aspects of weathering in the Questa rock piles (McLemore et al., 2008a):

SWI, paste pH, authigenic gypsum, sum of gypsum and jarosite, SO4, and Net NP

(neutralizing potential).

 

29

2.3 Field and Analytical Methods

2.3.1 Sampling

Samples were collected, located by GPS coordinates, bagged, labeled and

transported to New Mexico Institute of Mining and Technology (NMIMT) and stored in a

trailer. Samples consist of representative rock pieces, each weighing between 40-60 g

(approximately 4-10 cm in dimension; more details are in Viterbo, 2007). These samples

were collected specifically for examining relationships between slake durability and point

load indices and mineralogy, chemistry, lithology, geotechnical parameters, and

weathering-alteration. Several different types of samples were collected for point load

and slake durability tests and included a range of lithologies, alteration assemblages, and

weathering intensities:

• Rock fragments from rock-pile material that include mixtures of different

lithologies and alteration assemblages

o Samples collected from the surface and from test pits in the rock piles

o Samples of the rock-pile material collected from trenches in GHN (5 ft

channel or composite of selected layers)

• Outcrop samples of unweathered (or least weathered) igneous rocks

representative of the mined rock (overburden) (includes all predominant

lithologies and alteration assemblages at various hydrothermal alteration)

o andesite

o quartz latite

o rhyolite tuff (Amalia Tuff)

o aplite, granitic porphyry

 

30

o miscellaneous dike, flow, and tuffaceous rocks

o material from alteration scars

• Residual weathered soil profiles of colluvium/weathered bedrock, alteration scar,

and debris flows

• Sections of drill-core samples of the mined rock (overburden) and ore deposit

before mining.

Different sampling strategies were employed based upon the purpose of each

sampling task. Typically, at each site, the samples for this study consisted of grab

samples of two or more pieces of rock-pile material, outcrop, or drill core samples

(typically 3-8 cm in diameter). These samples are more homogeneous than a grab sample

of rock-pile samples in that they are composed of one lithology and alteration

assemblage; whereas the grab sample of rock-pile material typically consists of multiple

lithologies and/or alteration assemblage. A portion of the collected sample was crushed

and pulverized for geochemical analysis. Thin sections were made of another portion of

selected rock samples for petrographic analysis, and another portion was used for the

geotechnical testing. Rock pile locations, debris flow, GHN trenches and alteration scars

are shown in Figures 1.1, 1.2 and 1.5respectively.

2.3.2 Laboratory Analysis

Point Load Test

The point load strength test was used to determine the strength of the rock

fragments at the Questa rock piles and the analogs (debris flow and alteration scars). The

test is a relatively simple and economical for estimating rock strength. The point load test

 

31

was developed by Broch and Franklin (1972) for classifying and characterizing rock

material. The International Society of Rock Mechanics (ISRM) standardized and

established it in 1985 and it has been used for geotechnical study for over thirty years

(ISRM, 1985). The point load strength index can be used to predict other strength

parameters since it correlates closely with uniaxial tensile and compressive strengths

(Broch and Franklin, 1972; ISRM, 1985).

The point load test equipment consists of a loading frame that measures the force

required to split the sample and a system for measuring the distance between the two

contact loading points (Fig. 2.1). The point load test can be performed on samples with

different shapes, both cylindrical (core) and irregular shapes. The point load strength

index (Is50) corresponding to a specimen of 0.05 m in diameter, is calculated using

(ISRM, 1985):

FDPIs

e

×= 250 (2.1)

where P is the peak load, De is the equivalent core diameter, and F is a size correction

factor (De/0.050)0.45. All samples are classified according to the classification index in

Table 2.2. Figure 2.2 shows a sample of rock fragments after test with the planes of

failure.

 

32

Conical Platens

Display Gage

Load Handle

Figure 2.1: The point load strength equipment in use (sample under test), showing contact cones, the loading and measuring systems (display gage) and samples to be tested.

Table 2.2: Point load strength index classification (Broch and Franklin, 1972). Is50 (MPa) Strength classification

< 0.03 Extremely low

0.03 – 0.1 Very low

0.1 – 0.3 Low

0.3 – 1.0 Medium

1.0 – 3.0 High

3.0 – 10 Very high

> 10 Extremely high

 

33

Figure 2.2: Typical irregular samples after point load strength test showing their planes of failure. Slake Durability Test

Durability is defined as the resistance of rock to weakening and disintegration

when subjected to short term weathering processes (Fookes et al., 1971). Quine (1993)

described slaking as the swelling or disintegration of a rock by the interaction of clay

minerals with water. The slake durability test was developed by Franklin and Chandra

(1972), recommended by the International Society for Rock Mechanics (ISRM, 1979),

and standardized by the American Society for Testing Materials (ASTM, 2001). The

purpose of this test is to evaluate the influence of alteration on rocks by measuring their

resistance to deterioration and breakdown when subjected to simulated wetting and

drying cycles. The slake durability index (ID2) is a measure of durability and provides

quantitative information on the mechanical behavior of rocks according to the amount of

 

34

clay and other secondary minerals produced in them due to exposure to climatic

conditions (Fookes et al., 1971). The ID2 is obtained from:

1002 ×−−

=DB

DA

WWWWID (2.2)

where WB is the mass of drum plus oven-dried sample before the first cycle, WA is the

mass of drum plus oven-dried sample retained after the second cycle, and WD is the mass

of drum. All samples are classified according to the classification index in Table 2.3 and

2.4. Note that each sample used in the slake durability testing is made of 10 pieces of

rock each weighing 40 to 60 g that were collected from a specific location.

Table 2.3: Slake durability index classification (Franklin and Chandra, 1972). ID2 (%) Durability classification

0 – 25 Very low

25 – 50 Low

50 – 75 Medium

75 – 90 High

90 – 95 Very high

95 – 100 Extremely high

Table 2.4: Visual descriptions of the remaining rock pieces after the second cycle. ID2 (%) Visual description I Pieces remain virtually unchanged

II Pieces consist of large and small pieces

III Pieces consist of exclusively small fragments

The slake durability equipment comprises of a 2 mm standard square-mesh

cylinder drum of unobstructed length of 100 mm and diameter of 140 mm, with a solid

 

35

fixed base. The drum must be able to withstand a temperature of about 110±5o C. The

ends of the drum must be rigid with one of its ends removable. Both the plates and drums

should be strong enough to maintain their shapes when in use. The drum is enclosed in a

trough and is supported along the horizontal axis in a way capable of being filled with

water. In this case distilled water was used to a level of 20 mm below the drum axis

which allows at least 40 mm of unobstructed clearance between the trough and the

bottom of the mesh. A motor designed in such a way to rotate the drum at a speed of 20

rpm constantly to within 5 percent for duration of 10 minutes shown in Figure 2.3.

The rock pieces are brushed to remove all the accumulated dust on it prior to

weighing to determine the actual weight of the rock fragments. The sampling and test

procedure for the slake test is in Standard Operating Procedure, SOP 76 (Viterbo, 2007,

appendix F). The samples are placed in the drum and then weighed and then dried in the

oven for 16 hours to obtain a constant weight. The sample and the drum are left to cool at

room temperature for 20 minutes and weighed. The natural water content of the sample is

then computed. Figure 2.4 shows prepared sample before slake durability test and Figure

2.5 shows an oven dried sample after the second cycle showing bigger and smaller

fragments.

 

36

Figure 2.3: slake durability equipment during usage comprising of the test drums and the motor for rotation.

Figure 2.4: A typical brushed sample, each piece weighing between 40 to 60 g before the slake durability test is performed.

Drum comprising of 2 mm standard square mesh cylinder

Motor

 

37

Figure 2.5: A typical sample after slake durability test showing bigger and smaller pieces of rock fragments after the test.

Other Laboratory Analyses

The laboratory paste tests, direct shear test, and gravimetric moisture contents

were performed at New Mexico Institute of Mining and Technology (NMIMT) using

laboratory procedures (SOPs) established as part of the overall project procedure

documentation. Petrographic analyses (mineralogy, lithology, hydrothermal and

weathering alteration) were performed using a binocular microscope. These analyses

were supplemented by thin section petrography, microprobe, X-ray diffraction analyses,

and whole-rock chemical analyses for confirmation. Clay mineralogy, in terms of the

major clay mineral groups, was determined using standard clay separation techniques and

X-ray diffraction analyses (Hall, 2004; Moore and Reynolds, 1989). This method does

not liberate or measure the amount of clay minerals within the rock fragments.

 

38

The concentrations of major and trace elements, except for S, SO4, LOI (loss on

ignition), and F, were determined by X-ray fluorescence spectroscopy at New Mexico

State University and Washington State University laboratories. Fluoride concentrations

were determined by ion probe and LOI concentrations by gravimetric methods at

NMIMT. S and SO4 were determined by ALS Chemex Laboratory. The modified ModAn

technique (McLemore et al., 2009) provides a quantitative bulk mineralogy that is

consistent with the petrographic observations, electron microprobe analysis, clay mineral

analysis, and the whole-rock chemistry of the sample. Unlike most normative mineral

analyses, all of the minerals calculated for the bulk mineralogy are in the actual sample

analysis using ModAn. ModAn is a normative calculation that estimates modes “by

applying Gaussian elimination and multiple linear regression techniques to simultaneous

mass balance equations” (Paktunc, 2001), and allows location-specific mineral

compositions to be used. Representative mineral compositions for minerals in the Questa

samples were determined from electron microprobe analysis and used in ModAn for this

study (McLemore et al., 2009). The mineralogy and chemical analyses were performed

on splits of the same sample set that were used in the geotechnical testing and represent

the mineralogy and chemistry of the sample tested by geotechnical methods.

2.4 Results

Point load strength and slake durability tests were performed on rock samples

from the rock piles, drill cores of the mined rock drilled before open-pit mining began,

outcrops, the alteration scars, and the debris flow. The samples from drill cores represent

unweathered rock pile material, since these samples were of the open pit deposit before

 

39

mining and not exposed to surface weathering. Samples from the alteration scars and

debris flows represent materials that are exposed to weathering processes over the last

4000 years (debris flows) to 10,000 yrs or longer (alteration scars), (Graf, 2008; V. Lueth

et. al, written communication October 2008). The results are summarized in Appendix A

and B1. The methodology in evaluation of point load strength index is discussed in

Appendix B2 of this work. Summary statistics of the point load strength and slake

durability indices are in Tables 2.5 and 2.6 and Appendix B1. The individual analyses for

GHN rock pile are in Viterbo (2007) and Appendix A, Tables A1 and A2 of this work.

Histogram plot of point load strength and slake durability indices for all rock piles

are in Figures 2.6 and 2.7. The individual histogram plot for each rock pile, geologic unit

and analogs and their comparison analysis are in Appendix C.

 

40

Table 2.5: Summary descriptive statistics of the strength classification for all samples. Samples from Southwest Hansen (SWH) and Hansen (HAS) alteration scar were too weak to perform point load test, hence those point load test results are not included in this table. This was probably a result of the highly fractured nature of the samples collected from these areas.

Location Statistics Point Load Strength Index

All rock piles (GHN, Sugar Shack South, Sugar Shack

West, Middle, Spring Gulch)

No. of Samples 59 Mean (MPa) 3.8 Standard Deviation (MPa) 1.7 Minimum (MPa) 0.6 Maximum (MPa) 8.2 Coefficient of Variation (%) 44.7

All unweathered (drill core)

andesite samples

No. of Samples 19 Mean (MPa) 3.7 Standard Deviation (MPa) 1.7 Minimum (MPa) 1.3 Maximum (MPa) 6.9 Coefficient of Variation (%) 45.9

All unweathered (drill core) aplite

(intrusive) samples

No. of Samples 8 Mean (MPa) 3.6 Standard Deviation (MPa) 1.7 Minimum (MPa) 1.4 Maximum (MPa) 6.5 Coefficient of Variation (%) 47.2

All unweathered (drill core)

rhyolite (Amalia)

No. of Samples 3 Mean (MPa) 2.6 Standard Deviation (MPa) 0.7 Minimum (MPa) 1.8 Maximum (MPa) 3.1 Coefficient of Variation (%) 26.9

Debris Flow No. of Samples 12 Mean (MPa) 4.0 Standard Deviation (MPa) 1.0 Minimum (MPa) 2.6 Maximum (MPa) 6.0 Coefficient of Variation (%) 25.0

Alteration Scars (Questa Pit)

No. of Samples 4 Mean (MPa) 2.8 Standard Deviation (MPa) 0.8 Minimum (MPa) 1.7 Maximum (MPa) 3.8 Coefficient of Variation (%) 28.6

 

41

Table 2.6: Summary descriptive statistics of the durability classification for all samples. Location Statistics Slake Durability Index

All rock piles (GHN, Sugar Shack South, Sugar Shack West,

Middle, Spring Gulch)

No. of Samples 132 Mean (%) 96.4 Standard Deviation (%) 3.4 Minimum (%) 80.9 Maximum (%) 99.5 Coefficient of Variation (%) 3.5

All unweathered (drill core) andesite samples

No. of Samples 19 Mean (%) 95.1 Standard Deviation (%) 4.0 Minimum (%) 83.7 Maximum (%) 99.1 Coefficient of Variation (%) 4.2

All weathered (out crop) and

unweathered (drill core) rhyolite

(Amalia) and aplite samples

No. of Samples 16 Mean (%) 95.5 Standard Deviation (%) 3.0 Minimum (%) 88.9 Maximum (%) 99.5 Coefficient of Variation (%) 3.1

All unweathered (drill core) Aplite (intrusive)

No. of Samples 8 Mean (%) 95.7 Standard Deviation (%) 2.6 Minimum (%) 92.2 Maximum (%) 99.1 Coefficient of Variation (%) 2.7

All unweathered (drill core) rhyolite (Amalia)

No. of Samples 3 Mean (%) 93.0 Standard Deviation (%) 3.6 Minimum (%) 88.9 Maximum (%) 95.8 Coefficient of Variation (%) 3.9

Debris Flow No. of Samples 18 Mean (%) 98.4 Standard Deviation (%) 0.9 Minimum (%) 96.1 Maximum (%) 99.6 Coefficient of Variation (%) 0.9

Alteration Scars (Questa Pit, Hason, Goat Hill, Straight

Creek scars)

No. of Samples 24 Mean (%) 89.2 Standard Deviation (%) 9.2 Minimum (%) 64.5 Maximum (%) 98.5 Coefficient of Variation (%) 10.3

 

42

Point Load Strength Index (MPa)0 2 4 6 8 10

Cou

nts

0

2

4

6

8

10

12

14All Rock Piles

Figure 2.6: Histogram plot of point load strength index at the rock piles location (GHN, SSS, SSW, MID and SPR). Number of samples is 59.

Slake Durability Index %70 80 90 100

Cou

nts

0

10

20

30

40

50

60

70

80All Rock Piles

Figure 2.7: Histogram plot of slake durability index at the rock piles location (GHN, SSS, SSW, MID and SPR). Number of samples is 132.

 

43

2.5 Discussion

Samples from the GHN rock pile are relatively similar in slake durability and

point load indices regardless of the geologic layer and location within the GHN rock pile.

However, some samples located in the outer edge of the rock pile (Units C and I)

disintegrated more and presented lower durability than similar rocks around the same

area (Fig. 2.8). This suggests that for some, but not all samples, point load strength index

and slake durability index of the GHN rock pile decreased as the degree of weathering

increased. However, in general, the point load and slake indices of rock fragments are

still quite high, and suggest that 25-40 years of weathering have not substantially affected

the strength properties of these rock pile materials (Fig. 2.8, Tables B7 to B10 in

Appendix B; Viterbo, 2007; Gutierrez et al., 2008). There are similar results concerning

friction angle and slake durability index by Gutierrez et al. (2008), where lower friction

angles were obtained from some but not all weathered samples from the outer edge of the

GHN rock pile, than from samples from the interior of GHN rock pile.

 

44

Figure 2.8: Scatter plot of Slake Durability Index and Point Load Index vs. distance from outer edge of GHN rock pile. The weathering intensity was confirmed by petrographic analyses, especially textures, as described by McLemore et al. (2008a). See Figures 1.2 and1.3 for location of trenches and layers in GHN where samples were obtained. Appendix B includes a summary of the description of these samples.

The slake durability indices from the various rock piles range from 80.9 to 99.5 %

and the point load strength indices range from 0.6 to 8.2 MPa (Tables 2.5 and 2.6; Tables

B7 and B8 in Appendix B). Samples from Sugar Shack South and Spring Gulch rock

piles have a lower average of point load index than the other rock piles (Fig. 2.9; Table

B9 in Appendix B); more samples from these rock piles are needed to determine if this is

significant. Figures 2.9 and 2.10 show the range of point load strength and slake

durability indices and average values of the various sample locations at the Questa mine.

 

45

4.3

3.0

2.2

4.3

3.64.0

2.8

4.5

0

1

2

3

4

5

6

7

8

9

0 1 2 3 4 5 6 7 8 9

POIN

T LO

AD

STR

ENG

HT

IND

EX (M

Pa)

LOCATION

Goathill North (31,1.85) Averages Middle (2,0.12)Spring Gulch (7,1.16) Sugar Shack South (8,0.79) Sugar Shack West (11,1.15)PIT (30,1.64) Debris Flow (12,0.99) Alteration Scars (4,0.83)

Extremely low to medium

High

Very high

Figure 2.9: Point load strength index values for the rock piles, alteration scars and debris flows. The average point load strength index for each location is shown with a red circle. The number of samples for each location and the standard deviation are shown in parentheses. PIT samples are unweathered drill core samples of andesite, intrusive (aplite) and rhyolite (Amalia Tuff) of various hydrothermal alteration intensities. See Figure 1.2 for location of rock piles. See Figures 1.2 and 1.3 for location of trenches and geologic units in GHN where samples were obtained. Appendix B summarizes the location and description of these samples.

 

46

96.1 96.9 96.197.4

96.395.3

98.4

89.2

60

65

70

75

80

85

90

95

100

0 1 2 3 4 5 6 7 8 9

SLA

KE

DU

RA

BIL

ITY

IN

DEX

(%)

LOCATION

Goathill North (76,3.19) Middle (3,1.10) Spring Gulch (8,5.15)

Sugar Shack South (30,2.97) Averages Sugar Shack West (15,4.05)

PIT (30,3.58) Debris Flow (18,0.93) Alteration Scars (24,9.22)

High durability

Very high durability

Extremely high durability

Figure 2.10: Slake durability index values for the rock piles, alteration scars, and debris flows. The average slake durability index for each location is shown with a red circle. The number of samples and the standard deviation for each location are shown in parentheses. PIT samples are unweathered drill core samples of andesite, intrusive (aplite) and rhyolite (Amalia Tuff) of various hydrothermal alteration intensities. See Figures 1.2 and 1.3 for location of rock piles and location of trenches and geologic units in GHN where samples were obtained. Appendix B summarizes the location and description of these samples.

Figure 2.11 shows the plots of different hydrothermal alterations verses slake and

point load indices. The point load values of drill core andesite samples (unweathered

samples) range from 1.3 to 6.9 MPa (Table 2.5), with all samples classified with high and

very high strength (Table 2.2); the rhyolite (Amalia Tuff) samples have slightly lower

point load indices (Fig. 2.12). The slake durability values for samples of relatively

weathered and unweathered aplite and rhyolite (Amalia Tuff) collected from outcrops

and drill core throughout the area, range from 88.9 to 99.5%, with all samples classified

 

47

as having high to extremely high durability (Table 2.6). There is no significant difference

in average slake durability and point load indices between different lithologies and

different alteration assemblages (Figs. 2.11, 2.12 and 2.13).

Figure 2.11: Variation in slake index, point load and alteration (QSP, Propylitic and Argillic) of the Questa rock materials. See Figure 1.2 for location of rock piles where samples were obtained. Appendix B summarizes the location and description of these samples.

 

48

2.6

3.7 3.6

0

1

2

3

4

5

6

7

8

0.0 1.0 2.0 3.0

POIN

T L

OA

D S

TR

EN

GT

H IN

DE

X (M

Pa)

LITHOLOGY

Amalia(3,0.7) Andesite(19,1.70) Intrusive(8, 1.73) Average

94.195.1

96.3

70

80

90

100

0 0.5 1 1.5 2 2.5 3 3.5

SLA

KE

DU

RA

BIL

ITY

IND

EX

(%)

LITHOLOGYAmalia(6, 3.1) Andesite(19, 3.4) Intrusive(10,2.7) Average

Figure 2.12: Point load strength index values for different lithologies (Amalia, Andesite and Intrusive) which are drill core samples. The average point load strength index for each lithology is shown with a red circle. The number of the samples and the standard deviation are shown in the parentheses. See Figure 1.2 for location of open pit. Appendix B summarizes the location and description of these samples.

Figure 2.13: Slake durability index values for different lithologies (Amalia, Andesite and Intrusive) which include the drill core and outcrop samples. The average slake durability index for each lithology is shown with a red circle. The number of samples for each location and standard deviation are shown in the parentheses. See Figure 1.2 for location of open pit. Appendix B summarizes the location and description of these samples.

 

49

The slake durability and point load indices of debris flow (average slake

durability index of 98.4% and point load index of 4.0 MPa) and the alteration scar

samples (average slake durability index of 89.2% and point load index of 2.8 MPa) are

relatively similar to the corresponding values of rock-pile samples (Tables 2.5, 2.6; Figs.

2.9, 2.10). Note that the debris flows and alteration scars were exposed to weathering

longer than the rock pile material.

There are no strong correlations between point load and slake durability with

mineralogy or chemistry (Fig. 2.14 and Appendix B).

 

50

Figure 2.14: Variations between slake durability index, point load index, mineralogy, and chemistry. The mineralogy and chemical analyses were performed on splits of the same sample set that were used in the geotechnical testing and represent the mineralogy and chemistry of the sample tested by geotechnical methods. See Figure 1.2 for location of rock piles. Appendix B summarizes the location and description of these samples.

Figure 2.15 shows a scatter plot of slake durability versus point load strength

indices of the Questa Mine materials. Samples with low values of point load index also

tend to have low values of slake durability index but not all samples (Fig. 2.15). Notice

that even though there is a positive correlation between the point load index and the slake

durability index, this correlation is not strong.

 

51

y = 0.2x - 16.6R² = 0.2

0

1

2

3

4

5

6

7

8

9

80 90 100

Point Load Strength In

dex (M

Pa)

Slake Durability Index %

The friction angle of the fine-grained soil matrix of samples collected, along with the

rock fragments tested for slake durability and point load indices, was obtained using a 2-

inch laboratory shear box (Gutierrez, 2006; Gutierrez et al., 2008). Shear tests were

conducted on the air-dried samples. There are no strong correlations between friction

angle and point load and slake durability indices of the Questa materials (Fig. 2.16).

Figure 2.15: Variation in slake index and point load index of the Questa rock materials.

 

52

Figure 2.16: Variations between slake durability index, point load index, friction angle, and residual friction angle. The friction angle was determined on the fine-grained matrix from the same location as the samples tested for slake durability and point load, which were determined on larger rock fragments. See Figure 1.2 for location of rock piles. See Figure 1.3 for location of trenches in GHN where samples were obtained. Appendix B summarizes the location and description of these samples.

Some weathered samples from the edge of GHN, other Questa rock piles, and analog

materials, show lower slake durability and point load indices than unweathered material;

but not all weathered samples have lower slake durability and point load indices. The

weathered samples exhibited a change in color, low paste pH, presence of jarosite,

gypsum, iron oxide minerals and Fe- soluble salts (often as cementing minerals), and low

abundance to absence of calcite, pyrite, and epidote in weathered samples, tarnish or

coatings of pyrite surfaces, dissolution textures of minerals, and chemical classification

as potential acid-forming materials using acid base accounting methods (as described

above and in Appendix B). Some samples with low paste pH, but not all, from the edge

 

53

of GHN, other Questa rock piles, and analog materials show lower slake durability and

point load indices (Fig. 2.17). Paste pH is an indication of weathering, as discussed

above, with lower paste pH suggesting more weathered material (McLemore et al.,

2008a). Figure 2.18 shows the variation of point load and slake indices with the simple

weathering index (SWI). No definite correlation is observed in this figure. This could

indicate that the main reason for observed variations of slakes durability and point load

indices are the pre-mining alteration, and that the weathering effects have been so far of

less significance. Comparison of the slake durability and point load indices of the

weathered (rock piles) and unweathered samples (samples from drill logs) confirms that

the overall intensity of the weathering in the last 25-40 years has not been significant to

result in noticeable decrease the strength of the Questa rock-pile materials.

 

54

Figure 2.17: Variation in slake index, point load index and paste pH of the Questa rock materials. See Figure 1.2 for location of rock piles. See Figures 1.2 and 1.3 for location of trenches and geologic unites in GHN where samples were obtained. Appendix B summarizes the location and description of these samples. The upper part of the figure is for the all the other rock pile location and the analogs except the GHN whereas the lower part is GHN.

 

 

 

55

 

Figure 2.18: Variation in slake index, point load and simple weathering indices (SWI) of the Questa rock materials. See Figure 1.2 for location of rock piles. See Figures 1.2 and 1.3 for location of trenches in GHN and geologic units where samples were obtained. Appendix B summarizes the location and description of these samples. The upper part of the figure is for the all the other rock pile location and the analogs excluding the GHN whereas the lower part is GHN.

2.6 Conclusions

The point load indices are medium to very high according to the point load

strength index classification (Fig. 2.9). The slake durability indices from the Questa rock

piles are high to extremely high according to the slake durability index classification (Fig.

2.10). Samples from the GHN rock-pile are similar in slake durability and point load

indices regardless of geologic layer and location within the rock pile, except that some,

but not all samples located in the outer, weathered edge of the rock pile (Units C and I)

 

56

that are weaker and have lower slake durability and point load indices. There is no

significant difference in slake durability or point load indices between different

lithologies or hydrothermal alterations, except the rhyolite samples that have slightly

lower point load indices (Figs. 2.12 and 2.13). The slake durability and point load test

results indicate that the debris flow and the alteration scar samples are relatively similar

to the range in values obtained for the rock-pile samples. The debris flows and alteration

scars represent the more weathered material that have occurred over thousands to

millions of years. Some weathered samples from the edge of GHN, other Questa rock

piles, and analog materials, show lower slake durability and point load indices than

unweathered material, but not all weathered samples have lower slake durability and

point load indices. There are no strong correlations between point load and slake

durability with mineralogy or chemistry (Fig. 2.14). Samples with low values of point

load index also tend to have low values of slake durability index, but not all samples (Fig.

2.15). A comparison statistic was conducted on the unweathered drill core samples with

the GHN rock-pile and the other rock-piles combined excluding GHN rock-pile

(Appendix C). There are no strong correlations between friction angle and point load and

slake indices of the Questa materials (Fig. 2.16). GHN rock pile samples have high

durability and strength even after having undergone hydrothermal alteration and blasting

prior to deposition and after potential exposure to weathering for about 25-40 years.

Collectively, these results suggest that future weathering (< 1000 years) will not

substantially decrease the strength indices of rock fragments of the rock piles.

 

57

3.0 CHARACTERIZATION OF QUESTA DEBRIS FLOWS

3.1 Introduction

The purpose of the Questa Rock Pile Weathering and Stability Project is to

develop a model to identify and assess conditions and processes occurring in existing

rock piles, especially related to the physical, chemical and mineralogical composition and

weathering of, rock pile materials at the Questa mine. The key question to be addressed

is, “Will the rock piles become gravitationally unstable over time?” One component of

this investigation is to estimate what changes in these conditions and processes, if any,

have occurred since construction of the rock piles, and thereby to extrapolate what future

changes might occur in these conditions and processes. As a result, it should be possible

to obtain the information necessary and sufficient to provide a scientific basis for

determining the effect of weathering on the geotechnical behavior of the rock piles as a

function of time and degree of weathering.

The extent of weathering in the rock piles is limited by their short exposure

history. One approach to determine the future changes of slope stability of the rock piles

is to examine analog materials for their composition, stability and strength. Analog

materials are from sites in the vicinity of the Questa mine that are similar in composition

and weathering process as the rock piles, but are older than the rock piles. Processes

operating in the natural analogs share many similarities to those in the rock pile, although

certain aspects of the physical and chemical system are different (Graf, 2008; Ludington

et al., 2004). The debris flows in the Questa area are identified as natural analogs for

 

58

future weathering of the rock piles, because they have undergone hydrothermal alteration,

weathering, and erosion since they were formed and could represent the future

weathering of the rock piles. The current approach, tests the geotechnical behavior of

samples across a range of weathering states that are defined by petrology, mineralogy,

and chemistry for samples collected from the existing rock piles and analog weathering

sites in the Questa-Red River area.

Hence, a debris flow profile was studied to determine if it can serve as a physical,

mineralogical and chemical analog or proxy to weathering and diagenesis of the Questa

rock piles, as well as to determine the weathering products of the debris flows and how

they relate to the point load strength index, slake durability index, and the friction angle

of the debris flows. The purpose of this study was 1) to describe the debris flow profile,

2) to determine if the cementation of the debris flows is similar to cementation found, or

expected to be found in the future, within the Questa rock piles, and 3) to determine how

cementation varies along the debris flow profile.

3.2 Definitions

The debris flows near the Questa mine are naturally occurring sedimentary

deposits that consist of similar lithologies as the Questa rock piles (Table 3.1;

hydrothermally altered andesite, rhyolite (Amalia Tuff), granitic and aplite intrusions).

The debris flows were formed by a mixture of sediment and water that flowed downhill

in a natural drainage, whereas the rock piles were formed by end dumping of relatively

dry, blasted rock material over the edge of a slope (McLemore et al., 2008a). Since the

 

59

stabilization of the debris flow it has been subjected to similar weathering processes as

the rock piles.

Weathering is the alteration that involves disintegration of rocks by physical, chemical,

and/or biological processes that result in the reduction of grain size, changes in cohesion

or cementation, and changes in mineralogical composition (McLemore et. al., 2008a).

According to the AGI Geologic Glossary (Neuendorf et al., 2005), weathering is “the

destructive process or group of processes by which earthy and rocky materials on

exposure to atmospheric agents at or near the earth’s surface are changed in color,

texture, composition firmness, of form with little or no transport of the loosen or altered

material; specifically the physical disintegration and chemical decomposition of rock that

produce an in-situ mantle of waste.” Many scientists study these processes in terms of

geologic time, occurring over thousands to millions of years. Weathering is simply the

consequence of exposing rocks to the conditions at the Earth’s surface as a result of fairly

low temperatures, low pressures, organic activity, and chemically active substances such

as water and the gases of the atmosphere. However, weathering in rock piles, including

the Questa project, is a study of weathering in engineering time, i.e. tens to hundreds of

years (<1000 yrs), where short-term weathering processes are more important than long-

term processes (Fookes et al., 1988; Geological Society Engineering Group Working

Party, 1995). Weathering profiles can provide the link between the short-term,

engineering time scale and the long-term, and geologic time scale.

Hydrothermal alteration is the change in original composition of rock in place by

hydrothermal (warm to hot) solutions during or after mineralization. In the Questa study,

hydrothermal alteration refers to pre-mining conditions. This includes hypogene

 

60

(primary) and supergene (secondary) alteration. Hypogene alteration occurred during the

formation of the ore deposit by upwelling, hydrothermal fluids. Supergene alteration is a

low-temperature natural weathering of the ore deposit that occurred near the Earth’s

surface before mining.

3.3 Background

A debris flow is defined as a mixture of sediment and water that flows in a

manner as if it was a continuous fluid driven by gravity, and it attains large mobility from

the large void space saturated with water or slurry (Tamotsu, 2007). There has been

extensive work on debris flows because of their disastrous nature, but very few debris

flow studies include slake durability and point load strength tests hence this study. Dick

and Shakoor (1995) stated that, debris flows are the likely mode of failure in mudrocks of

medium to low durability and tend to occur when developed regolith fails during heavy

rains and wet periods. Viterbo (2007) showed that slake durability and point load test

values indicate that, the rock fragments from the Goat Hill North (GHN) rock pile are

still quite strong even after being highly fractured and altered before being blasted, then

emplaced in the pile and subsequently weathered. This study is concentrated on the Goat

Hill (Goat Hill Gulch) debris flow, which contains material that is mineralogically and

chemically similar to the GHN rock pile and can be used as a proxy for long-term

weathering in the GHN rock pile.

The debris flows consist of similar rock lithologies and hydrothermal alteration,

and have been subjected to the same weathering environment as the rock piles. The

characteristics of the debris flows, alteration scars, and Questa rock piles are listed in

 

61

Table 3.1. There are important differences between each of these three types of

landforms; however, the majority of the parameters are similar between each category of

landform. The most significant difference between the rock piles and the debris flows is

the mechanism for deposition. The debris flows are deposited under saturated or near-

saturated conditions, which could lead to more sorting of particle sizes and more water

retention than the Questa rock piles, which were deposited under dry conditions.

The debris flows represent landforms that formed during the time between the

formation of relatively young Questa rock piles and the alteration scars of the Red River

valley. The exact ages of the debris flows are difficult to determine due to the episodic

nature of debris flow development. However, the estimated age of the debris flows in the

Red River area are as old as 100,000 years. A radiocarbon isotope date of a charcoal

sample from within the debris flow was determined to have an age of approximately 4917

years before present (Lueth et al., 2008). The charcoal appears to have formed during a

period of time where the debris flow was stable long enough to form a paleosoil, with

associated ponded water, to produce a charcoal layer (Lueth et al., 2008). The debris

flow cannot be older than the Goat Hill alteration scar, since the debris flow is composed

of material that was derived from the alteration scar, therefore the maximum age of the

debris flow cannot be more than 1.48 Ma (Lueth et al., 2008). The debris flow is older

than the open pit mine, because the mine administration buildings are built on it.

Point load strength and slake durability indices can provide a measure of rock

fragment strength. Point load and slake durability can indicate the degree of rock

fragment weathering by relating strength to the intensity of weathering; the strength of

rock fragments is related to the frictional resistance of the materials. The friction angle of

 

62

rock pile material is an important parameter in the characterization of rock pile stability,

because slope failure largely depends on this parameter.

Table 3.1: Index parameters for the rock-pile and analog materials QSP=quartz-sericite-pyrite. SP=poorly-graded sand, GP=poorly-graded gravel, SM=silty sand, SC=clayey sand, GW=well-graded gravel, GC=clayey gravel, GP-GC=poorly-graded gravel with clay, GP-GM=poorly-graded gravel with silt, GW-GC=well-graded gravel with clay, SW-SC=well-graded sand with clay, SP-SC=poorly-graded sand with clay.

Feature Rock Pile Alteration Scar Debris Flow Colluvium and weathered bedrock

Rock types Andesite Rhyolite

Aplite Porphyry Intrusion

Andesite Rhyolite

Aplite Porphyry Intrusion

Andesite Rhyolite

Aplite Porphyry Intrusion

Andesite Rhyolite

Unified soil

classification (USCS)

GP-GC, GC, GP-GM, GW, GW-GC, SP-SC, SC, SW-

SC, SM

GP-GC, GP GP, SP, GP-GC GP-GC, GP

% fines 0.2-46 Mean 7.5 Std Dev. 6

No of Samples=89

0.6-20 Mean 5.2 Std Dev. 4 No of Samples=18

0.3-6 Mean 1.8 Std Dev. 2 No

of Samples=12

3-40 Mean 20 Std Dev. 11

No of Samples=30 Water content (%) 1-24

Mean 10 Std Dev. 4 No of Samples=390

1-20 Mean 9 Std Dev. 4 No of Samples=48

1-29 Mean 5 Std Dev. 4 No of Samples=36

9-26 Mean 14 Std Dev. 3 No of Samples=13

Paste pH 1.6-9.9 Mean 4.8 std dev 1.9 No of samples=1368

2.0-8.3 Mean 4.3 std dev 1.6 No of samples=215

2.0-6.9 Mean 4.5 std dev 1.3

No of samples=58

2.4-8.6 Mean 3.8 std dev 1.3

No of samples=45 Pyrite content (%) Low to high

0-14% (mean 1.0%; std dev. 1.2%,

No of samples=1098)

Low to high 0-11%

(mean 0.7%, std dev 1.8%, No of samples=62)

Low to medium 0-0.2%

(mean 0.03%, std dev 0.06%,

No of samples=22)

Low to high 0-5.1%

(mean 0.4%, std dev 1.1%,

No of samples 26) Dry density kg/m3 1400-2400

Mean 1800 Std Dev. 140 No of Samples=153

1500-2300 Mean 1900 Std Dev. 210

No of Samples=13

1300-2200 Mean 1900 Std Dev. 340

No of Samples=10

2200 No of Sample=1

Particle shape Angular to subangular to subrounded

Subangular Subangular to subrounded Subangular to subrounded

Plasticity Index (%)

0.2-20 Mean 10 Std Dev. 5 No of Samples=134

5-25 Mean 12 Std Dev. 5 No of Samples=30

3-14 Mean 7 Std Dev. 3 No of Samples=18

5-23 Mean 13 Std Dev. 5 No of Samples=17

Degree of chemical

cementation (visual

observation)

Low to moderate (sulfates, Iron oxides)

Moderate to high (sulfates, Iron oxides)

Moderate to high (sulfates, Iron oxides)

Moderate to high (sulfates, Iron oxides)

Slake durability index (%)

80.9-99.5 Mean 96.6 Std Dev. 3.1

No of Samples=132

64.5-98.5 Mean 89.2 Std Dev. 9.2

No of Sample=24

96.1-99.6 Mean 98.4 Std Dev. 0.9

No of Samples=18

93-98.5 Mean 95.7 Std Dev. 1.7

No. of Samples= 9 Point Load index

(MPa) 0.6-8.2

Mean 3.8 Std Dev. 1.7 No of Samples=59

1.7-3.8 Mean 2.8 Std Dev. 0.8

No of Samples=4

2.6-6 Mean 4 Std Dev. 1 No of Samples=12

Not determined

Peak friction angle (degrees), 2-inch shear box (NMIMT data)

35.3-49.3 Mean 42.2 Std Dev. 2.9 No

of Samples=99

33.4-54.3 Mean 40.7 Std Dev. 4.8 No

of Samples=22

39.2-50.1 Mean 44.3 Std Dev. 3.9

No of Samples=12

36.9-46.1 Mean 41.4 Std Dev. 2.5

No of Samples=22

Average cohesion 0-25.9 12.1-23.9 31.4-46.1 Not determined

 

63

Feature Rock Pile Alteration Scar Debris Flow Colluvium and weathered bedrock

(kPa), in-situ shear tests

Mean 9.6 Std dev 7.3 No of samples=20

Mean 18.1 No of samples=2

Mean 38.8 No of samples=2

3.4 Sampling and analytical methods

A detailed mineralogical, chemical, and geotechnical study of a profile in the

Goat Hill debris flow along NM Highway 38 documents the changes in weathering

within this depositional environment. Samples were collected within the debris flow at

different elevations to examine the different degrees of weathering, diagenesis, including

cementation, and alteration with depth along the profile (Fig. 3.1). The samples were

characterized using several different analytical methods that were similar to those used to

examine the Questa rock piles. Point load, slake durability, and laboratory direct shear

tests were performed on the samples, and sampling procedures (Viterbo, 2007; SOP 24),

descriptions and analytical procedures for soil profiles were used (URS Corporation,

2003; Smith and Beckie, 2003). A standardized protocol was followed after each sample

was taken. Each sample was clearly identified and a chain of custody process was

followed to assure that all samples were transported to the laboratory, analyzed, and the

results sent back to New Mexico Bureau of Geology and Mineral Resources (NMBGMR)

at the New Mexico Institute of Mining and Technology (NMIMT). The samples were

transported from the field to NMBGMR and stored in a locked trailer until they could be

analyzed. Specific details for quality control and quality assurance are described in the

project SOPs (Table 3.2).

Samples for chemical analyses were crushed in a jaw crusher and pulverized by a

tungsten-carbide disc grinder to a particle size of <35 μm. Each sample was homogenized

 

64

at each crushing step by cone and quarter method. The samples were then sent to the

laboratories for analyses. NMBGMR internal (waste rock pile, rhyolite, basalt) and

commercially certified standards and duplicates of selected samples were submitted blind

to the laboratories with each sample batch of 25 samples to assure analytical quality;

NMBGMR has archived a split of all remaining samples for future studies. Laboratory

analyses were performed on the samples according to project SOPs, summarized in Table

3.2. Petrographic analyses (mineralogy, lithology, hydrothermal alteration) were

performed on both the soil matrix and rock fragments using a binocular microscope;

these analyses were supplemented by thin section analyses, microprobe analyses, X-ray

diffraction (XRD) analyses, and whole-rock chemical analyses using X-ray fluorescence

(XRF). Clay mineralogy, in terms of the major clay mineral groups, was performed on

the complete sample (i.e. both matrix and rock fragments) using standard clay separation

techniques and XRD analyses of the clay mineral separate on an oriented glass slide

(Hall, 2004; Moore and Reynolds, 1989). However, this method does not liberate or

measure the amount of clay minerals within the rock fragments. The concentrations of

major and trace elements of the complete sample, except S, SO4, C, LOI (loss on

ignition), and F were obtained by XRF spectroscopy at the New Mexico State University

and Washington State University laboratories. F concentrations were determined by ion

probe at NMIMT and LOI concentrations were determined by gravimetric methods at

NMIMT. Leco Furnace determined total S and C, and SO4 was determined by sulfate

sulfur-carbonate leach by ALS Chemex. S as sulfide was determined by subtracting SO4

from the total S.

 

65

Table 3.2: Summary of sample preparation for specific laboratory analyses for samples collected from the weathering profile. XRF–X-ray fluorescence analyses, XRD–X-ray diffraction analysis, slake durability tests, point load tests.

Laboratory analysis Type of sample Sample Preparation Method of obtaining accuracy and precision

SOP

Whole-rock chemical analysis (XRF, S/SO4)

Collected in the field in separate bag

Crushed and pulverized

Use reference standards and duplicates and triplicates

8

Whole-rock chemical analysis (ICP)

Collected in the field in separate bag

Crushed, pulverized, and dissolved in a liquid for analysis

Use reference standards and duplicates and triplicates

8, 30, 31

Atterberg Limits Bulk sample collected in the field

Sample sieved to <0.425 mm

Use duplicate analysis, compared to other results performed by consultant companies

54

Direct Shear Test (friction angle)

Bulk sample collected in the field

Sample sieved to <4.75 mm (for 2 inch shear test)

Use duplicate analysis, compared to other results performed by consultant companies

50

Particle-size analysis Bulk sample collected in the field

Sample sieved each size fraction weighed

Use duplicate analysis, compared to other results performed by consultant companies

33

Paste pH and paste conductivity

Collected in the field, used split from chemistry sample or gravimetric sample

Uncrushed, typically smaller than gravel size material used

Use duplicates, compared with field measurements using Kelway instrument (SOP 63), compare to mineralogical analysis

11

Gravimetric moisture content

Collected in the field in a sealed metal canister

Uncrushed, typically smaller than gravel size material used

Use duplicates 40

Petrographic analyses Collected in the field, used split from chemistry sample

Uncrushed, typically smaller than gravel size material used, thin sections made of selected rock fragments

Selected samples were analyzed by outside laboratory

24

Microprobe analyses Collected in the field or split from chemistry sample

Uncrushed, generally 2 splits; rock fragments and soil matrix

Use reference standards 26

X-ray diffraction (XRD) analyses (including remaining pyrite analysis)

Used split from chemistry sample

Crushed Compared to detailed analysis by electron microprobe

27, 34

Clay mineralogy analyses

Used split from chemistry sample

Uncrushed, typically smaller than gravel size material used, thin sections made of selected rock

Use duplicate analysis, compared to other results performed by consultant companies, compared to detailed

29

 

66

Laboratory analysis Type of sample Sample Preparation Method of obtaining accuracy and precision

SOP

fragments, clay separation obtained by settling in a beaker of DI water

analysis by electron microprobe

Point Load tests Rock fragments tested sizes were around 50 ± 35mm with the ratio of D/W between 0.3 and 1.0

none Multiple testing and average is determined.

77

Slake durability tests Rock fragments 40 and 60 g (approximately 4-10 cm in dimension)

The rock pieces are brushed to remove all the accumulated dust on it prior to weighing.

Duplicate tests 76

3.5 Description of the debris flow profile

Samples were collected from the debris flows from different beds. The sizes of

the samples ranged from fine silt to boulders, sub-angular to sub-rounded in shape, and

some of the samples were well graded, while others were poorly graded gravel. The

colors were mostly brown with the exception of one sample that was light reddish brown

and the cementation ranged from moderately to strong cemented (Table 3.3). The profile

studied is not a typical weathered profile since there is no systematic variation in the

composition of the samples collected from the profile, indicating that the debris flow was

formed in several different events with slightly different sources.

The samples were collected from within 57 ft of UTM easting 452331 and

northing 4059891. Figure 1.2 shows the location of the debris flow and Figure 3.1 shows

a view of the profile looking straight at the debris flow on the highway 38. Table 3.3

shows the description of samples collected. In-situ tests were conducted at the surface of

this debris flow and those samples and test were described by Boakye (2008) and

McLemore et al. (2008b). Nunoo (2009) and Nunoo et al. (2009) also described detailed

 

67

studies on the particle shape and geotechnical characterization of a sample from this

locality.

Figure 3.1: Photograph of Goat Hill debris flow. Boxes show location of collected samples. Collected samples consist of a bulk grab of rock material stored in 5 gallon buckets and includes matrix (soil) and rock fragments.

Table 3.3: Description of the debris flow profile. Depth

interval (ft)

Grain Size

Color Grain angularity Sedimentary structure

Description Cementation Sample collected

2 Boulders to clay

Brown Subangular-subrounded

Massive Well graded Moderate MIN-GFA-0001

3 Boulder to clay

Brown subangular Massive Well graded Moderate MIN-GFA-0003

6.4 Boulder to clay

Brown Subangular-subrouned

Massive Well graded Strong MIN-GFA-0005

12 Gravel to fine silt

Brown subangular Massive Poorly graded gravel

Strong MIN-GFA-0006

13 Cobble to fine silt

Angular to subangular

Massive Poorly graded gravel

Moderate MIN-GFA-0007

27 Coarse gravel to sandy

Light redish brown

Angular to subangular

Massive Well MIN-GFA-0009

 

68

3.6 Results

Table 3.4 is a summary result of the geological and geotechnical parameters for

the profile. The results of the chemical and mineralogical compositions of the samples are

in Tables 3.5 and 3.6, respectively.

Table 3.4: Geological and geotechnical parameters of samples collected from the debris flow profile. Samples MIN-GFA-0006 and MIN-GFA-0007 did not contain rock fragments but rather soils materials due to the nature of the samples, point load and slake durability tests were not performed on them. Sample MIN-GFA-

0001 MIN-GFA-

0003 MIN-GFA-

0005 MIN-GFA-

0006 MIN-GFA-

0007 MIN-GFA-

0009 Paste pH 3.20 3.87 3.24 3.90 3.55 3.58 Paste Conductivity (mS/cm)

0.44 0.14 0.22 0.13 0.19 0.21

Water Content % 1.1 4.4 13.2 13.2 5.8 7.0 Geotechnical Parameters

Slake Index % 98.4 99.5 98.7 98.6 Point Load MPa 2.8 6.0 2.6 3.8 Dry Density g/cm3 2.19 1.33 1.51 1.51 1.17 2.09 Friction Angle (degrees)

50.0 45.7 39.2 40.3 44.5 45.2

Residual Friction Angle (degrees)

37.8 33.8 34.9 34.8 36.0 35.5

Atterberg Limit Liquid Limit % 24.8 28.2 25.5 24.6 Plastic Limit % 18.7 19.3 18.8 21.6 Plastic Index % 6.2 8.9 6.8 3.1 Particle Size Distribution

Gravel % 69.6 65.3 69.3 45.5 28.2 59.5 Sand % 30.1 33.7 29.9 51.7 70.0 39.3 Silt % 0.3 0.9 0.9 2.8 1.8 1.2 Clay % Fines % 0.3 0.9 0.9 2.8 1.8 1.2 D10, mm 0.9 0.9 0.7 0.2 0.3 0.8 D30, mm 4.8 4.0 4.5 1.4 1.1 3.2 D50, mm 20.0 10.0 18.0 4.0 6.2 D60, mm 23.0 15.0 30.0 5.8 3.6 8.6

 

69

Table 3.5: Chemical composition of samples collected from debris flow profile. Oxides are in weight percent and trace elements are in parts per million.

Sample MIN-GFA-0001

MIN-GFA-0003

MIN-GFA-0005

MIN-GFA-0006

MIN-GFA-0007

MIN-GFA-0009

SiO2 72.65 70.88 73.70 70.03 73.95 74.70 TiO2 0.50 0.46 0.39 0.51 0.41 0.40 Al2O3 13.17 12.98 13.2 12.97 12.92 12.50 FeOT 2.22 3.26 1.92 3.81 2.06 2 MnO 0.22 0.39 0.02 0.04 0.02 0.02 MgO 0.79 1.23 0.68 1.27 0.67 0.6 CaO 0.1 0.71 0.02 0.56 0.05 0.06 Na2O 0.62 1.07 0.46 1.65 0.58 0.57 K2O 4.31 3.53 4.19 3.41 4.00 4.03 P2O5 0.10 0.18 0.09 0.19 0.11 0.13

S 0.05 0.09 0.05 0.05 0.02 0.03 SO4 0.21 0.07 0.25 0.17 0.28 0.23

S/SO4 0.24 1.29 0.20 0.29 0.07 0.13 C 0.02 0.03 0.01 0.08 0.04 0.03

LOI 3.46 2.91 3.68 3.95 3.80 3.42 Total 98.65 98.11 98.86 99.06 99.12 99.30 Ba 642 822 613 871 666 591 Rb 149 104 149 104 134 137 Sr 133 280 138 265 140 145 Pb 70 32 103 51 98 47 Th 13 8 12 8 13 11 U 5 6 4.5 4.00 5.00 5.00 Zr 215 172 240.50 189.00 226.00 213.00 Nb 24.00 16.90 25.50 16.20 24.10 24.00 Y 32.00 23.00 40.00 21.00 35.00 33.00 Sc 5.00 6.00 4.00 7.00 5.00 5.00 V 61 62 46 73 46 44 Ni 5 14 1 12 1 1 Cu 24 37 17 45 19 26 Zn 25 68 21 50 21 23 Ga 20 17 22 21 19 Cr 42 43 27 53 29 30 F 1281 1045 1416 1116 1448 1737 La 47 29 50 34 46 46 Ce 95 57 98 63 98 91 Nd 41 25 41.5 24 41 37

 

70

Table 3.6: Mineral composition of samples collected from debris flow profile, in weight percent (as determined by quantitative mineralogy method from the modified ModAn method, McLemore et al., 2009). QSP=quartz, pyrite, sericite alteration and QMWI= Questa mineral weathering index (McLemore et al 2008a) Sample MIN-GFA-

0001 MIN-GFA-

0003 MIN-GFA-

0005 MIN-GFA-

0006 MIN-GFA-

0007 MIN-GFA-

0009 SWI 3 3 3 3 illite 28 25 28 21 29 27 chlorite 2 3 1 3 2 1 smectite 1 1 2 1 1 1 kaolinite 2 2 3 2 2 Pyrite 0.1 0.2 0.1 0.1 0.1 Gypsum 0.01 0.3 0.04 0.8 0.1 0.1 Jarosite 1 0.01 1 1 Othoclase 18 16 20 17 14 16 Quartz 45 43 46 40 48 48 QSP 65 85 70 55 70 70 Argilic 5 10 Intrusive 99 Amalia 1 99 10 10 100 Andesite 100 2 90 90 Proplytic 2 7 QMWI 7 2 7 7 7 7

3.7 Discussion

The geotechnical parameters do not show a clear trend with depth (Figs. 3.2 and

3.3). The point load and slake durability values for the debris flow profile are within the

ranges found in the Questa rock piles (Table 3.1). There is no observed clear trend of

slake durability index and point load strength index with depth, which might be due to the

deposition of different material layers during the formation of the debris flow which was

observed during sampling (Fig. 3.2). The paste pH, paste conductivity, moisture content

and dry density do not appear to correlate with depth (Fig. 3.3). Note the dry density of

samples located in the deeper layers is higher.

 

71

Figure 3.2: Variations of slake index, friction angle, and point load index and percent gravel with depth from the base of the debris flow profile. No observed trend of parameters with depth.

The water content of the samples from within the profile range between 1.1 and

13.2% and are slightly lower than the moisture contents of the Questa rock piles. The

gradation curves for the samples are shown in Fig. 3.4. The low percentage of fines in the

samples may be the result of clay-size particles remaining as larger silt- to sand-sized

aggregates during the dry sieving process. The sample with the highest peak friction

angle (MIN-GFA-0001) also has the highest percentage of gravel, contained angular rock

 

72

fragments, and has the highest dry density (Table 3.4). The high friction angle of this

sample is likely the result of these combined factors.

Figure 3.3: Variations of paste pH, paste conductivity, water content and dry density with depth from the base of the debris flow profile. No clear trend was observed between the parameters and depth.

 

 

73

0102030405060708090

100

0.0010.010.1110100

Perc

ent P

assi

ng b

y W

eigh

t

Grain Size, mm

Particle Size Distribution

MIN-GFA-0001 MIN-GFA-0003 MIN-GFA-0005 MIN-GFA-0006 MIN-GFA-0007 MIN-GFA-0009

COBBLE GRAVEL SAND SILT CLAY

BOULDER

Coarse Fine Coarse Medium Fine

Hydrometer3/83 41.5 1 103/4 16 30 40 50 60 200100

U.S. Standard Sieve Size

2 6

Figure 3.4: Gradation curves for the sieve analysis on the individual samples from the debris flow profile.

There are no clear trends within the debris flow profile to indicate an increase in

weathering with depth in the profile. The results of the geochemical characterization

indicate that, samples collected from the debris flow are similar to each other and do not

indicate decrease in weathering from the top of the profile to the bottom. The paste pH

values for all of the samples range from 3.2 to 3.9, but there is no clear trend with depth

(Table 3.4 and Fig. 3.3). There is no clear trend of total Fe-oxide, Fe-oxide minerals, K-

feldspar, plagioclase or other minerals with depth (Figs. 3.5 and 3.6). There is no clear

trend of some selected trace elements such as fluorine, lead, copper and zinc with depth

(Fig. 3.7). The sulfide to sulfate ratio does not indicate an increase in sulfate minerals

with increasing depth; with the exception of the sample towards the middle of the profile

showing a relative decrease in the abundance of sulfate minerals towards the middle of

 

74

the debris flow (Figs. 3.8 and 3.9). This could indicate rapid deposition of the material to

prevent the oxidation of sulfide minerals. This could also be an indication of increase

sulfate mineralogy in the material before weathering. However, the total S amount for

this sample is slightly lower than the other samples from the debris flow. There is no

clear trend of mineralogy and pyrite with depth (Fig. 3.10). The mineralogy and

chemistry are similar to the samples at the in-situ test sites at the top of the debris flow

(McLemore et al., 2008).

Figure 3.5: Variations of FeO and Fe oxide minerals with depth from the base of the debris flow profile. No clear trend of parameters with profile.

Figure 3.6: Variations of total feldspar (K-feldspar+plagioclase) with depth from the base of the debris flow profile. No clear trend of parameters with profile.

 

75

0

5

10

15

20

25

30

0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4

Dept

h (ft

)

S/SO4

Figure 3.7: Variations of selected trace elements with depth from the base of the debris flow profile. No clear trend of trace elements with profile.

Figure 3.8: Variations of sulphur and SO4 with depth from the base of the debris flow profile. No clear trend of parameters with profile.

Figure 3.9: Variations of sulphur/sulphate ratio with depth from the base of the debris flow profile. No clear trend of sulphur/sulphate with profile.

 

76

Figure 3.10: Variations of geochemical and mineralogical parameters on the X-axis and sample location along the profile from base to top on the y-axis. No clear trend of parameters with profile.

0

5

10

15

20

25

30

20 21 22 23 24 25 26 27 28 29 30

Dep

th (f

t)

Illite (%)

0

5

10

15

20

25

30

39 40 41 42 43 44 45 46 47 48 49

Dep

th (f

t)

Quartz (%)

0

5

10

15

20

25

30

0 1 2 3 4

Dep

th (f

t)

Chlorite (%)

0

5

10

15

20

25

30

0 0.05 0.1 0.15 0.2 0.25

Dep

th (f

t)

Pyrite (%)

0

5

10

15

20

25

30

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9

Dep

th (f

t)

Gypsum (%)

0

5

10

15

20

25

30

10 12 14 16 18 20 22

Dep

th (f

t)

Orthoclase (%)

 

77

The clay mineralogy from X-ray diffraction (XRD) analyses indicates that the

samples from the debris flow profile contain the same clay mineral groups as the Questa

rock piles and the alteration scar samples. The samples from the debris flow contain illite,

kaolinite, smectite, and minor chlorite (Fig. 3.11). The clay mineral relative abundances

do not vary significantly along the profile. The XRD peak position of the smectite clay

minerals indicate that the smectites contain only one structural water interlayer similar to

the smectites found in the Goathill north rock pile (Donahue et al., 2008). Jarosite is

present in all of the clay samples.

Figure 3.11: Clay mineralogy XRD scans for the debris flow weathering profile. I = illite, C = Chlorite, S = smectite, K = kaolinite, J = Jarosite.

Weathering and diagenic processes (especially cementation) have occurred in the

debris flow, which is similar to that found in the rock piles (Figs. 3.12, 3.13, 3.15 and

 

78

3.16). Figures 3.13 and 3.14 shows the similarity in texture and mineralogy of the

cementation found in the debris flow and with the GHN rock pile and is formed by

oxidation of sulfide minerals producing sulfates and iron oxides. The debris flows are

well cemented, even below the surface. Portions of the Questa rock piles are poorly

cemented or have no cementation, but other portions, especially the outer layers are

moderate to well cemented (Table 3.1). This cementation is formed through the presence

of clay minerals, which are acting as cementing agents in the debris flow. Also break

down of pyrite produces sulfur which binds with iron and potassium to form jarosite,

gypsum, iron oxides and clay minerals. Cementation is variable in the profile and is

attributed to the precipitation of gypsum, jarosite, and Fe-oxide minerals (Fig. 3.17).

 

79

Figure 3.12: Backscattered electron microprobe image showing a cemented grain consisting of small hydrothermally-altered phenocrysts within MIN-GFA-0001 sample. The cement consists of clay minerals (illite), jarosite, and Fe oxides. The numbered points represent points for mineral chemistry.

Figure 3.13: Backscattered electron microprobe image showing well cemented grains of hydrothermally-altered phenocrysts within MIN-GFA-0001 sample. Illite, jarosite and Fe oxide crystals are cementing the rock fragments. The cementation is similar in chemistry and texture as that found in the GHN rock pile. The numbered points represent points for mineral chemistry.

 

80

Figure 3.14: Backscattered electron image (BSE) of a soil sample from GHN rock pile showing rock fragment and associated fine-grained matrix material. Note the similarity in texture of the cementation of rock fragments in this image compared to the image in Figure 3.13. The fine-grained matrix consists of clay minerals and gypsum. .

GHN-KMD-0065-30-01

 

81

Figure 3.15: Backscattered electron microprobe image showing well-cemented hydrothermally-altered phenocrysts within MIN-GFA-0006 sample. Illite, jarosite, Fe oxide and feldspar crystals are cementing the rock fragments. The numbered points represent points for mineral chemistry.

Figure 3.16: Backscattered electron microprobe image showing hydrothermally-altered phenocrysts within MIN-GFA-0006 sample. Illite, jarosite, Fe oxide and kaolinite crystals cementing the rock fragments. The numbered points represent points for mineral chemistry.

 

82

Figure 3.17: Sample location along the profile, sample photos and microprobe images along with sample type and strength of cementing agents.

 

83

3.8 CONCLUSIONS

• The debris flows are similar to the Questa rock piles in terms of lithology, slake

and point load indices, friction angle, particle size distribution. However, the

cohesion intercept values of the of the debris flow are higher than those of the

rock piles (Boakye, 2008). The profile studied is not a weathered profile. There

are no systematic variations in the composition of the samples collected from the

profile, indicating that the debris flow was formed by several different flood

events with slightly different sources.

• There are no clear trends within the debris flow profile to indicate an increase in

weathering with depth in the profile. The results of the geochemical

characterization indicate that the samples collected from the debris flow are

similar to each other and do not show signs of decreasing weathering from the top

of the profile to the bottom.

• The paste pH values for all of the samples range from 3.2 to 3.9, however there is

no clear trend with depth (Table 3.4).

• The clay mineralogy from X-ray diffraction (XRD) analyses indicates that the

samples from the profile contain the same clay mineral groups as the Questa rock

piles and the alteration scar samples. The samples from the debris flow contain

illite, kaolinite, smectite, and minor chlorite (Fig. 3.11).

• The results of the geotechnical testing indicate that, there is no clear trend of

decreasing strength with increasing depth for the samples from the debris flow

profile. The point load and slake durability values for the debris flow profile are

within the ranges found in the Questa rock piles (Table 3.1). The water contents

 

84

of the samples from within the profile range between 1.1 and 13.2 % and are

slightly lower than the moisture contents of the Questa rock piles (Tables 3.1 and

3.4).

• The sample with the highest peak friction angle (MIN-GFA-0001) also has the

highest percentage of gravel, contained sub-angular rock fragments, and highest

dry density (Table 3.4). The high friction angle of these samples is likely a result

of these combined factors.

• The cementation agents are similar to those found in the rock piles are formed by

oxidation of sulfide minerals producing sulfates and iron oxides. The debris flows

are well cemented, even below the surface. Distribution of sulfide and sulfate

minerals suggests an open-system behavior (i.e. movement of sulfur within the

debris flow). No trends in silicate minerals (including clays) suggest that, no new

silicate minerals are forming during weathering, similar to observations in the

rock piles.

 

 

85

4.0 HOT ZONE STRENGTH STUDY.

4.1 Introduction

Venting gases or water vapor have been observed from several sites at the Questa

mine, mostly from drill holes in the front rock piles (Fig. 4.1), a vent area on Sulfur

Gulch South rock pile, and from cracks at the surface of Goathill North rock pile (GHN)

prior to regarding. Air flow was observed from coarse layers in GHN during examination

of the trenches (McLemore et al., 2008a). Elevated temperatures and relative humidity

explain these venting gases, often called fumaroles, which are common at other mine

sites (Ritchie, 2003; Wels et. al., 2003). Oxidation of pyrite is likely producing these hot

zones. Recent experimental studies by (Jerz 2002; Jerz and Rimstadt, 2004) have

confirmed earlier work by Morth and Smith (1966) that shows that, pyrite oxidizes faster

in moist air than under saturated conditions, thereby accelerating the weathering of the

rock piles, at least locally and producing hot spots. Shaw et al. (2003) described the

results of one years’ monitoring of temperature, CO2, and O2 from instrumented drill

holes in the rock piles at the Questa mine (Robertson GeoConsultants, Inc., 2000).

The purpose of this chapter is to summarize the strength of samples from the Sugar

Shack South hot zones using slake durability tests and determine whether weathering in

the hot zones will affect slope stability.

 

86

Figure 4.1: Location of venting drill holes and surface vent area. Blue indicates drill holes drilled in 1999 that contain monitoring instruments for temperature, O2 and CO2. Red indicates drill holes and surface vent area that do not contain temperature and gas instrumentation and are sites monitored by the New Mexico Tech team.

4.2 Background

Rock piles from porphyry copper and molybdenum mines are large accumulations

of generally coarse-grained material containing sulfides (mostly pyrite) that are usually

unsaturated (i.e. gaseous and liquid phases are simultaneously present in the pore space

between the solid grains). Initially, following the oxidation of the sulfides, a partial

depletion of the oxygen present in rock piles occurs, unless oxygen is being replenished

by air flow from outside the rock pile. Oxygen concentration gradients are thus created

between the gas phase within the pile and the atmospheric air surrounding the pile. This

oxygen concentration gradient drives gaseous oxygen diffusion from the surface to the

 

87

interior of the rock pile. Gaseous diffusion is a major process providing oxygen within

rock accumulations after their initial placement and convection and diffusion remains

active thereafter as long as the oxidation process contributes to the depletion of oxygen

concentration in the gas phase within the rock pile (Morin et al., 1991).

The release of heat from pyrite oxidation drives temperature up locally within

rock piles. This increase in temperature can completely modify the mechanism

responsible for oxygen transfer in the piles. Following an initial increase in temperature

in rock piles of sufficiently high air-permeability, temperature and density-driven gas

convection currents are initiated in the rock piles. The resulting advective transport

‘draws’ atmospheric air into the rock piles. Convection is a much more efficient oxygen

transfer process than diffusion. Barometric pumping is another mode of air transport in

rock piles (Wels et al., 2007). Wels et al. (2003) mentions that changes in barometric

pressure are known to affect air flow into rock piles. However, this mechanism has not

been fully investigated.

Viterbo (2007) and Viterbo et al. (2007) studied the Goathill North (GHN) rock

pile and stated that the slake durability and point load test values show that the rock

fragments from the GHN rock pile are still quite strong even after being highly fractured

and altered before being blasted, then emplaced in the pile and subsequently weathered.

Ayakwah et.al. (2009) also studied the durability of rock fragments from the Questa Mine

and stated that the rock fragments are still durable after they have been expose to

weathering.

 

88

4.3 Methods

The test methods used for this work are slake durability and point load. These

tests provide durability and strength of the rock fragments from the hot zone of Sugar

Shack South rock pile. Test methods procedure is in chapter 2 section 2.3.2.

4.4 Results

The individual slake durability and the point load strength indices are shown in

Table 4.1 and 4.2 respectively. There are only 2 point load results and this is because the

samples were collected from drill cutting and most of the samples did not have enough

large rock fragments to perform the test on. Other results used were tests performed by

other members of the team (McLemore et al., 2008).

Hot zones were found in the Questa rock piles with temperatures ranging between

0° and 75°C. Cross sections were compiled through the Questa rock piles using available

data (Fig. 4.2).

Atterberg Limit values are in Table 4.3. There are no significant differences in

Atterberg Limits in the hot zone in drill hole SI-50. The slake durability indices remained

quite high except one result with an index of 39.7 % which is considered an outlier.

However LL, PL, and PI decrease below the hot zone.

 

89

SI-50Temperature versus Depth

-450

-400

-350

-300

-250

-200

-150

-100

-50

0

15 20 25 30 35 40 45 50 55 60 65

Temperature (Celcius)

Dep

th F

rom

Top

of C

asin

g (ft

)

Maximum OperatingTemperature 50o C

Figure 4.2: Temperature log of drill hole SI-50 from Sugar Shack South rock pile. Table 4.1: Slake durability indices for samples in drill hole SI-50 from Sugar Shack South and their individual classification (Franklin and Chandra, 1972). Sample ID Slake index (%) Durability Classification SSS-EHP-0001 98.34 Extremely high SSS-EHP-0002 98.45 Extremely high SSS-EHP-0003 98.87 Extremely high SSS-EHP-0006 98.38 Extremely high SSS-EHP-0011 98.66 Extremely high SSS-EHP-0012 98.27 Extremely high SSS-EHP-0014 99.13 Extremely high SSS-EHP-0015 99.28 Extremely high SSS-EHP-0017 99.16 Extremely high SSS-EHP-0019 99.18 Extremely high SSS-EHP-0020 97.28 Extremely high SSS-EHP-0021 96.16 Extremely high SSS-EHP-0025 98.95 Extremely high SSS-EHP-0025 39,7 Low SSS-EHP-0029 99.32 Extremely high SSS-EHP-0030 99.54 Extremely high SSS-EHP-0031 99.28 Extremely high SSS-EHP-0032 99.52 Extremely high SSS-EHP-0033 99.35 Extremely high SSS-EHP-0034 99.50 Extremely high SSS-EHP-0036 99.13 Extremely high

 

90

Table 4.2: Point load strength indices for samples in drill hole SI-50 from Sugar Shack South and their strength classification. (Broch and Franklin, 1972). Most of the samples did not have big rock fragments for the point load test since the samples were collected from drill cutting. Sample ID Point load Index (MPa) Strength Classification

SSS-EHP-0014 2.45 High

SSS-EHP-0016 3.79 Very high

Table 4.3: Atterberg Limits through drill hole SI-50 from Sugar Shack South (URS, 2003). Sample ID LL PL PI

SSS-EHP-0003 20 17 3

SSS-EHP-0005 28 17 11

SSS-EHP-0007 24 17 7

SSS-EHP-0009 32 16 16

SSS-EHP-0011 26 15 11

SSS-EHP-0012 27 14 13

SSS-EHP-0013 30 14 16

SSS-EHP-0014 27 19 8

SSS-EHP-0016 28 17 11

SSS-EHP-0017 33 19 14

SSS-EHP-0018 31 18 13

SSS-EHP-0019 36 20 16

SSS-EHP-0020 32 17 15

SSS-EHP-0032 26 15 11

SSS-EHP-0036 21 16 5

SSS-EHP-0040 23 18 5

SSS-EHP-0042 29 21 8

 

91

4.5 Discussion

There is no significant differences in slake durability, Atterberg limits and the

mineralogy values from the test results (Figs. 4.3, 4.4, 4.5). There is no significant change

in paste pH within the hot zones (Fig. 4.3).

Variations in clay mineralogy with depth in SI-50 are shown in Figure 4.5. The

feldspar and clay mineral abundances do not change significantly in the hot zones. In

particular, kaolinite does not increase in relative abundance in the hot zones of the drill

holes. The concentration of gypsum + jarosite increases (Fig. 4.5). Plot of variations of

K-feldspar, gypsum+jarosite, total clay minerals with slake indices are shown in Figure

4.6.

 

92

Figure 4.3: Variations in slake durability index and paste pH with depth in drill hole SI-50. Temperature log is in Figure 4.2. Red lines indicate approximate boundaries of the hot zone (i.e. where temperatures exceed 50ºC).

 

Figure 4.4: Variations in LL (liquid limit) and PI (plasticity index) with depth in drill hole SI-50. Temperature log is in Figure 4.2. Red lines indicate approximate boundaries of the hot zone (i.e. where temperatures exceed 50ºC).

 

93

Figure 4.5: Variations in Gypsum + jarosite, K-feldspar + plagioclase and total clay with depth in drill hole SI-50. Temperature log is in Figure 4.2. Red lines indicate approximate boundaries of the hot zone (i.e. where temperatures exceed 50ºC).

 

94

Figure 4.6: Variation in K-feldspar + plagioclase, gypsum + jarosite, total clay and slake index of the hot zone rock materials from Sugar Shack South rock pile.

4.6 Conclusion

The slake durability measurements of rock pile material collected from the hot

zones are similar to the measurements obtained for other materials in the Questa area

(Ayakwah et al., 2009) and indicate high strength. These measurements along with the

 

95

similarity in mineralogy and chemistry, especially considering that no new clays are

being formed by weathering of the material in the hot zones, suggests that the hot zones

have not noticeably changed in strength and durability as a result of being exposed to

weathering in the past 25-40 years.

 

96

5.0 CONCLUSIONS AND RECOMMENDATIONS

• The point load indices are medium to very high according to the point load

strength index classification (Fig. 2.9). The slake durability indices from the

Questa rock piles are high to extremely high according to the slake durability

index classification (Fig. 2.10)

• The slake durability indices from the various rock piles range from 80.9 to 99.5 %

and the point load strength indices range from 0.6 to 8.2 MPa. Samples from

Sugar Shack South are slightly lower in point load indices than the other rock

piles, (Tables 2.5, 2.6, Fig. 2.9 and appendix C).

• The point load values for rock fragments with different lithology range from 1.3

to 6.9 MPa, with all samples classified as high to very high strength. The slake

durability values for samples of andesite and rhyolite (Amalia Tuff) range from

83.7 to 99.6% with all samples classified as having high to extremely high

durability (Tables 2.5 and 2.6). There is no significant difference in slake

durability between different lithologies, (Figs. 2.12 and 2.13).

• The slake durability and point load test results indicate that, the samples from the

debris flows are slightly stronger (average slake durability index of 98.4% and

point load index of 4.0 MPa) than the rock pile samples and that the alteration

scar samples are slightly weaker (average slake durability index of 89.2% and

point load index of 2.8 MPa) than the rock pile samples, but still most of these

rocks are strong in terms of their slake durability and point load indices. The

alteration scar samples represent the more weathered material that has occurred

over thousands to millions of years (Tables 2.5 and 2.6; section 2.4).

 

97

• There are no strong correlations between point load and slake durability with

mineralogy or chemistry (Fig. 2.14).

• There are no strong correlations between friction angle and point load indices

with the Questa materials (Fig. 2.16).

• The debris flows are similar to the Questa rock piles in terms of lithology, slake

and point load indices, friction angle, particle size distribution but an exception is

the cohesion intercept values of the debris flow which are higher than those of the

rock piles. There are no systematic variations in the composition of the samples

collected from the profile, indicating that the debris flow was formed by several

different flood events with slightly different sources (Table 3.1).

• There are no clear trends within the debris flow profile to indicate an increase in

weathering with depth in the profile. The results of the geochemical

characterization indicate that, the samples collected from the debris flow are

similar to each other and do not show signs of decreasing weathering from the top

of the profile to the bottom (Table 3.4, Figs. 3.2 and 3.3).

• The clay mineralogy from X-ray diffraction (XRD) analyses indicates that the

samples from the profile contain the same clay mineral groups as the Questa rock

piles and the alteration scar samples (Fig. 3.11).

• The results of the geotechnical testing indicate there is no clear trend of

decreasing strength with increasing depth for the samples from the debris flow

profile.

 

98

• The cementation agents are similar to those found in the rock piles and are formed

by oxidation of sulfide minerals producing sulfates and iron oxides. The debris

flows are well cemented, even below the surface.

• Distribution of sulfide and sulfate minerals suggests an open-system behavior (i.e.

movement of sulfur within the debris flow).

• The slake durability measurements of rock pile material collected from the hot

zones are similar to the measurements obtained for other materials in the Questa

area and indicate high strength (Table 3.1 and 4.1).

5.2 References Cited

ASTM, 2001, American Society for Testing Materials. Procedures for testing soils, 1964. Standard Test Method for Slake Durability of Shales and Similar Weak Rocks: D464487 (Reapproved 1992): Annual Book of ASTM Standards, West Conshohocken, PA.

Bieniawski, Z.T., 1975, Point load test in geotechnical practice, Engineering Geology, 9(1), 1- 11.

Blowes, D. W., and Jambor, J.L., 1990, The pore-water geochemistry and mineralogy of the vadose zone of sulfide tailings, Waite Amulet, Quebec, Canasa: Applied Geochemistry. v. 5, pp. 327-346.

Boakye, K., 2008, “Large in situ direct shear tests on rock piles at the Questa Mine, Taos County, New Mexico”: M.S. thesis, New Mexico Institute of Mining and Technology, Socorro, 156 p.

Broch, E. and Franklin, J. A., 1972, The Point Load Strength Test: International Journal of Rock Mechanics and Mineral Sciences, v. 9, p. 669-697.

Caine, J. S., 2003, Questa baseline and pre-mining ground-water quality investigation 6: Preliminary brittle structural geologic data, Questa mining district, southern Sangre de Cristo Mountains, New Mexico: U.S. Geological Survey, Open-file Report 02-0280.

Carpenter, R. H., 1968, Geology and Ore Deposits of the Questa Molybdenum Mine Area, Taos County, New Mexico., Ore Deposits of the United States, 1933-1967, AIME Graton-Sales, American Institute of Mining, Metallurgical and Petroleum Engineers, p. 1328-1350.

Cetin, H., Laman, M. and Ertunc, 2000, Settlement and slaking problems in the world’s fourth largest rock-fill dam, the Ataturk Dam in Turkey, Engineering Geology 56(3-4), 225-242.

 

99

D’Andrea, D.V., Fisher, R.L. and Fogelson, D.E., 1964, Prediction of compression strength from other rock properties, Colorado School of Mines Quarterly, 59(4B), 623-640.

Dhakal, G., Yoneda, T., Kato, M., and Kaneko, K., 2002, Slake Durability and Mineralogical Properties of some Pyroclastic and Sedimentary Rocks: Engineering Geology, v. 65, p. 31-45.

Dhakal, G. P, Kodama, J., Kato, M., Yoneda, T., Neaupane, K.M., and Goto, T., 2004, Durability characteristics of some assorted rocks: Engineering Geology, v. 65, p. 31-45.

Dick, J.C. and Shakoor, A. 1995, Characterizing durability of mud rocks for slope stability purposes: Geological Society America, Reviews in Engineering Geology, v. X, p. 121-130.

Donahue K. M. , Dubar, N. W. , Heizler, L. L., and McLemore, V. T. 2008, Origins of clay minerals in the Goathill North Rock Pile, Questa Mine, Taos County, New Mexico, unpublished report to Chevron Mining Inc.

Duzgoren-Aydin, N.S., Aydin, A., and Malpas, A.J., 2002, Re-assessment of chemical weathering indices: case study on pyroclastic rocks of Hong Kong: Engineering Geology, v. 63, p. 99-119.

Fookes, P. G., Dearman, W. R., and Franklin, J. A., 1971, Some engineering aspects of rock weathering with field examples from Dartmoor and elsewhere: Quarterly Journal of Engineering Geology, v. 4, p. 139-185.

Fookes, P.G., Gourley, C.S., and Ohikere, C., 1988, Rock weathering in engineering time: Quarterly Journal of Engineering Geology, v. 21, p. 33-57.

Franklin, J.A., and Chandra, A., 1972, The slake durability test: International Journal of Rock Mechanics and Mineral Sciences: v. 9, p. 325–341.

Geological Society Engineering Working Party Report, 1995, The description and classification of weathered rocks for engineering: Quarterly Journal of Engineering Geology, v. 28, p. 207-242.

Gupta, A.S. and Rao, K. S., 2001, Weathering indices and their applicability for crystalline rocks: Bull. Eng. Geol. Env., v. 60, p. 201-221.

Gupta, V. and Ahmed I., 2007, The effect of pH of water and mineralogical properties on the slake durability (degradability) of different rocks from the Lesser Himalaya, India: Engineering Geology 95, 79-87.

Gunsallus, K.L. and Kulhawy, F.H., 1984, Comparative evaluation of rock strength measures, International Journal Rock Mechanic Mining Science Geomechanic Abstract, 2(5), 233-248.

Gutierrez, L. A. F., 2006. The Influence of Mineralogy, Chemistry and Physical Engineering properties on Shear Strength Parameters of the Goathill North Rock Pile Material, Questa Molybdenum Mine, New Mexico: M. S. thesis, New Mexico Institute of Mining and Technology, Socorro, 201. pp.,http://geoinfo.nmt.edu/staff/mclemore/Molycorppapers.htm,. Accessed October 10 2008.

Gutierrez, L.A.F., Viterbo, V.C., McLemore, V.T., and Aimone-Martin, C.T., 2008, Geotechnical and Geomechanical Characterisation of the Goathill North Rock Pile at the Questa Molybdenum Mine, New Mexico, USA; in Fourie, A., ed., First

 

100

International Seminar on the Management of Rock Dumps, Stockpiles and Heap Leach Pads: The Australian Centre for Geomechanics, University of Western Australia, p. 19-32.

Gökçeoğlu, C., Ulusay, R. and Sönmez, H., 2000, Factors affecting the durability of selected weak and claybearing rocks from Turkey, with particular emphasis in the influence of the number of drying and wetting cycles: Engineering Geology, v. 57, p. 215-237.

Graf, G., 2008, Mineralogical and geochemical changes associated with sulfide and silicate weathering in natural alteration scars, Taos County, New Mexico: M.S. thesis, New Mexico Institute of Mining and Technology, Socorro, 193 p., http://geoinfo.nmt.edu/staff/mclemore/Molycorppapers.htm, accessed April 28, 2008.

Hall, J.S., 2004, New Mexico Bureau of Mines and Mineral Resource’s Clay Laboratory Manual: Unpublished New Mexico Bureau of Geology and Mineral Resources report.

Hassani, F.P., Scoble, M.J and Whittaker, B.N., 1980, Application of point load index test to strength determination of rock and proposals for new size correction chart, Proc. 21st Symposium Rock Mechanics Rolla, pp. 543-564.

International Society for Rock Mechanics (ISRM), 1979, Suggested Methods for determination of the slake durability index: International Journal of Rock Mechanics and Mineral Sciences Geomech., v. 16, 154-156.

International Society for Rock Mechanics (ISRM), 1985, Suggested Methods for determining point load strength: International Journal of Rock Mechanics and Mineral Sciences Geomech., p. 53-60.

Jerz, J.K., 2002, Geochemical Reactions in Unsaturated Mine Wastes: PhD dissertation, University of Virginia, Blacksburg, 115 p.

Jerz, J.K. and Rimstidt, J.D., 2004, Pyrite oxidation in humid air: Geochimica Cosmochimica Acta, vol. 68, p. 701-714.

Johnson, R.B., DeGraff, J.V., 1988, Principles of Engineering Geology, Wiley, New York, pp 497.

Kolay, E. and Kayabali, K., 2006, Investigating of the effect of aggregate shape and surface roughness on the slake durability index using the fractal dimension approach: Engineering Geology 86, 271-284.

Lefebvre, R., Lamontagne, A., Wels, C., and Robertson, A., 2002, ARD Production and Water Vapor Transport at the Questa Mine, Tailings and Mine Waste '02:

Proceedings of the Tailings & Mine Waste '02 Conference, January 27-30: Fort Collins, A.A.Balkema, p. 479-488.

Lipman, P. W., 1981, Volcano-tectonic setting of tertiary ore deposits, southern Rocky Mountains: Arizona Geological Society Digest, v. 14, p. 199-213.

Little, A.L., 1969, The engineering weathering classification of residual tropical soils; in Proceedings of the 7th International Conference on Soil Mechanics and Foundation Engineering, Special Session on the Engineering Properties of Lateritic Soils: Mexico City, p. 1-10.

 

101

Ludington, S., Plumlee, G. S., Jonathan, C., Bove, D., Holloway, J., and Livo, E., 2004, Questa baseline and pre-mining ground-water quality investigation. 10. Geologic influences on ground and surface waters in the lower Red River watershed, New Mexico: United States Geological Survey, Scientific Investigations Report 2004-5245.

Lueth, V. W., Samuels, K. E., and Campbell, A. R. (2008) Final report on the geochronology (40Ar/39Ar) dating of Red River Alteration scars and debris flows, unpublished report to Chevron Mining Inc.

Maharana Pratap University of Agriculture and Technology, 2005, Designing of waste dumps vis a vis land use planning for marble quarries in southern Rajasthan, India: 20th World Mining Congress.

Meyer, J. and Leonardson, R., 1990, Tectonic, hydrothermal, and geomorphic controls on alteration scar formation near Questa, New Mexico: New Mexico Geological Society, Guidebook 41, p. 417-422.

Meyer, J. W., and Leonardson, R. W., 1997, Geology of the Questa mining district: Volcanic, plutonic, tectonic and hydrothermal history, New Mexico Bureau of Mines and Mineral Resources Bulletin, Open File Report 431: Socorro, 187 p.

McLemore, V. T., Lueth, V. W., and Walker, B. M., 2004d, Alteration scars in the Red River valley, Taos County, New Mexico: New Mexico Geological Society Guidebook, v. 55, p. 19.

McLemore, V. T., Walsh, P., Donahue, K., Gutierrez, L., Tachie-Menson, S.,Shannon, H. R., and Wilson, G. W., 2005, Preliminary Status Report on Molycorp Goathill North Trenches, Questa, New Mexico In: 2005 National Meeting of the American Society of Mining and Reclamation. American Society of Mining and Reclamation, Breckenridge, Colorado, 26 pp., http://geoinfo.nmt.edu/staff/mclemore/Molycorppapers.htm, accessed June 19, 2008.

McLemore, V.T., Donahue, K.M., Phillips, E., Dunbar, N., Walsh, P., Gutierrez, L.A.F., Tachie-Menson, S., Shannon, H.R., Wilson, G.W., and Walker, B.M., 2006a, Characterization of Goathill North Mine Rock Pile, Questa Molybdenum Mine, Questa, New Mexico: National Meeting of the 7th ICARD, SME, and American Society of Mining and Reclamation, St. Louis, Mo., March, CD-ROM, http://geoinfo.nmt.edu/staff/mclemore/Molycorppapers.htm

McLemore, V.T., Donahue, K., Phillips, E., Dunbar, N., Smith, M., Tachie-Menson, S., Viterbo, V., Lueth, V.W., Campbell, A.R. and Walker, B.M., 2006b, Petrographic, mineralogical and chemical characterization of Goathill North Mine Rock Pile, Questa Molybdenum Mine, Questa, New Mexico: 2006 Billings Land Reclamation Symposium, June, 2006, Billings, Mt. Published by Published by American Society of Mining and Reclamation, 3134 Montavesta Rd., Lexington, KY CD-ROM, http://geoinfo.nmt.edu/staff/mclemore/Molycorppapers.htm

McLemore, V.T., Ayakwah, G., Boakye, K., Campbell, A., Donahue, K., Dunbar, N., Gutierrez, L. Heizler, L., Lynn, R., Lueth, V., Osantowski, E., Phillips, E., Shannon, H., Smith, M. Tachie-Menson, S., van Dam, R., Viterbo, V.C., Walsh, P., and Wilson, G.W., 2008a, Characterization of Goathill North Rock Pile:

 

102

revised unpublished report to Molycorp, Tasks: 1.3.3, 1.3.4, 1.4.2, 1.4.3, 1.11.1.3, 1.11.1.4, 1.11.2.3, B1.1.1, B1.3.2.

McLemore, V.T., Donahue, K., and Sweeney, D., 2008b, Lithologic atlas for the Questa mine, Taos County, New Mexico: revised unpublished report to Molycorp, February 11, 2004, Revised August 27, 2008 (revised from appendix 2.3, May 2005 report).

McLemore, V.T., Sweeney, D., Dunbar, N., Heizler, L. and Phillips, E., 2009, Determining bulk mineralogy using a combination of petrographic techniques, whole rock chemistry, and MODAN: Society of Mining, Metallurgy and Exploration Annual Convention, preprint Feb 2009.

Molycorp Inc., 2002, Request for Letters of Intent, : Questa, NM. http://www.infomine.com/consultants/doc/mcrliaun.pdf. Accessed, April 20th, 2008

Molycorp Inc., 2007, History, Mineralogy and Mining - Questa, NM. http://www.molycorp.com/operational_excellence/qhistory.asp. Accessed; May 2nd, 2008.

Molling, P. A., 1989, Applications of the reaction progress variable to hydrothermal alteration associated with the deposition of the Questa molybdenite deposit: Ph. D. dissertation, Johns Hopkins University, Baltimore, MD, 227 p.

Moore, O.M. and Reynolds, R.O., Jr., 1989, X-ray diffraction and the identification and analyses of clay minerals: Oxford University Press, New York. 378 p.

Morin, K.A., Gerencher, E., Jones, C. E., and Konasewich, D. E., 1991, Critical literature review of acid rock drainage from waste rock: MEND 1.11.1, 176 p.

Morth, A. H. and Smith, E. E., 1966, Kinetics of the sulfide-to-sulfate reaction: Am. Chem. Soc. Div. Fuel Chem. Preprints 10, 83.

Neuendorf, K.K.E., Mehl, Jr., J.P., and Jackson, J.A., 2005, Glossary of geology, 5th ed.: American Geological Institute, Alexandria, Virginia, 779 p.

Norwest Corporation, 2003. Goathill North Mine Rock Pile Evaluation and Conceptual Mitigation Plan. Unpublished Report to Molycorp Inc.

Nunoo S., McLemore, V.T., Fakhimi, A., Ayakwah, G., 2009, The effect of weathering on particle shape of Questa mine material: Society of Mining, Metallurgy and Exploration Annual Convention, preprint Feb 2009.

Nunoo S., 2009, Geotechnical Evalution of Questa mine materials, Taos County, New Mexico: M.S. thesis, New Mexico Institute of Mining and Technology, Socorro.

Paktunc, A.D., 1998, MODAN: An interactive computer program for estimating mineral quantities based on bulk composition: Computers and Geoscience, v. 24 (5), p. 425-431.

Paktunc, A.D., 2001, MODAN—A Computer program for estimating mineral quantities based on bulk composition: Windows version. Computers and Geosciences, 27, 883-886.

Panek, L. A. and Fannon, T.A., 1992, Size and shape effects in point load tests of irregular rock fragments, Rock Mechanics Rock Engineering, 25, 109-40.

Piché, M. and Jébrak, M., 2004, Normative minerals and alteration indices developed for mineral exploration: Journal of Geochemical Exploration, v. 82, p. 59-77.

 

103

Plumlee, G.S., Ludington, S., Vincent, K.R., Verplanck, P.L., Caine, J.S., and Livo, K.E., 2006, Questa Baseline and Pre-Mining Ground-Water Quality Investigation. 7. A pictorial record of chemical weathering, erosional processes and potential debri-flow hazards in scar areas developed on hydrothermally altered rocks. U.S. Geological Survey Open-File Report 2006-1205.

Quine, R. L., 1993, Stability and deformation of mine waste dumps in north central Nevada: PhD. dissertation, University of Nevada, Reno, 402 p.

Rehrig, W. A., 1969, Fracturing and its effects on molybdenum mineralization at Questa, New Mexico: Ph. D. dissertation, University Arizona, Tucson, AZ, 175 p.

Ritchie, A.I.M., 2003, Oxidation and gas transport in piles of sulfidic waste; in Environmental aspects of mine wastes: Mineralogical Association of Canada, Short Course Series, v. 21, p. 73-94.

Robertson GeoConsultants, Inc., 2000, Progress Report: Questa Mine Rock Pile Monitoring and Characterization Study, Open-file Report No. 052007/3 for Molycorp Inc.

Rodrigues, J.G., 1991, Physical characterization and assessment of rock durability through index properties. NATO ASI Ser. Ed. Applied Sciences 200, 7-34.

Schilling J.H., 1956, Geology of the Questa molybdenum (Moly) mine area, Taos County, New Mexico, State Bureau of Mines and Mineral Resources, New Mexico Institute of Mining and Technology, Campus Station, New Mexico, Bulletin 51:87.

Shannon, H., Sigda, J., van Dam, R., Hendrickx, J., and McLemore, V.T., 2005, Thermal Camera Imaging of Rock Piles at the Questa Molybdenum Mine, Questa, New Mexico: National Meeting of the American Society of Mining and Reclamation, Breckenridge, Colo, June, CD-ROM.

Shaw, S., Wels, C., Robertson, A., Fortin, S., and Walker, B., 2003, Background characterization study of naturally occurring acid rock drainage in the Sangre de Cristo Mountains, Taos County, New Mexico; in ICARD 2003—Proceedings from the 5th international conference on acid rock drainage: The Australasian Institute of Mining and Metallurgy, Melbourne, p. 605-616.

Shum, M. G. W., 1999, Characterization and dissolution of secondary weathering products from the Gibraltar mine site: M. S. thesis, University of British Columbia, Vancouver, 310 p.

Smith, K.S., Briggs, P.H., Campbell, D.L., Castle, C.J., Desborough, G.A., Eppinger, R.G., III, Fitterman, D.V., Hageman, P.L., Leinz, R.W., Meeker, G.P., Stanton, M.R., Sutley, S.J., Swayze, G.A., and Yager, D.B., 2000a, Tools for the rapid screening and characterization of historical metalmining waste dumps, in Proceedings of the 2000 Billings Land Reclamation Symposium, Billings, Montana, March 2024, 2000: Bozeman, Montana State University, Reclamation Research Unit Publication No. 0001 (CDROM), p. 435442, http://crustal.usgs.gov/minewaste/pdfs/ksmith_billings.pdf.

 

104

Smith, L. and Beckie, R., 2003, *Hydrologic and geochemical transport processes in mine waste rock;** */in/ Environmental aspects of *mine** **wastes: *Short Course Series, v. 31, p. 51-72.

Tachie-Menson, S., 2006, Characterization of the acid producing potential and investigation of its effect on weathering of the Goathill North rock pile at the Questa Molybedenum Mine, New Mexico: M.S. thesis, New Mexico Institute of Mining and Technology, Socorro, NM, 209 pp., http://gepinfo.nmt.edu/staff/mclemore/Molycorppapers.htm. Accessed January 19, 2008.

Tamotsu, T. 2007, Debris flow mechanics, prediction and countermeasures: Balkema-Proceedings-Engineering, p 6.

URS Corporation (2000), “Interim mine rock pile erosion and stability evaluations, Questa Mine”, unpublished report to Molycorp, Inc., 6800044388.00, December 1, at http://www.molycorp.com/home_frameset.html, accessed May 15, 2008.

URS Corporation, 2003, Interim Mine Rock Pile Erosion and Stability Evaluations, Questa Mine. Unpublished Report to Molycorp Inc.

Viterbo, V., 2007, Effect of premining hydrothermal alteration processes and postmining weathering on rock engineering properties of Goathill north rock pile at the Questa Mine, Toas , New Mexico: M. S. thesis, New Mexico Institute of Mining and Technology, Socorro, NM, 209 p., http://geoinfo.nmt.edu/staff/mclemore/Molycorppapers.htm, accessed March 10, 2008.

Viterbo, V., McLemore, V.T., Donahue, K., Aimone-Martin, C., Fakhimi, A., and Sweeney, D. 2007, Effects of chemistry, mineralogy, petrography and alteration on rock engineering properties of the Goathill North rock pile at the Molycorp Questa Mine, New Mexico: SME Annual Meeting, Preprint 07-099, Denver, Colorado.

Wels, C., Loudon, S., and Fortin, S., 2002, Factors Influencing Net Infiltration into Mine Rock Piles at Questa Mine, New Mexico, Tailings and Mine Waste '02: Proceedings of the Tailings & Mine Waste '02 Conference, January 27-30: Fort Collins, CO., A. A. Balkema, p. 469-478. http://minerals.usgs.gov/minerals/pubs/commodity/molybdenum/ assessed July 30th, 2008

Wels, C., Lefebvre, R., and Robertson, A.M., 2003, An overview of prediction and control of air flow in gas acid-generating waste rock dumps; in ICARD 2003—Proceedings from the 5th international conference on acid rock drainage: The Australasian Institute of Mining and Metallurgy, Melbourne, p. 639-650.

Zhao, J., Broms, B.B., Zhou, Y. and Choa, V., 1994, A study of the weathering of the Bukit Timah Granite, Part A: Review, Field Observations and Geophysical Survey, Bulletin of the International Association of Engineering Geology, Paris vol. 49 (1994).

 

105

APPENDIX A TEST RESULTS

Appendix A1: Point Load Test Results

Table A1: Point Load Strength Summary Results excluding the work by Viterbo, (2007).

SAMPLE ID Point Load Strength Index

Is(50) (MPa)

Standard Deviation (MPa) Coefficient of Variation % Strength Classification

MID-AAF-0001 4.36 0.48 11 Very High MID-VTM-0002 4.53 0.27 6 Very High MIN-AAF-0010 3.52 0.63 18 Very High MIN-AAF-0012 3.50 0.61 17 Very High MIN-AAF-0013 4.01 1.22 30 Very High MIN-AAF-0015 3.25 0.28 9 Very High MIN-GFA-0001 2.75 0.72 26 High MIN-GFA-0003 5.95 1.08 18 Very High MIN-GFA-0005 2.61 0.28 11 High MIN-GFA-0009 3.80 1.19 31 Very High MIN-SAN-0001 5.04 1.45 29 Very High MIN-VTM-0002 4.64 0.20 4 Very High MIN-VTM-0007 4.45 0.81 18 Very High MIN-VTM-0009 4.86 0.45 9 Very High QPS-AAF-0019 3.77 0.80 21 Very High QPS-AAF-0020 2.57 0.65 25 High QPS-AAF-0022 2.52 0.50 20 High QPS-SAN-0001 3.50 0.72 20 Very High QPS-VTM-0001 1.71 0.46 27 High SPR-AAF-0001 3.92 0.43 11 Very High SPR-AAF-0003 4.80 0.38 8 Very High SPR-SAN-0001 2.08 0.72 35 High SPR-VTM-0005 2.81 0.47 17 High SPR-VTM-0008 3.39 0.50 15 Very High SPR-VTM-0010 1.34 0.37 28 High SPR-VTM-0021 2.60 0.30 12 High SSS-AAF-0004 1.62 0.18 11 High SSS-AAF-0005 1.03 0.27 26 High SSS-AAF-0007 2.19 0.53 24 High SSS-AAF-0012 2.08 0.18 9 High SSS-EHP-0014 2.45 0.05 2 High SSS-EHP-0016 3.79 0.27 7 Very High SSS-VTM-0010 2.30 0.46 20 High SSS-VTM-0012 2.19 0.17 8 High SSW-AAF-0001 4.37 0.82 19 Very High SSW-AAF-0005 1.68 0.13 8 High SSW-AAF-0007 5.30 2.94 55 Very High SSW-AAF-0009 4.01 0.72 18 Very High SSW-SAN-0001 2.51 1.05 42 High SSW-SAN-0007 2.03 0.44 22 High

 

106

SSW-VTM-0016 4.40 0.48 11 Very High SSW-VTM-0019 5.02 0.12 2 Very High SSW-VTM-0022 4.57 1.06 23 Very High SSW-VTM-0023 5.20 0.53 10 Very High SSW-VTM-0028 6.06 0.55 9 Very High SSW-VTM-0030 4.19 0.35 8 Very High

Figure A1: Point Load Strength Plot of Sample SSW-SAN-0001 (a) with the entire data points whereas (b) shows a plot with the removed deviated points.

Figure A2: Point Load Strength Plot of Sample MIN-SAN-0001(a) with the entire data points whereas (b) shows a plot with the removed deviated points.

 

 

 

 

 

(a) (b)

(a) (b)

 

107

 

Figure A3: Point Load Strength Plot of Sample SPR-SAN-0001(a) with the entire data points whereas (b) shows a plot with the removed deviated points.

 

Figure A4: Point Load Strength Plot of Sample SSW-SAN-0007 (a) with the entire data points whereas (b) shows a plot with the removed deviated points.

 

Figure A5: Point Load Strength Plot of Sample MIN-GFA-0005(a) with the entire data points whereas (b) shows a plot with the removed deviated points.

(b) (a)

(a) (b)

(a) (b)

 

108

 

Figure A6: Point Load Strength Plot of Sample MIN-GFA-0009(a) with the entire data points whereas (b) shows a plot with the removed deviated points.

Figure A7: Point Load Strength Plot of Sample MIN-GFA-0003(a) with the entire data points whereas (b) shows a plot with the removed deviated points.

Figure A8: Point Load Strength Plot of Sample SSW-AAF-0005 (a) with the entire data points whereas (b) shows a plot with the removed deviated points.

(b) (a)

(a) (b)

(b) (a)

 

109

 

Figure A9: Point Load Strength Plot of Sample MIN-AAF-0015 (a) with the entire data points whereas (b) shows a plot with the removed deviated points.

 

Figure A10: Point Load Strength Plot of Sample MIN-GFA-0001(a) with the entire data points whereas (b) shows a plot with the removed deviated points.

 

Figure A11: Point Load Strength Plot of Sample MIN-AAF-0013 (a) with the entire data points whereas (b) shows a plot with the removed deviated points.

(a) (b)

(a) (b)

(a) (b)

 

110

   

Figure A12: Point Load Strength Plot of Sample QPS-SAN-0001 (a) with the entire data points whereas (b) shows a plot with the removed deviated points.

 

Figure A13: Point Load Strength Plot of Sample MIN-AAF-0012 (a) with the entire data points whereas (b) shows a plot with the removed deviated points.

Figure A14: Point Load Strength Plot of Sample MIN-AAF-0010 (a) with the entire data points whereas (b) shows a plot with the removed deviated points.

 

(b) (a)

(a) (b)

(a) (b)

 

111

 

Figure A15: Point Load Strength Plot of Sample SSW-AAF-0007 (a) with the entire data points whereas (b) shows a plot with the removed deviated points.

 

Figure A16: Point Load Strength Plot of Sample QPS-AAF-0019 (a) with the entire data points whereas (b) shows a plot with the removed deviated points.

 

Figure A17: Point Load Strength Plot of Sample QPS-AAF-0020 (a) with the entire data points whereas (b) shows a plot with the removed deviated points.

 

(a) (b)

(a) (b)

(b) (a)

 

112

   

Figure A18: Point Load Strength Plot of Sample QPS-AAF-0022 (a) with the entire data points whereas (b) shows a plot with the removed deviated points.

 

Figure A19: Point Load Strength Plot of Sample QPS-VTM-0001 (a) with the entire data points whereas (b) shows a plot with the removed deviated points.

Figure A20: Point Load Strength Plot of Sample SPR-AAF-0003 (a) with the entire data points whereas (b) shows a plot with the removed deviated points.

(a) (b)

(a) (b)

(a) (b)

 

113

   

Figure A21: Point Load Strength Plot of Sample SPR-AAF-0001 (a) with the entire data points whereas (b) shows a plot with the removed deviated points.

 

Figure A22: Point Load Strength Plot of Sample SSW-VTM-0023 (a) with the entire data points whereas (b) shows a plot with the removed deviated points.

 

Figure A23: Point Load Strength Plot of Sample SSW-VTM-0019 (a) with the entire data points whereas (b) shows a plot with the removed deviated points.

(a) (b)

(b) (a)

(a) (b)

 

114

 

   

Figure A24: Point Load Strength Plot of Sample SSW-AAF-0005 (a) with the entire data points whereas (b) shows a plot with the removed deviated points.

 

Figure A25: Point Load Strength Plot of Sample SPR-VTM-0021 (a) with the entire data points whereas (b) shows a plot with the removed deviated points.

   

Figure A26: Point Load Strength Plot of Sample MIN-VTM-0002 (a) with the entire data points whereas (b) shows a plot with the removed deviated points.

(a) (b)

(b) (a)

(a) (b)

 

115

 

  

 

 

Figure A27: Point Load Strength Plot of Sample SSS-AAF-0012 (a) with the entire data points whereas (b) shows a plot with the removed deviated points.

 

Figure A28: Point Load Strength Plot of Sample SSW-AAF-0009 (a) with the entire data points whereas (b) shows a plot with the removed deviated points.

 

Figure A29: Point Load Strength Plot of Sample SSS-AAF-0004 (a) with the entire data points whereas (b) shows a plot with the removed deviated points.

 

(a) (b)

(a)

(a)

(b)

(b)

 

116

 

Figure A30: Point Load Strength Plot of Sample MIN-VTM-0007 (a) with the entire data points whereas (b) shows a plot with the removed deviated points.

Figure A31: Point Load Strength Plot of Sample MIN-VTM-0009 (a) with the entire data points whereas (b) shows a plot with the removed deviated points.

Figure A32: Point Load Strength Plot of Sample SSS-EHP-0014 (a) with the entire data points whereas (b) shows a plot with the removed deviated points.

 

(a) (b)

(a) (b)

(a) (b)

 

117

 

Figure A33: Point Load Strength Plot of Sample SSS-VTM-0012 (a) with the entire data points whereas (b) shows a plot with the removed deviated points.

   

Figure A34: Point Load Strength Plot of Sample SSS-EHP-0016 (a) with the entire data points whereas (b) shows a plot with the removed deviated points.

   

Figure A35: Point Load Strength Plot of Sample SSS-VTM-0010 (a) with the entire data points whereas (b) shows a plot with the removed deviated points.

(a) (b)

(b) (a)

(a) (b)

 

118

 

Figure A36: Point Load Strength Plot of Sample SSS-AAF-0005 (a) with the entire data points whereas (b) shows a plot with the removed deviated points.

   

Figure A37: Point Load Strength Plot of Sample SPR-VTM-0010 (a) with the entire data points whereas (b) shows a plot with the removed deviated points.

 

Figure A38: Point Load Strength Plot of Sample MID-AAF-0001 (a) with the entire data points whereas (b) shows a plot with the removed deviated points.

 

(a) (b)

(a) (b)

(b) (a)

 

119

   

Figure A39: Point Load Strength Plot of Sample SSS-AAF-0007 (a) with the entire data points whereas (b) shows a plot with the removed deviated points.

   

Figure A40: Point Load Strength Plot of Sample SSW-AAF-0001(a) with the entire data points whereas (b) shows a plot with the removed deviated points.

Figure A41: Point Load Strength Plot of Sample SSW-VTM-0030 (a) with the entire data points whereas (b) shows a plot with the removed deviated points.

 

(a) (b)

(a) (b)

(b) (a)

 

120

 

Figure A42: Point Load Strength Plot of Sample SPR-VTM-0005 (a) with the entire data points whereas (b) shows a plot with the removed deviated points.

 

Figure A43: Point Load Strength Plot of Sample SPR-VTM-0008 (a) with the entire data points whereas (b) shows a plot with the removed deviated points.

   

Figure A44: Point Load Strength Plot of Sample SSW-VTM-0028 (a) with the entire data points whereas (b) shows a plot with the removed deviated points.

(a) (b)

(a) (b)

(a) (b)

 

121

   

Figure A45: Point Load Strength Plot of Sample MID-VTM-0002 (a) with the entire data points whereas (b) shows a plot with the removed deviated points.

    

Figure A46: Point Load Strength Plot of Sample SSW-VTM-0022 (a) with the entire data points whereas (b) shows a plot with the removed deviated points.

   

 

Figure A47: Point Load Strength Plot of Sample SSW-VTM-0016 (a) with the entire data points whereas (b) shows a plot with the removed deviated points.

(a) (b)

(a) (b)

(a) (b)

 

122

Appendix A2: Slake Durability Test Results.

Table A2: Slake Durability Index Summary Results excluding the work by Viterbo, (2007).

Sample ID ID2 (%) Durability Classification Type Water

Content (%)

HAN-GJG-0007 90.20 Very High II 3.79 HAN-GJG-0009 94.01 Very High II 1.94 HAN-GJG-0010 87.02 High II 1.75 HAS-GJG-0004 70.84 Medium III 8.47 HAS-GJG-0008 92.42 Very High II 9.73 HAS-GJG-0014 81.24 High II 2.83 MID-AAF-0001 95.61 Extremely High II 0.79 MID-AAF-0002 97.34 Extremely High II 0.86 MID-VTM-0002 97.64 Extremely High II 1.80 MIN-AAF-0001 97.61 Extremely High II 0.95 MIN-AAF-0004 96.12 Extremely High II 1.03 MIN-AAF-0006 95.98 Extremely High II 0.42 MIN-AAF-0010 97.32 Extremely High I 1.61 MIN-AAF-0013 98.23 Extremely High II 1.8 MIN-AAF-0015 99.09 Extremely High II 1.66 MIN-GFA-0001 98.42 Extremely High I 1.95 MIN-GFA-0003 99.46 Extremely High I 2.32 MIN-GFA-0005 98.71 Extremely High I 2.19 MIN-GFA-0009 98.57 Extremely High I 2.25 MIN-SAN-0001 98.61 Extremely High I 2.13 MIN-VTM-0002 98.65 Extremely High II 0.57 MIN-VTM-0003 99.23 Extremely High I 0.76 MIN-VTM-0004 98.88 Extremely High II 0.85 MIN-VTM-0006 98.85 Extremely High I 1.07 MIN-VTM-0007 98.87 Extremely High I 0.90 MIN-VTM-0008 98.81 Extremely High I 1.00 MIN-VTM-0009 98.58 Extremely High I 2.13 QPS-AAF-0001 97.10 Extremely High I 1.08 QPS-AAF-0003 90.08 Very High II 2.95 QPS-AAF-0005 96.99 Extremely High II 1.29 QPS-AAF-0009 94.94 Very High II 1.91 QPS-AAF-0019 97.99 Extremely High I 2.02 QPS-AAF-0020 94.69 Very High II 3.32

 

123

QPS-AAF-0022 94.41 Very High II 3.20 QPS-SAN-0001 92.39 Very High II 0.53 QPS-VTM-0001 95.23 Extremely High II 3.60 SPR-AAF-0001 97.21 Extremely High I 0.52 SPR-AAF-0003 97.84 Extremely High II 0.99 SPR-SAN-0001 97.96 Extremely High II 1.05 SPR-AAF-0003 83.51 High II 1.80 SPR-VTM-0005 98.64 Extremely High II 0.42 SPR-VTM-0008 98.49 Extremely High II 0.81 SPR-VTM-0010 97.82 Extremely High II 0.71 SPR-VTM-0012 96.89 Extremely High II 0.45 SPR-VTM-0014 98.21 Extremely High II 0.89 SPR-VTM-0017 67.67 Medium III 1.25 SPR-VTM-0019 98.05 Extremely High II 0.83 SPR-VTM-0021 96.84 Extremely High II 1.04 SSS-AAF-0004 96.94 Extremely High II 2.72 SSS-AAF-0005 96.49 Extremely High II 2.91 SSS-AAF-0007 90.95 Very High III 2.38 SSS-AAF-0009 94.79 Very High II 3.12 SSS-AAF-0011 85.33 High II 1.11 SSS-AAF-0012 97.21 Extremely High II 0.86 SSS-EHP-0001 98.34 Extremely High II 0.50 SSS-EHP-0002 98.45 Extremely High I 1.20 SSS-EHP-0003 98.87 Extremely High I 0.72 SSS-EHP-0006 98.38 Extremely High I 1.07 SSS-EHP-0011 98.66 Extremely High II 0.71 SSS-EHP-0012 98.27 Extremely High I 0.90 SSS-EHP-0014 99.13 Extremely High I 0.66 SSS-EHP-0015 99.28 Extremely High I 0.72 SSS-EHP-0017 99.16 Extremely High I 0.71 SSS-EHP-0019 99.18 Extremely High I 0.35 SSS-EHP-0020 97.28 Extremely High II 0.72 SSS-EHP-0021 96.16 Extremely High I 0.77 SSS-EHP-0025 98.95 Extremely High II 0.53 SSS-EHP-0029 99.32 Extremely High I 0.57 SSS-EHP-0030 99.54 Extremely High I 0.58 SSS-EHP-0031 99.28 Extremely High II 0.98 SSS-EHP-0032 99.52 Extremely High I 0.49 SSS-EHP-0033 99.35 Extremely High I 0.86

 

124

SSS-EHP-0034 99.50 Extremely High I 0.73 SSS-EHP-0036 99.13 Extremely High II 0.84 SSS-VTM-0010 97.60 Extremely High II 1.83 SSS-VTM-0012 96.80 Extremely High II 3.93 SSS-VTM-0600 96.80 Extremely High II 0.96 SSW-AAF-0001 97.49 Extremely High II 2.47 SSW-AAF-0002 96.65 Extremely High II 1.07 SSW-AAF-0005 82.30 High II 1.09 SSW-AAF-0007 95.21 Extremely High II 0.93 SSW-SAN-0001 96.07 Extremely High I 1.09 SSW-SAN-0007 95.18 Extremely High II 2.47 SSW-VM-0016 97.48 Extremely High II 1.88 SSW-VTM-0001 98.61 Extremely High II 0.86 SSW-VTM-0004 81.43 High II 0.29 SSW-VTM-0012 93.60 Very High II 0.58 SSW-VTM-0016 97.53 Extremely High II 1.86 SSW-VTM-0022 98.61 Extremely High II 1.36 SSW-VTM-0023 98.44 Extremely High II 1.51 SSW-VTM-0026 97.86 Extremely High II 1.75 SSW-VTM-0028 97.15 Extremely High II 0.63 SSW-VTM-0030 96.63 Extremely High II 0.59 SWH-GJG-0008 76.12 High III 7.10 SWH-GJG-0009 64.52 Medium III 5.45 SWH-GJG-0012 92.36 Very High II 5.15 SWH-GJG-0015 96.16 Extremely High II 1.80

 

125

APPENIDX B. SUMMARY RESULTS OF QUESTA MATERIALS USED IN THE STUDY. Table B1: Slake durability index, point load index, friction angle (degrees), ultimate (residual) friction angle (degrees), paste pH, and SWI for samples tested for slake durability and point load. These data include tests conducted by Viterbo, (2007).

Sample Slake Durability Index %

Point Load Index (MPa)

Peak Friction Angle (degrees)

Ultimate Friction Angle (degrees)

Paste pH SWI

Samples from trenches, test pits in GHN (rock pile material and colluvium)

GHN-EHP-0001 97.42 41.4 38.6 2.68 4

GHN-EHP-0002 97.22 42.3 35.6 3.18 3

GHN-EHP-0003 95.24 3.04 3

GHN-EHP-0004 94.76 3.02 3

GHN-EHP-0007 96.68 5.43 2

GHN-HRS-0096 96.64 43.7 38.2 3.29 3

GHN-JRM-0001 93.99 3.3 44.9 33.7 2.14 2

GHN-JRM-0031 97.27 4.46 4

GHN-JRM-0037 96.67 40.8 34.2 2.91 4

GHN-JRM-0038 96.4 42.7 39.9 2.99 2

GHN-JRM-0039 96.79 41.8 41.4 3.06 2

GHN-JRM-0040 93.23 40.8 38.5 3.37 4

GHN-JRM-0047 80.93 42.8 39.8 2.99 2

GHN-KMD-0013 96.77 2.74 40.7 39.7 2.49 2

GHN-KMD-0014 98.44 8.2 46.9 44.3 3.19 2

GHN-KMD-0015 95.71 4.3 46.9 43.7 4.92 3

GHN-KMD-0016 95.64 3.38 43.2 39.3 5.74 3

GHN-KMD-0017 89.29 0.61 43.2 39.3 2.19 3

GHN-KMD-0018 95.17 6.7 42.7 37.6 3.5 3

GHN-KMD-0019 97.61 2.96 47.3 42.2 5.84 3

GHN-KMD-0026 96.59 3.7 42.7 42 3.8 3

GHN-KMD-0027 97.02 1.1 43.5 39.7 2.49 2

GHN-KMD-0028 93.99 2.6 2

GHN-KMD-0048 98.28 5.25 6.18 2

GHN-KMD-0050 96.69 5.71 4

GHN-KMD-0051 96.58 39.9 37.2 7.19 3

GHN-KMD-0052 98.13 4.3 40.5 37.9 5.08 2

GHN-KMD-0053 94.03 3.3 41.9 40 4.32 2

GHN-KMD-0054 97.23 5.72 44.5 38.4 3.93 3

GHN-KMD-0055 94.97 1.56 44.2 39 4.27 3

GHN-KMD-0056 97.41 6.09 49 41.2 4.85 2

GHN-KMD-0057 97.65 3.19 43.1 42.4 7.96 2

GHN-KMD-0062 96.7 2.13 41.7 38.7 4.43 2

GHN-KMD-0063 98.54 7.04 44.7 40.1 3.95 2

GHN-KMD-0064 97.06 6.03 2.67 3

 

126

Sample Slake Durability Index %

Point Load Index (MPa)

Peak Friction Angle (degrees)

Ultimate Friction Angle (degrees)

Paste pH SWI

GHN-KMD-0065 95.86 4.36 43.6 41.6 5.77 4

GHN-KMD-0071 96.74 41.1 35.9 4.35 4

GHN-KMD-0072 97.68 40.5 37.5 7.15 2

GHN-KMD-0073 95.93 43.5 39.5 6.55 2

GHN-KMD-0074 98.5 41.9 42.4 3.36 3

GHN-KMD-0077 92.84 42.8 38.4 2.45 4

GHN-KMD-0078 97.58 3.58 46.2 38.7 3.26 3

GHN-KMD-0079 98 41.4 36.9 3.07 2

GHN-KMD-0080 98.4 3.45 6.36 2

GHN-KMD-0081 97.32 7.29 43.4 40.7 3.29 2

GHN-KMD-0082 96.89 5.41 42.5 39.2 3.3 2

GHN-KMD-0088 96.21 43.7 36.8 2.63 2

GHN-KMD-0090 95.66 2.44 2

GHN-KMD-0092 97.39 42.9 41.4 3.72 3

GHN-KMD-0095 97.85 47.5 43.2 2.73 2

GHN-KMD-0096 97.42 41.7 31.8 2.56 2

GHN-KMD-0097 93.64 47.8 39.7 2.55 2

GHN-KMD-0100 97.19 44.4 40.3 3.42 2

GHN-LFG-0018 96.03 4.19 2

GHN-LFG-0020 97.97 4.45 2

GHN-LFG-0037 96.49 37.8 37.8 4.5 2

GHN-LFG-0041 97.87 5.37 4

GHN-LFG-0057 98.22 2.74 4

GHN-LFG-0060 96.78 3.03 2

GHN-LFG-0085 94.42 39.6 37.5 2.98 4

GHN-LFG-0086 93.98 3.02 3

GHN-LFG-0088 98.11 40.6 38.3 5.43 4

GHN-LFG-0089 97.69 6.49 3.51 4

GHN-LFG-0090 96.72 43.8 35 6.71 4

GHN-LFG-0091 95.6 37.2 36.8 2.46 5

GHN-RDL-0002 95.72 42.2 32.1 5.48 2

GHN-RDL-0003 95.32 3.75 3

GHN-SAW-0002 99.15 2.83 2

GHN-SAW-0003 99.15 45.1 44.2 3.2 5

GHN-SAW-0004 97.13 40.1 39 2.38 2

GHN-SAW-0005 98.32 44.6 36.7 4.06 3

GHN-SAW-0200 93.62 37.6 37.5 7.54 5

GHN-SAW-0201 96.81 43.4 37.6 2.74 5

GHN-VTM-0263 85.15 40.3 37.7 2.7 3

GHN-VTM-0293 82.23 41.6 34.6 4.07 3

GHN-VTM-0450 97.98 44.5 44.5 6.7 3

GHN-VTM-0453 93.93 45.2 37.6 4.55 3

 

127

Sample Slake Durability Index %

Point Load Index (MPa)

Peak Friction Angle (degrees)

Ultimate Friction Angle (degrees)

Paste pH SWI

GHN-VTM-0456 95.66 3.19 4

GHN-VTM-0508 92.98 43.4 38.6 3.45 4

GHN-VTM-0554 85.54 7.06 3

GHN-VTM-0598 98.5 2.7 3

GHN-VTM-0599 97.07 39.3 35.4 6.96 4

GHN-VTM-0603 95.89 42.1 42.6 3.42 4

GHN-VTM-0606 96.66 43 37.2 3.25 2

GHN-VTM-0607 97.2 43.7 41.7 2.66 2

GHN-VTM-0614 98.47 42.1 39.1 3.09 5

Goat Hill alteration scar

GHR-VWL-0004 86.88 41.2 36.1 2.41 3

Hansen alteration scar

HAS-GJG-0006 70.84 33.4 32.1 2.52 2

HAS-GJG-0007 90.2 45.5 34.2 2.98 4

HAS-GJG-0008 92.42 43 2.8 5

HAS-GJG-0009 94.01 2.05 4

HAS-GJG-0010 87.02 2.6 4

HAS-GJG-0014 81.24 2.41 4

Middle rock pile

MID-AAF-0001 95.61 4.36 42.5 38.1 2.41 4

MID-AAF-0002 97.33 38 37.9 2.62 3

MID-VTM-0002 97.64 4.53 44.5 36.7 4.16 4

Goat Hill debris flow

MIN-AAF-0001 96.78 45.1 35.2 2.04 4

MIN-AAF-0004 96.1 40.6 37.9 4.23 2

MIN-AAF-0006 95.98 4.21 3

MIN-AAF-0010 97.32 3.52 48.3 37.9 3.45 3

MIN-AAF-0012 98.9 3.5 43.1 42.3 3.16 4

MIN-AAF-0013 98.23 4.01 3.44 4

MIN-AAF-0015 99.09 3.25 50.1 36 3.28 2

MIN-GFA-0001 98.42 2.75 50 37.8 3.2 4

MIN-GFA-0003 99.46 5.95 45.7 33.8 3.87 4

MIN-GFA-0005 98.71 2.61 39.2 34.9 3.24 3

MIN-GFA-0009 98.57 3.8 45.2 35.5 3.58 3

MIN-SAN-0002 98.61 5.04 39.7 40.1 3.53 4

MIN-VTM-0002 98.65 4.64 4

MIN-VTM-0003 99.23 3.67 4

MIN-VTM-0004 98.88 4.21 4

MIN-VTM-0006 98.85 3.64 3

MIN-VTM-0007 98.87 4.45 4.22 3

MIN-VTM-0008 98.81 5.06 3

MIN-VTM-0009 98.58 4.86 3.81 3

 

128

Sample Slake Durability Index %

Point Load Index (MPa)

Peak Friction Angle (degrees)

Ultimate Friction Angle (degrees)

Paste pH SWI

Samples from the open pit

PIT-LFG-0011 97.49 6.19 3

PIT-LFG-0013 92.33 37.8 37.5 2.55 3

PIT-RDL-0002 95.96 4.85 3

Drill core in the open pit deposit

PIT-VCV-0001 97.41 6.5 8.25 3

PIT-VCV-0002 96.44 5 7.87 3

PIT-VCV-0003 98.19 4.1 7.42 3

PIT-VCV-0004 88.9 1.8 4.32 3

PIT-VCV-0005 94.26 3 4.75 3

PIT-VCV-0006 95.78 3.1 4.65 3

PIT-VCV-0007 95.62 1.8 8.06 3

PIT-VCV-0008 95.25 2.3 7.95 2

PIT-VCV-0009 98.47 5.3 8.31 4

PIT-VCV-0010 94.46 3.6 8.59 2

PIT-VCV-0011 92.15 4.8 8.46 1

PIT-VCV-0012 97.22 2.6 7.93 1

PIT-VCV-0013 97.37 3 8.2 1

PIT-VCV-0014 83.65 1.8 7.9 1

PIT-VCV-0015 99.01 5 8.61 1

PIT-VCV-0016 97.2 3.44 8.46 1

PIT-VCV-0017 94.09 5.57 8.22 1

PIT-VCV-0018 94.25 1.41 8.18 1

PIT-VCV-0019 91.7 3.5 7.4 1

PIT-VCV-0020 95.38 4.4 7.56 1

PIT-VCV-0021 87.17 1.3 7.98 1

PIT-VCV-0022 93.91 2.8 7.6 1

PIT-VCV-0023 95.3 5 7.52 1

PIT-VCV-0024 94.96 2.05 8.17 1

PIT-VCV-0025 96.17 1.75 7.43 1

PIT-VCV-0026 92.89 2.65 5.36 1

PIT-VCV-0027 99.08 4.96 8.24 1

PIT-VCV-0028 99.07 6.52 8.88 1

PIT-VCV-0029 98.65 6.9 8.55 1

PIT-VCV-0030 97.62 2.2 8.36 1

Samples from the open pit

PIT-VTM-0001 98.62 5.08 1

PIT-VTM-0002 99.48 6.72 1

Questa Pit Alteration scar

QPS-AAF-0001 97.1 46.5 39.8 3.09 1

QPS-AAF-0003 90.1 36.5 37 3.19 1

QPS-AAF-0005 97 43.1 38.7 2.98 1

 

129

Sample Slake Durability Index %

Point Load Index (MPa)

Peak Friction Angle (degrees)

Ultimate Friction Angle (degrees)

Paste pH SWI

QPS-AAF-0009 94.9 41.7 35.8 2.96 1

QPS-AAF-0020 94.69 2.57 41.9 36.4 2.6 1

QPS-AAF-0022 94.41 2.52 39 39.3 2.56 1

QPS-SAN-0002 92.39 3.5 38.4 34 2.84 1

QPS-VTM-0001 95.23 1.71 34.9 34.6 2.59 1

Outcrop samples

ROC-KMD-0001 99.51 38.7 35.9 6.8 1

ROC-KMD-0002 99.61 6.62 1

ROC-VTM-0032 98.29 41.2 39.7 6.37 5

Straight Creek scar

SCS-LFG-0004 73.9 37.7 37.5 2.5 5

SCS-LFG-0005 92.43 42.9 44.8 2.72 5

SCS-LFG-0006 98.49 38.3 34.6 2.67 4

SCS-LFG-0007 98.5 45.7 37.9 3.21 5

SCS-LFG-0008 96.31 2.42 2

Spring Gulch and Blind Gulch rockpiles

SPR-AAF-0001 97.21 3.92 38.9 36.3 3.48 1

SPR-AAF-0003 90.68 4.8 49.3 38.7 3.66 2

SPR-SAN-0002 97.96 2.08 38.1 34.2 4.22 5

SPR-VTM-0005 98.64 2.81 36.1 34.9 5.26 5

SPR-VTM-0008 98.49 3.39 40.4 35.8 6.22 5

SPR-VTM-0010 97.82 1.34 40.3 39.9 6.56 4

SPR-VTM-0012 96.9 42 38.5 3.29 4

SPR-VTM-0014 98.21 38.8 39.5 3.28 2

SPR-VTM-0017 67.67 39.2 37.3 2.84 2

SPR-VTM-0021 96.84 2.6 35.9 32.8 2.43 2

Sugar Shack South rock pile

SSS-AAF-0001 94.54 47.3 39.7 2.7 2

SSS-AAF-0004 96.94 1.62 41.1 38 2.65 2

SSS-AAF-0005 96.49 1.03 43.3 41.2 2.48 2

SSS-AAF-0007 93.12 2.19 43.7 38.6 2.48 2

SSS-AAF-0009 94.41 45 41.9 2.19 2

SSS-AAF-0011 85.33 2.54 2

SSS-AAF-0012 97.21 2.08 2.44 2

SSS-EHP-0002 98.45 6.17 2

SSS-EHP-0003 98.87 6.52 2

SSS-EHP-0011 98.66 7.41 2

SSS-EHP-0012 98.27 7.44 4

SSS-EHP-0014 99.13 2.45 6.6 4

SSS-EHP-0015 99.28 6.46 4

SSS-EHP-0017 99.16 4.4 4

SSS-EHP-0019 99.18 4.08 3

 

130

Sample Slake Durability Index %

Point Load Index (MPa)

Peak Friction Angle (degrees)

Ultimate Friction Angle (degrees)

Paste pH SWI

SSS-EHP-0020 97.28 4.21 3

SSS-EHP-0023 39.71 3.92 3

SSS-EHP-0025 98.95 4.01 3

SSS-EHP-0031 99.28 3.18 3

SSS-EHP-0032 99.52 3.52 3

SSS-EHP-0033 99.35 4.67 3

SSS-EHP-0034 99.5 5.71 3

SSS-EHP-0036 99.13 2.86 3

SSS-VEV-0001 90.76 4.26 3

SSS-VTM-0012 96.8 2.19 4.13 3

SSS-VTM-0600 96.8 38.9 35.9 4.49 3

Sugar Shack West rock pile

SSW-AAF-0001 97.07 4.37 45.7 40.3 3.01 3

SSW-AAF-0002 96.09 41.9 38.6 2.36 3

SSW-AAF-0005 82.3 1.68 42.1 37.5 2.95 3

SSW-AAF-0007 95.21 5.3 44.6 41.6 3.09 3

SSW-AAF-0009 4.01 3

SSW-SAN-0002 96.07 2.51 41.6 39.8 2.9 3

SSW-SAN-0006 95.18 2.03 35.3 35.5 2.4 4

SSW-VTM-0001 98.61 41.8 35.5 2.64 4

SSW-VTM-0016 97.51 4.4 42.6 39.2 5.58 4

SSW-VTM-0019 98.5 5.02 39.5 35.7 4.35 3

SSW-VTM-0022 98.61 4.57 5.21 2

SSW-VTM-0023 98.44 5.2 39.7 37.3 5.22 2

SSW-VTM-0026 97.86 41.1 41.2 2.44 2

SSW-VTM-0028 97.15 6.06 47.9 39.4 2.39 2

SSW-VTM-0030 96.63 4.19 37 37 3.58 2

Southwest Hansen alteration scar

SWH-GJG-0008 76.12 2.36 2

SWH-GJG-0009 64.52 2.37 3

SWH-GJG-0012 92.36 35.1 35.2 2.41 2

SWH-GJG-0015 96.16 2.64 5

Table B2: Summary of location of samples tested for point load and slake durability. Sample identification number

Trench, test pit, or drill hole identification number

Sample description

UTM easting (m)

UTM northing (m)

Elevation (ft)

Sample location

GHN-EHP-0001 LFG-017 soil 453688 4062313.3 9651.2 top layer GHN-EHP-0002 LFG-017 soil 453690.9 4062314.5 9651.2 15-25 ft, lowest layer GHN-EHP-0003 LFG-013 soil 453678.4 4062414.8 9712.1 0-3 ft GHN-EHP-0004 LFG-013 soil 453680.9 4062415.8 9712.1 GHN-EHP-0005 LFG-013 soil 453681.7 4062416.1 9712.1 N wall GHN-EHP-0006 LFG-013 soil 453681.2 4062415.9 9712.1 N wall

 

131

Sample identification number

Trench, test pit, or drill hole identification number

Sample description

UTM easting (m)

UTM northing (m)

Elevation (ft)

Sample location

GHN-EHP-0007 LFG-013 soil 453681.2 4062415.9 9712.1 N wall GHN-HRS-0096 LFG-012 soil 453693.1 4062353.7 9692.7 GHN-JRM-0001 soil 453710 4062089 9764 in yellow-orange red material from north

tensiometer pit, 60-70 cm below ground level GHN-JRM-0002 soil 453710 4062089 9764 in gray material from north tensiometer pit, 70-80

cm below ground level GHN-JRM-0022 LFG-009 soil 453649.8 4062137.5 9605.1 bench 22, N Wall, 86 ft from 22NW GHN-JRM-0027 LFG-009 soil 453644.7 4062115.3 9599.3 bench 23, 80ft from 23SW, S wall GHN-JRM-0031 LFG-009 soil 453645 4062115.3 9598.5 unit O right above GHN-JRM-0030 GHN-JRM-0037 LFG-011 soil 453664.8 4062334.2 9666.5 GHN-JRM-0038 LFG-011 soil 453670.1 4062340 9666.5 GHN-JRM-0039 LFG-011 soil 453670.8 4062334.3 9659 GHN-JRM-0040 LFG-011 soil 453670 4062333.4 9659 GHN-JRM-0047 LFG-011 soil 453669.4 4062334.8 9663.1 GHN-KMD-0013 LFG-006 soil 453711.1 4062142.2 9734.1 Bench 9, N wall, 52ft E of 9NW peg GHN-KMD-0014 LFG-006 soli 453717.8 4062144.5 9737.2 Bench 8, N wall, 33ft 8NW peg GHN-KMD-0015 LFG-006 soil 453722.7 4062141.5 9735.8 Bench 9, N wall, 90-95ft E of 9NW GHN-KMD-0016 LFG-006 soil 453725.1 4062141.4 9736.1 Bench 9, N wall, 98-105 ft E of 9NW peg, 10ft W

of 8NE GHN-KMD-0017 LFG-006 soil 453695.9 4062143.2 9730.9 Bench 9, N wall, 2ft E of 9NW peg GHN-KMD-0018 LFG-006 soil 453698.2 4062143.2 9730.5 Bench 9, N wall, 10ft E of 9NW peg GHN-KMD-0019 LFG-006 soil 453726.7 4062144.1 9738.6 Bench 8, N wall, 63 ft 8NW GHN-KMD-0026 LFG-006 soil 453728.8 4062141.1 9736.1 bench 9, N wall, 110 ft 9NW GHN-KMD-0027 LFG-006 soil 453707.9 4062147.9 9738.5 bench 7, Nwall, 10 ft 7NW GHN-KMD-0028 LFG-006 soil 453706.9 4062141.6 9726.8 bench 10, S wall, 3 ft GHN-KMD-0048 LFG-007 soil 453691.8 4062131.5 9688.4 bench 15 north wall, 52 ft 15NW GHN-KMD-0050 LFG-007 soil 453704.2 4062145.4 9702.8 floor of bench 12, 84 ft east of 12NW GHN-KMD-0051 LFG-007 soil 453695.1 4062145.8 9698 bench 12, 54 ft east 12NW GHN-KMD-0052 LFG-007 soil 453692.6 4062145.9 9697 floor bench 12, 46 ft east 12NW GHN-KMD-0053 LFG-007 soil 453684.7 4062146.2 9693.7 floor bench 12, 20 ft east 12NW GHN-KMD-0054 LFG-007 soil 453682 4062146.3 9692.6 floor bench 12, 11 ft east 12NW GHN-KMD-0055 LFG-007 soil 453676.5 4062146.5 9691.3 floor bench 12, -7 ft east 12NW GHN-KMD-0056 LFG-007 soil 453704.9 4062139.5 9696.9 bench 14, north wall, 97 ft 14NW GHN-KMD-0057 LFG-007 soil 453695.8 4062139.9 9694 bench 14, north wall, 67 ft from 14NW GHN-KMD-0062 LFG-007 soil 453682.4 4062140.5 9689.8 bench 14, north wall, 23 ft from 14NW GHN-KMD-0063 LFG-007 soil 453677.2 4062140.7 9688.1 bench 14, north wall, 6 ft from 14NW GHN-KMD-0064 LFG-007 soil 453694.9 4062131.9 9690.1 bench 15, north wall, 57 ft from 15NW GHN-KMD-0065 LFG-007 soil 453698.9 4062131.7 9691.5 bench 15, north wall, 70 ft from 15NW GHN-KMD-0071 LFG-008 soil 453678.7 4062137.5 9649.2 bench 18, north wall, 97 ft 18NW GHN-KMD-0072 LFG-008 soil 453671.4 4062137.4 9646.1 bench 18, north wall, 73 ft 18NW GHN-KMD-0073 LFG-008 soil 453666.8 4062137.4 9644.1 bench 18, north wall, 58 ft 18NW GHN-KMD-0074 LFG-008 soil 453680.2 4062137.5 9649.8 bench 18, north wall, 102 ft 18NW GHN-KMD-0077 LFG-008 soil 453670.2 4062134.1 9643.7 bench 19, south wall, 71 ft 19SW GHN-KMD-0078 LFG-008 soil 453671.7 4062134.1 9644.4 bench 19, south wall, 76 ft 19SW GHN-KMD-0079 LFG-008 soil 453679.3 4062137.5 9651.9 bench 18, north wall, 99 ft 18NW GHN-KMD-0080 LFG-008 soil 453677.5 4062137.5 9650.7 bench 18, north wall, 938 ft 18NW GHN-KMD-0081 LFG-008 soil 453675.9 4062137.5 9650 bench 18, north wall, 88 ft 18NW GHN-KMD-0082 LFG-008 soil 453656 4062127 9635.3 bench 20, south wall, 42 ft 20NW GHN-KMD-0088 LFG-008 soil 453657.4 4062127.1 9635.4 bench 20, south wall, 36 ft 20SW GHN-KMD-0090 LFG-008 soil 453655 4062126.9 9634.2 bench 20, south wall, 28 ft 20SW GHN-KMD-0092 LFG-008 soil 453661.9 4062133.8 9640 bench 19, north wall, 44 ft 19SW

 

132

Sample identification number

Trench, test pit, or drill hole identification number

Sample description

UTM easting (m)

UTM northing (m)

Elevation (ft)

Sample location

GHN-KMD-0095 LFG-008 soil 453656 4062118.6 9638.6 15 ft from 17SW, bench 18, south wall GHN-KMD-0096 LFG-008 soil 453658.4 4062118.8 9640.3 23 ft from 17SW, bench 18, south wall GHN-KMD-0097 LFG-008 soil 453658.4 4062118.8 9640.3 GHN-LFG-0018 LFG-0003 soil 453747 4062150 9746 top of GHN GHN-LFG-0020 LFG-0003 soil 453747 4062150 9746 top of GHN GHN-LFG-0037 LFG-0004 soil 453742.8 4062149 9744.2 1 bench of test pit LFG-0004, see test pit log for

more informations GHN-LFG-0041 LFG-0003 soil 453759.7 4062146.9 9736 45.6 ft from point 11 of neutron density probe

measurements GHN-LFG-0057 LFG-005 soil 453733.8 4062146 9765.1 1st bench, north wall, 84 ft east of NW0 GHN-LFG-0060 LFG-005 soil 453720.5 4062141 9749.9 bench 4 GHN-LFG-0085 LFG-005 soil 453731.4 4062143.3 9759.7 bench 3, 47 ft from 3NW GHN-LFG-0086 LFG-005 soil 453731.4 4062143.3 9759.7 bench 3, 47 ft from 3NW GHN-LFG-0088 LFG-005 rock 453734.1 4062140.3 9755 bench 4, 44-45 ft from 4NW GHN-LFG-0089 LFG-005 soil 453747.8 4062137.6 9752.4 bench 4, 90-105 ft from 4NW GHN-LFG-0090 LFG-005 soil 453740.1 4062141.8 9758 bench 3, 76 from 3NW GHN-LFG-0091 LFG-005 soil 453759.8 4062135.3 9749.2 bench 4 GHN-RDL-0002 soil 453791 4062312 9853 GHN-SAW-0002 LFG-018 soil 453680.1 4062296.6 9615.2 GHN-SAW-0003 LFG-018 soil 453682.1 4062296.6 9615.2 GHN-SAW-0004 LFG-011 soil 453657.3 4062290.3 9609.6 GHN-SAW-0005 LFG-011 soil 453650.6 4062281.8 9609.6 GHN-SAW-0200 LFG-021 453650.5 4062394.3 9623.4 GHN-SAW-0201 LFG-022 453647 4062393.8 9648.2 GHN-VTM-0200 LFG-006 soil 453704.4 4062142.6 9735.2 Bench 9, North Face, 30-35 ft 9NW GHN-VTM-0201 LFG-006 soil 453708.8 4062145.2 9735.5 Bench 8, North Face, 6-12 ft 8NW GHN-VTM-0293 LFG-007 soil 453673.3 4062140.8 9686.9 bench 14 N wall -7 to -2 ft from 14 NW peg GHN-VTM-0450 LFG-009 soil 453647.7 4062115.6 9600.7 bench 23 S wall, 90 ft from 23SW GHN-VTM-0453 LFG-009 soil 453643.3 4062115.1 9598.7 bench 23 S wall, 75 ft and 5inches from 23SW GHN-VTM-0456 LFG-005 soil 453764.3 4062134.4 9749.3 natural ground surface, yellow material GHN-VTM-0508 LFG-010 rock 453687.5 4062400 9740 S wall, 60 ft west of SE corner GHN-VTM-0554 LFG-015 rock 453688.1 4062390.2 9708.7 N wall GHN-VTM-0598 LFG-019 rock 453661.6 4062434.8 9651.2 north wall GHN-VTM-0599 LFG-019 rock 453661.6 4062434.8 9651.2 north wall GHN-VTM-0603 LFG-019 soil 453661.6 4062434.8 9651.2 north wall GHN-VTM-0606 LFG-022 soil 453648 4062394.8 9648.2 same as GHN-VTM-0623 GHN-VTM-0607 LFG-022 soil 453647 4062393.8 9648.2 same as GHN-VTM-0622 GHN-VTM-0614 LFG-021 soil 453652 4062391.7 9647.4 GHR-VWL-0001 rock 453071 4061295 8966 large ferricrete on east slope of Goathill scar GHR-VWL-0002 rock 453071 4061293 8966 base of ferricrete GHS-VWL-0004 rock 453101 4061551 8494 contact of amalia tuff and a breccia on side of

alteration scar HAS-GJG-0007 Scar

outcrop 459288 4062957 8880 in gully of scar

HAS-GJG-0010 rock 459288 4062957 8880 scar gully HAS-GJG-0014 GJG-001 rock and

soil 459297 4062858 Hanson scar

MID-AAF-0001 soil 454394 4060686 9431 near MID-KXB-0003 MID-VTM-0002 soil 454395 4060694 9441 near MID-KXB-0003 MIN-AAF-0001 colluvium 452374 4059911 7904 in forest SW of gas pipeline to admin bldg MIN-AAF-0006 colluvium 452374 4059912 7904 in forest SW of gas pipeline to admin bldg

 

133

Sample identification number

Trench, test pit, or drill hole identification number

Sample description

UTM easting (m)

UTM northing (m)

Elevation (ft)

Sample location

MIN-AAF-0010 debris flow

452366 4059925 7900 west of MIN-AAF-0001

MIN-AAF-0012 452363 4059922 7861 west of MIN-AAF-0001 MIN-AAF-0013 debris

flow 452374 4059930 7858 north of MIN-AAF-0012

MIN-AAF-0015 debris flow

452366 4059925 7900 north of MIN-AAF-0012

MIN-GFA-0001 debris flow

452331 405989 7791

MIN-GFA-0003 debris flow

452331 4059891 7791

MIN-GFA-0005 452331 4059891 7791 MIN-GFA-0006 debris

flow 452331 4059891 7791

MIN-GFA-0007 debris flow

452331 405989 7791

MIN-GFA-0009 452331 405989 7791 MIN-SAN-0001 debris

flow 452369 4059919 7966 debris flow, site of in situ test MIN-AAF-0001

MIN-VTM-0002 soil along road above headframe, below powerline, alunite outcrop

MIN-VTM-0003 VTM-001 colluvium 455648.3 4060959.7 8120 MIN-VTM-0004 VTM-001 colluvium 455648.3 4060959.7 8120 MIN-VTM-0006 VTM-001 colluvium 455648.3 4060959.7 8120 MIN-VTM-0007 VTM-001 colluvium 455648.3 4060959.7 8120 MIN-VTM-0008 VTM-001 colluvium 455648.3 4060959.7 8120 MIN-VTM-0009 VTM-001 colluvium 455648.3 4060959.7 8120 PIT-LFG-0011 soil 453845 4061403 9932 PIT-LFG-0013 soil 453659 4061819 9947 Crest of Goathill North Scar PIT-RDL-0002 rock 453822 4061505 9912 PIT-VCV-0001 538420 core 453678.2 4061878.7 9630 core shed PIT-VCV-0002 538420 core 453678.2 4061878.7 9625 core shed PIT-VCV-0003 315328 core 453086.6 4061207.8 8557 core shed PIT-VCV-0004 538420 core 453678.2 4061878.7 9901 core shed PIT-VCV-0005 538420 core 453678.2 4061878.7 9911 core shed PIT-VCV-0006 538420 core 453678.2 4061878.7 9918 core shed PIT-VCV-0007 538420 core 453678.2 4061878.7 9318 core shed PIT-VCV-0008 538420 core 453678.2 4061878.7 9315 core shed PIT-VCV-0009 538420 core 453678.2 4061878.7 9305 core shed PIT-VCV-0010 538420 core 453678.2 4061878.7 8819 core shed PIT-VCV-0011 538420 core 453678.2 4061878.7 8827 core shed PIT-VCV-0012 538420 core 453678.2 4061878.7 9490 core shed PIT-VCV-0013 538420 core 453678.2 4061878.7 9479 core shed PIT-VCV-0014 538420 core 453678.2 4061878.7 9471 core shed PIT-VCV-0015 631587 core 454185.6 4062158.5 8140 core shed PIT-VCV-0016 631587 core 454185.6 4062158.5 8346 core shed PIT-VCV-0017 631587 core 454185.6 4062158.5 8175 core shed PIT-VCV-0018 631587 core 454185.6 4062158.5 8182 core shed PIT-VCV-0019 480680 core core shed PIT-VCV-0020 480680 core core shed PIT-VCV-0021 480680 core core shed PIT-VCV-0022 480680 core core shed PIT-VCV-0023 480680 core core shed

 

134

Sample identification number

Trench, test pit, or drill hole identification number

Sample description

UTM easting (m)

UTM northing (m)

Elevation (ft)

Sample location

PIT-VCV-0024 480680 core core shed PIT-VCV-0025 590539 core 454039.9 4062034.6 9276 core shed PIT-VCV-0026 590539 core 454039.9 4062034.6 9273 core shed PIT-VCV-0027 590539 core 454039.9 4062034.6 9543 core shed PIT-VCV-0028 590539 core 454039.9 4062034.6 7667 core shed PIT-VCV-0029 590539 core 454039.9 4062034.6 9076 core shed PIT-VCV-0030 590539 core 454039.9 4062034.6 9067 core shed PIT-VTM-0001 rock 453800 4061694 top of pit PIT-VTM-0002 rock 443841 4061908 top of pit QPS-AAF-0019 alteration

scar 454135 4062582 9467 bench above pit

QPS-AAF-0020 alteration scar

454135 4062582 9467 bench above pit

QPS-AAF-0022 alteration scar

454135 4062582 9467 bench above pit

QPS-SAN-0001 waste rock 454146 4062551 9581 pit scar in between 2 in-situ test pits QPS-VTM-0001 alteration

scar 454122 4062568 9463 bench above pit

ROC-KMD-0001 soil La Bocita campground at base of andesite outcrop ROC-KMD-0002 rock La Bocita campground at base of andesite outcrop ROC-VTM-0032 soil 466507 4055963 9404 Fourth of July Canyon SCS-LFG-0004 soil 459926 4064047 9429 SCS-LFG-0005 soil 459973 4063905 9433 SCS-LFG-0006 soil 459973 4063905 9433 SCS-LFG-0007 soil 459973 4063905 9433 SCS-LFG-0008 rock 459973 4063905 9433 SGS-KXB-0002 COP-10 cuttings 455469.2 4061388 8435.89 SGS-KXB-0004 COP-10 cuttings 455469.2 4061388 8545.89 SGS-KXB-0006 COP-10 cuttings 455469.2 4061388 8545.89 SGS-KXB-0013 COP-10 cuttings 455469.2 4061388 8235.89 SGS-KXB-0033 COP-7 cuttings 455515.3 4061227.5 8404.23 SGS-LFG-0001 LFG-0001 soil 455162 4061343 Sulphur Gulch South SPR-AAF-0001 waste rock 455245 4062313 9225 SPR-AAF-0003 455245 4062313 9225 SPR-SAN-0001 rock pile 455255 4062285 9314 near in-situ test SPR SPR-VTM-0005 waste rock 455255 4062367 9320 top of Spring Gulch at bend in road SPR-VTM-0008 waste rock 455257 4062287 9322 top of Spring Gulch at bend in road SPR-VTM-0010 waste rock 455257 4062287 9322 top of Spring Gulch at bend in road SPR-VTM-0011 waste rock 455257 4062287 9322 top of Spring Gulch at bend in road SPR-VTM-0014 waste rock 454439 4062735 9539 Spring Gulch near old powder magazine SPR-VTM-0017 waste rock 454439 4062735 9539 Spring Gulch near old powder magazine SPR-VTM-0019 waste rock 454440 4062735 9539 Spring Gulch near old powder magazine SPR-VTM-0021 waste rock 454440 4062735 9539 Spring Gulch near old powder magazine SSSAAF-0001 waste rock 454131 4060898 9636 top of SSS SSS-AAF-0004 waste rock 454131 4060898 9636 top of SSS SSS-AAF-0005 waste rock 454132 4060901 9647 top of SSS SSS-AAF-0007 waste rock 454132 4060901 9647 top of SSS SSS-AAF-0009 waste rock 454132 4060902 9647 top of SSS SSS-AAF-0011 waste rock 454132 4060901 9647 top of SSS SSS-AAF-0012 waste rock 454132 4060902 9624 top of SSS SSS-EHP-0001 SI-50 cuttings 454404 4060242 8756 Sugar Shack South rock pile, lower bench

 

135

Sample identification number

Trench, test pit, or drill hole identification number

Sample description

UTM easting (m)

UTM northing (m)

Elevation (ft)

Sample location

SSS-EHP-0002 SI-50 cuttings 454404 4060242 8747 Sugar Shack South rock pile, lower bench SSS-EHP-0003 SI-50 cuttings 454404 4060242 8737 Sugar Shack South rock pile, lower bench SSS-EHP-0006 SI-50 cuttings 454404 4060242 8707 Sugar Shack South rock pile, lower bench SSS-EHP-0011 SI-50 cuttings 454404 4060242 8667 Sugar Shack South rock pile, lower bench SSS-EHP-0012 SI-50 cuttings 454404 4060242 8657 Sugar Shack South rock pile, lower bench SSS-EHP-0014 SI-50 cuttings 454404 4060242 8637 Sugar Shack South rock pile, lower bench SSS-EHP-0015 SI-50 cuttings 454404 4060242 8627 Sugar Shack South rock pile, lower bench SSS-EHP-0016 SI-50 cuttings 454404 4060242 8617 Sugar Shack South rock pile, lower bench SSS-EHP-0017 SI-50 cuttings 454404 4060242 8607 Sugar Shack South rock pile, lower bench SSS-EHP-0019 SI-50 cuttings 454404 4060242 8587 Sugar Shack South rock pile, lower bench SSS-EHP-0020 SI-50 cuttings 454404 4060242 8577 Sugar Shack South rock pile, lower bench SSS-EHP-0021 SI-50 cuttings 454404 4060242 8567 Sugar Shack South rock pile, lower bench SSS-EHP-0022 SI-50 454404 4060242 8567 Sugar Shack South rock pile, lower bench SSS-EHP-0023 SI-50 cuttings 454404 4060242 8547 Sugar Shack South rock pile, lower bench SSS-EHP-0025 SI-50 cuttings 454404 4060242 8527 Sugar Shack South rock pile, lower bench SSS-EHP-0029 SI-50 cuttings 454404 4060242 8497 Sugar Shack South rock pile, lower bench SSS-EHP-0030 SI-50 cuttings 454404 4060242 8487 Sugar Shack South rock pile, lower bench SSS-EHP-0031 SI-50 cuttings 454404 4060242 8477 Sugar Shack South rock pile, lower bench SSS-EHP-0032 SI-50 cuttings 454404 4060242 8467 Sugar Shack South rock pile, lower bench SSS-EHP0033 SI-50 cuttings 454404 4060242 8457 Sugar Shack South rock pile, lower bench SSS-EHP-0034 SI-50 cuttings 454404 4060242 8447 Sugar Shack South rock pile, lower bench SSS-EHP-0036 SI-50 cuttings 454404 4060242 8427 Sugar Shack South rock pile, lower bench SSS-VEV-0001 rock 454286 4060187 8756 same as SSS-JMS-0001, lower lysimeter SSS-VTM-0010 waste rock 454120 4060712 9703 near repeater site on SSS SSS-VTM-0012 waste rock 454110 4060712 9696 near repeater site on SSS SSS-VTM-0600 waste rock 454120 4060712 9703 near repeater site on SSS SSW-AAF-0001 waste rock 453672 4060616 9022 middle road near drill hole 39-93 SSW-AAF-0002 waste rock 453672 4060617 9028 middle road near drill hole 39-93 SSW-AAF-0005 waste rock 453699 4060554 9038 middle road, south end SSW-AAF-0007 waste rock 453687 4060551 8997 Middle road SSW-SAN-0001 waste rock 453682 4060534 8969 SSW-SAN-0007 453975 4060822 9676 from the same location as SSW-SAN-0005 SSW-VTM-0001 waste rock 453963 4060829 9656 edge of SSW SSW-VTM-0002 waste rock 453963 4060829 9656 edge of SSW SSW-VTM-0016 waste rock 453841 4060491 9326 SSW-VTM-0019 waste rock 453841 4060491 9326 SSW-VTM-0022 waste rock 453838 4060499 9322 SSW-VTM-0023 waste rock 453838 4060499 9322 SSW-VTM-0026 waste rock 453832 4060592 9520 SSW-VTM-0028 waste rock 453832 4060592 9520 SSW-VTM-0030 waste rock 453831 4060588 9520 SWH-GJG-0008 rock 458732 4062439 8710 arroyo, SWH scars SWH-GJG-0009 rock 458732 4062439 8710 Lower SWH SWH-GJG-0012 rock with

soil 458732 4062439 8721 Lower SWH

SWH-GJG-0015 rock with soil

458732 4062439 8746 Lower SWH

 

136

Table B3: Summary of hand specimen descriptions of samples tested for point load and slake durability.

Sample identification number

Field description Color Grain size Alteration

GHN-EHP-0001 unit AE orange brown sandy gravel with clay oxidized GHN-EHP-0002 unit AF gray with little yellow sandy gravel weathered GHN-EHP-0003 rubble zone yellow sandy gravel with cobbles, clay oxidized GHN-EHP-0004 colluvium possible shear black silt-clay with organics GHN-EHP-0005 colluvium gryey bron sandy clay weathered GHN-EHP-0006 bedrock gray clay weathered GHN-EHP-0007 bedrock brown sandy gravel weathered GHN-HRS-0096 colluvium yellow fines with g ravel acid weathered GHN-JRM-0001 Unit J orange to yellowish green clayey gravel highly weathered GHN-JRM-0002 Unit N Brown well graded gravel, fine to

coarse gravel propylitic

GHN-JRM-0008 Unit N Dark Brown GHN-JRM-0009 Unit J Light greay (light yellowish) argilic +

weathering GHN-JRM-0022 Unit K grey clay to gravel GHN-JRM-0027 Unit K clay-sand-pebble weathered GHN-JRM-0031 Unit O GHN-JRM-0037 unit AC orange brown less weathered GHN-JRM-0038 unit AD mottled gray, brown, orange yellow brown GHN-JRM-0039 unit AD mottled gray, yellow, brown clayey gravel with cobbles, boulder GHN-JRM-0040 unit AD mottled gray, brown, yellow clayey gravel with cobbles,

boulder oxidized

GHN-JRM-0047 unit AD mottled gray, brown, orange yellow brown GHN-KMD-0013 Unit O dark brown w/ orange clayey gravel weathered GHN-KMD-0014 Unit K dark greenish gray sandy gravel little weathering,

epidote alteration GHN-KMD-0015 Unit R dark brown w/ orange sandy gravel weathered epidote

to iron, Mn oxide GHN-KMD-0016 Unit S brownish gray w/ green sandy gravel epidote GHN-KMD-0017 Unit I, sandy clay w/ some

gravel grayish yellow sandy clay QSP Altered

GHN-KMD-0018 Unit J, clayey gravel with coarse gravel

dark orange brown clayey gravel minor oxidation; Fe, Mn oxides

GHN-KMD-0019 Unit O, clayey gravel with some coarse gravel

grayish brown clayey gravel epidote weathered

GHN-KMD-0026 Unit M orange-brown clayey gravel oxidized GHN-KMD-0027 Unit N dark orange clayey sand with gravel oxidized GHN-KMD-0028 Unit N bright greenish orange clayey gravel oxidized GHN-KMD-0048 Unit S dark brown to black sandy gravel propollytic GHN-KMD-0050 Unit O brown GHN-KMD-0051 Unit O dark brown GHN-KMD-0052 Unit K purplish gray GHN-KMD-0053 contact between Unit N-J brown GHN-KMD-0054 Unit J orange brown GHN-KMD-0055 Unit I yellow brown GHN-KMD-0056 Unit V brown and orange sand gravel with clay weathered GHN-KMD-0057 Unit O brown and greenish gray sandy gravel weathered

proplytitic GHN-KMD-0062 Unit N orange brown sandy gravel with clay weathered GHN-KMD-0063 Unit J orange brown clayey gravel with sand weathered GHN-KMD-0064 Unit U orange brown clayey gravel with sand weathered GHN-KMD-0065 Unit V dark brown to purplish black sandy gravel with some cobbles propolytic

 

137

Sample identification number

Field description Color Grain size Alteration

GHN-KMD-0071 Unit U, V contact brown orange clay to cobble weathered GHN-KMD-0072 coarse zone in Unit O brown cobbles weathered GHN-KMD-0073 Unit O brown cobbles to clay weathered GHN-KMD-0074 Unit U brown GHN-KMD-0077 Unit U dark brown fine sand, clay GHN-KMD-0078 Unit U orange brown clay to large cobble oxidized GHN-KMD-0079 Unit U medium brown, orange clay to large cobble oxidized GHN-KMD-0080 Unit S dark brown GHN-KMD-0081 Unit R brown clay to cobble GHN-KMD-0082 Unit O dark brown clay to cobble GHN-KMD-0088 Unit O yellow orange clay to cobble oxidixed GHN-KMD-0090 Unit O orange brown clay to cobble GHN-KMD-0092 Unit O1 greenish GHN-KMD-0095 Unit C yellow gray clay to gravel GHN-KMD-0096 Unit J GHN-KMD-0097 Unit O GHN-LFG-0018 traffic zone grey orange GHN-LFG-0020 traffic zone GHN-LFG-0037 Unit H orange gravel sand with some fine GHN-LFG-0041 rubble zone brown/olive GHN-LFG-0057 Unit J GHN-LFG-0060 rubble zone GHN-LFG-0085 Unit K gravel with clay and boulders weathered GHN-LFG-0086 Unit N brown orange oxidized GHN-LFG-0088 Unit O brown to gray oxidized GHN-LFG-0089 rubble zone gray to purple GHN-LFG-0090 Unit P brown GHN-LFG-0091 colluvium yellow to green to brown clay to rubble oxidized GHN-RDL-0002 white to light gray gravel with fines QSP GHN-RDL-0003 white to light gray fine porphyritic QSP GHN-SAW-0002 unit AF gray fine GHN-SAW-0003 unit AF gray GHN-SAW-0004 unit AD yellow GHN-SAW-0005 Unit E brown GHN-SAW-0200 colluvium olive gray to dark brown gravel with fines GHN-SAW-0201 colluvium light-medium brown gravel with fines GHN-VTM-0200 Unit N orange brown; clay to

cobbles orange brown clay to cobbles clay oxidized

GHN-VTM-0201 Unit N; clay to boulders (up to 30cm)

light brown to orange clay to boulders oxidized clay

GHN-VTM-0263 Unit I orange yellow with gray clay to large cobbles oxidized GHN-VTM-0293 Unit I GHN-VTM-0450 Unit O dk brown coarse layer weathering GHN-VTM-0453 Unit O (clay rich) orange brown some gray sandy gravel with clay weathering GHN-VTM-0456 weathered bedrock yellowish to greenish brown clay to cobble oxidized GHN-VTM-0508 colluvium brown fine GHN-VTM-0554 bedrock gray to red gray to green gray fine grained GHN-VTM-0598 rubble zone yelow to gray mostly cobbles with some clay-

sand matrix weathered

GHN-VTM-0599 saprolitic bedrock gray clay to gravel weathered GHN-VTM-0603 weathered bedrock black brown clay to cobble weathered GHN-VTM-0606 colluvium brown clay

 

138

Sample identification number

Field description Color Grain size Alteration

GHN-VTM-0607 rubbe zone yellow gray boulders with fines GHN-VTM-0614 colluvium greenish gray to white gray GHR-VWL-0001 reddish brown acid sulfate GHR-VWL-0002 orange brown acid sulfate GHS-VWL-0004 Ferricrete dark brown to orange strong QSP of host

rock HAS-GJG-0006 andesite gry, brown, green QSP, prop HAS-GJG-0007 andesite gray unweathered QSP HAS-GJG-0008 rock fragments and residual

soil brown to tan cobbles with fines

HAS-GJG-0009 gray to white andesite gray, white cobbles with fines QSP HAS-GJG-0010 gray to white andesite gray, white cobbles with fines QSP HAS-GJG-0014 light gray to brown to olive

mottled gravel with slit and some clay qsp

MID-AAF-0001 well graded soil yellow brown gravel with fines QSP of Amalia and prophyry

MID-VTM-0002 yellow brown boulders to clay QSP MIN-AAF-0001 tan gravelly sand with boulders and

fines QSP

MIN-AAF-0006 tan gravelly sand with boulders and fines

QSP

MIN-AAF-0010 well graded debris flow light brown cobbles to clay QSP MIN-AAF-0012 light brown cobbles to clay QSP MIN-AAF-0013 well graded debris flow light brown cobbles to clay QSP MIN-AAF-0015 well graded debris flow light brown cobbles to clay QSP MIN-GFA-0001 well graded brown boulders to clay QSP MIN-GFA-0003 well graded brown boulder to clay QSP MIN-GFA-0005 well graded brow boulders to clay MIN-GFA-0006 poorly graded gravel brown gravel to fine silt QSP MIN-GFA-0007 poorly garded sandy gravel brown cobble to fine silt QSP MIN-GFA-0009 light redish brown coarse gravel to sandy MIN-SAN-0001 well graded light brown cobbles to clay MIN-VTM-0002 rock pink, white fine to coarse acid sulfate MIN-VTM-0003 debris flow, unit A2 light brown cobbles to clay/silt MIN-VTM-0004 debris flow, unit A3 light brown cobbles to clay/silt MIN-VTM-0006 debris flow, unit A5 light brown cobbles to clay/silt MIN-VTM-0007 debris flow, unit A6 light brown cobbles to clay/silt MIN-VTM-0008 debris flow, unit A1 dark brown cobbles to clay/silt MIN-VTM-0009 debris flow, unit A1 light brown cobbles to clay/silt PIT-LFG-0011 dark brown to black sandy, gravel, silty-clay fresh weathered PIT-LFG-0013 yellowish Brown Clay and Sand silty matrix highly weathered PIT-RDL-0002 Amalia light gray fine grained PIT-VCV-0001 andesite gray brown QSP/oxidized PIT-VCV-0002 andesite light green to gray prophylitic PIT-VCV-0003 andesite light green to gray prophylitic PIT-VCV-0004 Amalia white to gray QSP/yellow

oxidation PIT-VCV-0005 Amalia Tuff gray/light yellow slight oxidized PIT-VCV-0006 Amalia Tuff gray-white slight oxidized PIT-VCV-0007 andesite breccia green gray clasts to 2 inch prophylitic PIT-VCV-0008 porphytic andesite gray-green 1-2 mm phenocrysts prophylitic

chlorite PIT-VCV-0009 andesite breccia 1-3 cm prophylitic PIT-VCV-0010 Goat Hill porphyry white gray prophylitic

 

139

Sample identification number

Field description Color Grain size Alteration

PIT-VCV-0011 Goat Hill porphyry white gray 1-5 mm phenocrysts prophylitic chlorite

PIT-VCV-0012 porphyritic andesite green 1-3 mm phenocrysts prophylitic PIT-VCV-0013 porphyritic andesite green gray 1-3 mm phenocrysts prophylitic PIT-VCV-0014 porphyritic andesite gray 1-5 mm phenocrysts QSP, pyrite PIT-VCV-0015 aplite pink prophylitic PIT-VCV-0016 granite pink with black 1-5 mm phenocrysts prophylitic PIT-VCV-0017 andesite gray, slight green fine grained PIT-VCV-0018 granite white, gray, green prophylitic PIT-VCV-0019 andesite gray brown QSP PIT-VCV-0020 andesite gray brown QSP PIT-VCV-0021 andesite gray brown QSP PIT-VCV-0022 andesite gray green prophylitic PIT-VCV-0023 prophylitic andesite green PIT-VCV-0024 andesite breccia green, purple prophylitic PIT-VCV-0025 oxidized porphyry gray, white, brown oxidized PIT-VCV-0026 oxidized porphyry gray, white, brown oxidized PIT-VCV-0027 andesite gray brown QSP PIT-VCV-0028 aplite pink QSP PIT-VCV-0029 andesite gray QSP, pyrite PIT-VCV-0030 andesite gray brown QSP, pyrite,

chlorite, prophylitic

PIT-VTM-0001 mapped as water mellon breccia, part of Christmas Tree porphyry

gray to green fine to medium epidote, chlorite

PIT-VTM-0002 mapped as water mellon breccia, part of Christmas Tree porphyry

gray to green fine to medium epidote, chlorite

QPS-AAF-0019 well graded GWGC yellow brown large rocks to clay QSP QPS-AAF-0020 well graded GWGC yellow brown large rocks to clay QSP QPS-AAF-0022 well graded GWGC brown large rocks to clay QSP QPS-SAN-0001 well graded brown boulders to clay QSP QPS-VTM-0001 well graded GWGC brown large rocks to clay QSP ROC-KMD-0001 soil with large range of

particle size brown gravel with fines prophlytic

ROC-KMD-0002 andesite blue black fine with phenocrysts ROC-VTM-0032 soil with roots black clay to gravel less weathered SCS-LFG-0004 light gray to white with

severe iron stainy along joints Sand/Silty clay QSP Altered

SCS-LFG-0005 light brown with yellow greewish

sand/clayey gravel highly altereted

SCS-LFG-0006 Block size (50mm) indicates degree of weathering

light grey with brown

SCS-LFG-0007 rock with severe iron stainy along joints SCS-LFG-0008 SGS-KXB-0002 gray sand SGS-KXB-0004 gray sand SGS-KXB-0006 gray sand SGS-KXB-0013 yellow brown sand with pebble SGS-KXB-0033 grren and gray coarse sand to gravel prophyitic SGS-LFG-0001 10YR 6/8 2 inches to sand or fine SPR-AAF-0001 brown to dark brown gray GPGC cobbles to fines propyllitic SPR-AAF-0003 matrix supported brown cobbles to fines prop SPR-SAN-0001 well graded brown angular prop

 

140

Sample identification number

Field description Color Grain size Alteration

SPR-VTM-0005 rocky soil dark gray gravel with fines, cobbles argillic SPR-VTM-0008 loose rocky soilwith grass

roots dark gray gravel with fines, cobbles argillic, calcite,

chlorite SPR-VTM-0010 loose rocky soil with grass

roots dark gray gravel with fines, cobbles argillic, calcite,

chlorite SPR-VTM-0011 loose rocky soil with grass

roots dark gray gravel with fines, cobbles argillic, calcite,

chlorite SPR-VTM-0014 weathered rocky soil gray clayey gravel with cobbles QSP SPR-VTM-0017 weathered rocky soil dark gray clayey gravel with cobbles QSP SPR-VTM-0019 rocky clayey soil gray with brown clayey gravel with cobbles QSP SPR-VTM-0021 rocky clayey soil gray with brown clayey gravel with cobbles QSP SSSAAF-0001 rocky light brown cobbles with fines QSP SSS-AAF-0004 light brown cobbles with fines QSP SSS-AAF-0005 orange brown cobbles with fines QSP SSS-AAF-0007 orange brown cobbles with fines QSP SSS-AAF-0009 gray with some brown cobbles with fines QSP SSS-AAF-0011 brown layer of in situ block brown cobbles with fines QSP SSS-AAF-0012 gray with some brown cobbles with fines QSP SSS-EHP-0001 light gray gravel with fines SSS-EHP-0002 light gray gravel with fines SSS-EHP-0003 gray gravel with fines SSS-EHP-0006 gray gravel with fines SSS-EHP-0011 gray gravel with fines SSS-EHP-0012 gray gravel with fines SSS-EHP-0014 gray gravel with fines yellow coatings SSS-EHP-0015 gray gravel with fines SSS-EHP-0016 orange brown sandy gravel SSS-EHP-0017 orange brown sandy gravel SSS-EHP-0019 orange brown gravel with fines SSS-EHP-0020 yellow gray gravel with fines SSS-EHP-0021 yellow gray gravel with fines SSS-EHP-0022 yellow gray gravel with fines SSS-EHP-0023 light gray gravel with fines SSS-EHP-0025 gray gravel with fines SSS-EHP-0029 light gray cobbles with gravel SSS-EHP-0030 gray cobbles with gravel yellow coating SSS-EHP-0031 gray cobbles with gravel yellow coating SSS-EHP-0032 gray cobbles with gravel yellow coating SSS-EHP0033 gray to orange gray gravel with fines yellow coating SSS-EHP-0034 orange gray gravel with a lot of fines SSS-EHP-0036 gray sandy gravel SSS-VEV-0001 ferricrete boulder, probably

from alteration scar befor covering with rock pile

dark orange to brown ferricrete

SSS-VTM-0010 rocky soil brown gray gravel with fines, cobbles argillic, some chlorite

SSS-VTM-0012 loose rock pile material brown gravel with fines, cobbles argillic, some chlorite

SSS-VTM-0600 rocky soil brown gray gravel with fines, cobbles argillic, some chlorite

SSW-AAF-0001 well graded soil brown gravey sand QSP SSW-AAF-0002 select clay lense white gray clayey gravel QSP SSW-AAF-0005 well graded brown cobbles to clay QSP SSW-AAF-0007 well graded brown cobbles to clay QSP

 

141

Sample identification number

Field description Color Grain size Alteration

SSW-SAN-0001 well graded light brown cobbles to clay QSP SSW-SAN-0007 SSW-VTM-0001 rocky soii with clay lenses brown gravel with fines QSP acid

generating SSW-VTM-0002 rocky soii with clay lenses brown gravel with fines QSP acid

generating SSW-VTM-0016 dark gray with some yellow cobbles to clay QSP SSW-VTM-0019 layered, dipping 15 degrees

on north wall dark olive gray to brown with some yellow orange

cobbles to clay QSP

SSW-VTM-0022 layered, dipping 15 degrees on north wall

gray with some yellow orange cobbles to clay QSP

SSW-VTM-0023 layered, dipping 15 degrees on north wall

gray with some yellow orange cobbles to clay QSP

SSW-VTM-0026 yellow orange cobbles to clay QSP SSW-VTM-0028 yellow orange cobbles to clay QSP SSW-VTM-0030 yellow brown cobbles to clay QSP SWH-GJG-0008 bedrock gray QSP SWH-GJG-0009 weathered bedrock brown rock, little fines QSP SWH-GJG-0012 soil to weathered bedrock cobbles to sands QSP SWH-GJG-0015 brown to green gray cobbles with fines

Table B4: Summary of lithology and hydrothermal alteration for samples tested for slake durability and point load.

Sample rhyolite (Amalia Tuff) % Andesite % Intrusive aplite % QSP % Propylitic % Argillic %

GHN-EHP-0007 100

GHN-JRM-0001 100 90 2

GHN-KMD-0013 25 75 30 5 3

GHN-KMD-0014 10 90 25 20

GHN-KMD-0015 0 100 25 12 3

GHN-KMD-0016 0 100 25 20

GHN-KMD-0017 17 83 50 2 20

GHN-KMD-0018 35 65 20 8

GHN-KMD-0019 0 100 10 25

GHN-KMD-0026 60 40 40 1

GHN-KMD-0027 50 50 30 7

GHN-KMD-0051 60 40 25 15 3

GHN-KMD-0052

GHN-KMD-0053 50 50 30 5

GHN-KMD-0054

GHN-KMD-0055 20 80 50

GHN-KMD-0056 70 30 30 7 2

GHN-KMD-0057 100 15 40

GHN-KMD-0065 60 40 20 5

GHN-KMD-0071 40 30 30 25 10

GHN-KMD-0072

GHN-KMD-0073 10 90 25 12 2

GHN-KMD-0074 20 80 35 10

 

142

Sample rhyolite (Amalia Tuff) % Andesite % Intrusive aplite % QSP % Propylitic % Argillic %

GHN-KMD-0079 20 80 50 7 3

GHN-KMD-0080

GHN-KMD-0081 50 50 55 10 3

GHN-KMD-0082 95 5 30 15

GHN-KMD-0088 100 60 10

GHN-KMD-0096 100 0 70

GHN-KMD-0097 60 2

GHN-LFG-0085 90 10 25 2 4

GHN-LFG-0086

GHN-LFG-0088 0 100 25 12 3

GHN-LFG-0089

GHN-LFG-0090 0 100 25 8 3

GHN-LFG-0091 100 0 70 6

GHN-RDL-0002 100

GHN-RDL-0003 100

GHN-VTM-0263 12 88 3 55

GHN-VTM-0450 10 80 10 15 8 5

GHN-VTM-0453 0 75 25 55 15 4

GHN-VTM-0456 100

GHN-VTM-0508 0 100 40 10

GHN-VTM-0554 100

GHN-VTM-0599 100 75

GHN-VTM-0603 75 5

GHN-VTM-0606 75 25 40 20

GHN-VTM-0614 0 100 70 25

MIN-GFA-0001 1 99 65 5

MIN-GFA-0003 100 85 2

MIN-GFA-0005 99 1 70 10

MIN-GFA-0009 100 70

MIN-SAN-0002 5 95 30 3

MIN-VTM-0003 100

PIT-LFG-0013 100

PIT-RDL-0002 100

PIT-VCV-0001 100 25 1

PIT-VCV-0002 100 80

PIT-VCV-0003 100 40 5

PIT-VCV-0004 100 60

PIT-VCV-0005 100 20

PIT-VCV-0006 100 25

PIT-VCV-0007 100 40 5

PIT-VCV-0008 100 10 20

PIT-VCV-0009 100 20 15

 

143

Sample rhyolite (Amalia Tuff) % Andesite % Intrusive aplite % QSP % Propylitic % Argillic %

PIT-VCV-0010 100 50 10

PIT-VCV-0011 100 60

PIT-VCV-0012 100 60 3

PIT-VCV-0013 100 65

PIT-VCV-0014 100 50

PIT-VCV-0015 100 65

PIT-VCV-0016 100 25

PIT-VCV-0017 100 30

PIT-VCV-0018 100 35

PIT-VCV-0019 100 70

PIT-VCV-0020 100 90

PIT-VCV-0021 100 85

PIT-VCV-0022 100 50

PIT-VCV-0023 100 60

PIT-VCV-0024 100 60

PIT-VCV-0025 100 75

PIT-VCV-0026 100 70

PIT-VCV-0027 100 90

PIT-VCV-0028 100 60

PIT-VCV-0029 100 45

PIT-VCV-0030 100 70

PIT-VTM-0001 100

PIT-VTM-0002 100

QPS-AAF-0001 80 90

QPS-AAF-0003 80 20

QPS-AAF-0005 80 20

QPS-AAF-0009 80 20

QPS-SAN-0002 95 5 30 7

ROC-KMD-0001 100

ROC-KMD-0002 100

ROC-VTM-0032 0 100 8 2

SCS-LFG-0004 0 0 100 32 68

SCS-LFG-0005 0 0 100 30 20

SCS-LFG-0006 0 0 100 45 55

SCS-LFG-0007 100

SCS-LFG-0008 100

SPR-SAN-0002 100 35 7

SPR-VTM-0005 100

SPR-VTM-0008 100

SPR-VTM-0010 100

SPR-VTM-0017 100

SSS-AAF-0004 100

 

144

Sample rhyolite (Amalia Tuff) % Andesite % Intrusive aplite % QSP % Propylitic % Argillic %

SSS-AAF-0005 100

SSS-AAF-0009 100

SSS-EHP-0014 100

SSS-EHP-0015 100

SSS-EHP-0019 100

SSS-EHP-0020 100

SSS-EHP-0023 100

SSS-EHP-0025 100

SSS-VTM-0600 80 20

SSW-AAF-0001 80 20

SSW-AAF-0002 80 20

SSW-AAF-0005

SSW-AAF-0007

SSW-AAF-0009

SSW-SAN-0002 100 25 5

SSW-SAN-0006 95 3 2 50 1

Table B5: Mineralogy in weight percent for samples tested for slake durability and point load, as determined by modified ModAn (McLemore et al., 2009).

Sample Quartz K-feldspar Plagioclase Epidote Calcite Pyrite Fe Oxide Gypsum Molybdenite Biotite

GHN-EHP-0001 35 24 13 0.9 1 2 0.1

GHN-EHP-0002 47 21 1 0.6 0.1 0.9 0.6

GHN-JRM-0001 35 7 15 0.01 0.4 3 1.2 0.01

GHN-KMD-0013

29 20 16 0.2 0.4 0.1 6 1 0.01 0.01

GHN-KMD-0014

19 37 19 9 1.4 0.2 1 0.04 0.01 0.01

GHN-KMD-0015

30 20 15 0.1 1.4 0.1 5 0.7

GHN-KMD-0016

24 22 22 12 0.01 0.2 0.5 1

GHN-KMD-0017

32 3 21 0.1 3 0.6 1.5

GHN-KMD-0018

39 25 4 0.4 0.4 1.7 1.2

GHN-KMD-0019

24 18 24 7 2 0.1 2 0.24

GHN-KMD-0026

36 29 15 0.01 0.3 0.1 4 0.6

GHN-KMD-0027

35 26 11 0.01 0.7 0.01 5 0.6

GHN-KMD-0048

25 24 24 10 0.4 0.1 2

GHN-KMD-0050

25 23 22 8 0.9 0.1 2

GHN-KMD-0051

27 25 19 4 1.8 0.2 3 2

GHN-KMD-0052

29 20 16 3 2.5 2 2 0.4

 

145

Sample Quartz K-feldspar Plagioclase Epidote Calcite Pyrite Fe Oxide Gypsum Molybdenite Biotite

GHN-KMD-0053

38 27 8 1 0.7 0.1 3 0.6

GHN-KMD-0054

28 24 17 5 0.5 0.5 3 1

GHN-KMD-0055

48 14 5 0.5 3 0.7 1

GHN-KMD-0056

30 24 20 3 0.5 0.2 3 0.41

GHN-KMD-0057

26 17 25 7 1 0.2 2

GHN-KMD-0062

35 21 10 1 0.01 5 0.1

GHN-KMD-0063

33 16 13 0.1 0.2 1 4 0

GHN-KMD-0064

33 27 16 2 0.1 0.3 4

GHN-KMD-0065

29 22 17 3 0.4 0.1 5 0.3 0.01

GHN-KMD-0071

30 23 20 2 0.4 0.8 2 0.8

GHN-KMD-0072

27 24 20 6 1 0.1 3

GHN-KMD-0073

25 22 21 5 1 0.3 2 0.4

GHN-KMD-0074

28 21 18 5 0.4 0.2 3 0.4

GHN-KMD-0077

32 26 19 2 0.4 0.1 3.5

GHN-KMD-0078

35 26 18 0.4 0.4 3

GHN-KMD-0079

31 23 17 2 0.5 0.3 4 0.8

GHN-KMD-0080

24 23 23 10 0.4 0.1 2

GHN-KMD-0081

33 21 18 1 0.5 0.6 3 0.7

GHN-KMD-0082

26 23 23 5 1 0.3 2 1.2 0.01

GHN-KMD-0088

29 23 19 0.01 0.2 0.9 3 1.8

GHN-KMD-0092

30 20 17 0.3 0.7 3

GHN-KMD-0095

48 25 0 0.3 0.7 0.2

GHN-KMD-0096

46 19 2 0.01 0.5 0.3 0.4 0.81 0.01

GHN-KMD-0097

39 25 2 0.01 0.3 1 0.4 0

GHN-KMD-0100

34 25 11 0.5 0.01 4

GHN-LFG-0085 27 22 17 7 0.4 0.1 4 0.2

GHN-LFG-0086 26 22 16 7 0.3 2 2 1.7

GHN-LFG-0088 24 24 22 8 2 0.1 2 0.28

GHN-LFG-0089

GHN-LFG-0090 23 21 23 3 1.2 1 4 1.5

GHN-LFG-0091 55 6 4 0.001 1 1 6

GHN-RDL-0002 0.02

GHN-SAW-0200

0.23

GHN-SAW-0201

0.21

 

146

Sample Quartz K-feldspar Plagioclase Epidote Calcite Pyrite Fe Oxide Gypsum Molybdenite Biotite

GHN-VTM-0263

45 14 0.6 0.5 4 0.3 0.7

GHN-VTM-0293

42 14 4 1 3 0.7 2

GHN-VTM-0450

26 20 22 5 0.6 0.4 4 0.01

GHN-VTM-0453

25 20 17 1 1 2 4 2 1

GHN-VTM-0456

GHN-VTM-0508

44 13 11 2 1 3 4.8 0.001

GHN-VTM-0599

30 13 3 0.1 5 0.4 4 0.2

GHN-VTM-0603

33 2 7 0 2 0.01 3 0.4

GHN-VTM-0606

49 12 8 0 0.001 0.001 1 1 0 0.001

GHN-VTM-0607

39 13 9 0.01 0.6 0.4 3 0.6

GHN-VTM-0614

31 1 1 3 0.3 0.1 6

GHR-VWL-0004

28 14 0.1 12

HAS-GJG-0006 21 21 4 4 2 8

HAS-GJG-0007 24 9 5 5 3 12

HAS-GJG-0008 28 6 3 0.4 15

HAS-GJG-0009 25 1 5

HAS-GJG-0010 45 0.2 1 5

MID-AAF-0001 32 13 14 0.1 0.8 4 3

MID-AAF-0002 35 10 9 0.2 0.6 4 3

MID-VTM-0002 49 19 2 0.01 0.2 2 0.01 0.7

MIN-AAF-0001 47 15 0.01 0.1 0.01 2 0.1

MIN-AAF-0004 45 22 0.1 0.1 0.01 2 0.1

MIN-AAF-0010 44 12 0.6 1 0.1 0.7 0.1

MIN-AAF-0013 48 22 0.3 0.01 1 0.08

MIN-GFA-0001 45 18 0.6 0.2 0.1 2 0.01

MIN-GFA-0003 43 16 5 0.5 3 0.3 0.01

MIN-GFA-0005 46 20 0.04 0.1 2 0.04

MIN-GFA-0009 48 16 0.7 0.1 0.1 2 0.1

MIN-SAN-0002 45 13 2 0.1 0.01 1 0.2

PIT-LFG-0013 39 0.6 17 0.3 0.9 0.5

PIT-RDL-0002 46 40 0.1 1

PIT-VCV-0001 25 30 15 0.01 1 7 0.01 0.2

PIT-VCV-0002 37 33 2 5 0.01 0.2

PIT-VCV-0003 23 17 29 0.5 7 0.3

PIT-VCV-0004 59 16 0.1 0.01 1

PIT-VCV-0005 58 12 0.1 0.01 1 0

PIT-VCV-0006 75 7 1E-04

PIT-VCV-0007 30 35 2 0.2 1 4 0.8 0.3 0.01

 

147

Sample Quartz K-feldspar Plagioclase Epidote Calcite Pyrite Fe Oxide Gypsum Molybdenite Biotite

PIT-VCV-0008 41 17 2 0.9 5.3 3.7 0 2

PIT-VCV-0009 31 17 14 1.5 2.1 5.6 0

PIT-VCV-0010 28 32 19 0.01 2 3 0.01 0.2 3

PIT-VCV-0011 30 35 9 2 3 0.01 0.2 5

PIT-VCV-0012 48 18 1 0.01 0.8 3 1 0.1

PIT-VCV-0013 55 10 0.2 0.01 3 2 0.4 0.2

PIT-VCV-0014 47 19 0.2 0.01 2 2 0.7 0.2

PIT-VCV-0015 41 37 15 0.01 0.5 0.6 0.01 0.1 1

PIT-VCV-0016 29 38 14 0.01 2 1E-04

0.2 0.1 1

PIT-VCV-0017 33 38 7 0.01 1 0.9 0.1 0.2 2

PIT-VCV-0018 36 38 11 0.01 2 1 0.01 0.1

PIT-VCV-0019 30 4 0.01 0.1 0.9 1 4

PIT-VCV-0020 24 17 4 5 0.5 2 1 0.5 7

PIT-VCV-0021 23 16 15 0.01 0.05 3 0.01 7 0.03 0

PIT-VCV-0022 23 18 24 0.01 0.1 7 0.01 7 3

PIT-VCV-0023 26 14 18 0.01 0.1 9 0.01 9 0.01 0.01

PIT-VCV-0024 30 21 3 0.01 1 2 0.01 0.6

PIT-VCV-0025 40 18 0.7 0.01 0.8 6 0.01 0.3

PIT-VCV-0026 37 19 1 0.01 0.3 7 0.01 0.4

PIT-VCV-0027 28 28 6 0.01 0.7 5 0.4 0.2

PIT-VCV-0028 38 35 23 0.01 1 4 0.1 0.2 1

PIT-VCV-0029 55 15 6 0.3

PIT-VTM-0001 32 6 30 0.5 0.1 0.1 4

PIT-VTM-0002 23 27 24 11 0.1 0.2 2

QPS-AAF-0001 38 12 13 0.01 0.7 0.2 2 0.9

QPS-AAF-0003 34 10 14 0.1 0.1 3 2

QPS-AAF-0005 34 6 14 0.01 0.09 3 2

QPS-AAF-0009 35 17 6 3 0.3 0.3 3 0.9

QPS-SAN-0002 42 4 10 0.2 0.8 1

QPS-VTM-0001 33 12 16 0.01 0.4 0.2 4 1

ROC-KMD-0002

16 20 36 0.2 6 0.8 0

ROC-VTM-0032 19 18 24 1 6 0.02 1

SCS-LFG-0004 17 0.001 0.001 2 8 13

SCS-LFG-0005 34 6 5 2 0.1 0.3 2.3

SCS-LFG-0006 30 18 21 0.1 0.5 0.1 1 6

SPR-AAF-0001 26 17 24 5 0.6 0.5 2 0.6

SPR-AAF-0003 25 18 22 2 0.4 0.5 4 1

SPR-SAN-0002 25 21 18 2 0.5 0.3 4 2

SPR-VTM-0012 56 11 0.8 0.01 0.1 0.3 0.7 0.04

SPR-VTM-0017 49 18 0.1 0.9 0.3 0.02

SPR-VTM-0021 51 22 0.1 0.2 0.5 0.02

 

148

Sample Quartz K-feldspar Plagioclase Epidote Calcite Pyrite Fe Oxide Gypsum Molybdenite Biotite

SSS-AAF-0001 29 14 7 0.2 0.4 6 3

SSS-AAF-0005 38 4 5 0.01 0.4 4 1.21

SSS-AAF-0009 47 15 1 0.4 0.5 1 0

SSS-VTM-0600 36 17 13 0.2 0.2 4 0

SSW-AAF-0001 25 21 20 0 0.1 0.4 6 0.51

SSW-AAF-0005 33 11 18 0.2 0.2 4 0

SSW-AAF-0007 34 16 10 0.1 1 2 2

SSW-AAF-0009 30 16 16 5 0.3 0.8 1 0 0.01

SSW-SAN-0002 32 8 18 0.01 0.1 0.3 2 2 0.01

SSW-SAN-0006 37 22 2 3 0.3 0.1 0.6 1

SSW-VTM-0001 49 3 6 0.3 0.4 4 2

SSW-VTM-0030 31 8 13 7 0.6 1 1 3.1

SWH-GJG-0008 30 24 22 0.6 7

SWH-GJG-0009 23 13 20 1 12 12

SWH-GJG-0012 30 13 28 0.7 4

SWH-GJG-0015 33 16 4

Sample Fluori

te Magnetite

Apatite

Kaolonite

Chlorite

Illite

Smectite

Copiapite

Jarosite

Sphalerite

Rutile

Zircon

GHN-EHP-0001

0.5 1 3 17 1 0 0.4 0.04

GHN-EHP-0002

0.1 1 2 23 1 2 0.2 0.06

GHN-JRM-0001

0.2 1 3 27 2 4 0.4 0.03

GHN-KMD-0013

0.6 1 3 20 2 0.2 0.01 0.01 0.3 0.03

GHN-KMD-0014

0.7 1 7 1 2 0.2 0.01 0.8 0.03

GHN-KMD-0015

0.6 2 5 16 3 0.14 0.01 0.5 0.03

GHN-KMD-0016

0.7 1 7 4 5 0 0.7 0.03

GHN-KMD-0017

0.4 1 4 25 3 0.06 4 0.01 0.6 0.03

GHN-KMD-0018

0.01 0.2 1 3 19 3 0.06 1.4 0.3 0.04

GHN-KMD-0019

0.6 1 8 9 3 0 0.7 0.03

GHN-KMD-0026

0.3 1 2 10 2 0 0.1 0.04

GHN-KMD-0027

0.5 2 2 15 2 0.3 0.2 0.04

GHN-KMD-0028

GHN-KMD-0048

0.8 1 7 4 1 0.7 0.04

GHN-KMD-0050

0.8 1 7 8 2 0.7 0.03

GHN-KMD-0051

0.4 2 4 8 4 0 0.5 0.04

GHN-KMD-0052

0.7 1 6 16 1 0 0.5 0.03

GHN-KMD-0053

0.01 0.1 2 2 15 2 0.5 0.2 0.06

 

149

Sample Fluorite

Magnetite

Apatite

Kaolonite

Chlorite

Illite

Smectite

Copiapite

Jarosite

Sphalerite

Rutile

Zircon

GHN-KMD-0054

0.01 0.8 1 6 12 1 0.5 0.6 0.03

GHN-KMD-0055

0.03 0.2 1 2 28 1 1 0.3 0.04

GHN-KMD-0056

0.4 1 4 10 4 0 0.5 0.04

GHN-KMD-0057

0.01 0.8 1 7 11 2 0.6 0.03

GHN-KMD-0062

0.2 1 3 20 2 1 0.3 0.04

GHN-KMD-0063

0.3 2 5 20 2 1.6 0.5 0.03

GHN-KMD-0064

0.4 1 2 11 3 0.2 0.04

GHN-KMD-0065

0.5 2 5 14 2 0 0.4 0.04

GHN-KMD-0071

0.3 2 3 13 2 0 0.4 0.03

GHN-KMD-0072

0.7 1 6 8 3 0.5

GHN-KMD-0073

0.5 4 7 8 4 0 0.5 0.03

GHN-KMD-0074

0.5 2 6 12 2 0 0.6 0.03

GHN-KMD-0077

0.4 1 2 11 2 0.2 0.04

GHN-KMD-0078

0.4 2 3 10 2 0.3 0.04

GHN-KMD-0079

0.4 1 4 13 3 0.01 0.4 0.04

GHN-KMD-0080

0.7 3 7 4 3 0.7 0.04

GHN-KMD-0081

0.2 0.5 1 3 14 3 0 0.3 0.04

GHN-KMD-0082

0.6 1 7 8 1 0 0.6 0.03

GHN-KMD-0088

0.2 2 4 14 2 0.1 0.4 0.03

GHN-KMD-0092

0.4 1 4 19 3 0.4 0.03

GHN-KMD-0095

0.01 2 1 20 2 1 0.1 0.06

GHN-KMD-0096

0.1 2 2 23 1 2.5 0.2 0.06

GHN-KMD-0097

0.2 1 3 23 1 2 0.4 0.04

GHN-KMD-0100

0.4 3 4 15 2 0.3 0.04

GHN-LFG-0018

1 2 3 3

GHN-LFG-0020

2 2 3 2

GHN-LFG-0037

1 2 2 4

GHN-LFG-0041

1 1 3 4

GHN-LFG-0085

0.6 1 7 13 1 0 0.6

GHN-LFG-0086

0.7 1 6 13 1 0 0.6 0.03

GHN-LFG-0088

0.7 1 8 7 1 0 0.7

GHN-LFG-0089

 

150

Sample Fluorite

Magnetite

Apatite

Kaolonite

Chlorite

Illite

Smectite

Copiapite

Jarosite

Sphalerite

Rutile

Zircon

GHN-LFG-0090

0.7 1 7 11 2 0 0.6 0.03

GHN-LFG-0091

0.01 17 0

GHN-RDL-0002

3 1 3 2

GHN-SAW-0003

1 0 7

GHN-SAW-0004

1 1 3 3

GHN-SAW-0005

1 3 4 1

GHN-SAW-0200

1 2 4 1

GHN-SAW-0201

2 0 3 2

GHN-VTM-0263

0.3 2 2 29 1 1 0.4 0.04

GHN-VTM-0293

0.3 0 3 28 1 1 0.4 0.04

GHN-VTM-0450

0.6 1 7 10 2 0.6 0.07

GHN-VTM-0453

0.4 1 7 17 1 0 0.6 0.03

GHN-VTM-0508

1 0 14 1 0

GHN-VTM-0554

1 3 3 2

GHN-VTM-0598

1 1 5 1

GHN-VTM-0599

0.5 1 5 36 1 0 0.4 0.03

GHN-VTM-0603

0.01 1 5 41 1 3 0.5 0.03

GHN-VTM-0606

10 0

GHN-VTM-0607

0.2 1 3 27 2 1 0.4 0.04

GHN-VTM-0614

0.01 0.2 1 3 46 1 6 0.7 0.03

GHR-VWL-0004

0.6 1 4 40 1 0.2

HAS-GJG-0006

5 12 14 10 0

HAS-GJG-0007

0 9 24 8 0

HAS-GJG-0008

0 16 32 0 0

HAS-GJG-0009

0 0 69 0 0

HAS-GJG-0010

0 6 37 5 0

HAS-GJG-0014

MID-AAF-0001

0.3 2 3 22 3 0 0.4 0.03

MID-AAF-0002

0.2 0 3 28 3 1 0.3 0.03

MID-VTM-0002

0.1 0.9 0.9 17 6 2 0.2 0.06

MIN-AAF-0001

0.1 2 2 29 1 2 0.3 0.04

MIN-AAF-0004

0.1 1 0 16 3 2 0.2 0.04

 

151

Sample Fluorite

Magnetite

Apatite

Kaolonite

Chlorite

Illite

Smectite

Copiapite

Jarosite

Sphalerite

Rutile

Zircon

MIN-AAF-0006

MIN-AAF-0010

0.002 0.1 1 2 33 1 3 0.5 0.03

MIN-AAF-0012

MIN-AAF-0013

0.01 1 0 20 6 1 0.3 0.06

MIN-AAF-0015

MIN-GFA-0001

0.01 0.1 2 2 28 1 1 0.5 0.04

MIN-GFA-0003

0.01 0.6 2 3 25 1 0.01 0.3 0.03

MIN-GFA-0005

0.01 0.1 0 1 28 2 0 0.3 0.05

MIN-GFA-0009

0.02 0.1 2 1 27 1 1 0.3 0.04

MIN-SAN-0002

0.2 3 2 28 1 3 0.4 0.04

PIT-LFG-0013

0.1 2 3 30 1 5.6 0.6 0.03

PIT-RDL-0002

0.01 1 0.6 10 1 0.1 0.06

PIT-VCV-0001

0.6 0 2 18 0 0 0.7 0.03

PIT-VCV-0002

0.3 0 2 20 0 0 0.4 0.06

PIT-VCV-0003

0.7 0.8 3 18 0.8 0 0.8 0.03

PIT-VCV-0004

0.01 1 1 21 1 0.06 0.1 0.06

PIT-VCV-0005

0.01 1 1 24 1 1 0.1 0.06

PIT-VCV-0006

0.0001 0.5

PIT-VCV-0007

0.01 0.5 1 2 22 1 0.01 0.6 0.04

PIT-VCV-0008

0.5 0.4 0.9 0.3 25 0.9 0.2 0.5

PIT-VCV-0009

1 0.5 0.9 3 22 0.9 0.06 0.6 0.04

PIT-VCV-0010

0.01 0.4 0.9 3 10 0.9 0 0.5 0.04

PIT-VCV-0011

0 0.6 1 3 14 1 0 0.5 0.04

PIT-VCV-0012

0.01 0.2 1 2 24 0.9 0 0.3 0.03

PIT-VCV-0013

0.0001 0.2 0 1 28 0 0 0.3 0.03

PIT-VCV-0014

1 0.01 1 2 26 1 0 0.3 0.03

PIT-VCV-0015

0.0001 0.1 1 0.6 3 1 0 0.2 0.01

PIT-VCV-0016

0.01 0.7 1 3 10 1 0 0.8 0.07

PIT-VCV-0017

0.4 1 2 15 1 0 0.5 0.04

PIT-VCV-0018

0.01 0.4 1 1 9 1 0 0.3 0.03

PIT-VCV-0019

0.4 1 0.4 55 1 3 0.7 0.03

PIT-VCV-0020

0.8 1 0.8 41 1 0 0.8 0.03

 

152

Sample Fluorite

Magnetite

Apatite

Kaolonite

Chlorite

Illite

Smectite

Copiapite

Jarosite

Sphalerite

Rutile

Zircon

PIT-VCV-0021

0.7 1 12 18 1 3 0.9

PIT-VCV-0022

6 1 9 8 1 0.3 0.9 0.03

PIT-VCV-0023

7 1 4 17 1 1 1 0.02

PIT-VCV-0024

2 1 6 32 1 0 0.7 0.03

PIT-VCV-0025

0.4 1 2 29 1 0 0.5 0.04

PIT-VCV-0026

0.4 1 3 29 1 0 0.5 0.04

PIT-VCV-0027

0.5 1 4 25 1 0 0.6 0.03

PIT-VCV-0028

0.4 1 0.4 0.1 1 0 0.2 0.01

PIT-VCV-0029

0.6 0

PIT-VCV-0030

0

PIT-VTM-0001

0.5 1 6 18 1 0.6 0.03

PIT-VTM-0002

0.6 1 6 4 1 0.5 0.03

QPS-AAF-0001

0.4 0 3 27 0 2 0.5 0.03

QPS-AAF-0003

0.4 1 4 28 1 2 0.5 0.03

QPS-AAF-0005

0.4 3 4 29 0.9 3 0.5 0.03

QPS-AAF-0009

0.7 1 3 28 1 0 0.6 0.03

QPS-SAN-0002

0.2 1 3 31 3 4 0.4 0.04

QPS-VTM-0001

0.5 1 3 25 3 0.3 0.4 0.03

ROC-KMD-0001

1 2 4 2

ROC-KMD-0002

0.6 1 5 10 3 0.7 0.8 0.03

ROC-VTM-0032

2 1 0.01 11 16 0 0.4

SCS-LFG-0004

5 5 26 24 0

SCS-LFG-0005

0.3 1 6 35 3 3 0.6 0.03

SCS-LFG-0006

0.3 1 5 19 1 1 0.6 0.03

SCS-LFG-0007

0 2 4 3

SCS-LFG-0008

0 1 7 1

SPR-AAF-0001

0.7 1 10 9 3 0.01 0.7 0.03

SPR-AAF-0003

0.8 1 9 12 3 0 0.7 0.03

SPR-SAN-0002

0.9 1 8 14 3 0.03 0.6

SPR-VTM-0012

0.01 2 0 26 2 0.6 0.1 0.06

SPR-VTM-0014

SPR-VTM-0017

0.02 2 0 24 5 1 0.3 0.04

 

153

Sample Fluorite

Magnetite

Apatite

Kaolonite

Chlorite

Illite

Smectite

Copiapite

Jarosite

Sphalerite

Rutile

Zircon

SPR-VTM-0021

2 0 20 4 0 0.2 0.06

SSS-AAF-0001

0.4 3 6 27 3 0.6 0.4 0.03

SSS-AAF-0004

SSS-AAF-0005

0.3 1 5 36 2 3 0.5 0.04

SSS-AAF-0007

SSS-AAF-0009

0.3 1 0 23 7 2 0.3 0.04

SSS-EHP-0023

1 1 3 3

SSS-VEV-0001

1 2 3 2

SSS-VTM-0600

0.7 7 2 18 1 0.6 0.4 0.04

SSW-AAF-0001

0.9 1 5 14 5 0.5

SSW-AAF-0005

0.01 0.3 1 0.4 25 3 3 0.6 0.03

SSW-AAF-0007

0.3 1 4 23 4 2 0.4 0.03

SSW-AAF-0009

0.5 2 5 16 2 2 0.6 0.03

SSW-SAN-0002

0.3 1 5 23 4 4 0.5 0.03

SSW-SAN-0006

0.3 1 3 23 1 5 0.4 0.04

SSW-VTM-0001

0.1 1 2 29 2 4 0.4 0.04

SSW-VTM-0030

0.7 1 5 23 2 3.5 0.6 0.03

SWH-GJG-0008

3 4 5 4 0

SWH-GJG-0009

3 0 10 8 0

SWH-GJG-0012

0 0.6 16 7 0

SWH-GJG-0015

7 0 27 14

Table B6: Chemical analyses in weight percent for samples tested for slake durability and point load.

Sample SiO2

TiO2

Al2O3

Fe2O3T

MnO

MgO CaO Na2

O K2O

P2O5 S SO

4 C LOI Total

GHN-EHP-0001

67.14 0.47 13.71 3.62 0.11 1.23 0.81 2.22 3.9

7 0.19 0.6

0.03

0.08 4.55 98.7

GHN-EHP-0002

74.45 0.25 12.27 2.046 0.06

1 0.62 0.32 0.79 4.46

0.071

0.1 0.3 0.0

8 3.24 99.04

GHN-EHP-0003

65.03

0.443 12.61 4.74 0.04

1 0.78 0.33 1.26 3.97

0.117

0.6 0.3 0.0

8 7.88 98.15

GHN-EHP-0004

63.29

0.555 13.58 3.41 0.37 1.04 0.76 0.95 3.5

5 0.27

7 9.9

GHN-EHP-0007

58.15

0.624 17.43 6.237 0.16

6 2.31 0.77 1.3 3.68

0.271 7.13

 

154

Sample SiO2

TiO2

Al2O3

Fe2O3T

MnO

MgO CaO Na2

O K2O

P2O5 S SO

4 C LOI Total

GHN-HRS-0096

65.77 0.64 14.87 2.827 0.03

3 0.81 0.09 3.18 3.84

0.111 0 0.9

9 0.08 5.43 98.7

GHN-JRM-0001

61.64 0.53 13.65 5.24 0.08 1.28 0.98 1.87 3.9

1 0.19 2 1.12

0.07 8.81 101.3

8

GHN-JRM-0037

75.72 0.15 11.6 1.93 0.02

8 0.25 0.252

1.726

5.68 0.03 0.

2 0.24

0.05 2.48 100.3

4

GHN-JRM-0038 68.8 0.42 13.43 4.573 0.05

6 0.72 0.108

0.398 4.2 0.16

5 1.1

0.54

0.06 5.63 100.2

2

GHN-JRM-0039

66.64 0.6 15.1 2.58 0.02 0.5 0.08 0.15 3.6

5 0.23 0.4

0.58

0.08 6.28 96.92

GHN-JRM-0040

70.26 0.5 14.75 3.212 0.01

1 0.37 0.08 0.1 3.69 0.19 2.

1 0.47

0.05 5.85 101.6

1

GHN-JRM-0047

66.84 0.55 14.69 4.706 0.07

8 0.99 0.52 0.86 3.77 0.25 0.

7 0.52

0.07 5.99 100.5

1

GHN-KMD-0013

63.68 0.6 14.59 6.23 0.07 1.46 1.17 2.42 3.6

8 0.23 0.1

0.23

0.05 4.81 99.28

GHN-KMD-0014

61.05 0.82 14.79 5.1 0.22 2.74 3.12 3.31 4.6

5 0.29 0 0.01

0.17 2.34 98.62

GHN-KMD-0015

63.83 0.7 14.36 5.72 0.37 2.05 1.38 2.49 4.0

7 0.25 0.1

0.17

0.16 3.7 99.3

GHN-KMD-0016

61.88 0.79 14.44 5.51 0.31 2.83 2.97 3.36 3.1

2 0.29 3.42

GHN-KMD-0017

61.34 0.61 14.37 6.03 0.08 1.51 1.15 2.5 3.4

9 0.23 1.7

1.22

0.03 7.4 101.6

4

GHN-KMD-0018

70.45 0.36 12.95 3.48 0.22 1.23 0.81 1.29 4.8

1 0.08 0 4.2

GHN-KMD-0019

61.78 0.81 14.94 5.35 0.32 3.14 3.59 3.48 2.9

2 0.26 0 0.05

0.24 4.3 101.2

2

GHN-KMD-0026

69.83 0.32 12.81 3.86 0.15 0.76 0.5 2.59 4.2

6 0.13 0 0.12

0.05 3.53 98.94

GHN-KMD-0027

68.03 0.43 12.93 4.57 0.21 1.05 0.56 2.03 4.1

5 0.19 0 0.18

0.07 4.48 98.89

GHN-KMD-0028

62.36

0.574 14.28 4.796 0.26

9 1.82 1.56 2.51 3.64

0.251 5.49

GHN-KMD-0048

63.11 0.75 14.72 5.55 0.45 2.64 2.79 3.57 3.2

8 0.34 0.13 3.43

GHN-KMD-0050 62.5 0.74 14.74 5.423 0.43 2.74 2.78 3.29 3.3

3 0.34 0.1 3.84

GHN-KMD-0051

67.83 0.59 14.44 4.32 0.29 1.8 1.94 3.22 3.9

6 0.16 2.72

GHN-KMD- 61.8 0.6 14.16 5.34 0.37 2.23 2.32 2.48 3.4 0.27 1 0.0 0.2 4.49 98.88

 

155

Sample SiO2

TiO2

Al2O3

Fe2O3T

MnO

MgO CaO Na2

O K2O

P2O5 S SO

4 C LOI Total

0052 2 4 9 9

GHN-KMD-0053

70.62 0.33 12.82 3.73 0.3 0.91 0.53 1.78 4.5

4 0.06 0.1 0.2 0.0

7 3.65 99.6

GHN-KMD-0054

62.74 0.73 14.19 5.21 0.24 2.33 2.19 2.7 3.6

4 0.32 0.3

0.23

0.05 4.2 99.02

GHN-KMD-0055

71.86 0.27 12.19 3.49 0.06 0.63 0.76 0.38 3.8

8 0.1 2 0.46

0.06 5.04 101.1

5

GHN-KMD-0056

68.34 0.59 14.53 4.31 0.22 1.64 1.21 3.21 3.8 0.16 0.

1 0.08

0.04 3.09 101.3

2

GHN-KMD-0057

62.67 0.71 14.99 5.192 0.34

9 2.62 2.56 3.05 3.52

0.326

0.1

0.01

0.13 3.38 99.6

GHN-KMD-0062

67.01 0.49 13.66 5.27 0.44

2 1.35 0.51 1.8 4.18 0.2 0 0.2

4 0.12 4.72 100.0

1

GHN-KMD-0063

64.27 0.62 13.64 5.91 0.16

6 1.89 1.25 2 3.79 0.22 0.

6 0.75

0.04 5.97 101.0

7

GHN-KMD-0064 68.4 0.42 13.51 4.54 0.22 0.95 0.66 2.68 4.0

6 0.17

8 0 3.58

GHN-KMD-0065

66.82 0.66 14.69 6.12 0.52 2.15 1.29 2.76 3.7

3 0.2 0.1

0.06

0.03 3.59 102.6

7

GHN-KMD-0071

67.81 0.49 14.77 3.85 0.13 1.35 1.28 3.1 3.7

5 0.13 0.4

0.19

0.04 3.35 100.6

6

GHN-KMD-0072

63.63 0.65 14.26 5.25 0.4 2.25 2.1 3.09 3.5

7 0.29 0.1

0.01 0.1 3.6 99.25

GHN-KMD-0073

62.63 0.72 14.38 5.14 0.34 2.65 2.28 3.33 3.3

7 0.26 0.1 0.1 0.1

4 3.17 98.65

GHN-KMD-0074

65.16 0.71 14.68 5.7 0.33 2.26 1.66 2.86 3.5

3 0.22 0.1

0.08

0.04 3.23 100.5

7

GHN-KMD-0077

68.84 0.37 13.93 4.004 0.11

4 0.85 0.84 3.02 3.96

0.165

0.1

0.12

0.04 3.4 99.7

GHN-KMD-0078 70 0.43 13.14 3.597 0.11

3 1.08 0.38 2.92 3.93

0.173

0.2 0.2 0.0

4 3.31 99.53

GHN-KMD-0079

67.58 0.55 14.22 4.56 0.23 1.49 1.26 2.8 3.8

2 0.16 0.2

0.17

0.05 3.21 100.2

5

GHN-KMD-0080

64.18 0.68 14.57 5.193 0.37

5 2.37 2.35 3.36 3.4 0.309

0.1 0.1 0.0

8 3.09 100.16

GHN-KMD-0081 66.8 0.43 14.17 3.82 0.13 1.32 1.11 2.79 3.8

7 0.19 0.3

0.14

0.05 3.16 98.3

GHN-KMD-0082 60.3 0.74 14.32 5.31 0.64 2.74 2.74 3.46 3.0

5 0.34 0 0.25

0.12 4.6 98.64

GHN-KMD-0088

64.35 0.49 14.19 4.19 0.16 1.51 1.13 2.92 3.8 0.21 0.

6 0.41

0.04 5.14 99.09

 

156

Sample SiO2

TiO2

Al2O3

Fe2O3T

MnO

MgO CaO Na2

O K2O

P2O5 S SO

4 C LOI Total

GHN-KMD-0092

63.51 0.49 14.93 4.268 0.22

3 1.69 1.45 2.63 3.7 0.226

0.4

0.47

0.04 5.43 99.5

GHN-KMD-0095 75.4 0.16 11.65 1.727 0.02

5 0.39 0.14 0.47 4.81

0.032

0.2

0.28

0.04 3.51 98.81

GHN-KMD-0096

72.29 0.23 11.91 2.31 0.03

7 0.63 0.66 0.77 4.57

0.046

0.2

0.66

0.06 4.84 99.17

GHN-KMD-0097 67.2 0.37 12.99 3.245 0.12 1 0.98 0.92 5.1

4 0.14

7 0.8

0.77

0.06 6.03 99.76

GHN-KMD-0100

67.74 0.48 13.19 4.708 0.31

1 1.47 0.93 2.05 4.15

0.211 0 0.2 0.0

6 3.91 99.42

GHN-LFG-0018

69.22 0.36 13.7 4.313 0.10

2 0.78 0.397

2.335

4.35

0.161 0 3.94

GHN-LFG-0020

72.49 0.28 12.49 4.044 0.14

3 0.69 0.598

2.619

4.53

0.125 0 2.25

GHN-LFG-0037

61.32 0.5 13.88 5.1 0.29 1.87 1.39 2.05 3.5

7 0.24 0 5.5

GHN-LFG-0041

75.45 0.16 12.02 2.42 0.09

1 0.24 0.212

2.579

4.92

0.044 0 1.92

GHN-LFG-0060

64.64

0.583 13.49 4.664 0.10

9 1.57 1.17 2.64 3.44

0.213 5.12

GHN-LFG-0085

62.66 0.69 14.68 6.13 0.28 2.48 2.08 2.62 3.5

6 0.24 0 0.24

0.04 4.94 100.6

8

GHN-LFG-0086 60.4 0.67 14.25 6.09 0.3 2.37 2.03 2.53 3.4

6 0.31 5.32

GHN-LFG-0088

61.25 0.77 14.44 5.04 0.3 2.77 2.96 3.31 3.4

1 0.27 0.1

0.05

0.23 6.03 100.8

8

GHN-LFG-0089

70.71

0.307 13.21 3.09 0.05

4 0.52 0.6 3.07 4.3 0.121 2.39

GHN-LFG-0090

60.36 0.77 14.7 6.52 0.46 2.55 2.3 3.32 3.3

7 0.29 0.6

0.31

0.13 4.13 99.78

GHN-LFG-0091

62.44 0.59 14.64 4.66 0.05

1 1.52 0.78 2.94 3.65

0.179

1.5

0.96

0.05 6.87 100.8

GHN-RDL-0002 71 0.63 14.27 1.3 0.02 0.64 0.09 0.11 4.2

4 0.07 0 0.19

0.31 4.29 97.17

GHN-RDL-0003

71.84 0.64 15.09 0.67 0.02 0.76 0.06 0.04 4.4

1 0.03 0 3.14

GHN-SAW-0003

80.93 0.15 11.21 0.645 0.01

8 0.31 0.032

0.056

3.56

0.029

0.1

0.09

0.04 2.21 99.41

GHN-SAW-0004

62.63 0.57 14.32 5.437 0.05

2 1.25 0.721

2.678

3.65

0.133

0.3

1.03

0.07 7.04 99.87

GHN-SAW- 75.3 0.17 11.85 2.945 0.04 0.34 0.08 1.41 5.0 0.04 0 0.1 0.0 2.69 100.2

 

157

Sample SiO2

TiO2

Al2O3

Fe2O3T

MnO

MgO CaO Na2

O K2O

P2O5 S SO

4 C LOI Total

0005 4 6 7 7 6 6 6 3

GHN-SAW-0200

61.04 0.58 14.78 5.201 0.20

4 1.71 1.212

0.793 3.6 0.21

9 0.1

0.26

0.51 6.02 96.23

GHN-SAW-0201 69.8 0.26 12.26

6 4.303 0.058 0.77 0.41

7 1.07

7 4.22

0.286

0.1

0.49

0.15 5.46 99.64

GHN-VTM-0263

71.17

0.338 13.01 4.345 0.07

2 0.86 0.67 0.5 3.93

0.169

2.4

0.37

0.06 5.07 102.9

5

GHN-VTM-0293

69.66

0.359 13.27 4.279 0.12

5 0.99 1.35 0.86 3.86

0.144

1.9 0.6 0.1

1 5.53 103.08

GHN-VTM-0450

63.45 0.77 14.62 6.38 0.36 2.6 1.68 3.27 3.3 0.25 0.

1 0.11

0.06 3.19 100.1

GHN-VTM-0453 59.8 0.71 14.49 6.18 0.46 2.57 2.26 2.61 3.5

3 0.29 1.3

0.47

0.14 5.13 99.95

GHN-VTM-0508

55.32 0.59 15.18 5.61 0.07 1.62 2.32 2.51 3 0.25 0.

1 1.86

0.13 9.81 98.32

GHN-VTM-0554

49.69 0.54 14.31 4.4 0.21

7 1.93 6.58 0.07 3.44

0.221 0.0

1 9.21

GHN-VTM-0598

76.44 0.23 12.4 1.94 0.05 0.53 0.21 0.16 3.7

3 0.04 0.01 4.19

GHN-VTM-0599

59.87 0.56 15.65 4.873 0.18

6 2.1 2.25 0.74 3.74

0.219

0.2

0.04

0.53 6.08 97.03

GHN-VTM-0603

61.31 0.68 15.99 5.33 0.1 1.75 0.77 0.93 3.6

4 0.15 0 0.63

0.89 8.37 100.5

5

GHN-VTM-0606

71.25 0.35 12.09 3.63 0.06 0.67 0.31 1.09 4.2

7 0.16 0 0.33

0.13 5.32 99.69

GHN-VTM-0607

68.88 0.5 14.32 4.05 0.16 1.21 0.57 1.45 3.8

1 0.14 0.2

0.39

0.07 5.25 101.0

3

GHN-VTM-0614

63.72 0.71 18.09 4.14 0.05 1.23 4.11 0.21 5.3

6 0.06 0 2.53

0.23 9.28 109.7

2

GHR-VWL-0004

58.53 0.68 16.41 8.4 0.11 1.84 0.37 0.4 4.1

6 0.17 0 9.15

HAS-GJG-0006

49.79

1.002 13.46 8.052 0.12

5 5.68 3.11 0.63 4.02

0.568

2.6 1.7 0.0

3 11.3

5 102.0

7

HAS-GJG-0007

46.86 0.84 12.39 9.339 0.08

4 4.7 4.19 0.74 2.44 0.66 3.

3 2.68

0.02

15.63 103.9

HAS-GJG-0008

47.31

0.938 12.43 7.975 0.12

4 5.29 4.39 0.45 2.54

0.439

0.3

2.98

0.05

13.58 98.75

HAS-GJG-0009

59.18

1.048 21.37 1.232 0.00

9 0.61 1.07 0.11 5.96

0.166

0.2

0.97

0.01 6.33 98.23

HAS-GJG-0010

66.89

0.778 14.32 2.002 0.04

9 2.29 1.11 0.07 4.04

0.161

0.1

0.89

0.02 6.27 98.98

 

158

Sample SiO2

TiO2

Al2O3

Fe2O3T

MnO

MgO CaO Na2

O K2O

P2O5 S SO

4 C LOI Total

MID-AAF-0001

61.97

0.513

13.722 5.148 0.05

2 1.27 1.67 2.04 4.09

0.197

0.5

1.24

0.03 7.2 99.62

MID-AAF-0002

63.01

0.517 13.67 5.005 0.03

9 1.14 1.61 1.34 4.19

0.153

0.4

1.29

0.04 7.6 99.98

MID-VTM-0002

73.35 0.14 11.05 2.62 0.05 0.43 0.57 0.31 4.8

2 0.04 1 0.53

0.02 3.98 98.92

MIN-AAF-0001

73.34

0.391 12.82 3.014 0.02

1 0.66 0.1 0.39 4.29

0.114 0 0.3

8 0.23 4.27 100.0

2

MIN-AAF-0004

71.85

0.376 13.14 3.19 0.01

8 0.62 0.09 0.45 4.39 0.12 0 0.4

3 0.26 4.71 99.65

MIN-AAF-0010 70.2 0.49

9 13.68 2.948 0.02 0.67 0.06 0.42 4.51

0.098

0.1

0.62

0.39 4.58 98.76

MIN-AAF-0012

70.76

0.364 12.4 3.751 0.02 0.63 0.04 0.4 3.9

9 0.13

7 0 0.6 0.21 5.2 98.51

MIN-AAF-0013

74.83 0.33 12.12 1.74 0.02 0.5 0.04 0.53 4.2

8 0.07 0 0.23

0.07 3.2 97.97

MIN-AAF-0015

74.47

0.407 12.36 1.782 0.01

8 0.59 0.04 0.56 4.3 0.066 0 0.2

2 0.04 3.07 97.95

MIN-GFA-0001

72.65

0.502 13.17 2.442 0.22 0.79 0.1 0.62 4.3

1 0.10

2 0.1

0.21

0.02 3.46 98.65

MIN-GFA-0003

70.88 0.46 12.98 3.586 0.39 1.23 0.71 1.07 3.5

3 0.17

9 0.1

0.07

0.03 2.91 98.11

MIN-GFA-0005 73.7 0.39

2 13.2 2.112 0.022 0.68 0.02 0.46 4.1

9 0.09

2 0.1

0.25

0.01 3.68 98.86

MIN-GFA-0009 74.7 0.39

7 12.5 2.585 0.02 0.6 0.06 0.57 4.03

0.129 0 0.2

3 0.03 3.42 99.3

MIN-SAN-0002

71.07 0.45 12.74 2.96 0.02 0.64 0.1 0.69 4.2

3 0.12 0 0.54 0.3 4.68 98.54

MIN-VTM-0003

67.02 0.47 14.55 3.091 0.04

3 1.01 1.4 2.51 4.91

0.164 0 0.2

1 0.04 4.3 99.75

MIN-VTM-0004

65.16

0.542 13.29 4.026 0.07

9 1.48 1.45 1.79 4.1 0.221

0.1

0.69

0.14 5.13 98.22

MIN-VTM-0006

67.04

0.509 12.72 3.146 0.02

9 1.18 1.81 1.5 4.12

0.183 0 1.0

3 0.05 5.64 98.98

MIN-VTM-0007

66.84

0.565 13.5 4.389 0.03

9 1.42 0.72 1.55 4.12

0.234 0 0.4

2 0.08 4.99 98.88

MIN-VTM-0008

68.01

0.535 13.43 3.718 0.06

5 1.35 0.61 1.87 4.24

0.203

0.1

0.19

0.44 4.43 99.16

MIN-VTM-0009

65.27

0.536 13.14 4.455 0.05 1.44 1.36 1.62 4.0

2 0.21

9 0 0.77

0.04 5.93 98.86

PIT-LFG- 64.3 0.57 13.89 4.126 0.04 1.19 0.44 1.90 3.8 0.10 0. 1.2 0.0 8.29 100.5

 

159

Sample SiO2

TiO2

Al2O3

Fe2O3T

MnO

MgO CaO Na2

O K2O

P2O5 S SO

4 C LOI Total

0013 7 9 5 2 5 3 5 5

PIT-RDL-0002

78.11 0.15 11.39 1.188 0.01

7 0.29 0.06 0.39 5.86

0.024

0.1 0 1.81

PIT-VCV-0001

62.64

0.686 15.49 5.346 0.13

4 0.9 1.02 2.62 4.75

0.337

4.4

0.05

0.15 4.91 103.4

6

PIT-VCV-0002

68.37

0.352 13.16 4.235 0.12

3 0.75 1.32 0.9 5.3 0.134

3.1

0.05

0.29 4.05 102.1

6

PIT-VCV-0003

61.44

0.708 16.07 5.83 0.09

7 1.34 0.81 3.42 3.92

0.342

4.5

0.06

0.07 5.09 103.6

6

PIT-VCV-0004 81.8 0.13

5 10.45 0.803 0.029 0.33 0 0.07 3.4

6 0.02

3 0 0.01

0.02 1.99 99.14

PIT-VCV-0005

79.67

0.133 10.62 1.463 0.03

4 0.36 0 0.07 3.48

0.021 0 0.2

3 0.02 4.77 100.8

9

PIT-VCV-0006 0 0.1

3 0.05

PIT-VCV-0007 66 0.56 14.88 4.301 0.05

7 0.85 1.04 1.28 5.61 0.19 2.

4 0.06

0.16 4.21 101.5

7

PIT-VCV-0008

68.84

0.443 12.56 3.806 0.14 0.79 2.29 0.38 4.4

5 0.16

2 2.2

0.04

0.67 4.76 101.4

9

PIT-VCV-0009

63.49

0.591 14.29 6.138 0.15

3 1.3 1.37 1.75 4.11

0.225

3.3

0.06

0.26 4.9 101.9

4

PIT-VCV-0010

66.98

0.467 14.45 2.277 0.03

2 1.16 1.12 2.4 6.16

0.187

1.6

0.05

0.23 3.46 100.5

2

PIT-VCV-0011

66.49 0.49 14.21 2.695 0.08

3 1.29 1.52 2.12 5.24

0.179

1.9

0.05 0.3 4.38 100.9

3

PIT-VCV-0012

71.65

0.324 12.45 3.267 0.17

4 0.64 1.14 0.2 5.19

0.107

1.5

0.03

0.36 3.79 100.8

5

PIT-VCV-0013

73.97

0.278 11.81 2.2 0.12

3 0.55 1.57 0.08 4.05

0.083

1.1

0.04

0.37 3.47 99.65

PIT-VCV-0014 73.3 0.3 12.35 2.398 0.13

3 0.58 0.96 0.12 4.73

0.088

1.1

0.04

0.29 3.22 99.59

PIT-VCV-0015

76.04

0.157 11.49 0.539 0.00

7 0.19 0.34 1.91 6.45

0.031

0.3

0.02

0.06 1.09 98.66

PIT-VCV-0016

67.83

0.726 14.1 1.155 0.04

4 1.22 1.44 1.79 6.98

0.247

0.1

0.03

0.24 2.47 98.4

PIT-VCV-0017

70.05 0.47 13.96 0.408 0.02

4 0.71 0.88 0.99 7.25

0.159

0.5

0.04

0.14 2.48 98.02

PIT-VCV-0018

71.07 0.33 12.52 0.649 0.02

2 0.57 1.04 1.41 6.78

0.116

0.5

0.02

0.22 2.24 97.52

PIT-VCV-0019

61.11

0.709 18.55 3.08 0.02

5 0.17 2.65 0.31 3.68

0.279

0.6 1.4 0.0

3 7.03 99.57

 

160

Sample SiO2

TiO2

Al2O3

Fe2O3T

MnO

MgO CaO Na2

O K2O

P2O5 S SO

4 C LOI Total

PIT-VCV-0020

60.32 0.75 18.5 4.356 0.04

7 0.33 1.89 0.49 5.26

0.296

1.4 0.1 0.0

5 5.55 99.38

PIT-VCV-0021

52.11

0.858 13.48 5.874 0.10

1 4.16 4.63 2.18 3.9 0.375 2 2.2

8 0.05 8.36 100.3

1

PIT-VCV-0022

54.33 0.86 12.5 7.65 0.07

5 3 4.19 3.28 2.77

0.399

4.7

1.85

0.05 8.95 104.5

6

PIT-VCV-0023

51.62

0.838 11.98 8.734 0.04

8 1.46 4.51 2.33 3.06

0.421

6.3

2.04

0.06

10.83

104.26

PIT-VCV-0024

61.86 0.66 15.36 1.529 0.08

6 0.73 5.22 0.21 5.39

0.534 1 0.1

3 0.1 3.81 96.63

PIT-VCV-0025

68.14

0.509 13.49 4.73 0.07

8 1.08 0.68 0.18 4.94

0.199

3.4

0.19

0.12 4.86 102.5

8

PIT-VCV-0026

65.79

0.532 13.6 5.599 0.03

3 1.24 0.49 0.27 5 0.173

4.1

0.18

0.05 5.53 102.5

5

PIT-VCV-0027

64.85

0.548 15.73 4.51 0.01

9 1.37 0.72 1.6 4.99

0.242

2.7

0.05 0.1 4.3 101.7

PIT-VCV-0028

75.21

0.172 12.04 0.539 0.01

5 0.15 0.5 2.81 5.91

0.032

0.2

0.04

0.12 0.91 98.68

PIT-VCV-0029

63.58

0.544 15.8 4.081 0.03

9 1.54 1.37 1.67 5.6 0.24 2.4

0.06

0.25 4.32 101.5

3

PIT-VCV-0030

64.81

0.539 15.51 3.784 0.02

5 1.5 1.15 1.34 5.02

0.246

2.5

0.04 0.2 4.99 101.6

3

PIT-VTM-0001

65.63

0.738 15.41 5.005 0.18

5 2.13 1.02 3.67 1.92

0.218 3.33

PIT-VTM-0002

62.18

0.554 14.84 5.984 0.13

9 2.36 2.57 3.63 3.55

0.248 2.73

QPS-AAF-0001

66.22 0.6 14.16 3.88 0.05 1.23 0.88

5 1.85 3.61 0.2 0.

1 0.55

0.09 5.27 98.7

QPS-AAF-0003

63.06

0.592 14.53 4.796 0.05

4 1.57 1.25 1.88 3.71

0.241

0.1

0.91

0.03 6.74 99.42

QPS-AAF-0005

61.85

0.599 14.31 4.84 0.04

9 1.54 1.44 1.82 3.65 0.23 0 1.1

7 0.03 8.03 99.58

QPS-AAF-0009

63.95

0.692 14.47 4.334 0.02

8 1.02 1.61 1.21 3.65

0.263

0.2

1.18

0.03 6.93 99.55

QPS-AAF-0020

62.88

0.637 14.42 5.357 0.03

5 1.27 1.04 1.55 3.75 0.31 0 1.0

2 0.05 7.16 99.49

QPS-AAF-0022

64.34

0.626 14.57 4.785 0.03

4 1.34 0.74 1.56 3.59

0.254

0.1

0.75

0.08 6.08 98.8

QPS-SAN-0002

67.69 0.5 13.66 3.36 0.02 0.93 0.68 1.24 3.7

1 0.17 0 0.97

0.04 5.13 98.1

QPS-VTM- 63.6 0.61 14.26 4.58 0.04 1.4 1 1.85 3.6 0.24 0. 0.7 0.0 6.27 98.4

 

161

Sample SiO2

TiO2

Al2O3

Fe2O3T

MnO

MgO CaO Na2

O K2O

P2O5 S SO

4 C LOI Total

0001 2 1 5 5

ROC-KMD-0001

61.14 0.7 13.61 5.27 0.13 3.11 2.86 2.84 3.2

3 0.35 0.1

0.01

1.74 6.81 101.8

5

ROC-KMD-0002 60.4 0.73 14.18 5.654 0.09 3.44 5.26 3.5 4.1 0.35 0 0.0

1 0.06 1.38 99.17

ROC-VTM-0032

58.69 0.66 16.11 5.99 0.1 1.3 3.12 2.41 3.0

1 0.16 0 0 0 6.49 98.04

SCS-LFG-0004

61.48

0.525

15.445 2.235 0.06 2.71 1.89 0.81

5 2.6 0.13 0.3

1.35

0.07 7.82 97.38

SCS-LFG-0005

64.97 0.61 15.86 2.81 0.07 2.58 1.53 0.85 4.1

1 0.14 0.9

1.13

0.04 5.59 101.2

2

SCS-LFG-0006

67.07 0.55 15.6 1.97 0.05 2.19 0.76 3.03 3.8

1 0.19 0.3

0.46

0.05 4.59 100.5

9

SCS-LFG-0007

65.27 0.51 15.13 3.2 0.06 2.06 0.49 3.81 3.7

9 0.24 1.7

0.12

0.05 4.29 100.7

3

SCS-LFG-0008

64.75 0.46 13.28 9 0.01 0.46 0.25 0.15 3.9

2 0.19 7.4

0.36

0.05 7.44 107.6

8

SPR-AAF-0001 62 0.78 14.42 5.5 0.11 3.69 2.18 3.38 2.7

7 0.33 0.3

0.12

0.04 2.96 98.57

SPR-AAF-0003

60.25 0.79 14.42 5.82 0.13 3.31 1.86 3.2 3.0

4 0.35 0.3

0.27

0.05 4.24 98.02

SPR-SAN-0002

59.74 0.73 14.39 5.9 0.11 2.96 2.31 2.79 3.5 0.38 0.

2 0.46

0.05 4.22 97.72

SPR-VTM-0005

62.12

0.711 15.74 6.006 0.09 2.69 1.82 4.72 3.2

1 0.34

5 0.3

0.04

0.06 2.04 99.92

SPR-VTM-0008

60.54

0.752

14.517 5.887 0.1 3.87 2.59

6 3.56

5 2.81

0.322 0 0.0

3 0.21 3.37 98.6

SPR-VTM-0010 61.9 0.81

4 14.51 6.116 0.13 3.81 2.65 3.54 2.72

0.341

0.4

0.03

0.28 3.1 100.3

8

SPR-VTM-0012

80.11

0.145 11.66 0.308 0.00

9 0.23 0.02 0.14 3.48

0.035

0.2

0.11

0.03 2.64 99.07

SPR-VTM-0014

77.69 0.15 11.55 0.9 0.01 0.27 0.02 0.36 4 0.03 0.

1 0.11

0.03 2.44 97.65

SPR-VTM-0017

76.17

0.293 12.85 1.397 0.01

5 0.51 0.01 0.14 4.23

0.028

0.5

0.21

0.03 3.23 99.57

SPR-VTM-0021

76.77 0.15 11.8 1.09 0.02 0.37 0.01 0.11 4.2

9 0.03 0.1

0.11

0.01 2.71 97.6

SSS-AAF-0001

59.44 0.64 14.29 6.34 0.06 2.28 1.85 1.33 3.6

7 0.27 0.3

0.83

0.02 6.79 98.09

SSS-AAF-0004

59.56

0.576

13.678 6.596 0.05

9 2.65 2.265 1.55 2.8

6 0.27

6 0.3

1.02

0.02 7.3 98.74

 

162

Sample SiO2

TiO2

Al2O3

Fe2O3T

MnO

MgO CaO Na2

O K2O

P2O5 S SO

4 C LOI Total

SSS-AAF-0005

64.12 0.64 14.46 5.69 0.04

1 2.03 0.76 0.67 3.59 0.23 0.

2 0.78

0.03 6.4 99.63

SSS-AAF-0007 59.5 0.61

5 13.72 7.0697 0.062 2.57 1.88 1.66 3.1

1 0.29

8 0.3

0.96

0.03 7.44 99.23

SSS-AAF-0009

73.62

0.313 12.62 1.62 0.02

5 0.72 0.45 0.58 4.11

0.034

0.3

0.45

0.03 4.08 98.91

SSS-EHP-0002

68.53

0.478 12.85 3.102 0.09

5 1.56 1.88 2.17 4.65 0.19 0.

9 0.11

0.21 3.02 99.78

SSS-EHP-0003

70.14

0.374 12.7 2.981 0.67 0.71 1.42 1.74 5.3

3 0.13

8 1.3

0.15

0.19 3.14 101.0

1

SSS-EHP-0011

65.66 0.52 13.87 3.45 0.03

9 1.53 1.58 1.41 5.51

0.198

1.8

0.08

0.23 3.4 99.26

SSS-EHP-0012

61.66

0.716 14.67 4.78 0.06

9 2.63 2.19 1.67 4.66

0.341

1.9

0.14

0.29 4.04 99.73

SSS-EHP-0014

59.84

0.808

14.681 5.446 0.11

4 3.35 3.479 3.55 3 0.37

5 0.8

0.09

0.35 3.09 98.99

SSS-EHP-0015

57.44

0.799 14.01 6.597 0.10

7 4.44 3.247 3.29 3.0

5 0.42

2 1.6

0.35

0.19 4.5 100.0

4

SSS-EHP-0017

59.01

0.706

14.523 6.311 0.06 2.35 2.12 1.3 3.8

5 0.33

8 2.4

0.91

0.09 7.55 101.5

5

SSS-EHP-0019

60.77 0.69 15.16

8 6.103 0.057 1.72 1.44 1.48

8 3.92

0.287

2.9

0.61

0.05 6.61 101.8

SSS-EHP-0020

64.88

0.456

13.375 3.265 0.06

2 1.33 1.058

1.391

4.57

0.162

1.3

0.91

0.04 7.05 99.89

SSS-EHP-0023

62.29

0.525

14.415 4.655 0.11

5 1.27 1.035

0.875

3.92 0.15 0.1

8 9.95

5

SSS-EHP-0025

68.19

0.383

13.574 3.68 0.1 1.14 0.63

7 1.38 4.13

0.149

1.2

0.42

0.05 4.84 99.91

SSS-EHP-0031

71.67

0.355 12.81 3.29 0.11

5 0.95 0.56 1.3 4.21 0.11 0.

5 0.16

0.02 3.1 99.15

SSS-EHP-0032

72.04

0.336 12.37 2.662 0.10

5 0.9 0.71 1.39 4.68

0.109

0.5

0.21 0.1 3.23 99.32

SSS-EHP-0033

70.29

0.478 13.35 3.597 0.12

6 1.19 0.62 2.24 4.18

0.169

0.1

0.07

0.03 2.79 99.21

SSS-EHP-0034

70.01

0.434 13.39 3.718 0.16

7 1.2 0.53 2.26 4.26

0.169

0.2

0.08

0.04 3.04 99.45

SSS-EHP-0036

68.37

0.528 14.09 4.07 0.08

5 1.15 0.65 1.67 3.43

0.187

1.2

0.19

0.04 3.96 99.57

SSS-VEV-0001

49.48 0.79 11.43 22.759 0.01

7 0.69 0.147

1.713

3.01

0.222

0.9 0 8.47

SSS-VTM- 69.4 0.50 13.98 4.29 0.13 1.28 0.66 1.25 3.7 0.21 0. 4.17

 

163

Sample SiO2

TiO2

Al2O3

Fe2O3T

MnO

MgO CaO Na2

O K2O

P2O5 S SO

4 C LOI Total

0012 8 3 9 1

SSS-VTM-0600

67.31

0.526 14.75 4.444 0.13

2 1.25 0.82 1.5 4.1 0.225

0.1 0.1 0.0

6 4.2 99.53

SSW-AAF-0001

60.28 0.78 14.9 6.54 0.11 2.25 1.58 2.35 3.6

4 0.36 0.2 0.1 0.0

6 6.01 99.18

SSW-AAF-0002

61.99

0.577 14.08 5.456 0.09

7 1.75 1.75 1.13 3.65

0.212

0.4

0.43

0.07 7.48 99.11

SSW-AAF-0005

60.01 0.56 13.63 5.3 0.06 1.86 1.85 2.28 3.6

7 0.25 0.1

1.34

0.04 7.63 98.6

SSW-AAF-0007

64.77 0.57 13.76 4.58 0.05 1.69 1.14 1.67 3.8

3 0.24 0.8

0.61

0.04 5.37 99.11

SSW-SAN-0002

62.56 0.59 14.28 5.03 0.07 1.79 1.29 2.38 3.7

8 0.25 0.2

1.26

0.03 5.44 98.95

SSW-SAN-0006

65.71 0.47 13.16 3.7 0.06 0.93 0.87 0.9 4.0

3 0.12 0.1

1.45

0.03 6.84 98.32

SSW-VTM-0001 68.4 0.34 11.64 3.619 0.08

1 0.84 1.34 0.8 3.59

0.075

0.2

1.39

0.02 7.86 100.2

4

SSW-VTM-0016

62.24

0.679 14.9 5.995 0.10

5 2.01 1.98 2.5 3.61

0.303

0.9

0.27

0.14 4.6 100.2

1

SSW-VTM-0019

60.99

0.652 14.74 6.204 0.1 2.04 1.85 2.48 3.6

6 0.29

5 1 0.58

0.07 5.48 100.1

2

SSW-VTM-0023

61.46

0.627 14.62 6.061 0.08

6 1.86 1.88 1.91 3.69

0.276

1.4

0.55

0.08 5.87 100.3

3

SSW-VTM-0028

62.79

0.638 14.46 5.852 0.01 2.2 1.33 1.67 3.6

3 0.26

8 0.5

0.66

0.03 5.58 99.59

SSW-VTM-0030

62.14

0.628 14.47 5.467 0.08

7 1.78 2.09 1.88 3.66

0.263

0.6

0.71

0.07 5.8 99.68

SWH-GJG-0008

62.52

0.402 12.69 3.883 0.03

5 1.02 2.32 2.72 4.36

0.213

0.3

1.49

0.03 7.64 99.64

SWH-GJG-0009

49.71

0.423 11.99 10.494 0.08

5 1.79 2.73 2.23 2.82

0.671

0.6

2.59

0.05

13.98

100.15

SWH-GJG-0012

66.11

0.567 15.49 1.375 0.03

6 1.61 1.13 2.94 2.96

0.048

0.4

0.75

0.02 5.47 98.91

SWH-GJG-0015

53.13

0.492 13.12 5.203 0.06

4 2.35 4.26 1.26 2.35

0.394

0.1

3.41

0.02 13.9 100.0

3

 

164

Table B7: Summary statistics of the point load strength for GHN rock-pile samples. Geologic conceptual model is in Figure 1.3.

Location Statistics Point Load Strength Index

Unit I

No. of Samples 2 Mean (MPa) 1.1 Standard Deviation (MPa) NA Minimum (MPa) 0.6 Maximum (MPa) 1.6 Coefficient of Variation (%) NA

Unit J

No. of Samples 6 Mean (MPa) 5.0 Standard Deviation (MPa) 1.7 Minimum (MPa) 3.3 Maximum (MPa) 7.0 Coefficient of Variation (%) 34.0

Unit N

No. of Samples 4 Mean (MPa) 2.6 Standard Deviation (MPa) 1.4 Minimum (MPa) 1.1 Maximum (MPa) 4.5 Coefficient of Variation (%) 53.8

Unit K

No. of Samples 4 Mean (MPa) 5.3 Standard Deviation (MPa) 2.0 Minimum (MPa) 3.7 Maximum (MPa) 8.2 Coefficient of Variation (%) 37.7

Unit O

No. of Samples 4 Mean (MPa) 3.5 Standard Deviation (MPa) 1.3 Minimum (MPa) 2.4 Maximum (MPa) 5.4 Coefficient of Variation (%) 37.1

Unit R

No. of Samples 2 Mean (MPa) 5.8 Standard Deviation (MPa) NA Minimum (MPa) 4.3 Maximum (MPa) 7.3 Coefficient of Variation (%) NA

Unit S

No. of Samples 3 Mean (MPa) 4.0 Standard Deviation (MPa) 1.0 Minimum (MPa) 3.4 Maximum (MPa) 5.3

 

165

Location Statistics Point Load Strength Index

Coefficient of Variation (%) 25.0

Unit U

No. of Samples 1 Mean (MPa) 6.1 Standard Deviation (MPa) NA Minimum (MPa) 6.1 Maximum (MPa) 6.1 Coefficient of Variation (%) NA

Unit UV

No. of Samples 2 Mean (MPa) 5.3 Standard Deviation (MPa) NA Minimum (MPa) 4.5 Maximum (MPa) 6.1 Coefficient of Variation (%) NA

Unit M

No. of Samples 1 Mean (MPa) 3.7 Standard Deviation (MPa) NA Minimum (MPa) 3.7 Maximum (MPa) 3.7 Coefficient of Variation (%) NA

Rubble

No. of Samples 1 Mean (MPa) 6.5 Standard Deviation (MPa) NA Minimum (MPa) 6.5 Maximum (MPa) 6.5 Coefficient of Variation (%) NA

Table B8: Summary statistics of the slake durability indices for GHN rock pile samples. Geologic conceptual model is in Figure 1.3.

Units Statistics Slake Durability Index

Traffic

No. of Samples 2 Mean (%) 97.0 Standard Deviation (%) NA Minimum (%) 96.0 Maximum (%) 98.0 Coefficient of Variation (%) NA

Unit C

No. of Samples 1 Mean (%) 97.9 Standard Deviation (%) NA Minimum (%) 97.9 Maximum (%) 97.9 Coefficient of Variation (%) NA

Unit I No. of Samples 4 Mean (%) 87.9

 

166

Units Statistics Slake Durability Index

Standard Deviation (%) 5.5 Minimum (%) 82.2 Maximum (%) 95.0 Coefficient of Variation (%) 6.3

Unit J

No. of Samples 7 Mean (%) 95.8 Standard Deviation (%) 1.9 Minimum (%) 94.0 Maximum (%) 98.5 Coefficient of Variation (%) 2.0

Unit N

No. of Samples 5 Mean (%) 96.3 Standard Deviation (%) 1.4 Minimum (%) 94.0 Maximum (%) 98.5 Coefficient of Variation (%) 1.5

Unit K

No. of Samples 5 Mean (%) 96.2 Standard Deviation (%) 2.2 Minimum (%) 93.6 Maximum (%) 98.4 Coefficient of Variation (%) 2.3

Unit O

No. of Samples 18 Mean (%) 96.5 Standard Deviation (%) 1.4 Minimum (%) 93.6 Maximum (%) 98.1 Coefficient of Variation (%) 1.5

Unit R

No. of Samples 2 Mean (%) 96.4 Standard Deviation (%) NA Minimum (%) 95.5 Maximum (%) 97.3 Coefficient of Variation (%) NA

unit S

No. of Samples 3 Mean (%) 97.4 Standard Deviation (%) 1.6 Minimum (%) 95.6 Maximum (%) 98.4 Coefficient of Variation (%) 1.6

Unit U No. of Samples 5 Mean (%) 97.7 Standard Deviation (%) 0.6

 

167

Units Statistics Slake Durability Index

Minimum (%) 97.1 Maximum (%) 98.5 Coefficient of Variation (%) 0.6

Unit UV

No. of Samples 3 Mean (%) 96.7 Standard Deviation (%) 0.8 Minimum (%) 95.9 Maximum (%) 97.4 Coefficient of Variation (%) 0.8

Unit M

No. of Samples 1 Mean (%) 96.6 Standard Deviation (%) NA Minimum (%) 96.6 Maximum (%) 96.6 Coefficient of Variation (%) NA

Rubble

No. of Samples 7 Mean (%) 97.4 Standard Deviation (%) 1.1 Minimum (%) 95.2 Maximum (%) 98.5 Coefficient of Variation (%) 1.1

Colluvium

No. of Samples 9.0 Mean (%) 95.7 Standard Deviation (%) 1.7 Minimum (%) 93.0 Maximum (%) 98.5 Coefficient of Variation (%) 1.8

Unstable GHN

No. of Samples 11 Mean (%) 95.7 Standard Deviation (%) 5.1 Minimum (%) 80.9 Maximum (%) 99.2 Coefficient of Variation (%) 5.3

 

168

Table B9: Summary statistics of the point load strength for all rock pile samples. Location of Questa rock piles is in Figure 1.2.

Rock Pile Location Statistics Point Load Strength Index

Goat Hill North (GHN)

No. of Samples 31 Mean(MPa) 4.3 Standard Deviation (MPa) 1.9 Minimum (MPa) 0.6 Maximum (MPa) 8.2 Coefficient of Variation (%) 43.4

Spring Gulch (SPR)

No. of Samples 7 Mean(MPa) 3.0 Standard deviation (MPa) 1.2 Minimum (MPa) 1.3 Maximum (MPa) 4.8 Coefficient of Variation (%) 38.8

Sugar Shack South (SSS)

No. of Samples 8 Mean(MPa) 2.2 Standard Deviation (MPa) 0.8 Minimum (MPa) 1.0 Maximum (MPa) 3.8 Coefficient of Variation (%) 35.9

Sugar Shack West (SSW)

No. of Samples 11 Mean(MPa) 4.2 Standard Deviation (MPa) 1.3 Minimum (MPa) 2.0 Maximum (MPa) 6.1 Coefficient of Variation (%) 31.0

Middle (MID)

No. of Samples 2 Mean(MPa) 4.5 Standard Deviation (MPa) NA Minimum (MPa) 4.4 Maximum (MPa) 4.5 Coefficient of Variation (%) NA

Table B10: Summary statistics of the slake durability indices for all rock pile samples. The locations of the Questa rock piles are in Figure 1.2.

Location Statistics Slake Durability Index

GHN

Number of Samples 76 Mean (%) 96.1 Standard Deviation (%) 3.2 Minimum (%) 80.9 Maximum (%) 99.2 Coefficient of Variation (%) 3.4

SPR Number of Samples 8 Mean (%) 96.1

 

169

Location Statistics Slake Durability Index Standard Deviation (%) 5.2 Minimum (%) 83.5 Maximum (%) 99.2 Coefficient of Variation (%) 5.4

SSS

Number of Samples 30 Mean (%) 97.4 Standard Deviation (%) 2.8 Minimum (%) 85.3 Maximum (%) 99.5 Coefficient of Variation (%) 2.7

SSW

Number of Samples 15 Mean (%) 96.3 Standard Deviation (%) 4.0 Minimum (%) 82.3 Maximum (%) 98.6 Coefficient of Variation (%) 4.1

MID

Number of Samples 3 Mean (%) 96.9 Standard Deviation (%) 1.1 Minimum (%) 95.6 Maximum (%) 97.6 Coefficient of Variation (%) 1.1

 

170

APPENDIX B2. METHODOLOGY IN CALCULATION OF POINT LOAD STRENGTH INDEX OF A SAMPLE The plot of P versus De

2 of rock fragments of a sample generally results in a straight line but points around this line are usually scattered for weathered irregular rock fragments. Hence ISRM, 1985 states that points that deviate from the straight line should be disregarded but should not be deleted. Figure B1 shows a plot of P versus De

2 with the entire data points whereas Figure B2 shows a plot with the removed deviated points. The average of Is50 values of these remaining points is the reported Is50 for each sample.

Figure B1: P (peak load) versus De2 for sample MIN-SAN-0001 with 14 test points with

graphical IS50 of 4.0 MPa and an average IS50 using the correction factor (equation 2) for the entire 14 tests of 4.82 MPa.

Figure B2: P (peak load) versus De2 (equivalent diameter) for sample MIN-SAN-0001

with 10 test points after eliminating the points deviating from the straight line with graphical IS50 of 5.0 MPa and an average IS50 using the correction factor (equation 2) for the 10 remaining points of 5.04 MPa. The reported Is50 for sample MIN-SAN-0001 is 5.04 MPa.

 

171

Figure B3: Correlation plot of point load strength index (MPa) vs. apatite (%) where (a)

represent samples from GHN, (b) represent samples from all other rock piles and (c)

represent samples from drill cores, colluvium and the debris flow.

(a) (b)

(c)

 

172

Figure B4: Correlation plot of slake durability index (%) vs. apatite (%) where (a) represent samples from GHN, (b) represent samples from all other rock piles and (c) represent samples from drill cores, colluvium and the debris flow.

(a) (b)

(c)

 

173

Figure B5: Correlation plot of point load strength index (MPa) vs. chlorite (%) where (a)

represent samples from GHN, (b) represent samples from all other rock piles and (c)

represent samples from drill cores, colluvium and the debris flow.

(a) (b)

(c)

 

174

Figure B6: Correlation plot of slake durability index (%) vs. chlorite (%) where (a)

represent samples from GHN, (b) represent samples from all other rock piles and (c)

represent samples from drill cores, colluvium and the debris flow.

(a) (b)

(c)

 

175

Figure B7: Correlation plot of point load strength index (MPa) vs. illite (%) where (a)

represent samples from GHN, (b) represent samples from all other rock piles and (c)

represent samples from drill cores, colluvium and the debris flow.

(a) (b)

(c)

 

176

Figure B8: Correlation plot of slake durability index (%) vs. illite (%) where (a)

represent samples from GHN, (b) represent samples from all other rock piles and (c)

represent samples from drill cores, colluvium and the debris flow.

(a) (b)

(c)

 

177

Figure B9: Correlation plot of point load strength index (MPa) vs. kaolinite (%) where

(a) represent samples from GHN, (b) represent samples from all other rock piles and (c)

represent samples from drill cores, colluvium and the debris flow.

(a) (b)

(c)

 

178

Figure B10: Correlation plot of slake durability index (%) vs. kaolinite (%) where (a)

represent samples from GHN, (b) represent samples from all other rock piles and (c)

represent samples from drill cores, colluvium and the debris flow.

(a) (b)

(c)

 

179

Figure B11: Correlation plot of point load strength index (MPa) vs. K Feldspar (%)

where (a) represent samples from GHN, (b) represent samples from all other rock piles

and (c) represent samples from drill cores, colluvium and the debris flow.

(a) (b)

(c)

 

180

Figure B12: Correlation plot of slake durability index (%) vs. K Feldsppar (%) where (a)

represent samples from GHN, (b) represent samples from all other rock piles and (c)

represent samples from drill cores, colluvium and the debris flow.

(a) (b)

(c)

 

181

Figure B13: Correlation plot of point load strength index (MPa) vs. plagioclase (%)

where (a) represent samples from GHN, (b) represent samples from all other rock piles

and (c) represent samples from drill cores, colluvium and the debris flow.

(a) (b)

(c)

 

182

Figure B14: Correlation plot of slake durability index (%) vs. plagioclase (%) where (a)

represent samples from GHN, (b) represent samples from all other rock piles and (c)

represent samples from drill cores, colluvium and the debris flow.

(a) (b)

(c)

 

183

Figure B15: Correlation plot of point load strength index (MPa) vs. quartz (%) where (a)

represent samples from GHN, (b) represent samples from all other rock piles and (c)

represent samples from drill cores, colluvium and the debris flow.

(a) (b)

(c)

 

184

Figure B16: Correlation plot of slake durability index (%) vs. quartz (%) where (a)

represent samples from GHN, (b) represent samples from all other rock piles and (c)

represent samples from drill cores, colluvium and the debris flow.

(a) (b)

(c)

 

185

Figure B17: Correlation plot of point load strength index (MPa) vs. smectite (%) where

(a) represent samples from GHN, (b) represent samples from all other rock piles and (c)

represent samples from drill cores, colluvium and the debris flow.

(a) (b)

(c)

 

186

Figure B18: Correlation plot of slake durability index (%) vs. smectite (%) where (a)

represent samples from GHN, (b) represent samples from all other rock piles and (c)

represent samples from drill cores, colluvium and the debris flow.

(a) (b)

(c)

 

187

Figure B19: Correlation plot of point load strength index (MPa) vs. epidote (%) where (a)

represent samples from GHN, (b) represent samples from all other rock piles and (c)

represent samples from drill cores and scars.

(a) (b)

(c)

 

188

Figure B20: Correlation plot of slake durability index (%) vs. epidote (%) where (a)

represent samples from GHN, (b) represent samples from all other rock piles and (c)

represent samples from drill cores, colluvium and the debris flow.

(a) (b)

(c)

 

189

Figure B21: Correlation plot of point load strength index (MPa) and slake durability

index (%) vs. andesite (%) where (a) represent samples from GHN and (b) represent

samples from drill cores, colluvium and the debris flow.

Figure B22: Correlation plot of point load strength index (MPa) vs. amalia (%) where (a)

represent samples from GHN and (b) represent samples from drill cores, colluvium and

the debris flow.

(a) (b)

(b) (a)

 

190

Figure B23: Correlation plot of slake durability index (%) and point load strength index

(MPa) vs. argillic (%) where (a) represent samples from GHN, (b) represent samples

from drill cores, colluvium and the debris flow (c) represent samples from GHN.

(a)

(c)

(b)

 

191

Figure B24: Correlation plot of slake durability (%) (a) and point load strength index

(MPa) (b) vs. propylitic (%) of GHN samples.

(b) (a)

 

192

Figure B25: Correlation plot of slake durability (%) and point load strength index (MPa)

vs. QSP (%) where (a) represent samples from GHN, (b) represent samples from all drill

cores, colluviums and debris flow and (c) represent point load strength indices for

samples from GHN.

(c)

(a) (b)

 

193

Figure B26: Correlation plot of slake durability index (%) vs. andesite (%) where (a)

represent samples from GHN, (b) represent samples from all other rock piles and (c)

represent samples from drill cores, colluvium and the debris flow.

(b) (a)

(c)

 

194

y = 0.2x - 19.5R² = 0.3

0

1

2

3

4

5

6

7

8

80 85 90 95 100

Poin

t Loa

d St

reng

th In

dex (

MPa

)

Slake Durability Index %

y = 0.5x - 45.7R² = 0.3

0

1

2

3

4

5

6

7

8

9

86 88 90 92 94 96 98 100

Poin

t Loa

d St

reng

th In

dex

(MPa

)

Slake Durability Index %

Figure B27: Correlation plot of slake durability index (%) vs. point load strength index

(MPa) of the pit unweathered samples.

Figure B28: Correlation plot of slake durability index (%) vs. point load strength index

(MPa) of the Goat Hill North rock pile samples.

 

195

y = 0.03x - 0.85R² = 0.01

0

0.5

1

1.5

2

2.5

3

3.5

4

90 92 94 96 98 100

Poin

t Loa

d St

reng

th In

dex (

MPa

)

Slake Durability Index %

y = 0.2x - 15.3R² = 0.4

0

1

2

3

4

5

6

7

80 85 90 95 100

Poin

t Loa

d St

reng

th In

dex

(MPa

)

Slake Durability Index %

Figure B29: Correlation plot of slake durability index (%) vs. point load strength index

(MPa) of the Sugar Shack South rock pile samples.

Figure B30: Correlation plot of slake durability index (%) vs. point load strength index

(MPa) of the Sugar Shack South rock pile samples.

 

196

y = 0.7x - 62.2R² = 0.1

0

1

2

3

4

5

6

7

98 98.5 99 99.5 100

Poin

t Loa

d St

reng

th In

dex

(Mpa

)

Slake Durability Index %

Figure B31: Correlation plot of slake durability index (%) vs. point load strength index

(MPa) of the debris flows samples.

 

197

APPENIDX C. SUMMARY COMPARISM STATISTICS OF THE STRENGTH and DURABILITYCLASSIFICATION FOR QUESTA MATERIALS.

1. HYPOTHESIS NUMBER 1

Is there a difference in slake durability indices between the unweathered samples from drill core, the GHN rock pile and the other rock riles combined?

1.2 TECHNICAL APPROACH

Histograms are shown in Fig. C1 Results are below. The Mann-Whitney Rank Sum test (SigmaStat@) was used for the test. If the H statistic is small, the average ranks observed for the groups are approximately the same. If the H statistic is large, the variability among the average ranks is larger than expected from random sampling, i.e. the samples are from different populations. The P value is the probability of being wrong.

1.3 RESULTS

Table C1: Comparisons of slake durability indices of unweathered drill core samples with GHN rock pile samples and other rock pile samples excluding GHN where the t-test could not be applied because the normality test failed (i.e. distribution of data is not normal) and Mann-Whitney Rank Sum Test was used.

Comparison of Units N Median (%)

25% 75% T P Conclusion

Unweathered (Drill core) 30 95.5 94.1 97.4 1311.5 0.127

Statistically similar

GHN Rock pile 76 96.8 95.7 97.7

Unweathered (Drill core) 30 95.5 94.1 97.4 935 0.003

Statistically different

Other Rock plies (SSS,SSW,MID,SPR) 52 97.6 96.6 98.7

1.4 CONCLUSIONS:

The difference in the median values between the two groups (Unweathered drill core and GHN rock pile samples) is not great enough to exclude the possibility that the difference is due to random sampling variability; there is not a statistically significant difference (P = 0.127)

 

198

The difference in the median values between the two groups (Unweathered drill core and other rock piles samples) is greater than would be expected by chance; there is a statistically significant difference (P = 0.003)

2. HYPOTHESIS NUMBER 2

Is there a difference in point load strength indices between the unweathered samples from drill core, the GHN rock pile and the other rock piles combined?

2.2 TECHNICAL APPROACH

Histograms are shown in Fig. C2. Results are below. The t-test (SigmaStat@) was used for the test.

2.3 RESULTS

Table C2: Comparisons of point load strength of unweathered drill core samples with GHN rock pile samples and other rock pile samples excluding GHN where the t-test passed (i.e. distribution of data are normal).

Comparison of Units N Mean (MPa) Std. Deviation SEM Conclusion

Unweathered (Drill core) 30 3.6 1.6 0.3 Statistically similar

GHN Rock pile 31 4.2 1.8 0.3

Unweathered (Drill core) 30 3.6 1.6 0.3 Statistically similar

Other Rock plies (SSS,SSW,MID,SPR) 38 3.3 1.4 0.3

2.4 CONCLUSIONS:

The difference in the mean values of the two groups (Unweathered and GHN rock piles) is not great enough to reject the possibility that the difference is due to random sampling variability. There is not a statistically significant difference between the input groups (P = 0.157).

The difference in the mean values of the two groups (Unweathered and other rock piles) is not great enough to reject the possibility that the difference is due to random sampling

 

199

variability. There is not a statistically significant difference between the input groups (P = 0.569).

Slake Durability Index %70 80 90 100

Cou

nts

0.0

1.0

2.0Rubble Zone

Slake Duarability Index %70 80 90 100

Cou

nts

0.0

1.0

2.0

3.0Colluvium

Slake Durability Index %70 75 80 85 90 95 100

Cou

nts

0.0

1.0

2.0Unit U

Slake Durability Index %70 75 80 85 90 95 100

Cou

nts

0

1

2

3

4

5Unit O

Slake Durability Index %70 80 90 100

Cou

nts

0.0

1.0

2.0Unit J

Slake Durability Index %70 80 90 100

Cou

nts

0.0

0.5

1.0

1.5

2.0Unit N

 

200

Slake Durability Index %70 80 90 100

Cou

nts

0.0

1.0Unit C-I

Slake Durability Index %70 80 90 100

Cou

nts

0

1

2

3

4

5

6Unstable GHN

Slake Durability Index %70 80 90 100

Cou

nts

0

5

10

15

20

25

30

35Goat Hill North

Slake Durability Index %70 80 90 100

Cou

nts

0

1

2

3

4

5

6

7

8Spring Gulch

Slake Durability Index %70 80 90 100

Cou

nts

0

2

4

6

8

10

12Sugar Shack South

Slake Durability Index %70 80 90 100

Cou

nts

0

1

2

3

4

5

6

7Sugar Shack West

 

201

Slake Durability Index %70 80 90

Cou

nts

0

1

2

3

4

5

6

7Debris Flows

Slake Durability Index %70 80 90 100

Cou

nts

0

2

4

6

8

10Drill Core (Unweathered)

Figure C1: slake durability histogram plots for the various locations.

 

202

Point Load Strength Index (MPa)0 2 4 6 8 10

Cou

nts

0.0

1.0Unit K

Point Load Strength Index (MPa)0 2 4 6 8 10

Cou

nts

0.0

1.0Unit O

Point Load Strength Index (MPa)0 2 4 6 8 10

Cou

nts

0.0

1.0

2.0Unit J

Point Load Strength Index (MPa)0 2 4 6 8 10

Cou

nts

0.0

1.0Unit N

Point Load Strength Index (MPa)0 2 4 6 8 10

Cou

nts

0

1

2

3

4

5

6

7

8Goat Hill North

Point Load Strength Index (MPa)0 2 4 6 8 10

Cou

nts

0.0

1.0

2.0Spring Gulch

 

203

Point Load Strength Index (MPa)0 2 4 6 8 10

Cou

nts

0.0

1.0

2.0

3.0Sugar Shack South

Point Load Strength Index (MPa)0 2 4 6 8 10

Cou

nts

0

1

2

3

4

5Sugar Shack West

Point Load Strength Index (MPa)0 2 4 6 8 10

Cou

nts

0

2

4

6

8

10

12

14All Rock Piles

Point Load Strength Index (MPa)0 2 4 6 8 10

Cou

nts

0.0

1.0

2.0

3.0Debris Flow

Point Load Strength Index (MPa)0 2 4 6 8 10

Cou

nts

0.0

1.0

2.0Alteration Scars

Point Load Strength Index (MPa)0 2 4 6 8 10

Cou

nts

0

1

2

3

4

5Drill Core (Unweathered)

Figure C2: Point load strength histogram plot for the various locations.