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GEOTECHNICAL DESIGN REPORT ROUTE 191 EMBANKMENT STABILIZATION NEWPORT, VERMONT VTRANS NEWPORT STP 1343(22) CONTRACT PS0475 Submitted To: Vermont Agency of Transportation Construction and Materials Bureau 2178 Airport Road, Unit-B Berlin, VT 05641-8628 Attention: Callie Ewald, PE Submitted By: Golder Associates Inc. 670 North Commercial Street, Suite 103 Manchester, NH 03101 USA Distribution: E-file – Vermont Agency of Transportation 1 Copy – Golder Associates Inc. November 2017 Project No. 1668897
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November 8, 2017 Project No.: 1668897
Callie Ewald, PE Vermont Agency of Transportation Construction and Materials Bureau 2178 Airport Road, Unit-B Berlin, VT 05641-8628
RE: GEOTECHNICAL DESIGN REPORT ROUTE 191 ROADWAY EMBANKMENT NEWPORT, VERMONT VTRANS NEWPORT STP 1343(22) CONTRACT NUMBER PS0475
Dear Ms. Ewald:
Golder Associates Inc. (Golder) is pleased to submit to the Vermont Agency of Transportation (VTrans) this Geotechnical Design Report for the embankment slide stabilization on Route 191 in Newport, Vermont. Golder has been working on the final design elements for the slide stabilization since August 2015. This report provides a brief summary of background project information and focuses on final design elements for: the groundwater extraction system for the deep slide stabilization; regrading and drainage provisions for the upper embankment slope shallow stabilization; slide headscarp sealing; and, our evaluations of the stability of a new proposed access road to the extraction well site area.
Our work was conducted in accordance with the scope, schedule, and budget described in our proposal dated January 27, 2017, and your Notice to Proceed dated February 2, 2017. The terms and conditions governing the work are stated in our On-Call Geotechnical Services agreement with VTrans (Contact No.: PS0475). It has been a pleasure working with VTrans on this project. Please contact us if you have any questions concerning our report or require additional information.
Sincerely,
GOLDER ASSOCIATES INC. Jeffrey D. Lloyd, PE Kevin Killoran, PE Senior Project Engineer Senior Engineer Jay R. Smerekanicz, PG Christopher C. Benda, PE Associate and Senior Consultant Practice Leader Mark S. Peterson, PE Principal
JDL/drb
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Table of Contents
EXECUTIVE SUMMARY ........................................................................................................................ ES-1 1.0 INTRODUCTION .............................................................................................................................. 1
1.1 Site Conditions ............................................................................................................................. 1 1.2 Site and Project History ................................................................................................................ 2
2.0 SUBSURFACE EXPLORATIONS ................................................................................................... 5 2.1 Previous Explorations .................................................................................................................. 5 2.2 2017 Access Road Explorations .................................................................................................. 5
2.2.1 Test Boring Explorations .......................................................................................................... 6 2.2.2 DCP Probes ............................................................................................................................. 6
3.0 LABORATORY TESTING ................................................................................................................ 7 3.1 Prior Laboratory Testing ............................................................................................................... 7 3.2 2017 Testing................................................................................................................................. 8
4.0 SUBSURFACE CONDITIONS ......................................................................................................... 9 4.1 Summary of Sitewide Subsurface Condition ................................................................................ 9
4.1.1 Soil Conditions ......................................................................................................................... 9 4.1.2 Bedrock Conditions ................................................................................................................ 10 4.1.3 Groundwater Conditions ........................................................................................................ 11
4.2 Conditions at Proposed Access Road ....................................................................................... 11 5.0 GROUNDWATER MODELING ...................................................................................................... 13 6.0 FINAL DESIGN EVALUATIONS .................................................................................................... 15
6.1 General ....................................................................................................................................... 15 6.2 Deep-Seated Slide Stabilization – Groundwater Extraction System ......................................... 15
6.2.1 Extraction Well Design ........................................................................................................... 18 6.2.2 Well Screen Filter Pack .......................................................................................................... 20 6.2.3 Entrance, Approach and Uphole Velocity Estimates ............................................................. 21 6.2.4 Pump and Pump Controls ...................................................................................................... 22
6.3 Upper Embankment Slope Stabilization .................................................................................... 24 6.3.1 Slope Flattening ..................................................................................................................... 24 6.3.2 Toe Drain ............................................................................................................................... 24 6.3.3 Existing Drainage Systems in Stability Berm Area ................................................................ 25
6.4 Headscarp Seal .......................................................................................................................... 26 6.5 Cutoff Trench Drain .................................................................................................................... 27 6.6 Access Road Stability ................................................................................................................ 28
6.6.1 Stability Analysis .................................................................................................................... 28 6.6.2 Stabilization Provisions .......................................................................................................... 29
7.0 CONSTRUCTION AND POST-CONSTRUCTION CONSIDERATIONS ....................................... 30 7.1 Deep-Seated Slide Extraction Well Construction Considerations ............................................. 30
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7.2 Upper Embankment Slope and General Site Construction Considerations .............................. 30 7.3 Geotechnical Instrumentation .................................................................................................... 31 7.4 Post-Construction Groundwater Sampling and Analysis ........................................................... 31
8.0 CLOSING AND LIMITATIONS ....................................................................................................... 32
List of Tables Table 1 Chronology of Key Project Events Table 2 400-Series Boring and Piezometer Summary Table 3 DCP Test Results Summary Table 4 Soil Testing Results Summary Table 5 (in text) Well Construction Details and Projected Pumping Water Levels Table 6 (in text) Extraction Well Screen Design Criteria Table 7 (in text Estimated Total Dynamic Head (TDH) and Pump Design Parameters
List of Figures Figure 1 Site Location Map Figure 2 Existing Conditions (2012) and Locations of Borings and Instrumentation
Installed from 1966 to 2013 Figure 3 Recommended Stabilization Features and Locations of 2017 Explorations Figure 4 Cross Section A-A’ Geotechnical Data Figure 5 (in text) Extraction Well Stratigraphic Cross Section Figure 6 (in text) Selection of Filter Pack and Well Screen Slot Size Figure 7 Potential Trenching Impact on Horizontal Drains Figure 8 Typical Headscarp Seal Section & Geomembrane Tie-In Underdrain Detail
List of Appendices Appendix A 400 Series Boring Logs Appendix B Laboratory Test Results
B-1 - From 400-Series Boring Samples B-2 - 200- and 300-series Boring Sieve Analyses Used for Extraction Well Design
Appendix C Groundwater Modeling Appendix D Total Dynamic Head Worksheets Appendix E Manufacturer’s Pump Curve and Performance Specifications Appendix F Specifications Appendix G Access Road Global Stability Results
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EXECUTIVE SUMMARY Slope movements at an embankment fill constructed for Route 191 connecting Interstate 91 and Newport,
Vermont have been the subject of investigations, mitigation construction and monitoring by the Vermont
Agency of Transportation (VTrans) for over 45 years since 1971. Mitigation measures, subsurface
investigations and stability analyses in 1971-1991 concluded that continuous slope movements resulted
from embankment fill loads and groundwater pressure effects on a circular slip surface extending from the
uphill side of the roadway to the downslope toe of the embankment fill. Mitigation measures constructed in
1991 based on this hypothesis were ineffective. Based on monitoring data, additional subsurface
investigations, and stability analyses completed 1991 to present, VTrans concluded roadway slope
movements are part of a much larger non-circular slide mass extending up to 120 feet below ground surface
These later studies indicate a complex combination of geology, groundwater conditions, creep behavior,
and soil strength characteristics are causing the slope movements, all of which directly bear on an effective
mitigation plan to monitor and preferably arrest future slope movements.
In 2011 VTrans evaluated mitigation alternatives including stability berm removal; embankment
replacement; pile or drilled shaft reinforcement; and drainage of groundwater pressure. VTrans concluded
reduction of groundwater pressures would probably be the most effective stabilization method; however,
developing cost effective measures to sufficiently reduce groundwater pressures would require further
evaluation, and additional laboratory testing was warranted to better understand the creep behavior of the
site soils and related risks to long term roadway stability.
In 2012 Golder assisted VTrans in developing a plan to manage future slope movements. Following a
review of the extensive records of site and project information, and performing a preliminary reassessment
of slide mass stability, Golder developed a long-term, sustainable monitoring plan coupled with
recommendations for additional site investigations and testing to fill data gaps, develop design plans to
mitigate slope movements, and manage risk.
In 2013, VTrans requested Golder conduct an extensive geotechnical and hydrogeologic investigation,
including the installation of remote instrumentation to monitor slope movements and groundwater levels.
Twenty-two (22) additional investigation locations were included in the program, including borings advanced
using both sonic and conventional drive and wash drilling techniques, to depths up to 183 feet. The drilling
program augmented existing geologic, geotechnical, and hydrogeologic knowledge, and included additional
monitoring wells, piezometers and inclinometers to further monitor site conditions.
In 2014 – 2015, following completion of the field program, Golder refined the geologic, geotechnical and
hydrogeological conceptual models of the site to evaluate potential remedial options to slow landslide
movement. Based on the importance of groundwater pressures directly bearing on landslide movement, a
calibrated numerical groundwater flow model, based on the refined conceptual geologic/
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geotechnical/hydrogeologic models, was used to simulate the reduction in pore pressure under various
groundwater withdrawal scenarios, which were used in slope stability models to evaluate the reduction in
sliding. The ultimate remedial design approach included active groundwater extraction wells placed on
VTrans property.
In 2016 - 2017, Golder conducted additional evaluations to support the final remedial design. These tasks
included: groundwater testing; extraction well system design; upgradient impact evaluation; headscarp
infiltration reduction design; cutoff trench design; upper slope surficial improvements; trench drain design;
and existing drainage design improvements.
This report provides documentation of these evaluations not presented previously, including field
investigations conducted in 2017, results of the groundwater modeling, geotechnical design, and
construction considerations.
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1.0 INTRODUCTION This report summarizes the basis and recommendations for final design of landslide stabilization systems
for embankment fills forming a portion of Route 191 in Newport, Vermont approximately 1.2 miles northwest
of Interstate I-91 as shown on Figure 1. The design represents the culmination of investigations, attempted
mitigation construction, and evaluations of slope movement stabilization alternatives that have been
ongoing at this site since the roadway was constructed in 1971. Since 2008 a large slide mass has been
known to be present along a non-circular slide plane extending about 120 feet (ft) below ground surface
and 600 ft long between Route 191 and the Clyde River to the north. Subsequent monitoring of slope
movements and groundwater pressures combined with detailed field investigations and testing led to the
development of alternative conceptual stabilization plans for the deep-seated slide mass as well as for
shallow slide areas on the upper embankment fill slopes. Working in collaboration with VTrans and their
civil design consultant Stantec of South Burlington, Vermont, Golder completed a preliminary design
process and then a final design for an extraction well stabilization system for the deep-seated slide mass
and a slope reconstruction and drainage design for the shallow upper slope area. This report briefly
summarizes the history of work leading to the development of the stabilization alternatives considered
during preliminary design, and then describes the rationale, supporting analytical methods and details for
the recommended final stabilization design.
1.1 Site Conditions Existing site conditions in the general area of the Route 191 embankment slope movements are shown on
Figure 2 and include the following primary features:
Route 191 roadway settlements have occurred since 1971 primarily in the section between Stations 111+00 and 119+00. The road grade drops about 45 ft downhill to the west within the subject area.
The approximate location of a landslide headscarp (apparent upslope boundary based on abrupt ground displacement) of the slide mass observed in March 2012 is shown on Figure 2. The headscarp passes roughly along the toe of the uphill embankment fill slope at about Station 115+00, crossing the roadway at about Station 112+50 to the east and Station 117+50 to the west, and extends east and west on the downslope north of the roadway where the edges of the headscarp are not evident.
The slope on which the fill embankment is located extends about 500 ft uphill from Route 191 and about 600 ft downhill.
The upslope topography is believed to be unchanged since original road construction and includes wooded slopes typically at about 2.5H:1V. A narrow ravine provides surface water drainage for the eastern portion of the slope drainage and carries flow to a 30-inch diameter culvert headwall located at about Station 112+00 on the south side of the roadway embankment.
Site conditions downslope of Route 191 include the slide mass area and slopes, benches and waterways extending down from the edge of road pavement including:
The grass covered embankment fill slope.
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A grass covered horizontal bench about 40 ft wide forming the crest of a stabilizing berm placed in 1991.
An abandoned power canal (partially filled with water) that previously carried water from the Great Bay Hydro Dam (previously the Citizen’s Canal Dam) east of the site to a penstock and turbine located west of the site.
Wooded and undulating flatter terrain dropping about 30 ft in elevation over roughly a 200 ft distance to the Clyde River at the base of the slope.
The ground surface topography shown on Figure 2 is based on survey information provided by VTrans1
and reflects cut/fill slopes and natural slopes. The extent of the slide mass directly beneath the roadway is
evident from the sag (settlement) of the roadway surface grade and the downward warp of the guardrail
along the north edge of pavement. The fill slopes of the roadway embankment are generally at 2H:1V, with
localized areas as steep as about 1.4H:1V. Secondary surficial scarp features (indicative of shallow
sloughs or slides) are present within the western portion of the embankment fill slope (approximately Station
116+00 to 119+00). Natural slopes above the abandoned power canal are generally much steeper than
the terrain below the Great Bay Hydro access road. Above the canal, natural slopes typically vary from
about 1.6H:1V to 6H:1V, with occasional areas showing signs of shallow instability and surface creep
(tilting trees, bowed tree trunks, slumps). Below the Great Bay Hydro access road the ground surface is
relatively flat (generally about 10H:1V), undulating and wet.
1.2 Site and Project History Slope movements of the embankment have been the subject of geotechnical investigations, slide repairs
and monitoring by VTrans for over 45 years since the roadway was constructed in 19712. The history of
construction, slope movements, road repairs, investigations and mitigation activities has previously been
summarized by VTrans3,4 and Civil Engineering Associates (CEA)5. A chronology of key project events is
listed in Table 1.
Mitigation measures, subsurface investigations and stability analyses completed over the 20 year period
from 1971 to about 1991 concluded that continuous slope movements were relatively shallow and the result
of embankment fill loads. A stability berm constructed in 1991 at the toe of the embankment fill proved to
be ineffective. Based on monitoring data, additional subsurface investigations and stability analyses
completed from 1991 to 2011, the roadway slope movements were concluded to be part of a much larger
non-circular slide mass extending up to 120 ft below ground surface and affect an overall slope length of
1 VTrans (2012). Base map titled “Newport VT 191 Revised Bore Plan 020409.DGN”, dated March 20, 2012. 2 Golder Associates Inc.(2012). “Review of Landslide Records and Analyses, Route 191 Embankment, Newport, Vermont”, VTrans Newport STP 1343(22), Contract PS0172, Project No. 123-87445, November 29, 2012. 3 A-Baki, S. and Batchelder-Adams, C. (1989). Slide Remediation Report for Derby-Newport F134-3(19), Materials and Research Division, Vermont Agency of Transportation, November 1989. 4 Allen, C. and Benda, C., VTrans (2011). VT-191 in Newport, VT – A Landslide Case History, presented at American Society of Civil Engineers (ASCE) Geo-Institute Landslide Conference, Norwich University, Norwich, VT, April 23, 2011. 5 Civil Engineering Associates, Inc. (2011). Geotechnical Report, “Creep Deformation Analysis, Slope Movements on Vermont Route 191 – Newport, Vermont”. Prepared for Vermont Agency of Transportation, Newport City STP 134-3(22), Contract No. PS0077. December 1, 2011.
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roughly 600 ft. The mechanisms causing the deep seated slope movements include a complex combination
of geologic stratigraphy, groundwater conditions, and soil strength characteristics.
In 2012 Golder reviewed the body of investigative work completed for the site and identified several data
gaps to be addressed before mitigation design could be undertaken. The findings from that review are
presented in our 2012 report2. To address the data gaps Golder completed a series of site investigations,
field and laboratory testing, and installed in-situ instrumentation systems in 2013 and 2014. The data
produced from this work are summarized in our Geotechnical Data Report (GDR) dated August 22, 20146.
In 2014 and 2015 Golder completed groundwater modeling and stability analyses using the new data and
evaluated slide stabilization alternatives for the deep-seated slide mass. At our February 12, 2015 meeting
with VTrans we described the revised analyses of the deep-seated slide mass and assessments of
stabilization alternatives. The tasks involved with the revised analyses included refinement of the site
geologic model, creation of groundwater 3D numerical model using MODFLOW software, and updating the
slope stability model for the deep-seated slide mass using updated stratigraphy and pore water pressure
inputs from MODFLOW. The combined groundwater and stability models were then used to evaluate four
potential stabilization alternatives for lowering groundwater pressures on the deep slide plane with passive
and/or active groundwater extraction systems. In July 2015 VTrans selected the alternative with three
active extraction wells located on the stability berm below Route 191, and requested Golder to proceed
with preliminary and final design for the well system to stabilize the deep-seated slide. Preliminary design
plans were presented to VTrans in December 2015, and work on the final design was performed in 2016
and 2017.
In addition to the deep-seated slide movements Golder identified surficial slope displacements occurring at
the western portion of the upper embankment slope adjacent to the north side of Route 191. Although
these movements were located within the boundaries of the larger slide area, the mechanisms causing the
movements are separate from those affecting the deep-seated slide and a different set of stabilization
alternatives were evaluated for the upper slope slide areas. A summary of the analyses of the upper slope
stability and stabilization alternatives is discussed in Golder’s 20157 letter report. In July 2015 VTrans
selected an upper slope stabilization plan including the installation of an 8-ft deep trench drain along the
toe of the upper slope at the level of the stability berm and flattening the upper slope by placing additional
fill above the stability berm to achieve a 2.1H:1V slope. Golder was requested to proceed with preliminary
and final design of the plan to stabilize the upper slope. Preliminary design plans were presented to VTrans
in June 2016, and work on the final design was performed in 2016 and 2017.
6 Golder Associates Inc. (2014). “Geotechnical Data Report, Route 191 Embankment, Newport, Vermont”, VTrans Newport STP 1343(22), Contract PS0172, Project No. 133-87312, August 22, 2014. 7 Golder Associates Inc. (2015). “Summary of Deep-Seated and Upper Slope Stability Analyses”. July 14, 2015.
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In 2015 VTrans engaged Stantec to provide civil design services for the reconstruction of Route 191 as part
of the stabilization work and to work together with Golder to provide preliminary and final design drawings
and specifications for the project. Stantec developed conceptual drawings in August 2016 and preliminary
drawings in April 20178 that included input from Golder for the geotechnical aspects of the work including
preliminary plans and details for the extraction well system, the upper slope stabilization, sealing the slide
headscarp, and installation of a groundwater cutoff trench across Route 191 upgradient of the slide area.
As part of this plan development Stantec developed preliminary plans and profiles for a new permanent
access road located from Route 191 to the extraction well system to be installed on the stability berm as
shown on Figure 3. Due to concerns for the stability of cuts and fills required to construct the access road,
Golder completed an additional field investigation in early 2017 in this area of the site and evaluated the
global stability of the access road fills.
8 Stantec (2017). Drawings titled “Preliminary Plans, Proposed Improvement, Newport City, County of Orleans, VT Route 191 (Principal Arterial)”, State of Vermont, Agency of Transportation, Project No. STP 134-3(22), February 10, 2017, provided to Golder April 5, 2017.
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2.0 SUBSURFACE EXPLORATIONS Several subsurface exploration and testing programs have been completed at the site to assess soil,
bedrock and groundwater conditions and to install instrumentation systems over the past 45 years and are
described in detail in Golder’s 20121 and 20146 reports. Section 2.1 briefly describes the investigations
completed prior to 2017. Section 2.2 describes the exploration program completed in early 2017 for the
stability assessment of the new gravel roadway planned to provide access to the extraction well area on
the stability berm.
2.1 Previous Explorations VTrans completed subsurface explorations at the site in 1966 prior to embankment construction and during
three periods after construction: 1971 to 1974; 1989; and 2006 to 2009. As part of the 2006 to 2009
investigations VTrans installed initial instrumentation systems to monitor the behavior of the deep-seated
slide mass. During installation of two inclinometers adjacent to the Clyde River in late 2009, significant
artesian water pressures were encountered in confined sand layers at depth. The relief of artesian
pressures at the inclinometer boreholes resulted in lower hydraulic heads in monitoring wells near the
roadway, indicating hydraulic connectivity within confined hydraulic layers across the site.
Based on the data gaps identified in Golder’s 2012 report2, an extensive site investigation was completed
in 2013 that included twenty two (22) borings advanced using sonic and conventional cased-wash borings.
These explorations were conducted to better assess the complex site stratigraphy, obtain undisturbed
samples for laboratory testing, and to install piezometer and inclinometer instruments. To study the
hydrogeologic nature of the coarser sediment layers, eight open-standpipe piezometers were installed at
within three layers of interest, seven borings contained multilevel vibrating-wire piezometers grouted in
place, and three 4-inch pumping test wells were installed through the stability berm and screened in the
three coarsest layers. The 4-inch wells were used during a series of pumping tests conducted in August
2013 to assess hydraulic characteristics. Additional instrumentation installed in 2013 included two In-Place-
Inclinometer (IPI) arrays, and two ShapeAccelArray™ (SAA) inclinometers installed along the shoulder of
Route 191. Details of the 2013 investigation and laboratory testing are included in Golder’s 2014 data
report6 and details about the series of pumping tests are included in Golder’s pumping test report9.
2.2 2017 Access Road Explorations In March and April 2017 three borings and 20 Dynamic Cone Penetrometer (DCP) probes were made at
the locations shown on Figure 3 in the western portion of the planned access road to the extraction well
area and in the eastern upper embankment slope area. The explorations were made to assess the stability
of cut and fill sections of the access road where subsurface conditions had not previously been investigated
9 Golder Associates, Inc. (2014). “Pumping Test Investigation, Route 191 Embankment Slide, Newport, Vermont”, Project No. 133-87312, August 22, 2014. Included as Appendix G in Golder’s Geotechnical Data Report dated August 22, 2014 (Ref 2).
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and to confirm existing surficial conditions assumed for the eastern upper slope stabilization area. The
exploration locations shown on Figure 3 were approximated from measurements to existing site features
and ground surface elevations at the explorations were estimated based on the topographic contours shown
on Figure 3.
2.2.1 Test Boring Explorations In March 2017 a VTrans drilling crew completed three borings (B-401, B-402, and B-403) at the locations
shown on Figure 3 with a CME-55 track rig. The borings were advanced using wash boring methods to
depths of 30 to 50 ft below ground surface. A Golder geotechnical engineer was on site during the
advancement of the test borings to monitor drilling activities, log the borings, and obtain soil samples.
Details of the sampling methods used, field data obtained, and soil conditions encountered are presented
on the boring logs included in Appendix A. A description of the boring log symbols and terms used for the
soil and rock descriptions is provided on Table A-1 preceding the logs. A summary of the boring location
and depth information is provided on Table 2.
Standard Penetration Test (SPT) sampling was conducted in all test borings at approximately 5-ft
increments using a standard 2 inch split spoon sampler with an automatic hammer system in accordance
with ASTM D1586. All borings were terminated in soil and no rock coring was performed.
A temporary open standpipe piezometer was installed in boring B-401 located near the shoulder of Route
191 to assess local groundwater conditions in the area of the proposed access road. Details of the
piezometer installation are provided on the log for B-401 and on Table 2. The piezometer borehole was
backfilled with sand and capped with a road box mounted just below the asphalt road surface. The road
box was cemented in place with Speed Crete™.
2.2.2 DCP Probes A total of 20 of DCP probes were completed at the locations shown in Figure 3 on April 5, 2017. The testing
was conducted in accordance with ASTM D695, Standard Test Method for Use of the Dynamic Cone
Penetrometer in Shallow Pavement Applications. The DCP apparatus consists of a sacrificial 60° cone 20
millimeter (mm) in diameter connected to a 16 mm diameter steel rod. The cone is advanced using a 17.6
pound hammer dropped 575 mm and the depth of penetration caused by the blows (i.e. hammer drops) is
recorded. DCP-1 through DCP-5 were performed below the proposed access road, DCP-6 through DCP-
13 were performed between the proposed access road and Route 191, and DCP-14 through DCP-20 were
performed in eastern upper slope areas where surficial stabilization re-grading is planned. A summary of
the DCP test results is provided in Table 3.
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3.0 LABORATORY TESTING Extensive geotechnical laboratory testing of soil samples has been completed during previous
investigations to assess index and engineering properties and is presented, discussed and/or summarized
in our 20121 and 20146 reports. A limited groundwater analysis program was performed in 2015 on
groundwater samples collected from selected monitoring wells on the site. These prior testing programs
are discussed in Section 3.1. Section 3.2 discusses additional soil testing performed in 2017 on samples
collected as part of the access road investigation.
3.1 Prior Laboratory Testing As discussed in our 2012 report1, VTrans performed index and classification testing on soil samples
obtained from the 1966 to 1989 explorations, and more extensive index and engineering property testing
was performed on samples from the 2006 to 2009 explorations. Additional index and engineering property
tests were completed on soil samples collected during Golder’s 2013 field investigations. The 2013 testing
was conducted by VTrans (Construction and Materials Bureau Central Laboratory in Berlin, Vermont) and
the University of Massachusetts at Amherst under the direction of Dr. Don DeGroot, and testing results are
presented in Golder’s 2014 report6. The interpretation of these data provides the primary basis for soil
parameters used for the global stability analyses and groundwater modeling employed for the embankment
stabilization final design.
To assess the impacts of groundwater quality, if any, on the extraction well system design, Golder
completed a round of groundwater sampling from six site monitoring wells/inclinometers in 2015. The
sampling, analyses, results and interpretation are discussed in Golder’s 2015 letter report10. Each
groundwater sample was analyzed for major cation/anion species, and for Resource Conservation and
Recovery Act (RCRA) 8 metals that the United States Environmental Protection Agency (USEPA) uses for
primary and secondary drinking water standards. In general, the analytical results show that the inorganic
groundwater parameters sampled from monitoring wells and inclinometers screened within the lower sands
and gravels exist at concentrations below the standard limits of the Vermont Groundwater Quality
Standards (VGQS) and the United States Environmental Protection Agency’s Maximum Contaminant
Levels (USEPA MCLs). As presented in email correspondence between Rick Levey of the Vermont
Department of Environmental Conservation (DEC), Watershed Management Division, and Bruce Martin of
VTrans dated June 12, 2015, Golder understands that groundwater discharge from the groundwater
extraction system discussed herein would not violate water quality standards or pose a risk to aquatic biota
in the Clyde River. Furthermore, Golder understands that the DEC approves of the discharge and has
requested VTrans perform post-construction groundwater sampling to further document iron and
manganese concentrations. In additions to iron and manganese testing, Golder recommends testing the
10 Golder Associates Inc. (2015). Letter report titled “Groundwater Sampling and Analysis, Route 191 Embankment Slide, Newport, Vermont, VTrans Newport STP 1342(22)”. April 27, 2015.
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groundwater for standard field chemistry parameters including temperature, pH, specific conductance,
Eh/redox potential, dissolved oxygen, and salinity.
The potential presence of deicing compounds at one of the wells may indicate runoff from Route 191 is
migrating down the failure scarp and entering the lower sand and gravel unit. To preclude this possibility
and to enhance stability, the final slide stabilization design includes a surface seal on the slide headscarp
to limit surface water infiltration into the lower sand and gravel unit (discussed in Section 6.2.2).
3.2 2017 Testing As part of the 2017 field investigation to support design for the proposed access road, geotechnical
laboratory tests were performed by VTrans on soil samples collected to assist in soil classification. The
testing was performed in accordance with applicable AASHTO and American Society for Testing Materials
(ASTM) testing procedures and is summarized below.
Soil Laboratory Test Testing Procedure Number of Tests Completed
Grain Size Analysis, sieve only AASHTO T88, ASTM D422 20
Natural Moisture Content AASHTO T265, ASTM D2216 20
Atterberg Limits AASHTO T89 & T90, ASTM D4318 6
Direct Shear AASHTO T236, ASTM D3080 3
The three direct shear tests were run on a single composite sample collected from boring B-401 using
material collected between 15 and 27 feet below ground surface. These tests were used to evaluate the
strength of the fill material in the existing embankment in the area of the proposed access road, and the
results were compared with three direct shear tests of the fill material obtained from the center of the
embankment during the 2013 investigation.
Selected soil testing results are included on the boring logs in Appendix A and summarized on Table 4.
Complete laboratory testing results are provided in Appendix B.
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4.0 SUBSURFACE CONDITIONS The regional surficial geology and bedrock geology are described in detail in Golder’s 20121 and 20146
reports. A detailed description of soil, bedrock and groundwater conditions for the overall slide site area is
provided in Golder’s 20146 report, and a brief review of the major stratigraphic units is presented below in
Section 4.1. Boring logs providing detailed information on the conditions encountered at all project
explorations are either referenced in Golder’s 20121 report or included in in our 20146 report. Conditions
specific to the localized 2017 investigation for the proposed access road are discussed in Section 4.2.
4.1 Summary of Sitewide Subsurface Condition Evaluation of borehole log data and an assessment of bedrock surface contours indicate the bedrock
surface in the landslide area generally dips to the north, parallel to regional strike, and not parallel to the
northeasterly sloping topographic surface. Considering the bedrock slope and the similar orientation of
inclinometer displacements, the preferred direction of slide movement is interpreted to be to the north in
the general alignment of Subsurface Profile A-A’ shown on Figure 2. Profile A-A’ is shown on Figure 4 and
illustrates the major stratigraphic units interpreted to be present at the site.
4.1.1 Soil Conditions Soil deposits include a complex stratigraphy of fills and glaciolacustrine deposits consisting of interbedded
silts, fine sands, sands and gravels, silty clays and clays. The total soil thickness overlying bedrock is
interpreted to vary from roughly 172 ft at Route 191 to about 78 ft at the Clyde River. Dropstones, consisting
of ice-rafted cobbles and boulders, occur within all units, and are ubiquitous in the wooded surface areas
of the slide not affected by roadway and development construction activities. The boulders observed on
the surface are up to 6 ft or more in longest dimension.
The changes in soil layers were interpreted to generally be gradual and grade into and out of coarser
material, consistent with glaciolacustrine and fluvial deposits. Golder grouped the soil units into
distinguishable subsurface layers taking into account geological origin and engineering behavior; not all soil
layers were encountered in all of the borings. The interpreted stratigraphy is shown on Section A-A’ (Figure
4) and includes the following soil layers (in descending order):
Fill: Embankment fill was encountered under Route 191 (up to about 30 ft thick), at the stability berm (up to about 20 ft thick), and at the Great Bay Hydro Road area (about 15 ft thick). The fill material was observed to be reworked native material, probably from the roadway cuts immediately uphill and downhill of the site along Route 191. The fill is generally described as gray brown to dark gray brown, moist to wet, loose to dense, fine to coarse sand, some to trace silt, little to trace gravel, with layers of silt throughout (AASHTO: A-1-b to A-2-4 to A-4, USCS: SM).
Upper Silts and Sands: Starting at the ground surface, or at original grade in boring locations with embankment fill, is a layer of gray brown to dark brown, moist, medium dense to dense, layered fine to medium sand, fine sand, and silt, with trace fine gravel and coarse sand throughout (AASHTO: A-2-4 to A-4, USCS: SM to ML). Total thickness of this layer
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ranges from about 10 ft at to 75 ft. This layer terminates at a point above the abandoned power canal.
Upper Silts and Clays: Below the upper silts and sands is a potentially continuous layer of stiff to hard, low plasticity varved silty clay (AASHTO: A-6 to A-7-6, UCSC: CL), ranging in thickness from about 3 to 15 feet and extending from uphill of B-302 above the roadway and terminating downhill at a point around B-311.
Middle Silts and Sands: Underlying the upper silts and clays is a layer of gray, dry to moist, very dense, layered silt, silty fine to medium sand, and clayey silt, with little to trace rounded gravel throughout (AASHTO: A-4, USCS: SM to ML). Occasional layers of dark gray, fine to medium sand were also encountered in this stratigraphy. Total thickness ranges from about 15 ft to 40 ft before tapering off between the canal and B-311.
Middle Sands and Gravels: Below the middle silts and sands is a separate layer of medium brown and orange brown, moist, very dense, silts, some fine sand, and some gravel, with pockets of gray, moist, very dense, fine to medium sand (AASHTO: A-1-b to A-2-4, USCS: SM). The thickness of this layer ranges from about 10 to 15 ft before it also tapers off between the canal and B-311.
Lower Clay: Underlying the middle silts, sands, and gravels is a continuous layer of layered, dry to moist, very stiff to hard, generally high plasticity varved clayey silt and silty clay (AASHTO: A-6 to A-7-5 to A-7-6, USCS: MH, CH, and MH-CH). This lower clay layer was observed in all of the borings, ranging in thickness from about 32 ft upslope from Route 191 to about 20 ft at the stability berm to about 50 ft at the base of the slope near the Clyde River. Zones of disturbance and slickensides were noted throughout. Folded varves and reworked zones were observed in the sonic borings at the approximate depth of the failure surface identified in the historic inclinometers. Varve thickness ranges from about 0.1 inches up to 2 inches. Zones of non-varved clay up to 5 ft thick were also encountered.
Lower Sands and Gravels: Beneath the lower clay a layer of brown and gray, medium dense to very dense, fine to coarse sand, with some to little gravel and little silt (AASHTO: A-1-b to A-3, USCS: GM to SM) was encountered in all of the boring locations. Thickness of this layer ranges from 20 to 30 ft. Occasional cobbles were noted throughout.
Lower Silts and Weathered Bedrock: Directly above the bedrock surface a layer of dark brown, moist to wet, dense, silts and silty fine sands (AASHTO: A-4, USCS: ML) was encountered. The thickness of this layer is fairly consistent at 10 to 15 ft. Fractured and weathered bedrock was encountered along the bottom of the deposit immediately above intact bedrock.
4.1.2 Bedrock Conditions Bedrock was cored at the sonic borings to verify the top elevation of unweathered bedrock and diamond-
coring using an NQ sized rock core barrel was completed in boring B-305b at the edge of Route 191. The
core recovered was a medium dark to dark grey, very fine grained, fresh, strong to very strong, weakly
foliated to massive, strongly calcareous, muscovite-quartz metalimestone, with trace pyrite. Discontinuities
are mostly parallel with foliation, dipping 10-20 degrees, planar, rough, spaced 4-26 centimeters (cm; very
close to moderately spaced) with rare coatings of iron oxide. This lithology is consistent with the Waits
River formation.
Saprolite was noted in a VTrans core log for boring B-205 (115 to 141.6 ft [26.6 ft thick]). Saprolite, often
called residual soil, is defined as soft, thoroughly decomposed rock formed in place by chemical weathering,
and is characterized by preservation of structures present in the unweathered rock (e.g., bedding and
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foliation). The lower silt and weathered bedrock layer is generally consistent with the presence of saprolite.
As saprolite is generally clay rich, groundwater flow is generally restricted in saprolites.
4.1.3 Groundwater Conditions Groundwater conditions at the site were evaluated based on an interpretation of piezometer data from
boreholes located across the site and with a series of pumping tests performed from the three PTW wells
constructed on the stability berm. The results of the pumping tests and conclusions about the site
hydrogeologic properties and system related to extraction well remedial design are presented in Golder’s
pumping test report9.
Groundwater conditions as measured by piezometers indicate that groundwater appears to react quickly to
heavy rainfall events although the rise in pore pressure is slight, generally less than 1-2 ft. The piezometer
data indicate there is a noticeable downward vertical gradient in water pressures on the uphill side of the
abandoned power canal bisecting the site, and an upward vertical gradient in water pressures at and below
(north of) the canal. Artesian pressures, where the measured piezometric head elevation is above the
ground surface, range from about 10 ft at B-311 to about 20 ft at B-313 for the deep piezometers and about
0.5 ft for the shallow piezometer at B-311. The shallow piezometer at B-313 appears to react to changes
in the elevation of the Clyde River. B-316 adjacent to the power canal also shows a very strong upward
vertical gradient where the deep piezometer has a piezometric head elevation about 6 ft bgs.
4.2 Conditions at Proposed Access Road Conditions at the proposed access road on the east end of the Route 191 embankment are generally similar
to conditions encountered beneath the embankment fill in earlier investigations. Although the borings were
of limited depth (52 ft in B-401 and 32 ft in B-402 and B-403), embankment fill, upper silts and sands, upper
silts and clays, and middle silts and sands were all encountered. The upper silts and sand, upper silts and
clays, and middle silts and sands were largely as described in Section 4.1. The upper silt and clay layer
was approximately 5 ft thick and at a higher elevation than in the earlier borings, indicating that it and the
upper silts and sand layer above it rise and thin out moving towards the east.
The upper 29 ft of material encountered in in B-401 and the upper 12 ft in B-402 was embankment fill
material from the original embankment construction. This material tended to have a higher silt component
than the material tested elsewhere in the embankment (see the earlier VTrans investigations and Golder’s
2013 investigation). Similar to the earlier investigations, the fill material was observed to be reworked native
material. The fill is generally described as gray brown to tan gray, moist to wet, loose to dense, silt to silty
fine to coarse sand, little to trace gravel (AASHTO: A-1-b to A-4, USCS: SM to ML). Boring B-401 had a
zone from 20 to 29 ft bgs that was looser than embankment fill material elsewhere, and had a higher silt
content, likely due to variations in the material used to construct the embankment rather than deliberate
placement.
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DCP test results correlated to STP N-values (summarized in Table 3) were factored into an estimate of the
friction angle of the surficial soil below the vegetated mat to 3 ft bgs. The overall average STP N-value
calculated from the DCP testing in the area of the proposed access road (DCP tests DCP-1 through DCP-
13) after adjusting for obstructions encountered during the testing was equal to 24. Based on this N-value
and SPT N-values from borings B-402 and B-403, a friction angle of 35 degrees was estimated and used
in Golder’s evaluation of the access road impacts on slope stability summarized in section 6.6.
In comparison, the overall average N-value calculated from the DCP test results in the area of the proposed
upper embankment slope stabilization area (DCP-14 through DCP-20) after adjusting for obstructions
encountered during the testing was equal to 14.
Groundwater encountered in boring B-401 measured immediately after well construction was 10.7 ft bgs.
The groundwater measured at the end of drilling in borings B-402 and B-403 was 0.9 ft and 1.3 ft,
respectively.
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5.0 GROUNDWATER MODELING The conceptual hydrogeologic model of the Newport Landslide Site is controlled by recharge areas, varying
lithologies and regional discharge. In general, percolating precipitation becomes groundwater in recharge
areas south and southwest of the site and moves northeast, discharging to the Clyde River and the
abandoned power canal through the glacial sediments. The bulk of the groundwater movement occurs
predominantly in the open, interconnected pores within the coarser glacial sediments, which dip gently to
the northeast. Some groundwater recharges the underlying bedrock from the glacial sediments in the
recharge areas, which also moves to the northeast. The groundwater within the bedrock flows through a
secondary porosity developed from the joints, fractures and foliation plane openings present within the
bedrock. Primary porosity is likely not an important factor in groundwater flow in bedrock as the spaces
between primary grains have been filled with precipitated cement through the processes of diagenesis and
low-grade metamorphism. Precipitation is also collected and stored by embankment fills associated with
construction of Route 191.
Golder compiled a computer numerical groundwater model based on the conceptual hydrogeologic model
briefly described above. The numerical groundwater model was used to evaluate the following:
The overall groundwater flow directions, and the importance of the coarser grained sediments in controlling groundwater flow;
The relationship between horizontal and vertical groundwater gradients;
The effect of relieving groundwater pressure at depth;
Alternative landslide stabilization approaches using groundwater withdrawal; and
The potential effects of the selected stabilization plan on nearby, upgradient water supply wells.
Golder initially constructed the numerical groundwater model using three-dimensional geologic surface
kriging software (EVS/MVS11), employing the geologic and geotechnical boring log data, as well as surficial
geologic mapping data, to develop a model using eight (8) separate, distinct hydrogeologic layers. The
groundwater model was then developed using the three-dimensional model MODFLOW12,13. Using
observed field hydrogeologic, surface hydrology, remote instrumentation, geotechnical laboratory, and
precipitation data, we assigned model characteristics to mimic observed conditions. These characteristics
included estimates of hydraulic conductivity, anisotropy, and boundary condition values to simulate
horizontal and vertical groundwater flow, and water balance input and output. Golder then conducted a
calibration exercise to refine these values to obtain a reasonable match between observed and simulated
11 C Tech Development Corporation (2008). EVS/MVS Mining Visualization System, Vers. 9.6. 12 McDonald, M.G., and Harbaugh, A.W. (1988). A Modular Three-Dimensional Finite-Difference Groundwater Flow Model. Techniques of Water-Resources Investigations of the United States Geological Survey, Book 6, Chapter A1, U.S. Government Printing Office, Washington D.C. 13 Harbaugh, A.W., Banta, E.R., Hill, M.C., and McDonald, M.G. (2000). MODFLOW-2000, The U.S. Geological Survey Modular Ground-Water Model - User guide to modularization concepts and the ground-water flow process: U.S. Geological Survey Open-File Report 00-92, 121 p.
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conditions to compile a steady-state model for use in developing alternative extraction well stabilization
approaches. This included mimicking the results of a transient variant of the model to the observations of
the 24-hour pumping test at PTWa to further calibrate the model.
Following calibration, Golder then evaluated four groundwater extraction scenarios, including passive
pressure relief wells near the Clyde River, and three active groundwater extraction wells placed at varying
locations between the Clyde River and Route 191. For each scenario, the potential increase in the factor-
of-safety against further sliding was analyzed by taking the reduced groundwater pressures from the
groundwater model runs and incorporating them into global slope stability models. Due to access, right-of-
way and permitting issues, VTrans selected the existing stability berm for the location of three active
groundwater extraction wells for the final design. Evaluation of this scenario indicates that it likely will not
reduce the reported static groundwater elevations of water supply wells with open intervals in bedrock
located upgradient of the landslide site.
Appendix C contains a detailed description of the numerical groundwater model compilation, results, and
extraction system scenarios.
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6.0 FINAL DESIGN EVALUATIONS 6.1 General From site observations made in 20122 and the 2013 field program6, two different slope failure mechanisms
of concern were identified: 1) the deep-seated slide mass extending up to 120 ft deep with an overall slope
length of roughly 600 ft that is causing the most visible impact to the stability of Route 191; and 2), a shallow
upper slope slide mass within the embankment materials adjacent to Route 191. Final design development
for the deep-seated and shallow upper slides were based on the results of global stability analyses
discussed in detail in Golder’s 20157 letter report.
The selected design for the deep-seated slide stabilization is described as Alternative D in the 20157 letter
report, and includes the installation of three active groundwater extraction wells in the area of the stability
berm shown on Figure 3. The wells are planned to extend 146 to 180 ft bgs. The calculated global stability
factor of safety for the deep-seated slide after implementation of the groundwater extraction wells varies
from 1.27 to 1.42 for three slope cross sections (Section A-A’ shown on Figure 2 and two parallel sections
150 ft right and left of Section A-A’). The shape of the calculated potential failure surface corresponding to
the stability analysis for Section A-A’ is shown on Figure 7 of the 20157 letter report.
The selected design for the shallow upper embankment slope area is described as Alternative US-2 in the
20157 letter report. The design includes adding structural fill to flatten the slope to 2.1H:1V in the area
shown on Figure 3, and adding an 8 foot deep toe drain at the area shown on Figure 3 to lower the
groundwater level at the toe of the upper slope. The calculated global factor of safety for the upper slope
mitigation design is 1.31 as shown on Figure 13 of the 20157 letter report.
The groundwater extraction system stabilization design for the deep-seated slide mass is discussed in
Section 6.2 and the design recommendations for the shallow upper embankment slide is discussed in
Section 6.3. Additional stabilization recommendations beneficial for both the deep and shallow slide
mechanisms include headscarp sealing (discussed in Section 6.4), and a cutoff trench drain upgradient of
the slide across Route 191 (discussed in Section 6.5). Section 6.6 summarizes our evaluation of the
stability of the permanent access road planned to connect Route 191 to the extraction well and control
building area on the stability berm.
6.2 Deep-Seated Slide Stabilization – Groundwater Extraction System The Route 191 embankment is underlain by several glaciolacustrine sand/gravel/silt/clay units and overlies
embankment and fill materials placed for construction and slope stabilization. Groundwater is present in
these sediments under confining pressures. Previous VTrans field studies indicate that depressurizing
artesian conditions in the lower portion of the slide mass reduced the rate of slide mass movement. Golder’s
geotechnical and hydrogeological modeling confirmed the results of these studies2,6,7. The selected
stabilization design for the deep-seated slide uses extraction wells to reduce excess groundwater pressures
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acting on the slide plane. Design included refinement of the site geologic model; creation of a groundwater
3D numerical model using MODFLOW software; developing a slope stability model for the slide mass using
stratigraphy identified in the 2013 investigation and pore water pressure inputs from MODFLOW, and
calibration analyses to assess the behavior of the integrated model inputs. The combined groundwater and
stability models were then used to evaluate the mitigation design.
The selected mitigation design includes installation of three new groundwater extraction wells at the
locations shown on Figure 3, referred to as AW-1, AW-2, and AW-3 within the Lower Sand and Gravel unit.
This stratum exists between 120 and 175 ft bgs along the stability berm. The design incorporates existing
pumping test well PTWa, installed as part of the 2013 field investigation, as a backup extraction well. A
stratigraphic cross section illustrating the depth and location of the extraction wells is provided in Figure 5
below. In 2013, Golder completed a pumping test of well PTWa, near the proposed location of AW-1 and
AW-2. PTWa was drilled using sonic drilling techniques and was completed as a 4-inch diameter polyvinyl
chloride (PVC) well with a 5-ft screen interval between 135 and 140 ft bgs. For the pumping test, the well
was pumped for 24 hours at a constant rate of 6 gallons per minute (gpm). The static and pumping water
levels were 38.9 and 126.4 ft bgs, respectively resulting in a drawdown of 87.5 ft and a well specific capacity
of 0.07 gpm/ft. Based on the hydrogeologic testing, the estimated average transmissivity for the Lower
Sand and Gravel unit is 42.8 ft2/day and the average hydraulic conductivity is 1.65 ft/day based on a
thickness of 26 ft. The average calculated (geometric mean) storage coefficient is 4.5E-049.
Figure 5 - Stratigraphic cross section showing the extraction wells screened in the Lower
Sand and Gravel unit.
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Water quality can greatly affect the long-term operation and maintenance costs of a groundwater pumping
system due to precipitation of dissolved minerals and the formation of iron-precipitating bacteria, which can
plug the gravel pack, the well screen, pump intake screens, the pump column pipe, and associated
distribution piping. Mineral precipitation and iron-precipitating bacteria were observed at the horizontal
drain outlets in 2012 (see Section 6.3.3). Water quality sampling results of the Lower Sand and Gravel unit
indicate that the groundwater contains concentrations of dissolved iron (up to 3.1 milligrams per liter [mg/L]),
total iron (up to 18 mg/L), total manganese (up to 0.88 mg/L), and total dissolved solids in excess of 500
mg/L10. These concentrations are considered highly elevated for drinking water standards but do not
necessarily indicate the potential for well plugging. The fine-grained matrix of the Lower Sand and Gravel
unit may cause entrainment of fine silt and clay particles, which could plug the gravel pack and well screen,
or ultimately plug the pump intake and column pipe. Golder's design includes several features to reduce
the potential for and frequency of plugging, but periodic well redevelopment is expected to be required.
Design features to reduce plugging include using a 6 inch diameter well instead of a 4 inch well. The larger
diameter well provides for lower flow velocity through the filter pack that reduces turbulence and results in
less fine grained particles being carried towards the wells and potentially plugging the filter pack. In
addition, the well screen will be a stainless steel wedge wire screen which is designed to resist corrosion
and to hold the filter pack material back while maximizing the percent open area of the screen, further
reducing screen entrance velocities and potential plugging. The design also specifies a variable-frequency
pump which can maintain constant flow velocity into the well as opposed to cyclic pumping (where a fixed
flow rate pump turns on and off in response to water elevation), thus reducing the potential for over pumping
which can increase plugging from sediment transport into the gravel pack or well screen. Lastly, the design
includes placing the pump's intake above the screen to reduce the potential to draw the water level down
too low which could expose the screen to air which, in turn, could generate biological growth (e.g. iron
fouling).
The well redevelopment process itself involves pulling the pump out of the well, wire brushing the pump
screen, and cleaning the filter pack and well screen. The cleaning process will depend on what the nature
of the plugging is found to be and typically includes surge block development and airlift pumping
(mechanically pushing water in and out of the well screen then removing particulates via pumping).
Depending on conditions observed during cleaning, additional development techniques employed may
include high pressure jetting, impulse generation using nitrogen bursts (i.e., Hydropuls®), and possibly
chemical (biocide or acid) development techniques (if biofouling is observed).
The frequency of required well redevelopment is difficult to predict. Golder’s experience in public water
supply wells suggests it can range from 3 to 10 years in shallow gravel-packed wells, and from 10 to 30
years in deep sand aquifers. Contaminant recovery well systems typically require redevelopment every 1
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to 3 years. For the Newport well system, Golder estimates a required redevelopment frequency between
3 to 10 years. The longer frequency is possible considering that steady water levels should prevail using
the variable-frequency pump, the wells are moderately deep, and the pumping water levels will remain
above the well screen.
6.2.1 Extraction Well Design Based on the groundwater modeling results and stability analyses, a design pumping rate per well of 6.0
gpm is required to maintain sufficient depressurization in the Lower Sands and Gravels to reduce movement
of the landslide, provide a satisfactory global stability factor of safety, and provide redundancy and resiliency
in the pumping system. Stability analyses indicate all three wells operating at a lower steady state flow of
4.5 gpm results in a calculated FS of 1.32 for the deep-seated slide mass. All three wells pumping at 6.0
gpm results in a calculated FS of 1.40. If one well shuts down leaving two wells pumping at 6.0 gpm, the
calculated FS is 1.25. Analyses also indicate that if two wells shut down leaving the last well pumping at
6.0 gpm, the calculated FS reduces to 1.12. Considering these scenarios, Golder concluded that a design
pumping rate of 6.0 gpm was appropriate along with a minimum long-term pumping rate of 4.5 gpm.
It is important that the extraction wells be designed to operate as efficiently as possible to sustain these
pumping rates. Well efficiency is the measure of the theoretical drawdown in a well from laminar-flow losses
divided by the measured total drawdown in the well, which includes head losses from turbulent flow
generated as groundwater enters the well screen and gravel pack. The available drawdown in the well may
be a limiting factor on the pumping rates that can be achieved and maintained if the wells have an initially
low efficiency or if the efficiency deteriorates over time. Poorly designed and constructed wells and wells
that become plugged over time will typically generate greater turbulent head losses and therefore will have
a lower well efficiency. For example, the well efficiency of PTWa at the end of the 24-hour test is estimated
to have been 34%. This is derived by dividing the calculated theoretical drawdown of 30 ft by the measured
drawdown within the well at the end of the test of 87.5 ft. The theoretical drawdown was estimated using
the Theis non-equilibrium equation and the parameters derived from the 2013 pumping test.
During the 2013 test, the pumping water level in the PTWa drew down to within less than 10 ft above the
top of the screen, suggesting that this pumping rate in PTWa is not sustainable primarily due to the low
efficiency of the well. Therefore, it is important that the new extraction wells be drilled, constructed, and
developed in a manner to produce highly efficient wells. In addition, the wells should be placed on a regular
pump and well rehabilitation schedule to maintain high well and system efficiencies so that the minimum
pumping rate of 4.5 gpm from all three proposed wells can be achieved. Table 5 below provides a summary
of final design well construction and projected pumping water levels under anticipated well efficiency and
well interference conditions.
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Table 5. Well Construction Details and Projected Pumping Water Levels
Well AW-1 Well AW-2 Well AW-3 Well PTWa Ground Elevation (ft amsl) 782 793 802 792 Well Depth1 (ft bgs) 146 154 180 171 Well Diameter (in) 6 6 6 4 Water Table2 (ft bgs) 22 33 42 32 Top of Screen (ft bgs) 121 129 155 135 Bottom of Screen (ft bgs) 141 149 175 140 Pump Intake3 (ft bgs) 111 119 145 125 Available Drawdown4 (ft) 89 86 103 93 Predicted Drawdown5 (ft) 42 42 42 42 Predicted Well Losses6 (ft) 13 13 13 13 Predicted Interference7 (ft) 21 24 21 25 Total Projected Drawdown (ft) 76 79 76 80 Projected Water Level above Pump8 (ft) 13 7 27 13
Notes: Elevation given in feet above mean sea level (ft amsl); depth is given in feet below ground surface (ft bgs)
1. Well depth is 5 ft below the bottom of the screen to allow for a sump to collect sediment. 2. Water table elevation is assumed to be approximately 760 ft amsl based on PTWa hydrogeologic testing. 3. The pump intake is placed 10 ft above the top of the well screen to improve long-term well operations. 4. Available drawdown is calculated by subtracting the depth to water from the pump intake depth. 5. The predicted drawdown is estimated using the Theis non-equilibrium equation and assuming a transmissivity
of 42.8 ft2/day, a storage coefficient of 4.5E-04, a continuous pumping rate of 6 gpm, and a pumping duration of one year.
6. The predicted well losses assume a well efficiency of 70% and are estimated by multiplying 42 ft by 0.30. 7. The predicted drawdown interference is estimated using the Theis non-equilibrium equation and the distances
between each well. For PTWa, the estimate assumes that well AW-2 is off. 8. The projected water level above the pump is calculated by subtracting the projected drawdown from the
available drawdown.
There is some uncertainty related to the desired screen interval for the design of extraction well AW-3 due
to the lack of subsurface information in the area of this well as noted in the stratigraphic cross section shown
on Figure 5. Boring B-202 (drilled by VTrans in 2008) is the only boring previously drilled in the area of
proposed well AW-3 and it was terminated at El. 662, above the Lower Sand and Gravel strata where the
AW-3 well screen is proposed to be located. Golder recommends advancing an additional boring in the
vicinity of AW-3 to further characterize the soil strata below El 662 and confirm the planned well design is
appropriate for this location. Golder also believes the addition of a piezometer at this location would benefit
our understanding of the deep well system performance in this site area after installation. The findings from
the additional boring and conclusions regarding the well AW-3 design would be summarized in a letter
report.
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6.2.2 Well Screen Filter Pack As part of the 2013 investigation, grain size analyses were completed for five (5) formation samples from
monitoring wells B-204 (130-131 ft bgs, 135-136.5 ft bgs, and 140-141 ft bgs), B-305 (165-170.5 ft bgs),
and B-306 (140-152 ft bgs) following AASHTO Standards R58 and T882. These data were used to help
select the appropriate size of the screen openings and the surrounding filter sand pack. These sieve
samples were collected from the Lower Sand and Gravel unit.
Analyses indicate that the formation is comprised primarily of silt and clay size particles. Most of the
samples with the exception of B-204 (130-131 ft bgs) consisted primarily of silt and clay with 60 to 92
percent of the samples finer than the No. 200 sieve (0.075 mm) and a median (50% passing) grain size of
0.04 mm. B-204 (130-131 ft bgs) consists primarily of sand with a median particle size of 1.16 mm (coarse
sand) and only 8% silt passing the 200 sieve. The grain-size distribution data and graphs of cumulative
percent retained versus grain size for the samples used for extraction well design are provided in Appendix
B-2. Typically, a sand filter for a well screen is sized to be 4 to 6 times the 30% and 50% finer particle size
(D30 and D50) of the surrounding formation. In this case, the filter pack would be too fine-grained and
restrictive to the flow of water into the well if it were based on the D30 silt/clay particle size of most of the
samples. If an overly fine grained filter pack is used the resulting decrease in well yield could jeopardize
the groundwater pressure reduction objectives of the deep well extraction system. Therefore, we have
based our filter pack design on the coarsest sample from B-204, i.e. - 130-131 ft bgs. To help form a natural
filter within the native formation soils surrounding the well screen we recommend that the extraction wells
be aggressively developed with pumping and surging during installation. With this procedure we expect
that the amount of any fine grained silt or clay sized particles that penetrate through the filter pack will be
minor and should not affect pump performance.
Golder used standard well filter pack design standards to select the filter pack and screen size 14,15. Criteria
for standard filter pack design includes evaluation of the soil sample particle gradation, selection of the D60,
D30 and D10 particle sizes, selection of the filter/gravel pack ratio (GPR) based on the uniformity coefficient
(Cu), selection of the filter pack particle size; and selection of the well screen slot size. The procedure
includes the following:
1) Plot the grain size distribution of the formation materials on a percent retained basis.
2) Establish the D60, D50 and D10 passing grain size values of the formation, and the D10 passing grain size value for the filter pack.
3) Establish the uniformity coefficient (Cu = D60/D10 [dim]) of the formation.
4) Choose a gravel pack ratio (GPR) based on Cu (GPR=4 if Cu<3; GPR=5 if Cu is 4-5; and GPR=6 if Cu>6).
14 Williams, E.B., 1981. Fundamental Concepts of Well Design. Ground Water, Vol. 19, No. 5, September-October, p. 527-542. 15 Driscoll, F.G., 1986. Groundwater and Wells (2nd ed.), Johnson Filtration Systems, Inc., St. Paul, Minnesota, 1089 p.
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5) Choose gravel pack based on the formation D30, and D50 x GPR to establish the D30 of the filter pack.
6) Choose a uniform filter pack gradation that passes through the established D30 filter pack point, and has a Cu < 2, preferably around 1.5.
7) Select screen slot size to retain 90 – 95% of the filter pack, corresponding to the D10 – D5 passing grain size.
8) Confirm approach, entrance and uphole velocities meet standard well design criteria.
Based on the B-204 130-131 ft bgs sample, the filter pack should have a D30 grain size of approximately
0.64 mm assuming a GPR of 6. This equates approximately to a #0 filter sand manufactured by U.S. Silica
Filpro®. A screen with 0.020-inch slot openings was selected to retain 95-100% of the Filpro #0 filter pack
as shown below in Figure 6. The other four samples of formation material are considered too fine grained
for conventional well design parameters to be applied effectively for this system. Accordingly, the final filter
pack design is based on Golder’s best judgement considering our interpretation of the subsurface
conditions and the objectives of the well system.
Figure 6 - Selection of Filter Pack and Well Screen Slot Size
6.2.3 Entrance, Approach and Uphole Velocity Estimates Golder recommends that high-efficiency, 6-inch diameter stainless steel (Type 304), continuous wire-
wrapped water well screens be used for the extraction wells. The stainless steel provides greater long-
0
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0.01 0.1 1
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Grain Size (inches)
GRAIN SIZE DISTRIBUTION FOR US Silica FilPro# 00 FilPro #0 FilPro # 1 FilPro# 2 FilPro # 3 FilPro B-204 130-131', GPR=6B-204 130-131'
Choose 20 Slot Screen
Choose Filpro #0
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term resistance to electrochemical corrosion. These well screens provide a large percentage of open area
decreasing entrance velocities. The large diameter of the screen and surrounding filter pack decreases
approach and entrance velocities of radial groundwater flow towards the gravel pack and well screen.
Lower approach and entrance velocities reduces turbulent flow losses and will reduce the potential plugging
of the filter pack and well screen from mineral precipitation, iron bacteria encrustation, and entrainment of
fine silt and clay particles from the surrounding formation. These well design measures will increase the
efficiency of the well and will decrease long-term well maintenance and rehabilitation costs. The 6-inch
well casing diameter also accommodates a 4-inch diameter submersible pumps.
The calculated open area of the screen with 0.020-inch slot openings is 40 square inches per linear foot
(in2/ft), equating to a percent open area of 16%. The average entrance velocity of water moving into the
well screen should not exceed 0.1 feet per second (ft/sec). At this velocity, the amount of turbulent flow
and friction losses through the screen opening will be negligible and the rates of sediment plugging, mineral
incrustation and corrosion will be minimal. The calculated entrance velocity for these wells at the design
pumping rate of 6 gpm is 0.0024 ft/sec. The well should also be designed to limit the approach velocity into
the surrounding gravel pack to 0.02 ft/sec. The calculated approach velocity in this case is 0.0003 ft/sec.
Lastly, the uphole velocity inside the screen and well casing should be less than 5 ft/sec. In this case, the
estimated uphole velocity is 0.07 ft/sec. Well design criteria are summarized in Table 6.
Table 6. Well Screen Design Criteria
Well Design Parameter Design Limit Actual
Screen Open Area - 40 in2/ft Screen Open Area - 16% Screen Transmitting Capacity - 12.45 gpm/ft Entrance Velocity 0.1 ft/sec 0.0024 ft/sec Approach Velocity 0.02 ft/sec 0.0003 ft/sec Uphole Velocity 5 ft/sec 0.07 ft/sec
6.2.4 Pump and Pump Controls The pump intake will be set at a maximum depth of 10 feet above the top of the well screen. This will
reduce the potential introduction of oxygen into the well screen which may promote bacteria growth and
formation of iron bacteria, and will reduce turbulent flow and degassing of carbon dioxide which may
promote mineralization including the precipitation of calcium carbonate and iron oxyhydroxides. For the
purpose of conservatively estimating the total dynamic head (TDH) for each well, the depth of pump intake
is used to calculate friction losses in the pump column pipe and the vertical head of the system. Friction
losses are relatively minimal within high-density polyethylene (HDPE) pipe and pipeline components (e.g.,
flow meter, check valves, gate valves, pipe elbows, etc.) primarily due to the low design flow from the wells.
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However, friction losses are excessive when it is assumed that 50% of the initially evaluated 1.25-inch
diameter HDPE pump column pipe and the 2-inch diameter HDPE distribution pipeline are plugged by iron
bacteria and mineral encrustation. For this reason, the pipeline diameters were increased to 2-inch for the
column pipe and 3-inch for the distribution pipe. Well AW-3 has the greatest TDH primarily due to its deeper
screen and pump intake setting. The estimated TDH for AW-3 is 149 feet at a maximum pumping rate of
10 gpm. If it is assumed that the column pipe and pipeline are 50% blocked, then the maximum design
TDH is 174 feet. Table 7 summarizes the static and dynamic head calculations for all four wells. TDH
worksheets are provided as Appendix D.
Table 7. Estimated Total Dynamic Head (TDH) and Pump Design Parameters
AW-1 AW-2 AW-3 PTWa Design
Maximum Friction Losses (feet) 2 2 1 2 28 Vertical Head (feet) 134 131 148 138 146 TDH (feet) 136 133 149 140 174 Pumping Rate (gpm) 10 10 10 10 10 Minimum Horsepower (hp) 0.5 0.5 0.6 0.5 0.7
Based on these head and flow requirements, a Goulds Model 10GS07 electric submersible pump with a
0.75 horsepower motor was selected for the extraction wells. This pump has seven stages and is rated at
13.4 gpm at a TDH of 180 feet. The actual flow from the well will depend on the level of water in the well
and friction losses throughout the distribution system. The manufacturer’s pump curve and performance
specifications are provided in Appendix E.
The pump will be controlled using Goulds’ Smart Pump Technology system, which uses a variable speed
drive and pressure transducer to maintain a relatively constant water level in each well. This control system
will protect the pump and the well from over pumping while allowing pumping rates to be automatically
adjusted to maintain a minimum water level in the well. The controls will be housed in an onsite concrete
building as shown on Figure 3. All piping will remain below the 72-inch frost depth. Wireless communication
will allow remote monitoring on a web-based application.
Golder’s final extraction system design components are included in Sheets 61 – 65 of Stantec’s preliminary
plans8. These include:
Extracted groundwater piping plan and profile
Extraction well details
Extraction system trench and flow meter vault details
Pump house building plan, elevations and details
Piping and instrumentation plan
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A draft Special Provision for the Groundwater Deep Well Pumping System materials, installation,
submittals, and method of measurement is included in Appendix F.
6.3 Upper Embankment Slope Stabilization The stability of upper embankment slope areas between Stations 116+00 and 119+00 (see Figure 2) was
assessed using soil profiles, soil strength parameters and groundwater conditions developed based on the
information presented in our 20146 report and confirmed by the DCP testing conducted in 2017. Where the
analyses indicated marginal stability conditions, analyses of stabilization alternatives were performed to
provide the most efficient methods for stabilization. A detailed summary of our stabilization alternatives
analyses were summarized in our 20157 letter report. The chosen stabilization method was slope flattening
and improved drainage and is described as Alternative US-2 in the report. The area of stabilization is
shown on Figure 3 and is shown on sheets 6, 29, 38, and 90 to 93 of Stantec’s preliminary plans8.
6.3.1 Slope Flattening The selected stabilization alternative includes flattening the embankment slope above the stability berm
with a controlled structural fill. The western part of the embankment appears to be over steepened relative
to the rest of the embankment. Existing slopes in this western slope area vary between about 1.4H:1V to
1.9H:1V. Within the area planned for upper slope stabilization shown on Figure 3 additional engineered fill
is planned to be placed to flatten the final grade to a 2.1H:1V slope. The existing topsoil should be stripped
prior to regrading activities and the new fill benched into the existing slope. The new fill material should
conform to the gradation requirements outlined in VTrans specification 704.18 (i.e., the electrochemical
requirements are not necessary for this application), Select Backfill for Mechanically Stabilized Earth (MSE)
Walls, and be compacted to 95 percent of modified proctor as detailed in 900.608 Special Provision (Select
Backfill) a copy of which is provided in Appendix F. Refer to “Upper Slope Mitigation Profile” detail on sheet
6 of Stantec’s preliminary plans8. The slope flattening should be constructed after the installation of the toe
drain.
6.3.2 Toe Drain In conjunction with slope flattening, the final design for upper slope stabilization includes the installation of
a toe drain along the stability berm. The existing western portion of the stability berm below the upper slope
slide is overgrown with vegetation indicating a shallow water table. During Golder’s previous site
investigations, this area has also been observed to be wetter than other areas of the stability berm. The
elevated water table in this area is believed to partially contribute to the current slide in the upper slope.
The intent of the toe trench drain is to lower the groundwater table at the toe of slope and increase the
stability of the upper slope. The proposed toe drain should include a 6 inch diameter HDPE underdrain
pipe founded approximately 8 ft below the existing stability berm ground surface at the toe of the slope, and
installed at the grades shown on sheet 38 of Stantec’s preliminary plans8 to allow for the drain to daylight.
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The toe drain trench should be lined with geotextile for underdrain trench lining and backfilled with peastone
or crushed stone conforming to VTrans specification 704.16, Drainage Aggregate to promote drainage
through the trench, as shown in the “Toe Drain Detail” on sheet 68. Since the toe drain will be buried in the
new embankment fill for the flatted upper slope, it should be installed prior to the slope fill.
Excavation of a trench across the toe of an already unstable slope could cause further slope instability.
Methods to prevent the movement of the slope into the open trench will be required of the contractor.
Temporary shoring that is in intimate contact with the trench walls, such as a slide-rail type shoring system,
could be acceptable while the use of standard trench boxes that are narrower than the excavated trench
should not be allowed as they will not prevent slope movement. Care will also be required to limit the depth
of trench excavation support systems to the bottom of the toe drain trench elevation to avoid damaging
underlying existing horizontal drains as discussed in Section 6.3.3. We recommend that the length of open
and unsupported toe drain trench be limited to 25 ft during toe drain excavation and installation. This will
require the contractor to work in short segments or work continuously with excavation and backfilling
occurring simultaneously.
6.3.3 Existing Drainage Systems in Stability Berm Area Two previously installed drainage systems are present in the stability berm area as shown on Figure 2 and
may be encountered during the planned mitigation construction. The existing drains include: 1) a series of
parallel 2-inch PVC horizontal drains installed in a northeasterly orientation; and 2) 6 inch corrugated HDPE
underdrains installed in an east-west orientation along nearly the full length of the stability berm. Both
drainage system are currently active and providing a positive effect on embankment stability, and should
be repaired in place if encountered during construction.
The horizontal drains were initially installed in 1971 shortly after construction of the embankment fill and
were extended in 1991 during the construction of the stability berm. These drains run from under the upper
slope and daylight at the base of the stability berm and are constructed out of solid 2-inch PVC pipe. The
approximate locations of these drains are shown on sheets 28 and 29 of Stantec’s preliminary plans8, but
construction records of these drains are approximate and may vary from the locations shown in the design
drawings. The proposed orientation of the toe drain is located across (transverse to) the alignment of the
horizontal drains. Based on our interpretation of the drain elevations shown in Figure 7, we anticipate the
bottom of the toe drain trench will be above the horizontal drains, but the interpreted separation distance is
small, less than 24 inches at horizontal drain numbers HD-3 and HD-13. Since the actual horizontal drain
locations and elevations are uncertain the contractor should take extra caution when excavating the toe
drain trench. Should any horizontal drains be intercepted during construction of the toe drain, the drain
should be repaired using like material to maintain drainage and serviceability of the drain through the
original outlet.
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The 6” corrugated HDPE underdrains shown on Figure 2 were installed with the stability berm as shown on
sheets 9 and 11 in the 1991 construction plans16. While these plans show the approximate horizontal
locations of these drains, no information is available regarding the drain elevations. Construction of the
proposed toe drain and/or the extraction well discharge header pipe may intercept one or two of these
existing underdrains. Flushing basins for the drain that outlets in the center of the berm at approximately
Station 116+25 are visible on both ends of the stability berm. The flushing basin on the west end is
approximately at Station 119+00, 100 ft right. If this drain is intercepted it should be repaired using like
materials such that it maintains drainage. If drainage is unable to be maintained due to the location of the
new toe drain, the existing drain should be cut short and a new flushing basing installed. A second
underdrain was installed along the existing slope during construction of the stability berm and outlets at
approximately Station 119+00, 119 ft right. This drain runs approximately parallel to the proposed new toe
drain. If this drain is intercepted during construction it should be repaired using like materials such that
drainage is maintained. If drainage cannot be maintained due to the location of the new trench drain, the
existing drain should be spliced into the new drain using a “Y” fitting. As noted in Section 7.2, a pay item
should be included in the contract documents for drain repair to address these concerns.
6.4 Headscarp Seal Long term displacements of the deep-seated slide mass along the slide plane described in Golder’s 2015
letter report7 provide a potentially preferential pathway for surface runoff and groundwater to travel from the
ground surface and/or surficial soil strata to the Lower Sand and Gravel unit. Reducing the ability for surface
water in the area of the headscarp to replenish the groundwater at depth will increase the efficiency of the
extraction wells at depressurizing the Lower Sand and Gravel unit and improve stability. Additionally, as
noted in the groundwater analysis10, the potential presence of deicing compounds in one of the wells
suggests that surface water may currently be migrating down the failure scarp and entering the Lower Sand
and Gravel unit.
Golder assessed options for sealing the headscarp. The asphalt pavement of the Route 191 roadway seals
the headscarp in the areas where the scarp crosses the road and needs no further treatment. The area
uphill (south) of Route 191 has experienced deformation from the movement of the slide and currently
allows surface water to pond on the headscarp area in several locations. Sealing the headscarp area uphill
of Route 191 with either a layer of low permeability clay or a geomembrane liner material (HDPE or PVC)
were considered. Headscarp areas downhill (north) of Route 191, roughly from Sta. 110+00 to 112+00 are
planned to be regraded and resurfaced as part of the proposed new access road construction. Considering
the regraded final slopes in these areas and related reduced potential for runoff infiltration, as well as the
16 VTrans (1991). Drawings titled “Proposed Improvement, Town of Newport, County of Orleans, VT Route 191 (F.A.P.)”, State of Vermont, Agency of Transportation, Project Derby-Newport F 134-3(17) C/I, May 9, 1991, with edits as record plans, dated April 24, 1992.
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drainage improvements planned for the Route 191 roadway reconstruction, we do not believe additional
headscarp sealing in this area is warranted.
The clay seal option has the advantage of lower installation and construction QA/QC cost, however, suitable
clay borrow materials are not available in the Newport region and substantial hauling costs were concluded
to render this option economically impractical. Accordingly, a 30 mil geomembrane liner is recommended
to seal the headscarp south of Route 191, including the area between the edge of pavement and the existing
underdrain located along the south side of the roadway as shown on Figure 3. The intent of lining this area
is to collect and properly discharge rainfall and snowmelt occurring over the headscarp area as well as to
prevent surface water runoff from the roadway from seeping into the headscarp void. We recommend a
high-density polyethylene (HDPE) or polyvinyl chloride (PVC) geomembrane be selected for this
application. HDPE is commonly used for landfill liner and cover systems, and VTrans has experience with
PVC geomembranes for MSE wall applications. The geomembrane should be placed over a 6-inch “lower”
sand cushion to protect it from punctures from deleterious materials in the subgrade soils. A 9-inch “upper”
sand cushion should be placed above the geomembrane to provide protection and a drainage media to
convey surface water infiltration to an underdrain pipe. A minimum of 9 inches of overlying fill and topsoil
should be placed to maintain the geomembrane at least 18 inches below ground surface. A recommended
headscarp seal section and geomembrane tie-in underdrain detail is shown on Figure 8. A Special
Provision for geomembrane and sand cushion materials, installation, QA/QC, submittals and basis of
payment is provided in Appendix F.
During headscarp sealing construction a portion of the existing corrugated metal underdrain in this area will
need to be relocated to the south boundary of the geomembrane liner as shown on Figure 3. The condition
of the existing underdrain pipe and suitability for reuse could be evaluated during construction: however,
as discussed in Section 7.2 we recommend that this entire section of underdrain be replaced with new pipe
due to the age of the existing pipe.
Additional underdrain in the area of the headscarp seal, approximately 10 ft off the edge of pavement and
running parallel to Route 191, is shown on the 1991 stability berm construction plans16.and on Figure 2.
We believe these are 6 inch corrugated HDPE underdrains. If these underdrains are encountered during
construction they should be repaired in place or spliced into the recommended replacement 8-inch
underdrain system using a “Y” fitting. As noted in Section 7.2, a pay item should be included in the contract
documents for drain repair to address these concerns.
6.5 Cutoff Trench Drain Observations made in 2012 and 2013 on site indicate that vegetation growing on the sides of the existing
embankment in the area of the 30-inch culvert is consistent with the presence of shallow groundwater within
the embankment. We assume that groundwater flowing down the roadway alignment to the northwest in
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the pavement subbase and subgrade is intercepted by the culvert backfill material from the 1996 culvert
repair and daylights on the slope of the embankment.
To further reduce the amount of groundwater available in the area of the headscarp and embankment slide,
a cutoff trench drain extending across the width of Route 191 should be installed on the east end of the
project in the vicinity of Station 109+00 as shown on Figure 3. The cut-off trench drain should consist of a
6 inch perforated underdrain pipe located in a geotextile lined trench a least 30 inches wide and filled with
Drainage Aggregate meeting the requirements of VTrans 704.16. The underdrain pipe invert should be
located at least 5 ft below the pavement surface of the reconstructed roadway, which should locate the
invert at least 4 in. below the base of the Sand Borrow layer in the planned pavement section shown on
sheet 4 of Stantec’s preliminary plans8. Based on the existing grading, it is anticipated that the cut-off
trench drain pipe should drain towards the southwest and tie into the existing roadside underdrain on the
uphill side of the road.
6.6 Access Road Stability Following discussions with Stantec and a review of the access road alignment proposed in the VTrans
conceptual phase drawings dated August 4, 2016, Golder recommended that the project team consider
alternative access road alignments to reduce the volume of fill being placed on the side slopes of the
existing Route 191 embankment. The project team then proposed a revised access road alignment (shown
on Figure 3) with less fill than presented in the conceptual plan set and Golder proceeded with the
exploration program described in Section 2.2 in support of a slope stability analysis for the revised access
road configuration.
6.6.1 Stability Analysis Global stability was evaluated for transverse sections through the Route 191 embankment at revised
access road stations 53+00 and 54+00 using the computer model Slide17. These stations were selected
as they represent the sections where the construction of the proposed access road will result in the
placement of fill on the existing Route 191 embankment (53+00) and removal of material from the existing
embankment slope (54+00). Subsurface conditions used in the models were interpreted based on the soil
stratigraphy and ground water conditions encountered during our 2017 exploration program and soil
properties corresponding to STP blow counts in the borings, DCP testing and direct shear testing performed
on reconstituted soil samples. Results of the direct shear tests were further tempered with the results of
historic direct shear testing conducted on embankment material in 2013. An analysis of interpreted existing
conditions at these sections indicated the existing Route 191 embankment has a calculated factor of safety
(FS) of about 1.2.
17 Rocscience, Inc. (2017). Slide – 2D Limit Equilibrium Slope Stability and Groundwater Analysis for Rock and Soil, Version 7.024, build date May 4, 2017, Toronto, Ontario, Canada.
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Following construction of the proposed access road, the FS at station 53+00 is calculated to be 1.4. This
increase in FS from the existing conditions is the result of fill being placed on the embankment which
provides a stabilizing force helping to prevent sliding. The FS at section 54+00 is not impacted by
construction of the new access road.
Our analysis of the impacts of the access road construction was limited to the Route 191 embankment and
a detailed analysis of the lower stability berm was not conducted due to the lack of detailed soil and ground
water information in that area. However, based on field observations there is no evidence of instability
along the lower stability berm and Golder believes that factors of safety will increase once the improvements
recommended in this report are completed.
Assumed geometries, configurations, subsurface conditions, and stability analyses results are presented
in Appendix G.
6.6.2 Stabilization Provisions Local slope stability in the area of the new access road appears to be improved by the construction of the
access road and the associated addition of fill placed on the embankment slope. The use of the extraction
wells increases the FS of the larger slide to the degree that a minimal amount of additional load at the head
of the slide, such as fill placed for construction of the access road, is acceptable. However, such fill should
be kept to the minimum necessary and no wasting of excavation material in this area should be permitted.
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7.0 CONSTRUCTION AND POST-CONSTRUCTION CONSIDERATIONS To ensure the successful construction and implementation of the slope stabilization provisions outlined in
this geotechnical design report, Golder recommends the following construction considerations be
incorporated into the contract documents.
7.1 Deep-Seated Slide Extraction Well Construction Considerations A hydrogeologist should be present full-time during extraction well drilling & installation to
log the holes & well construction, confirm anticipated conditions, select ultimate screen locations/depths, observe pumping tests, and collect water levels.
A water-systems type engineer should be present during the extraction system construction & commissioning to help troubleshoot items, assist the contractor, and make field changes to the design as needed. In our experience, the availability of such an engineer greatly adds to the success of the project.
7.2 Upper Embankment Slope and General Site Construction Considerations New fill material should be placed on embankment side slopes after the slope has been
benched and prepared accordance with VTrans standard drawing B-5.
The final design for upper slope stabilization includes the installation of a toe drain along the stability berm. Construction considerations for the sequencing and bracing of the toe drain excavation are discussed in Section 6.3.2 and should be highlighted in the contract documents.
Additional fill placed onto the stability berm, the embankment slopes, and the area of Route 191 between the headscarps is effectively loading the deep-seated landslide. Stockpiling of material should not be allowed in these areas, and placement of fill greater than the limits shown on the contract documents should also not be allowed.
The contract documents should include a pay item for drain repair to include the repair of existing 2 inch PVC horizontal drains and/or 6 inch corrugated HDPE drains if encountered and damaged during installation of the toe drain for the upper slope stabilization work, the discharge header pipe for the deep extraction well system, or the headscarp seal.
A geotechnical engineer should be present on site to confirm encountered conditions during culvert replacement, underdrain replacement, access road construction, embankment grading, and trenching. Additionally, the geotechnical engineer should be consulted during excavation of the toe drain for any interception and repair of horizontal drains and underdrains.
Due to the age of the existing corrugated metal underdrain pipe and to help limit shallow ground water and surface water infiltration into the ground on the south side of Route 191, Golder recommends the existing underdrain above the head scarp be replaced during this construction project as noted on Figure 3. Additionally, this drain would need to be incorporated into the head scarp seal (Section 6.4) and will be daylighted already during that work.
We recommend the underground telephone line shown at approximate station 111+00 on sheet 177 of 263 of the 1971 as-built plans18 be noted on the new construction drawings with a note stating it has been abandoned to avoid confusion during construction. The
18 State of Vermont, Department of Highways City of Newport, County of Orleans, Interstate Connection (1971). Sheet 177 of 263. Drawing titled “Stage 2 Construction, Derby-Newport F 341-5(4)”.
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depth that the line is buried beneath Route 191 is unknown. It is likely that the presence of this utility will not impact any planned work for this project.
7.3 Geotechnical Instrumentation Golder recommends maintaining the existing piezometers to monitor the performance of
the deep groundwater extraction system in addition to the pressure transducers that are being installed with the well pumps. All existing cables, conduits and data loggers should be protected during construction to ensure full functionality at the conclusion of the project. Golder personnel should be on site to verify equipment operation after construction. The full instrumentation system needs to be operable prior to commissioning of the deep extraction wells to log the groundwater response to the initial startup of the well pumps.
We recommend VTrans continue to monitor slope performance with the SAAs installed along the shoulder of Route 191 following the completion of construction. All existing cables, conduits and data loggers should be protected during construction to ensure full functionality at the conclusion of the project.
Monitoring of the two existing IPI arrays (B-306 and B-311) should be terminated and the arrays removed for beneficial reuse by VTrans. Golder should be on site during removal to ensure equipment is properly decommissioned for reuse. Both arrays were installed in standard inclinometer casing so the casings should remain for future monitoring (as needed) using a manual inclinometer probe.
The existing datalogger is located adjacent to B306 and has several sets of communication cables crossing the stability berm and running up the face of the embankment towards B305. At B305, the cables split in multiple directions. Two sets of cables run parallel to Route 191 to B318. One cable runs in a 1.5” PVC electrical conduit buried in a shallow trench under Route 191 towards B302. Two sets of cables run to B305 itself. The Contractor can be allowed to cut and temporarily remove communication cables as needed to allow for construction activities provided it is repaired with proper splices rated for underground work. The conduit running under Route 191 should be retained and the communication cable reinstalled as part of the reconstruction of the subbase.
As outlined in our January 27, 2017 proposal, Golder will be providing an instrumentation plan that is expected to include the continued monitoring of the previously installed vibrating wire piezometers and the two SAAs. The instrumentation plan will also address the impact of the proposed works on the main datalogger and solar panel associated communication wiring to the sensors, including sensors located across VT 191.
7.4 Post-Construction Groundwater Sampling and Analysis We recommend that VTrans perform post-construction groundwater sampling of extraction well discharge
water to document iron and manganese concentrations. In addition to iron and manganese testing, Golder
recommends testing the groundwater for standard field chemistry parameters including temperature, pH,
specific conductance, Eh/redox potential, dissolved oxygen, and salinity. A post-construction groundwater
sampling and analysis plan should be developed outlining a frequency for sampling, sampling requirements,
and groundwater analyses requirements.
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8.0 CLOSING AND LIMITATIONS The geotechnical information, test results, design recommendations, and construction considerations
included in this report are provided for the exclusive use of VTrans for development of final landslide
mitigation design for Route 191 in Newport, Vermont. This report was prepared in accordance with
generally accepted soil, foundation engineering and hydrogeologic practices conducted in this geographical
area and under similar financial and time constraints. Golder makes no other warranty, either express or
implied. In the event that any changes in the nature, design, or location of the proposed project are planned,
Golder should be notified to review the appropriateness of our conclusions and recommendations and to
modify the recommendations as appropriate to reflect the changes in design. Further, our analyses, and
recommendations are based in part on the subsurface explorations completed. Golder should be notified
if conditions encountered during construction vary from those described in this report so that we may re-
evaluate, and if necessary, revise the recommendations made in this report.
The professional services provided by Golder for this project included only the geotechnical and
hydrogeologic aspects of the subsurface conditions at this site. The presence or implications of possible
surface and/or subsurface contamination resulting from previous activities or uses of the site and/or
resulting from the introduction onto the site of materials from off-site sources are outside the terms of
reference for this report and have not been investigated or addressed.
TABLES
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Date
1969-1971
1971
1973
1974
1971-1976
1986
1989
1991
1996
1996-2011
2006-2009
2006-2011
2011
2012
2013
2013 - current
2014
2015-2016
2016-2017
2017
Stantec preliminary design of VT Route 191 improvements including civil design support for deep and shallow fill embankment stabilization systems.
Golder investigation of stability of proposed access road to extraction well site area, final design of deep extraction well stabilization system, final design of upper slope stabilization, final design of headscarp seal.
Golder remote & on-site monitoring of precipitation, piezometric heads and slope movements
VTrans evaluations of stability and mitigation alternatives presented at ASCE conference3. Groundwater lowering identified as preferred mitigation alternative
Inclinometer data indicates base of slide mass located up to 120 ft below ground surface (bgs) at counterbalancing berm and extends to base of slope near Clyde River
Sinkhole developed at 30-inch diameter culvert due to 8 ft of vertical separation. Culvert was replaced.
Golder geologic, hydrogeologic and geotechnical subsurface investigation, remote instrumentation installation, and detailed geotechnical laboratory testing.
Inspection of 30-inch diameter culvert indicates additional deformation.
Golder deep slide mitigation alternatives study and preliminary design, upper slope stabilization preliminary design, headscarp seal preliminary design
Golder Geotechnical Data Report (August)
Numerous pavement leveling operations. Culvert location still experiencing significant deformation.
VTrans subsurface investigations including additional borings, instrumentation, laboratory testing and a culvert inspection survey. Culvert deformation measured at about 8 inches.
1.5 ft of settlement measured since 1971 construction (average of 6 in/yr).
Roadway pavement settlements average 4 inches per year
Operations removed 4 ft of pavement (average = 3.2 in/yr for 15 year period 1971-1986).
VTrans subsurface investigation, evaluation and report2. Failure surface identified about 10 to 25 ft below original ground surface beneath embankment fill.
Counterberm construction and more horizontal drains added.
Table 1: Chronology of Key Project Events Geotechnical Design Report VT Route 191 Embankment Slide Newport, Vermont
Event Description
Original embankment construction
April: first sign of slope movement; 5 inches of separation at 30-inch diameter culvert traversing beneath roadway within embankment fill. June: installed underdrain system at toe of upslope embankment slope.
Installed 17 horizontal drains
P:\Projects\2016\1668897 VTrans Newport Supplemental Design\700 Reports\Final Report\Tables\Tbl 1 Chronology.xlsx
November 2017 Page 1 of 1 Project No.: 1668897
Table 2:
Station Offset Upper Lower
111 + 40 17.2' RT 854 52.0 1.5 30 10 40 25 03/20/17 Silt and Silty Sand
111 + 40 103' RT 820 32.0
109 + 18 55' RT 862 32.0
Notes: 1.2.3.4.5. Prepared By: LLM6. Checked By: CJS
Reviewed By: CCB
Geotechnical Boring and Piezometer Summary Geotechnical Design Report VT Route 191 Embankment Slide Newport, Vermont
Test boring locations are shown in Figure 3 "2017 Boring Location Map and Final Design Elements."
B-401
B-402
B-403
Test Boring Designation1,2
As-Drilled Locations3Existing
Ground SurfaceElevation4
(ft)
Boring Depth5
(ft bgs)
Piezometer Installation Information
Screen Interval
(ft bgs)5
Nominal
PVC Casing
Diameter
(in)
Screen
Length
(ft)
Boring logs and piezometer logs presented in Appendix A.
All borings were performed by VTrans in March, 2016.As-drilled locations from field measurements.As-drilled elevations are derived from topographic map shown in Figure 3. Depth below ground surface.
Piezometer Not Installed
Piezometer Not Installed
Midpoint
Depth
(ft bgs)
Installation
Date
(mm/dd/yr)
Well and
Piezometer Screen
Location
P:\Projects\2016\1668897 VTrans Newport Supplemental Design\700 Reports\Final Report\Tables\Tbl 2 Borings.xlsx
November 2017 1 Project No.1668897
Table 3:
Exploration ID Location(1) BlowsPenetration
(mm)
DCP Penetration
Index (mm/blow)
Cumulative
Penetration (ft)
Calculated SPT
N Value(2)
Average Calculated
SPT N Value(3) Assumed Phi Notes
2 188 94 0.62 102 92 46 0.92 142 197 99 1.56 102 70 35 1.79 162 95 48 2.11 142 56 28 2.29 182 83 42 2.56 155 48 10 0.16 305 24 5 0.24 435 25 5 0.32 425 10 2 0.35 661 1 1 0.35 932 9 4 0.38 441 164 164 0.54 82 71 36 0.77 16
2 32 16 0.88 242 29 15 0.97 252 24 12 1.05 272 11 6 1.09 405 20 4 1.15 475 22 4 1.22 455 11 2 1.26 63
10 10 1 1.29 9310 10 1 1.33 932 42 21 0.14 212 66 33 0.35 171 90 90 0.65 101 48 48 0.81 141 55 55 0.99 132 49 25 1.15 192 45 23 1.30 201 69 69 1.52 122 66 33 1.74 172 71 36 1.97 162 71 36 2.20 162 95 48 2.52 141 151 151 3.01 83 56 19 0.18 222 16 8 0.24 332 14 7 0.28 362 8 4 0.31 473 18 6 0.37 383 21 7 0.44 363 23 8 0.51 343 31 10 0.61 292 21 11 0.68 292 17 9 0.74 323 18 6 0.80 383 10 3 0.83 513 9 3 0.86 545 14 3 0.91 565 16 3 0.96 525 13 3 1.00 58
10 28 3 1.09 5610 37 4 1.21 4910 58 6 1.40 3910 57 6 1.59 3910 47 5 1.75 4310 43 4 1.89 4510 48 5 2.04 4310 63 6 2.25 3710 69 7 2.48 3610 89 9 2.77 32
16
53
18
58
15
39
47
37
35
35
35
35
35
-
- Drove through some shale
over first interval.
- Hole terminated for excessive
top deflection.(4)
- Snow on ground; frozen on
top.
- Not frozen very far into ground
(soft below surface)
- Off vertical at end of test; cone
hitting something hard, possible
rock.
-
Below
Proposed
Access Road
DCP-2
DCP-4
Below
Proposed
Access Road
-
13
17
Dynamic Cone Penetrometer Test Results Geotechnical Design Recommendation Report VT Route 191 Embankment Slide Newport, Vermont
DCP-3
Below
Proposed
Access Road
DCP-1
Below
Proposed
Access Road
12
13
Below
Proposed
Access Road
DCP-5
P:\Projects\2016\1668897 VTrans Newport Supplemental Design\700 Reports\Final Report\Tables\Tbl 3 DCP testing summary.xlsx
November 2017 2 Project No.1668897
Table 3:
Exploration ID Location(1) BlowsPenetration
(mm)
DCP Penetration
Index (mm/blow)
Cumulative
Penetration (ft)
Calculated SPT
N Value(2)
Average Calculated
SPT N Value(3) Assumed Phi Notes
35 -
Dynamic Cone Penetrometer Test Results Geotechnical Design Recommendation Report VT Route 191 Embankment Slide Newport, Vermont
DCP-1
Below
Proposed
Access Road
122 46 23 0.15 201 67 67 0.37 122 39 20 0.50 215 12 2 0.54 604 8 2 0.56 664 2 1 0.57 1305 5 1 0.59 935 7 1 0.61 795 1 0 0.61 2055 1 0 0.62 205
10 8 1 0.64 10310 2 0 0.65 20510 10 1 0.68 930 136 - - -1 112 112 0.81 95 46 9 0.96 312 78 39 1.22 151 64 64 1.43 121 79 79 1.69 111 90 90 1.98 101 92 92 2.29 101 71 71 2.52 111 64 64 2.73 121 56 56 2.91 132 41 21 0.13 212 17 9 0.19 323 25 8 0.27 333 36 12 0.39 273 132 44 0.82 141 171 171 1.38 71 44 44 1.53 143 62 21 1.73 212 66 33 1.95 172 104 52 0.34 132 29 15 0.44 255 37 7 0.56 353 48 16 0.72 245 57 11 0.90 285 211 42 1.59 155 79 16 1.85 245 32 6 1.96 375 46 9 2.11 315 49 10 2.27 305 41 8 2.40 335 41 8 2.54 335 35 7 2.65 365 42 8 2.79 322 51 26 0.17 19 19 352 304 152 1.16 8 82 256 128 2.00 81 57 57 2.19 131 63 63 2.40 121 109 109 2.76 92 242 121 0.79 9 91 89 89 1.09 101 46 46 1.24 142 50 25 1.40 192 74 37 1.64 162 69 35 1.87 162 60 30 2.07 172 79 40 2.33 151 55 55 2.51 13
15
11
15
99
12
12
25
15
25
25
30
30
35
35 -
-
- Snow on ground.
35
- Rod deflecting pretty far from
vertical towards the end of test .
35
32
35
32
35
DCP-11
DCP-10
Between
Proposed
Access Road
& Route
191
Between
Proposed
Access Road
& Route
191
DCP-8
Between
Proposed
Access Road
& Route
191
- Rod deflecting pretty far from
vertical towards the end of test.
- Rod sunk from 0.1' (3.3 cm) to
0.6' (16.9 cm) before first blow.
- Possible gravel between 1.0'
(32.7 cm) and 1.3' (40.5 cm)
penetration.
32
Between
Proposed
Access Road
& Route
191
DCP-7
20
Between
Proposed
Access Road
& Route
191
Between
Proposed
Access Road
& Route
191
DCP-9
DCP-6
P:\Projects\2016\1668897 VTrans Newport Supplemental Design\700 Reports\Final Report\Tables\Tbl 3 DCP testing summary.xlsx
November 2017 3 Project No.1668897
Table 3:
Exploration ID Location(1) BlowsPenetration
(mm)
DCP Penetration
Index (mm/blow)
Cumulative
Penetration (ft)
Calculated SPT
N Value(2)
Average Calculated
SPT N Value(3) Assumed Phi Notes
35 -
Dynamic Cone Penetrometer Test Results Geotechnical Design Recommendation Report VT Route 191 Embankment Slide Newport, Vermont
DCP-1
Below
Proposed
Access Road
123 77 26 0.25 193 42 14 0.39 253 91 30 0.69 171 60 60 0.89 121 75 75 1.13 111 55 55 1.31 132 101 51 1.64 132 81 41 1.91 152 91 46 2.21 145 23 5 2.28 44
10 57 6 2.47 3910 58 6 2.66 392 36 18 0.12 222 28 14 0.21 252 57 29 0.40 185 39 8 0.52 343 84 28 0.80 182 31 16 0.90 243 68 23 1.13 202 51 26 1.29 193 46 15 1.44 243 23 8 1.52 343 28 9 1.61 313 24 8 1.69 335 51 10 1.86 304 52 13 2.03 263 45 15 2.18 243 54 18 2.35 223 62 21 2.56 213 71 24 2.79 203 61 20 2.99 211 101 101 0.33 105 46 9 0.48 311 91 91 0.30 101 86 86 0.58 101 79 79 0.84 111 52 52 1.01 131 26 26 1.10 195 81 16 1.36 245 17 3 1.42 515 15 3 1.47 545 38 8 1.59 345 126 25 2.00 191 63 63 2.21 121 77 77 2.46 115 151 30 2.96 171 309 309 1.01 61 126 126 1.43 91 54 54 1.60 132 86 43 1.89 152 88 44 2.18 143 130 43 2.60 143 104 35 2.94 161 114 114 0.37 9 91 270 270 1.26 63 131 44 1.69 143 92 31 1.99 173 72 24 2.23 192 93 47 2.53 143 90 30 2.83 171 164 164 0.54 83 115 38 0.92 152 61 31 1.12 173 85 28 1.39 182 87 44 1.68 143 69 23 1.91 203 86 29 2.19 183 84 28 2.46 182 105 53 2.81 13
18
13
34
24
27
22
35
32
35
35
35
32
32
32
32
- Snow on ground
DCP-14Upper Slide
Slope
Between
Proposed
Access Road
& Route
191,
4.5' from
B-402
DCP-13
DCP-17Upper Slide
Slope
DCP-16Upper Slide
Slope
DCP-12
Between
Proposed
Access Road
& Route
191
Upper Slide
SlopeDCP-15
DCP-14aUpper Slide
Slope
- Snow on ground
- Offset by rock / roots/ something hard;
moved rod over a bit and tried again.
- Snow on ground
- Harder section between 1.46'
(44.4 cm) and 1.51' (46.1 cm)
penetration; possibly wood.
-
-
-
20
10
32
11
15
10
15
12
17
17
16
P:\Projects\2016\1668897 VTrans Newport Supplemental Design\700 Reports\Final Report\Tables\Tbl 3 DCP testing summary.xlsx
November 2017 4 Project No.1668897
Table 3:
Exploration ID Location(1) BlowsPenetration
(mm)
DCP Penetration
Index (mm/blow)
Cumulative
Penetration (ft)
Calculated SPT
N Value(2)
Average Calculated
SPT N Value(3) Assumed Phi Notes
35 -
Dynamic Cone Penetrometer Test Results Geotechnical Design Recommendation Report VT Route 191 Embankment Slide Newport, Vermont
DCP-1
Below
Proposed
Access Road
122 43 22 0.14 202 194 97 0.78 101 81 81 1.04 111 59 59 1.24 121 43 43 1.38 151 120 120 1.77 91 69 69 2.00 121 56 56 2.18 131 70 70 2.41 111 53 53 2.59 131 63 63 2.79 122 55 28 2.97 181 114 114 0.37 9 91 283 283 1.30 61 83 83 1.57 111 48 48 1.73 141 88 88 2.02 101 49 49 2.18 141 59 59 2.38 121 52 52 2.55 133 103 34 2.88 165 51 10 0.17 305 39 8 0.30 345 49 10 0.46 305 34 7 0.57 36
Notes:
Made By: LLMChecked By: CJSReviewed By: CCB
4) Per ASTM D6951/D6951M - 09 (Reapproved 2015) DCP tests are not valid once the top of the rod has deflected 3" from plumb.
1) Approximate location of DCP locations and are shown on Figure 3 "2017 Boring Location Map and Final Design Elements."
3) The average calculated SPT N value is an average of the calculated SPT N values over approximately 1 ft of penetration.
DCP-20Upper Slide
Slope
Upper Slide
SlopeDCP-19
DCP-18Upper Slide
Slope
12
13
10
13
32
2) DCP Penetration Index correlated to SPT N-value using Figure 11 in the MinnesotaDOT User Guide to the Dynamic Cone Penetrometer
(1996). This value was then converted from the SPT mm/blow value to an SPT N-value by dividing 305mm(1ft) by the SPT mm/blow value.
15
35
32
32 -
- Deflection issue.
-
P:\Projects\2016\1668897 VTrans Newport Supplemental Design\700 Reports\Final Report\Tables\Tbl 3 DCP testing summary.xlsx
November 2017 Page 1 of 1 Project No: 1668897
Gravel (%)
Sand (%)
Silt(%)
1D 1.0 - 3.0 853.0 - 851.0 - 16.5 12.8 - - NP - 53.3 30.2 16.5 A-1-b SM Broken rock within sample.2D 5.0 - 7.0 849.0 - 847.0 - 58.3 13.5 - - NP - 10.9 30.8 58.3 A-4 ML -3D 10.0 - 12.0 844.0 842.0 - 49.0 11.5 - - NP - 13.1 38.0 49.0 A-4 SM -4D 15.0 - 17.0 839.0 - 837.0 45.9 11.8 - - NP - 23.3 30.8 45.9 A-4 SM -5D 20.0 - 22.0 834.0 832.0 64.8 14.4 - - NP - 10.0 25.2 64.8 A-4 ML Some clay within sample.6D 25.0 - 27.0 829.0 827.0 53.6 14.0 - - NP - 11.0 35.4 53.6 A-4 ML -
8D 30.0 - 32.0 824.0 822.0 - 46.8 33.9 - - NP - 10.3 43.0 46.8 A-4 SM A small amount of organic material within sample.
9D 40.0 - 42.0 814.0 812.0 - 82.8 23.6 41 24 17 0.0 5.7 11.5 82.8 A-7-6 CL -10D 45.0 - 46.3 809.0 807.7 - 70.9 16.1 - - NP - 10.9 18.2 70.9 A-4 ML -11D 50.0 - 52.0 804.0 - 802.0 - 88.2 22.9 - - NP - 5.9 5.9 88.2 A-4 ML -
1D 0.0 - 2.0 820.0 - 818.0 - 19.6 19.9 - - NP - 38.7 41.7 19.6 A-1-b SM Asphalt pavement and plant material within sample.
5D 17.0 - 19.0 803.0 801.0 - 49.0 13.9 - - NP - 16.8 34.2 49.0 A-4 SM -7D 25.0 - 27.0 795.0 793.0 - 96.6 26.9 35 24 11 0.3 1.6 1.8 96.6 A-6 ML -
8D 30.0 - 32.0 790.0 - 788.0 - 71.8 16.3 - - NP - 9.8 18.4 71.8 A-4 ML Some cohesion observed in field sample
1D 0.0 - 2.0 862.0 - 860.0 - 24.1 13.1 - - NP - 46.9 28.9 24.1 A-1-b GM Broken rock, grass, grass roots, and plant material within sample.
2D 5.0 - 7.0 857.0 - 855.0 - 33.6 9.3 - - NP - 31.5 34.9 33.6 A-2-4 SM Broken rock within sample.3D 10.0 - 12.0 852.0 - 850.0 - 9.9 5.1 - - NP - 73.9 16.2 9.9 A-1-a GP-GM Broken rock within sample.4D 15.0 - 17.0 847.0 - 845.0 - 13.6 8.2 - - NP - 64.1 22.3 13.6 A-1-a GM Broken rock within sample.6D 25.0 - 27.0 837.0 - 835.0 - 90.8 21.2 32 20 12 0.1 5.2 3.9 90.8 A-6 CL -7D 30.0 - 32.0 832.0 - 830.0 - 91.8 23.2 37 22 15 0.1 2.6 5.6 91.8 A-6 CL -
Notes:
Prepared By: LLM
Checked By: CJS
Reviewed By: CCB
Liquidity Index
AASHTOAASHTO Soil
Classification4,5USCS Soil
Classification4,5 Comments
Table 4: Summary of Laboratory Soil Testing Results Geotechnical Design Report Route 191 Landslide Newport, Vermont
Test Boring Designation1
Existing Ground Surface Elevation 2
(ft)
Sample Number
Sample Depth Below Ground
Surface (ft)
Approximate Sample Elevation
(ft)
Sieve Minus No. 200 (%):
Natural Moisture
Content (%)
Liquid Limit (%)
Plastic Limit (%)
Plasticity Index (%)
B-401 854
Direct Shear Friction
Angle (°)3
27.1
5. Laboratory testing and material classification for split spoon samples was performed by VTrans. Complete laboratory test results for soil testing are provided in Appendix B-1. 4. AASHTO and USCS symbols assigned based on interpretation of laboratory test results.
1. Test boring locations are shown in Figure 3 "2017 Boring Location Map and Final Design Elements."
820B-402
B-403 862
2. Boring locations were not surveyed. As-drilled elevations are derived from electronic site plan in Note 1.
3. Direct shear sample was reconstituted from three samples in boring B-401 (4D,5D,6D).
P:\Projects\2016\1668897 VTrans Newport Supplemental Design\700 Reports\Final Report\Tables\Tbl 4 Soil Index Tests.xlsx
FIGURES
SITE LOCATION
REFERENCES
SITE LOCATION MAP
GEOTECHNICAL DESIGN REPORTROUTE 191 EMBANKMENT, NEWPORT, VERMONT 1
710
710
720
730
740
740
740
750
760
770
780
790
800
810
820
830
840850
850
850
860
730
740
740
740
750
760
770
780
810
820
740
750
760
770
780
790
800
810
810810
820
830
840
850
860
ABANDONED POWER CANAL
CLYDE RIVER
GREAT BAY HYDRO ROAD
UNDERDRAINSYSTEM
A' 4
A4
110+00111+00112+00113+00114+00115+00116+00117+00118+00119+00
120+00VERMONTROUTE 191
B-205 / MW-3 30-INCH DIA.CMP CULVERT
WIRELESSMULTIPLEXER
APPROXIMATEHEAD SCARP OF
DEEP-SEATEDSLIDE
B-209
MW1
I-1
I-2
B-1
B-2
B-3
B-5
B-6
B-7
B-8
B-201
B-202
B-203
B-213
B-214
B-215
B-216
B-302a
B-304a
PTWa
B-316aB-316b
B-311a
B-311b
B-313a
B-313bB-212
CULVERT HEADWALL(FAILED AS OF 2017)
(NOT FUNCTIONAL)
CLAY EXPOSED IN STREAM BANKS(LOCATION APPROXIMATE
CLAY OUTCROP WITH SMALLSCALE SLOPE FAILURES(LOCATION APPROXIMATE)
B-318b
SECONDARY SURFICIALSCARP FEATURES (SHALLOWSLOUGHS OR SLIDES) NOTED
IN THIS AREA
B-4
B-204
MW2B-305b
B-304b
B-304c
PTWbPTWc
B-306a
B-306b
B-307aDATA LOGGER
APPROXIMATEHEAD SCARP OF
DEEP-SEATEDSLIDE
B-307cB-307b
EXISTING CONDITIONS (2012) AND LOCATIONSOF BORINGS AND INSTRUMENTATION
INSTALLED FROM 1966 TO 2013
2
GEOTECHNICAL DESIGN REPORTROUTE 191 EMBANKMENT STABILIZATION
NEWPORT, VERMONTTITLE
PROJECT
SCALEDESIGN
PROJECT No. FILE No.
CADD
CHECKREVIEW
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166-8897
FIGURE
1668897A002.dwg
1:50JRS 2017/07/14
RWC 2017/07/14
JRS 2017/07/14MSP 2017/07/14
GOLDER BORINGS AND REMOTE MONITORING EQUIPMENT INSTALLED JUNE / JULY 2013
NOTES
LEGEND
VTRANS BORINGS INSTALLED 1966 TO 1989
0
FEET
50 100 150
SCALE
LOCAL STATION (FEET)114+00
10 - FOOT CONTOUR AND ELEVATION (FEET MEAN SEA LEVEL) 740
A4
CROSS SECTION LOCATION, DIRECTION AND FIGURE WHEREPRESENTED
APPROXIMATE LOCATION OF HEAD SCARP OF DEEP SEATEDSLIDE (NOT SURVEYED) OBSERVED BY GOLDER MARCH 2012
UNDERDRAIN SYSTEM INSTALLED 1971 AND FLOW DIRECTION(LOCATION APPROXIMATE)
CMP CULVERT
1. BASEMAP PROVIDED BY VTRANS DRAWING FILE TITLED, "NEWPORT VT 191 REVISEDBORE PLAN 020409.DGN". DATED MARCH 20, 2012.
2. INSTALLED LOCATIONS AND ELEVATIONS SURVEYED BY CLD CONSULTINGENGINEERS, INC. 07/24/13. COORDINATES REFERENCE THE NAD83(96) VERMONTSTATE PLANE. ELEVATIONS REFERENCE THE NORTH AMERICAN VERTICAL DATUMOF 1988 (NAVD88).
3. INCLINOMETERS I-1 AND I-2 NO LONGER FUNCTIONAL
4. INCLINOMETER DISPLACEMENT NOT WELL DEFINED AT B-212 AND B-215,THEREFORE NO ARROW IS SHOWN.
5. HORIZONTAL DRAIN LOCATIONS FROM VTRANS MAP TITLED "LOCATION OFHORIZONTAL DRAINS, INSTALLED MAY-JUNE 1973", FIGURE 2, SCALE 1"=100'.
WIRELESS MULTIPLEXER
DATA LOGGER
PUMPING TEST WELL
BORING AND CLUSTER OF 3 OPEN STANDPIPE PIEZOMETERS
BORING, MANUALLY READ INCLINOMETER AND AUTOMATEDGROUTED IN-PLACE VIBRATING WIRE (VW) PRESSURETRANSDUCERS (2 TO 3 PER BORING)
BORING, AUTOMATED SHAPE ACCELARRAY INCLINOMETER ANDGROUTED IN-PLACE VW PRESSURE TRANSDUCERS (2 TO 3 PERBORING)
BORING, AUTOMATED IN-PLACE VW INCLINOMETER ANDGROUTED IN-PLACE VW PRESSURE TRANSDUCERS (2 TO 3 PERBORING)
MONITORING WELL WITH VW PIEZOMETER
PTWa
B-304a
B-302a
B-305b
B-306a
B-316a
BORINGS DRILLED 2006 - 2009
BORINGS AND INCLINOMETERS INSTALLED 2006 - 2009, ARROWINDICATES APPROXIMATE HORIZONTAL DISPLACEMENT DIRECTION
MONITORING WELLS INSTALLED 2008
INCLINOMETER INSTALLED 1989
AUGER BORINGS 1971 - 1974
CASED BORINGS 1966 - 1974
2 - FOOT CONTOUR AND ELEVATION (FEET MEAN SEA LEVEL)
B-209
B-201
MW-1
I-1
B-5
APPROXIMATE EXTENT OF COUNTER BERM INSTALLED 1991
APPROXIMATE EXTENT OF CLAY OUTCROP MAPPED IN 2012
HORIZONTAL DRAINS AS INSTALLED 1973
1991 UNDERDRAIN
1991 UNDERDRAIN
ABANDONED POWER CANAL
CLYDE RIVER
710
710
720
730
740
740
740
750
760
770
780
790
800
810
820
830
840850
850
850
860
870
880
890
900
730
740
740
740
750
760
770
780
810
820
GREAT BAY HYDRO ROAD
UNDERDRAIN SYSTEM
740
750
760
770
780
790
800
810
810810
820
830
840
850
860
107+00108+00109+00110+00111+00112+00113+00114+00115+00116+00117+00118+00119+00
120+00
VERMONTROUTE 191
EXISTING30-INCHDIA. CMPCULVERT
APPROXIMATEHEAD SCARP OF
DEEP-SEATEDSLIDE
B-209
DCP-1DCP-12
DCP-11
DCP-10
DCP-20
DCP-19DCP-18
DCP-17
DCP-15
B-401
CULVERTHEADWALL(FAILED ASOF 2017)
DCP-16
DCP-14
PROPOSEDTOE DRAINOUTLET
PROPOSEDTOE DRAIN
PROPOSEDTOE DRAININLET
PROPOSED SLOPESTABILIZATION LIMITPROPOSED SLOPE
STABILIZATION LIMIT
ACCESS ROAD(EXISTING)
AW-3
PROPOSEDDISCHARGEHEADER PIPE
PROPOSED PRECASTCONCRETE BUILDING
AW-1
PROPOSED ELECTRIC /CONTROL CONDUIT (TYP)
PROPOSEDFLOW METERVAULT (TYP)
C C C C C C CC
U
PWTa(EXISTING)
AW-2
APPROXIMATEHEAD SCARP OF
DEEP-SEATEDSLIDE
PROPOSEDDISCHARGEHEADERPIPE
PROPOSEDGROUNDWATEROUTFALL
PROPOSEDHEADSCARPSEAL AREA
B-403
DCP-2
DCP-3DCP-4
DCP-5
DCP-9DCP-8
DCP-7
DCP-6
DCP-13 B-402
50+00
51+00DCP-1
52+00
53+00
54+0055+00
56+00
PROPOSED42-INCHCULVERT
PROPOSEDCUT OFFTRENCHDRAIN
49+0
0
EXISTING18 INCHCULVERT
PROPOSEDACCESSROAD
2017 BORING LOCATION MAP ANDPROPOSED FINAL DESIGN ELEMENTS
3
GEOTECHNICAL DESIGN REPORTROUTE 191 EMBANKMENT STABILIZATION
NEWPORT, VERMONTTITLE
PROJECT
SCALEDESIGN
PROJECT No. FILE No.
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166-8897
FIGURE
1668897A003
1:50CJS 2017/07/14
RWC 2017/07/14
JRS 2017/07/14MSP 2017/07/14
NOTES
LEGEND
0
FEET
50 100 150
SCALE
LOCAL STATION (FEET)114+00
10 - FOOT CONTOUR AND ELEVATION (FEET MEAN SEA LEVEL) 740
APPROXIMATE LOCATION OF HEAD SCARP OF SLIDE (NOTSURVEYED) OBSERVED BY GOLDER MARCH 2012
UNDERDRAIN SYSTEM INSTALLED 1971 AND FLOW DIRECTION(LOCATION APPROXIMATE)
CMP CULVERT
1. BASEMAP PROVIDED BY VTRANS DRAWING FILE TITLED, "NEWPORT VT 191 REVISEDBORE PLAN 020409.DGN". DATED MARCH 20, 2012.
2. LOCATIONS OF DCP AND 400 SERIES BORINGS ARE BASED ON FIELDMEASUREMENT. ACTUAL LOCATIONS MAY VARY FROM THOSE SHOWN.
3. PROPOSED STABILIZATION FEATURES BASED, IN PART, ON PRELIMINARY PLANSPROPOSED BY STANTEC AND GOLDER TITLED "PROPOSED IMPROVEMENT,NEWPORT CITY, COUNTY OF ORLEANS, VT ROUTE 191 (PRINCIPAL ARTERIAL)",FEBRUARY 10, 2017.
2 - FOOT CONTOUR AND ELEVATION (FEET MEAN SEA LEVEL)
DCP-1
B-401
GOLDER EXPLORATIONS 2017
GOLDER APRIL 2017 DYNAMIC CONE PENTROMETER PROBELOCATION
GOLDER MARCH 2017 BORINGS
PROPOSED HEADSCARP SEALING CONSTRUCTION (SEE FIGURE 7 FOR DESIGN DETAIL)
PROPOSED HEADSCARP SEAL AREA
RELOCATE AND REPLACE UNDERDRAIN SECTION
DISCHARGE HEADER PIPE
ELECTRIC / CONTROL CONDUIT, UNDERGROUNDC
PROPOSED GROUNDWATER EXTRACTION WELL
EXISTING GROUNDWATER EXTRACTION WELL
15'15'
1'(TYP.)
N
17
600
650
700
750
800
850
0 100 200 300 400 500 600 700
600
650
700
750
800
850
ELEV
ATIO
N (F
T-M
SL)
ELEV
ATIO
N (F
T-M
SL)
HORIZONTAL SCALE (FT)
-100
EOB
B-302AO/L
B-20120 FT (W)
B-4
B-305 A,B12 FT (E)
EOB
EOB
EOB
B-306A,B2 FT (W)
EOB
EOB
B-21369 FT (E)
EOB
B-316 A,BO/L
EOB
B-311A,B63 FT (W)GSE @ BORING = 721 FT
EOB
B-215 B-313A,B43 FT (W)
EOB
N
2435953738655116254325758357
80RR12395R
117*
49
34 R*93*81*
R*R*R*R*R152
R*R*R
7
N124012302229151834169312883123R*R*R*R*
R* R*R*76*52*
80*R*R*R*R*
N
4
105
95
789
4722
73R9384
66
117605249
40
N762222622 3335
2728
29
274042
53 46
7585
41
152
1918
59
1816
53
20
2127
26
24
42
50
28
R
-140
ABANDONED POWER CANAL
CLYDE RIVER
EXISTING GROUND SURFACE
EXISTING GROUND SURFACE
A'NORTH
ASOUTH
EMBANKMENT FILL
UPPER SILTS AND CLAYS
LOWER CLAY
LOWER SANDS AND GRAVELS
750
LOWER SILTS / WEATHERED BEDROCK
?
LOWER SILTS / WEATHERED BEDROCK
MIDDLE SILTS AND SANDS
MIDDLE SANDS AND GRAVELS
BEDROCK
UPPER SILTS AND SANDS
LOWER CLAY
UPPER SILTS AND CLAYS
?
MIDDLE SANDS AND GRAVELS
MIDDLE SILTS AND SANDS
?
BEDROCK
ROAD FILL
VERMONT ROUTE 191℄
PTW A,B,CAPPROXIMATE CL
EOB
CROSS SECTION A - A'GEOTECHNICAL DATA
4
GEOTECHNICAL DESIGN REPORTROUTE 191 EMBANKMENT
NEWPORT, VERMONTTITLE
PROJECT
SCALEDESIGN
PROJECT No. FILE No.
CADD
CHECKREVIEW
REVISION DESCRIPTION CADD CHK RVWDESDATEREV
J:\D
raw
ings
\201
6\16
6889
7 VT
RAN
S N
ewpo
rt, V
T\PR
OD
UC
TIO
N\1
6688
97A0
04.d
wg
| Lay
out:
4 C
RO
SS S
ECTI
ON
A-A
' GEO
TEC
HN
ICAL
DAT
A | M
odifi
ed: r
clar
k 07
/14/
2017
9:1
0 AM
| Pl
otte
d: rc
lark
07/
14/2
017
166-8897
FIGURE
1668897A004.dwg
AS SHOWNNSC 2014-06-16
RWC 2017/07/14
JRS 2017/07/14MSP 2017/07/14
0
FEET
30 60 90
SCALE
SOIL CLASSIFICATIONS
NOTES
LEGEND
1. SEE BORING LOCATION PLAN FOR BORING LOCATIONS.
2. SEE BORING LOGS FOR SOIL LITHOLOGIC DESCRIPTIONS.
3. SEE LABORATORY TEST REPORTS FOR COMPLETE LABORATORY DATA.
4. GROUNDWATER ELEVATION ESTIMATES BASED ON MEASUREMENTS TAKEN AT THETIME OF SUBSURFACE EXPLORATIONS.
5. BEDROCK CONTOURS INTERPRETED FROM BOREHOLE DATA (GOLDER 2014). ACTUALENCOUNTERED BEDROCK SURFACE ELEVATIONS WILL VARY AND BE MORE ERRATICTHAN SHOWN.
6. THIS GENERALIZED SUBSURFACE PROFILE IS INTENDED TO CONVEY TRENDS INSUBSURFACE CONDITIONS. THE BOUNDARIES BETWEEN STRATA ARE APPROXIMATEAND IDEALIZED, AND HAVE BEEN DEVELOPED BY INTERPRETATIONS OF WIDELYSPACED EXPLORATIONS AND EXAMPLES. ACTUAL SOIL AND ROCK TRANSITIONS MAYVARY AND ARE PROBABLY MORE ERRATIC. FOR MORE SPECIFIC INFORMATION REFERTO EXPLORATION LOGS.
7. HORIZONTAL DATUM IS VERMONT STATE PLANE NAD83 (96). VERTICAL DATUM ISNAVD88.
BR638
24
B-307
EOB
= BORING LOCATION - 300 SERIES = GOLDER OTHER = VTRANS
= END OF BORING
= OBSERVED GROUNDWATER ELEVATION (FT)
= BEDROCK ELEVATION (FT-MSL)
= N - VALUE
EL.758.4 = GROUND SURFACE ELEVATION
* = SAMPLED WITH A 3" SPLIT SPOON
EMBANKMENT FILL: A-1-B/A-2-4/A-4, GRAY BROWN TO DARK GRAY BROWN, MOIST TO WET, LOOSE TO DENSE, FINETO COARSE SAND, TRACE TO SOME SILT, TRACE TO LITTLE GRAVEL, LAYERS OF GRAY SILT THROUGHOUT.
UPPER SILTS AND SANDS: A-2-4/A-4, GRAY BROWN TO DARK BROWN, MOIST, MEDIUM DENSE TO DENSE, LAYERS OFFINE TO MEDIUM SAND, FINE SAND, AND SILT, TRACE COARSE SAND AND FINE GRAVEL THROUGHOUT.
UPPER SILTS AND CLAYS: A-4/A-6, DARK GRAY, MOIST TO WET, STIFF TO VERY STIFF, LAYERS OF SILTY CLAY,CLAYEY SILT, AND SILTY FINE SAND.
MIDDLE SILTS AND SANDS: A-4, GRAY, DRY TO MOIST, VERY DENSE, LAYERS OF SILT, SILTY FINE TO MEDIUM SAND,AND CLAYEY SILT, TRACE TO LITTLE ROUNDED GRAVEL THROUGHOUT. OCCASIONAL LAYERS OF DARK GRAY FINETO MEDIUM SAND ENCOUNTERED.
MIDDLE SANDS AND GRAVELS: A-1-B/A-2-4, MEDIUM BROWN AND ORANGE BROWN, MOIST, VERY DENSE, SILT, SOMEFINE SAND, SOME GRAVEL. POCKETS OF GRAY, MOIST, VERY DENSE, FINE TO MEDIUM SAND ENCOUNTERED.
LOWER CLAYS: A-7-5/A-7-6, LAYERED ORANGE BROWN AND GRAY CHANGING TO BROWN AND GRAY TOWARDS THERIVER, DRY TO MOIST, HARD, VARVED SILTY CLAY AND SILTY FINE SAND. ZONES OF DISTURBANCE ANDSLICKENSIDES ENCOUNTERED THROUGHOUT DEPOSIT. SEAMS CONTAINING SAND AND GRAVEL ENCOUNTEREDWITHIN DEPOSIT SOUTH OF B-306. VARVE THICKNESS RANGES FROM 0.1 INCHES UP TO 2 INCHES. DEPOSITS OFNON-VARVED CLAY UP TO 5 FEET THICK ENCOUNTERED.
LOWER SANDS AND GRAVELS: A-1-B, BROWN AND GRAY, MOIST, MEDIUM DENSE TO VERY DENSE, FINE TO COARSESAND, SOME TO LITTLE GRAVEL, LITTLE SILT.
LOWER SILTS / WEATHERED BEDROCK: A-4, DARK BROWN, MOIST TO WET, DENSE, SILTS AND SILTY FINE SANDS.FRACTURED BEDROCK ENCOUNTERED ALONG BOTTOM OF DEPOSIT PRIOR TO REACHING BEDROCK.
REFERENCES1.) BASEMAP PROVIDED BY VTRANS DRAWING FILE TITLED, "NEWPORT VT 191
REVISED BORE PLAN 020409.DGN". DATED MARCH 20, 2012.2.) TOE DRAIN ELEVATIONS BASED ON THE STANTEC DRAWING "TOE DRAIN PROFILE
PRO-8" DATED 02/10/2017.3.) HORIZONTAL DRAIN ALIGNMENT CONSTRUCTED USING STANTEC DRAWING
"ALIGNMENT PLAN AP-2" DATED 02/10/2017.
POTENTIAL TRENCHINGIMPACT ON HORIZONTAL DRAINS
GEOTECHNICAL DESIGN REPORTROUTE 191 EMBANKMENT STABILIZATION
NEWPORT, VERMONT
FIGURE 7
1.) LOCATIONS OF HORIZONTAL DRAINS ARE APPROXIMATE AND ARE BASED OFF OFHISTORICAL CONSTRUCTION RECORDS AND DRAWINGS PRIOR TO COUNTERBERMCONSTRUCITON. ACTUAL FIELD CONDTIONS MAY VARY.
2.) TOE DRAIN TRENCH LAYOUT SCALED BY HAND FROM STANTEC DRAWING INREFERENCE 3 AND SHOWN IN FIGURE 3.
3.) THE SCALE OF THE HORIZONTAL DRAINS IN THIS FIGURE ARE EXAGGERATED FORCLARITY.
NOTES
TOE DRAIN TRENCH PROFILESCALE: 1" = 20'
EDGE OF PAVEMENT
ROAD SUBBASE
ITEM 649.11 GEOTEXTILESEPERATION
9" (MIN.) UPPER SANDCUSHION LAYER
MODIFIED 703.03 (1" MINUS)
30 mil (TYP) GEOMEMBRANE LINER
6" (MIN.) LOWER SAND CUSHION LAYERMODIFIED 703.03 (1" MINUS)
GRADE AND PROOFROLL NATIVESUBGRADE SOIL AT A MINIMUM 2%
SLOPE TO PROMOTE DRAINAGE
REMOVE AND REPLACE EXISTING TOPSOIL &EMBANKMENT MATERIAL (EARTH BORROW 703.02)
(DEPTH VARIES TO MATCH EXISTING GRADE)(9" MIN THICKNESS REQUIRED)
NOTES:1) DRAWING IS NOT TO SCALE AND IS EXAGGERATED TO SHOW DETAIL.2) GEOMEMBRANE LINER SHALL EXTEND INTO DRAINAGE MATERIAL
SURROUNDING THE EXISTING UNDERDRAIN.3) GEOMEMBRANE LINER SHALL EXTEND UNDER ROADWAY A MINIMUM OF
1FT (12") BEYOND THE EDGE OF PAVEMENT.4) REFER TO FIGURE 3 FOR HEADSCARP SEAL LOCATION.5) REFER TO GEOMEMBRANE LINER SPECIAL PROVISION FOR
INSTALLATION REQUIREMENTS.
xxxx
xxxx
xxxx
xxxx
xxxx
xxxxxx
xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
xxxx
xxxx
xxx
18"
18"
12"(MIN.)EXISTING UNDERDRAIN
(REMOVE & REPLACE IN KIND)
704.16 DRAINAGE AGGREGATE(3/4" STONE)
01
in
166-8897SUBTITLEA
FIGURE
80
2017/07/14
CJS
RWC
MCM
CCB
GEOTECHNICAL DESIGN REPORTROUTE 191 EMBANKMENT STABILIZATIONNEWPORT, VERMONT
VERMONT AGENCY OF TRANSPORTATION2178 AIRPORT ROAD, UNIT BBERLIN, VT 05641-8628
TYPICAL HEADSCARP SEAL SECTION &GEOMEMBRANE TIE-IN UNDERDRAIN DETAIL
TITLE
PROJECT NO. REV.
PROJECTCLIENT
IF T
HIS
MEA
SUR
EMEN
T D
OES
NO
T M
ATC
H W
HAT
IS S
HO
WN
, TH
E SH
EET
SIZE
HAS
BEE
N M
OD
IFIE
D F
RO
M: A
NSI
A
CONSULTANT
PREPARED
DESIGNED
REVIEWED
APPROVED
YYYY-MM-DD
Path: \\manchester\cadd\Drawings\2016\1668897 VTRANS Newport, VT\PRODUCTION\ | File Name: 1668897A005.dwg
APPENDIX A 400 SERIES BORING LOGS
Table A-1
TERMS DESCRIBING
UNIFIED SOIL CLASSIFICATION SYSTEM DENSITY/CONSISTENCY
MAJOR DIVISIONSGROUP
SYMBOLS TYPICAL NAMES
Coarse-grained soils (more than half of material is larger than No. 200
COARSE- CLEAN GW Well-graded gravels, gravel- sieve): Includes (1) clean gravels; (2) silty or clayey gravels; and (3) silty,
GRAINED GRAVELS GRAVELS sand mixtures, little or no fines. clayey or gravelly sands. Consistency is rated according to standard
SOILS penetration resistance.
(little or no GP Poorly-graded gravels, gravel Modified Burmister System
fines) sand mixtures, little or no fines. Descriptive Term Portion of Total
trace 0% - 10%
little 11% - 20%
GRAVEL GM Silty gravels, gravel-sand-silt some 21% - 35%
WITH mixtures. adjective (e.g. sandy, clayey) 36% - 50%
FINES
(Appreciable GC Clayey gravels, gravel-sand-clay Density of Standard Penetration Resistance
amount of mixtures. Cohesionless Soils N-Value (blows per foot)
fines) Very loose 0 - 4
Loose 5 - 10
CLEAN SW Well-graded sands, gravelly Medium Dense 11 - 30
SANDS SANDS sands, little or no fines Dense 31 - 50
Very Dense > 50
(little or no SP Poorly-graded sands, gravelly
fines) sand, little or no fines.
Fine-grained soils (more than half of material is smaller than No. 200
sieve): Includes (1) inorganic and organic silts and clays; (2) gravelly, sandy
SANDS SM Silty sands, sand-silt mixtures or silty clays; and (3) clayey silts. Consistency is rated according to shear
WITH strength as indicated.
FINES Approximate
(Appreciable SC Clayey sands, sand-clay Undrained
amount of mixtures. Consistency of SPT N-Value Shear Field
fines) Cohesive soils blows per foot Strength (psf) Guidelines
WOH, WOR,
ML Inorganic silts and very fine WOP, <2
sands, rock flour, silty or clayey Soft 2 - 4 250 - 500 Thumb easily penetrates
fine sands, or clayey silts with Medium Stiff 5 - 8 500 - 1000 Thumb penetrates with
SILTS AND CLAYS slight plasticity. moderate effort
Stiff 9 - 15 1000 - 2000 Indented by thumb with
FINE- CL Inorganic clays of low to medium great effort
GRAINED plasticity, gravelly clays, sandy Very Stiff 16 - 30 2000 - 4000 Indented by thumbnail
SOILS clays, silty clays, lean clays. Hard >30 over 4000 Indented by thumbnail
(liquid limit less than 50) with difficulty
OL Organic silts and organic silty Rock Quality Designation (RQD):
clays of low plasticity. RQD = sum of the lengths of intact pieces of core* > 100 mm
length of core advance *Minimum NQ rock core (1.88 in. OD of core)
MH Inorganic silts, micaceous or
diatomaceous fine sandy or Correlation of RQD to Rock Mass Quality
SILTS AND CLAYS silty soils, elastic silts. Rock Mass Quality RQD
Very Poor <25%
CH Inorganic clays of high Poor 26% - 50%
plasticity, fat clays. Fair 51% - 75%
Good 76% - 90%
(liquid limit greater than 50) OH Organic clays of medium to Excellent 91% - 100%
high plasticity, organic silts. Desired Rock Observations: (in this order)
Color (Geological Society of America Rock Color Chart)
Texture (aphanitic, fine-grained, etc.)
HIGHLY ORGANIC Pt Peat and other highly organic Strength (ISRM Classification per Table A-2)SOILS soils. Lithology (igneous, sedimentary, metamorphic, etc.)
Hardness (very hard, hard, mod. hard, etc.)
Desired Soil Observations: (in this order) Weathering (fresh, very slight, slight, moderate, mod. severe,
Color (Munsell color chart) severe, etc.)
Moisture (dry, damp, moist, wet, saturated) Geologic discontinuities/jointing:
Density/Consistency (from above right hand side) -dip (horiz - 0-5, low angle - 5-35, mod. dipping -
Name (sand, silty sand, clay, etc., including portions - trace, little, etc.) 35-55, steep - 55-85, vertical - 85-90)
Gradation (well-graded, poorly-graded, uniform, etc.) -spacing (very close - <5 cm, close - 5-30 cm, mod.
Plasticity (non-plastic, slightly plastic, moderately plastic, highly plastic) close 30-100 cm, wide - 1-3 m, very wide >3 m)
Structure (layering, fractures, cracks, etc.) -tightness (tight, open or healed)
Bonding (well, moderately, loosely, etc., if applicable) -infilling (grain size, color, etc.)
Cementation (weak, moderate, or strong, if applicable, ASTM D 2488) Formation (Waterville, Ellsworth, Cape Elizabeth, etc.)
Geologic Origin (till, marine clay, alluvium, etc.) RQD and correlation to rock mass quality (very poor, poor, etc.)
Unified Soil Classification Designation ref: AASHTO Standard Specification for Highway Bridges
Groundwater level 17th Ed. Table 4.4.8.1.2A
Recovery
Sample Container Labeling Requirements:
Project Name / Town Blow Counts Boring Number Sample Recovery Sample Number Date Sample Depth Personnel Initials
0 - 250 Fist easily PenetratesVery Soft
(mo
re t
ha
n h
alf o
f m
ate
ria
l is
sm
alle
r th
an N
o. 2
00
sie
ve
siz
e)
(mo
re t
ha
n h
alf o
f m
ate
ria
l is
la
rge
r th
an N
o. 2
00
sie
ve
siz
e)
(mo
re t
ha
n h
alf o
f co
ars
e
fra
ctio
n is la
rge
r th
an N
o.
4
sie
ve
siz
e)
(mo
re t
ha
n h
alf o
f co
ars
e
fra
ctio
n is s
ma
ller
tha
n N
o. 4
sie
ve
siz
e)
Key to Soil and Rock Descriptions Including Boring Log Terms and Field Identification Information
September 2012
Table A-2
Classification of Rock Material Strengths1
Grade Description Field Identification
Approx. Range of Uniaxial Compressive Strength
MPa psi
S1 Very soft clay Easily penetrated several inches by fist
<0.025 <4
S2 Soft clay Easily penetrated several inches by thumb
0.025-0.05 4-7
S3 Firm clay Can be penetrated several inches by thumb with moderate effort
0.05-0.10 7-15
S4 Stiff clay Readily indented by thumb but penetrated only with great effort
0.10-0.25 15-35
S5 Very stiff clay Readily indented by thumbnail 0.25-0.50 35-70
S6 Hard clay Indented with difficulty by thumbnail >0.50 >70
R0 Extremely weak rock Indented by thumbnail 0.25-1.0 35-150
R1 Very weak rock Crumbles under firm blows with point of geological hammer; can be peeled by a pocket knife
1-5 150-725
R2 Weak rock
Can be peeled by a pocket knife with difficulty; shallow indentations made by firm blow with point of geological hammer
5-25 725-3,500
R3 Medium strong rock
Cannot be scraped or peeled with a pocket knife; specimen can be fractured with single firm blow of geological hammer
25-50 3,500-7,000
R4 Strong rock Specimen requires more than one blow of geological hammer to fracture it
50-100 7,000-15,000
R5 Very strong rock Specimen requires many blows of geological hammer to fracture it
100-250 15,000-36,000
R6 Extremely strong rock
Specimen can only be chipped with geological hammer
>250 >36,000
Note: Grades S1 to S6 apply to cohesive soils, for example clays, silty clays, and combinations of silts and clays with
sand, generally slow draining. Discontinuity wall strength will generally be characterized by grades R0-R6 (rock) while S1-S6 (clay) will generally apply to filled discontinuities.
1 International Society for Rock Mechanics (ISRM), Commission on standardization of laboratory and field tests (1978): Suggested
methods for the quantitative description of discontinuities in rock masses. Int. J. Rock Mech. Min. Sci. & Geomech. Abstr., Vol. 15, No. 6, pp. 319-368.
S1: 1.0 ft - 3.0 ft, A-1-b, Top 4": Wet GRAVEL.Bottom 11.5": Grey-brown, wet, very dense, gravelly, fine tocoarse SAND, little silt, (SM), (FILL), Rec. = 1.3 ft
S2: 5.0 ft - 7.0 ft, A-4, Grey-brown, wet, medium dense, SILT,some fine to coarse sand, trace gravel towards top of sample,(ML), (FILL), Rec. = 0.75 ft
S3: 10.0 ft - 12.0 ft, A-4, Tan/grey, wet, medium dense, silty,fine to coarse SAND, trace gravel. Grey silt concentrated inpockets within the tan silty sand, (SM), (FILL). PP: 2.0 TSF,Rec. = 1.5 ft
S4: 15.0 ft - 17.0 ft, A-4, Tan-grey, some mottling, wet, verystiff, silty fine to coarse SAND, little gravel. Sample is sandierat top than bottom, (SM), (FILL), Rec. = 1.1 ft
S5: 20.0 ft - 22.0 ft, A-4, Light grey with pockets of darker greymaterial, moist, stiff, SILT, some fine to coarse sand, someclay, trace gravel, (ML), (FILL)., Rec. = 1.0 ft
12.8
13.5
11.5
11.8
14.4
30.2
30.8
37.9
30.8
25.2
16.5
58.3
49.0
45.9
64.8
35-34-19-20
(53)
9-10-7-10(17)
11-13-12-10
(25)
5-9-7-9(16)
8-7-6-7(13)
53.3
10.9
13.1
23.3
10.0
STATE OF VERMONTAGENCY OF TRANSPORTATION
MATERIALS & RESEARCH SECTIONSUBSURFACE INFORMATION
DEPTH(ft)
BORING NUMBER: B-401SHEET 1 of 3DATE STARTED: 3/08/17DATE COMPLETED: 3/20/17
SYMBOL
BORING TYPE: WASH BORESAMPLE TYPE: SPLIT BARRELHAMMER TYPE: AUTOCHECKED BY: JDL
PROJECT NUMBER: GAI 1668897SITE NUMBER: -GROUND ELEVATION: 854'GROUNDWATER DEPTH: 10.7' 3/20/17PROJECT PIN NUMBER: -
PROJECT NAME: Newport City STP 134-3(22)SITE NAME: Route 191 LandslideSTATION: 111 + 40OFFSET: 17.2' RTVTSPG:
2.5
5.0
7.5
10.0
12.5
15.0
17.5
20.0
22.5
BORING CREW: VTransDRILLER: Harold GarrowLOGGER: Laura McKeownBORING RIG: CME-55 Track
CLASSIFICATION OF MATERIALS(Description)
LOG
OF
BO
RIN
G &
WE
LL 2
017
NE
WP
OR
T.G
PJ
VT
AO
T.G
DT
7/
25/1
7
AASHTOGRAVEL
(%)
AASHTOSAND
(%)
AASHTOFINES
(%)
M.C.(%)
BLOWSPER 6 IN
(N VALUE)
Top of Well Elevation: 854.0 ft
WELLDIAGRAM
S6: 25.0 ft - 27.0 ft, A-4, Tan with pockets of dark greymaterial, some mottling, wet, stiff, fine to coarse sandy SILT,trace gravel, (ML), Rec. = 1.2 ft
S7: 30.0 ft - 32.0 ft, A-4, Tan with dark brown seams, wet,medium stiff, silty fine to coarse SAND, trace gravel, traceorganic wood fibres in dark brown seams, (SM). PP: 2.0 TSF,Rec. = 1.2 ft
S8: 35.0 ft - 37.0 ft, No recovery, Rec. = 0.0 ft
S9: 40.0 ft - 42.0 ft, A-7-6, Grey, moist, very stiff, silty CLAY,little fine to coarse sand, trace gravel, (CL). PP: 4.5, 4.5 TSF,Rec. = 1.4 ft
S10: 45.0 ft - 47.0 ft, A-4, Grey with pockets of tan material,moist, hard, SILT, little fine to coarse sand, trace gravel, (ML).PP > 4.5 TSF; TV: 2.4 TSF, Rec. = 1.1 ft
14.0
33.9
23.6
16.1
35.4
42.9
11.5
18.2
53.6
46.8
82.8
70.9
8-5-6-7(11)
5-3-3-4(6)
11-4-3-4(7)
6-6-10-28(16)
12-41-50/3"(R)
11.0
10.3
5.7
10.9
STATE OF VERMONTAGENCY OF TRANSPORTATION
MATERIALS & RESEARCH SECTIONSUBSURFACE INFORMATION
DEPTH(ft)
BORING NUMBER: B-401SHEET 2 of 3DATE STARTED: 3/08/17DATE COMPLETED: 3/20/17
SYMBOL
BORING TYPE: WASH BORESAMPLE TYPE: SPLIT BARRELHAMMER TYPE: AUTOCHECKED BY: JDL
PROJECT NUMBER: GAI 1668897SITE NUMBER: -GROUND ELEVATION: 854'GROUNDWATER DEPTH: 10.7' 3/20/17PROJECT PIN NUMBER: -
PROJECT NAME: Newport City STP 134-3(22)SITE NAME: Route 191 LandslideSTATION: 111 + 40OFFSET: 17.2' RTVTSPG:
27.5
30.0
32.5
35.0
37.5
40.0
42.5
45.0
47.5
BORING CREW: VTransDRILLER: Harold GarrowLOGGER: Laura McKeownBORING RIG: CME-55 Track
CLASSIFICATION OF MATERIALS(Description)
LOG
OF
BO
RIN
G &
WE
LL 2
017
NE
WP
OR
T.G
PJ
VT
AO
T.G
DT
7/
25/1
7
AASHTOGRAVEL
(%)
AASHTOSAND
(%)
AASHTOFINES
(%)
M.C.(%)
BLOWSPER 6 IN
(N VALUE)
WELLDIAGRAM
S11: 50.0 ft - 52.0 ft, A-4, Grey, moist, hard, SILT, little clay,trace gravel, trace fine to coarse sand, (ML). PP: 4.0 TSF; TV:4.0 TSF, Rec. = 1.9 ft
Hole stopped @ 52.0 ft
Notes:- Pavement thickness: 0.45'.- Driller noted cobbles/boulders from 43.5' to 45'.- Drilling of B-401 completed 3:15 on 03/08/2017. Wellinstalled from 10:50 AM to 3:40 PM on 03/20/2017.- Water Levels: - 3.4' b.g.s. at 3:22 PM on 03/08/2017. - 32.1' b.g.s. at 11:02 AM on 03/20/2017. - 10.7' b.g.s. in well at 3:20 PM on 03/20/2017; Water rightbelow pavement around well.- Location approximate. Boring not surveyed. Ground surfaceelevation estimated from contours on plan.
22.9 5.9 88.28-18-20-26
(38)
5.9
STATE OF VERMONTAGENCY OF TRANSPORTATION
MATERIALS & RESEARCH SECTIONSUBSURFACE INFORMATION
DEPTH(ft)
BORING NUMBER: B-401SHEET 3 of 3DATE STARTED: 3/08/17DATE COMPLETED: 3/20/17
SYMBOL
BORING TYPE: WASH BORESAMPLE TYPE: SPLIT BARRELHAMMER TYPE: AUTOCHECKED BY: JDL
PROJECT NUMBER: GAI 1668897SITE NUMBER: -GROUND ELEVATION: 854'GROUNDWATER DEPTH: 10.7' 3/20/17PROJECT PIN NUMBER: -
PROJECT NAME: Newport City STP 134-3(22)SITE NAME: Route 191 LandslideSTATION: 111 + 40OFFSET: 17.2' RTVTSPG:
52.5
55.0
57.5
60.0
62.5
65.0
67.5
70.0
72.5
BORING CREW: VTransDRILLER: Harold GarrowLOGGER: Laura McKeownBORING RIG: CME-55 Track
CLASSIFICATION OF MATERIALS(Description)
LOG
OF
BO
RIN
G &
WE
LL 2
017
NE
WP
OR
T.G
PJ
VT
AO
T.G
DT
7/
25/1
7
AASHTOGRAVEL
(%)
AASHTOSAND
(%)
AASHTOFINES
(%)
M.C.(%)
BLOWSPER 6 IN
(N VALUE)
WELLDIAGRAM
S1: 0.0 ft - 2.0 ft, A-1-b, SS, Brown, stiff, fine to coarse SAND, somegravel, little silt, trace organics, (SM), (FILL). Sample frozen, Rec. = 1.3ft
S2: 5.0 ft - 7.0 ft, SS, No recovery, Rec. = 0.0 ft
S3: 10.0 ft - 12.0 ft, SS, No recovery, Rec. = 0.0 ft
S4: 15.0 ft - 17.0 ft, SS, No recovery, Rec. = 0.0 ft
S5: 17.0 ft - 19.0 ft, A-4, SS, Brown with some mottling, stiff, silty, fine tocoarse SAND, little gravel, (SM), Rec. = 1.1 ft
S6: 20.0 ft - 22.0 ft, SS, No recovery, Rec. = 0.0 ft
19.9
13.9
41.7
34.2
19.6
49.0
6-3-6-4(9)
3-5-4-4(9)
9-16-13-14
(29)
6-7-11-6(18)
12-10-3-4(13)
5-6-8-11(14)
38.7
16.8
STATE OF VERMONTAGENCY OF TRANSPORTATION
MATERIALS & RESEARCH SECTIONSUBSURFACE INFORMATION
DEPTH(ft)
BORING NUMBER: B-402SHEET 1 of 2DATE STARTED: 3/13/17DATE COMPLETED: 3/13/17
SYMBOL
BORING TYPE: WASH BORESAMPLE TYPE: SPLIT BARRELHAMMER TYPE: AUTOCHECKED BY: JDL
PROJECT NUMBER: GAI 1668897SITE NUMBER: -GROUND ELEVATION: 820'GROUNDWATER DEPTH: 0.9' 3/13/17PROJECT PIN NUMBER: -
PROJECT NAME: Newport City STP 134-3(22)SITE NAME: Route 191 LandslideSTATION: 111 + 40OFFSET: 103' RTVTSPG:
2.5
5.0
7.5
10.0
12.5
15.0
17.5
20.0
22.5
BORING CREW: VTransDRILLER: Harold GarrowLOGGER: Laura McKeownBORING RIG: CME-55 Track
CLASSIFICATION OF MATERIALS(Description)
LOG
OF
BO
RIN
G &
WE
LL 2
017
NE
WP
OR
T.G
PJ
VT
AO
T.G
DT
7/
25/1
7
AASHTOGRAVEL
(%)
AASHTOSAND
(%)
AASHTOFINES
(%)
M.C.(%)
BLOWSPER 6 IN
(N VALUE)
S7: 25.0 ft - 27.0 ft, A-6, SS, Grey, moist, very stiff, silty CLAY, tracegravel, trace fine to coarse sand, (CL-ML). PP: 1.25, 3.75 TSF, Rec. =1.4 ft
S8: 30.0 ft - 32.0 ft, A-4, SS, Grey, wet, very stiff, SILT, little fine tocoarse sand, little clay, trace gravel, (ML), Rec. = 1.6 ft
Hole stopped @ 32.0 ft
Notes:- Water at 0.9' b.g.s. in casing at 2:05 PM 03/13/2017. Water at sufacewhen casing removed.- Collapse back to 14.2' when casing removed.- Location approximate. Boring not surveyed. Ground surface elevationestimated from contours on plan.
26.9
16.3
1.8
18.4
96.6
71.8
5-9-17-15(26)
6-16-14-16
(30)
1.6
9.8
STATE OF VERMONTAGENCY OF TRANSPORTATION
MATERIALS & RESEARCH SECTIONSUBSURFACE INFORMATION
DEPTH(ft)
BORING NUMBER: B-402SHEET 2 of 2DATE STARTED: 3/13/17DATE COMPLETED: 3/13/17
SYMBOL
BORING TYPE: WASH BORESAMPLE TYPE: SPLIT BARRELHAMMER TYPE: AUTOCHECKED BY: JDL
PROJECT NUMBER: GAI 1668897SITE NUMBER: -GROUND ELEVATION: 820'GROUNDWATER DEPTH: 0.9' 3/13/17PROJECT PIN NUMBER: -
PROJECT NAME: Newport City STP 134-3(22)SITE NAME: Route 191 LandslideSTATION: 111 + 40OFFSET: 103' RTVTSPG:
27.5
30.0
32.5
35.0
37.5
40.0
42.5
45.0
47.5
BORING CREW: VTransDRILLER: Harold GarrowLOGGER: Laura McKeownBORING RIG: CME-55 Track
CLASSIFICATION OF MATERIALS(Description)
LOG
OF
BO
RIN
G &
WE
LL 2
017
NE
WP
OR
T.G
PJ
VT
AO
T.G
DT
7/
25/1
7
AASHTOGRAVEL
(%)
AASHTOSAND
(%)
AASHTOFINES
(%)
M.C.(%)
BLOWSPER 6 IN
(N VALUE)
S1: 0.0 ft - 2.0 ft, A-1-b, SS, Brown, moist, medium dense, fine to coarsesandy GRAVEL, some silt, trace organic material, (GM), (FILL), Rec. =1.0 ft
S2: 5.0 ft - 7.0 ft, A-2-4, SS, Top 0.2': Dark grey rock fragments,probable cobble.Bottom 0.9': Tan with some mottling, very dense, fine to medium SAND,some gravel, some silt, (SM), Rec. = 1.1 ft
S3: 10.0 ft - 12.0 ft, A-1-a, SS, Dark grey, wet, GRAVEL, some fine tocoarse sand, trace silt in spoon tip, (GP-GM). Probably broken upcobble/boulder, Rec. = 0.3 ft
S4: 15.0 ft - 17.0 ft, A-1-a, SS, Dark grey, dense, GRAVEL, some brownfine to coarse sand, little silt, (GM), Rec. = 0.7 ft
S5: 20.0 ft - 22.0 ft, SS, No recovery, Rec. = 0.0 ft
13.1
9.3
5.1
8.2
29.0
34.9
16.2
22.3
24.1
33.6
9.9
13.6
6-8-7-7(15)
14-43-29-20
(72)
50/5"(R)
24-18-21-22
(39)
20-15-21-27
(36)
46.9
31.5
73.9
64.1
STATE OF VERMONTAGENCY OF TRANSPORTATION
MATERIALS & RESEARCH SECTIONSUBSURFACE INFORMATION
DEPTH(ft)
BORING NUMBER: B-403SHEET 1 of 2DATE STARTED: 3/10/17DATE COMPLETED: 3/10/17
SYMBOL
BORING TYPE: WASH BORESAMPLE TYPE: SPLIT BARRELHAMMER TYPE: AUTOCHECKED BY: JDL
PROJECT NUMBER: GAI 1668897SITE NUMBER: -GROUND ELEVATION: 862'GROUNDWATER DEPTH: 1.3' 3/10/17PROJECT PIN NUMBER: -
PROJECT NAME: Newport City STP 134-3(22)SITE NAME: Route 191 LandslideSTATION: 109 + 18OFFSET: 55' RTVTSPG:
2.5
5.0
7.5
10.0
12.5
15.0
17.5
20.0
22.5
BORING CREW: VTransDRILLER: Harold GarrowLOGGER: Laura McKeownBORING RIG: CME-55 Track
CLASSIFICATION OF MATERIALS(Description)
LOG
OF
BO
RIN
G &
WE
LL 2
017
NE
WP
OR
T.G
PJ
VT
AO
T.G
DT
7/
25/1
7
AASHTOGRAVEL
(%)
AASHTOSAND
(%)
AASHTOFINES
(%)
M.C.(%)
BLOWSPER 6 IN
(N VALUE)
S6: 25.0 ft - 27.0 ft, A-6, SS, Grey , wet, hard, silty CLAY, trace gravel,trace sand, (CL). PP: 2.25, 4.25, >4.5 TSF; TV: 1.5, Rec. = 1.9 ft
S7: 30.0 ft - 32.0 ft, A-6, SS, Grey, wet, hard, silty CLAY, trace gravel,trace sand, (CL). PP: 3.25, 3.25, 3.75 TSF; TV: 4.5, Rec. = 2.0 ft
Hole stopped @ 32.0 ft
Notes:- Water at 1.3' b.g.s. in casing at 11:45 AM 03/10/2017.- Collapse back to 8.2' when casing removed.- Location approximate. Boring not surveyed. Ground surface elevationestimated from contours on plan.
21.2
23.2
4.0
5.6
90.8
91.8
14-21-24-28
(45)
11-18-26-31
(44)
5.2
2.6
STATE OF VERMONTAGENCY OF TRANSPORTATION
MATERIALS & RESEARCH SECTIONSUBSURFACE INFORMATION
DEPTH(ft)
BORING NUMBER: B-403SHEET 2 of 2DATE STARTED: 3/10/17DATE COMPLETED: 3/10/17
SYMBOL
BORING TYPE: WASH BORESAMPLE TYPE: SPLIT BARRELHAMMER TYPE: AUTOCHECKED BY: JDL
PROJECT NUMBER: GAI 1668897SITE NUMBER: -GROUND ELEVATION: 862'GROUNDWATER DEPTH: 1.3' 3/10/17PROJECT PIN NUMBER: -
PROJECT NAME: Newport City STP 134-3(22)SITE NAME: Route 191 LandslideSTATION: 109 + 18OFFSET: 55' RTVTSPG:
27.5
30.0
32.5
35.0
37.5
40.0
42.5
45.0
47.5
BORING CREW: VTransDRILLER: Harold GarrowLOGGER: Laura McKeownBORING RIG: CME-55 Track
CLASSIFICATION OF MATERIALS(Description)
LOG
OF
BO
RIN
G &
WE
LL 2
017
NE
WP
OR
T.G
PJ
VT
AO
T.G
DT
7/
25/1
7
AASHTOGRAVEL
(%)
AASHTOSAND
(%)
AASHTOFINES
(%)
M.C.(%)
BLOWSPER 6 IN
(N VALUE)
APPENDIX B LABORATORY TEST RESULTS
APPENDIX B-1 FROM 400-SERIES BORING SAMPLES
State of VermontAgency of Transportation
Construction and Materials BureauCentral Laboratory
Report on Soil Sample
Distribution list
Lab number: E170202 Corrected copy: N/A 4/12/2017 2:33:44 PReport Date:
Site: VT 191 SLIDEProject: NEWPORT Number: STP 1343(22)
Quantity:
Comment: Sample 1D
Received: 3/10/2017
Submitted by: Golder
Tested by: J. Daigneault
Station: 111+40 Offset: 18.0
Date sampled: 3/8/2017 Tested: 3/10/2017
Hole: B-401 Depth: 1 to: 3FT FT
Field description: Si Gr Sa, gry-brn, Moist
Address:
Sample type: Split Barrel
Sample source/Outside agency name:
Location used: Examined for: MC, GS
Test Results
Gr: 53.3%
Sa: 30.2%
Si: 16.5%
D2487: SM
M145: A-1-b
Reviewed by: Marcy L. Montague, PE, Senior Geotechnical Engineer
Sandy Gravel
Comments: Lab Note: Broken rock was within sample.
75 mm (3.0"):
37.5 mm (1.5"):
19 mm (3/4"): 94.9%
9.5 mm (3/8"): 74.3%
4.75 mm (#4): 61.7%
2.00 mm (#10): 46.7%
850 µm (#20): 35.3%
425 µm (#40): 27.6%
250 µm (#60): 23.0%
150 µm (#100): 20.5%
75 µm (#200): 16.5%
T-88 % Passing
Sieve Analysis
Total Sample
Hydrometer Analysis
Particles smaller % total sample
0.05 mm:
0.02 mm:
0.005 mm:
0.002 mm:
0.001 mm:
T-265 Moisture content: 12.8%
T-89 Liquid Limit:
T-90 Plastic Limit:
T-90 Plasticity Index: NP
Maximum density:
Optimum moisture:
Method:Test method: T-180
Limits
Moisture Density
pcf
T-100 Specific Gravity:
State of VermontAgency of Transportation
Construction and Materials BureauCentral Laboratory
Report on Soil Sample
Distribution list
Lab number: E170202 Corrected copy: N/A 4/12/2017 2:34:15 PReport Date:
Site: VT 191 SLIDEProject: NEWPORT Number: STP 1343(22)
Hole: B-401 Depth: 1 3FT FT-
T-88 Particle size analysis
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
0.010.1110100Particle size, mm
Pct smaller
State of VermontAgency of Transportation
Construction and Materials BureauCentral Laboratory
Report on Soil Sample
Distribution list
Lab number: E170203 Corrected copy: N/A 4/12/2017 2:33:47 PReport Date:
Site: VT 191 SLIDEProject: NEWPORT Number: STP 1343(22)
Quantity:
Comment: Sample 2D
Received: 3/10/2017
Submitted by: Golder
Tested by: J. Daigneault
Station: 111+40 Offset: 18.0
Date sampled: 3/8/2017 Tested: 3/10/2017
Hole: B-401 Depth: 5 to: 7FT FT
Field description: Gr Si Sa, gry, M
Address:
Sample type: Split Barrel
Sample source/Outside agency name:
Location used: Examined for: MC, GS
Test Results
Gr: 10.9%
Sa: 30.8%
Si: 58.3%
D2487: ML
M145: A-4
Reviewed by: Marcy L. Montague, PE, Senior Geotechnical Engineer
Sandy Silt
Comments:
75 mm (3.0"):
37.5 mm (1.5"):
19 mm (3/4"):
9.5 mm (3/8"): 95.9%
4.75 mm (#4): 93.3%
2.00 mm (#10): 89.1%
850 µm (#20): 84.5%
425 µm (#40): 79.6%
250 µm (#60): 74.6%
150 µm (#100): 69.1%
75 µm (#200): 58.3%
T-88 % Passing
Sieve Analysis
Total Sample
Hydrometer Analysis
Particles smaller % total sample
0.05 mm:
0.02 mm:
0.005 mm:
0.002 mm:
0.001 mm:
T-265 Moisture content: 13.5%
T-89 Liquid Limit:
T-90 Plastic Limit:
T-90 Plasticity Index: NP
Maximum density:
Optimum moisture:
Method:Test method: T-180
Limits
Moisture Density
pcf
T-100 Specific Gravity:
State of VermontAgency of Transportation
Construction and Materials BureauCentral Laboratory
Report on Soil Sample
Distribution list
Lab number: E170203 Corrected copy: N/A 4/12/2017 2:34:15 PReport Date:
Site: VT 191 SLIDEProject: NEWPORT Number: STP 1343(22)
Hole: B-401 Depth: 5 7FT FT-
T-88 Particle size analysis
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
0.010.1110100Particle size, mm
Pct smaller
State of VermontAgency of Transportation
Construction and Materials BureauCentral Laboratory
Report on Soil Sample
Distribution list
Lab number: E170204 Corrected copy: N/A 4/12/2017 2:33:47 PReport Date:
Site: VT 191 SLIDEProject: NEWPORT Number: STP 1343(22)
Quantity:
Comment: Sample 3D
Received: 3/10/2017
Submitted by: Golder
Tested by: J. Daigneault
Station: 111+40 Offset: 18.0
Date sampled: 3/8/2017 Tested: 3/10/2017
Hole: B-401 Depth: 10 to: 12FT FT
Field description: Gr Si Sa, tan-gry, Moist
Address:
Sample type: Split Barrel
Sample source/Outside agency name:
Location used: Examined for: MC, GS
Test Results
Gr: 13.1%
Sa: 38.0%
Si: 49.0%
D2487: SM
M145: A-4
Reviewed by: Marcy L. Montague, PE, Senior Geotechnical Engineer
Sandy Silt
Comments:
75 mm (3.0"):
37.5 mm (1.5"):
19 mm (3/4"): 98.4%
9.5 mm (3/8"): 95.6%
4.75 mm (#4): 91.9%
2.00 mm (#10): 86.9%
850 µm (#20): 81.3%
425 µm (#40): 74.1%
250 µm (#60): 66.5%
150 µm (#100): 60.0%
75 µm (#200): 49.0%
T-88 % Passing
Sieve Analysis
Total Sample
Hydrometer Analysis
Particles smaller % total sample
0.05 mm:
0.02 mm:
0.005 mm:
0.002 mm:
0.001 mm:
T-265 Moisture content: 11.5%
T-89 Liquid Limit:
T-90 Plastic Limit:
T-90 Plasticity Index: NP
Maximum density:
Optimum moisture:
Method:Test method: T-180
Limits
Moisture Density
pcf
T-100 Specific Gravity:
State of VermontAgency of Transportation
Construction and Materials BureauCentral Laboratory
Report on Soil Sample
Distribution list
Lab number: E170204 Corrected copy: N/A 4/12/2017 2:34:15 PReport Date:
Site: VT 191 SLIDEProject: NEWPORT Number: STP 1343(22)
Hole: B-401 Depth: 10 12FT FT-
T-88 Particle size analysis
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
0.010.1110100Particle size, mm
Pct smaller
State of VermontAgency of Transportation
Construction and Materials BureauCentral Laboratory
Report on Soil Sample
Distribution list
Lab number: E170205 Corrected copy: N/A 4/12/2017 2:33:47 PReport Date:
Site: VT 191 SLIDEProject: NEWPORT Number: STP 1343(22)
Quantity:
Comment: Sample 4D
Received: 3/10/2017
Submitted by: Golder
Tested by: J. Daigneault
Station: 111+40 Offset: 18.0
Date sampled: 3/8/2017 Tested: 3/10/2017
Hole: B-401 Depth: 15 to: 17FT FT
Field description: Gr Sa Clay Si, tan-gry, Wet
Address:
Sample type: Split Barrel
Sample source/Outside agency name:
Location used: Examined for: MC, GS
Test Results
Gr: 23.3%
Sa: 30.8%
Si: 45.9%
D2487: SM
M145: A-4
Reviewed by: Marcy L. Montague, PE, Senior Geotechnical Engineer
Gravelly Sandy Silt
Comments:
75 mm (3.0"):
37.5 mm (1.5"):
19 mm (3/4"): 88.5%
9.5 mm (3/8"): 84.9%
4.75 mm (#4): 80.7%
2.00 mm (#10): 76.7%
850 µm (#20): 71.1%
425 µm (#40): 66.1%
250 µm (#60): 61.1%
150 µm (#100): 55.4%
75 µm (#200): 45.9%
T-88 % Passing
Sieve Analysis
Total Sample
Hydrometer Analysis
Particles smaller % total sample
0.05 mm:
0.02 mm:
0.005 mm:
0.002 mm:
0.001 mm:
T-265 Moisture content: 11.8%
T-89 Liquid Limit:
T-90 Plastic Limit:
T-90 Plasticity Index: NP
Maximum density:
Optimum moisture:
Method:Test method: T-180
Limits
Moisture Density
pcf
T-100 Specific Gravity:
State of VermontAgency of Transportation
Construction and Materials BureauCentral Laboratory
Report on Soil Sample
Distribution list
Lab number: E170205 Corrected copy: N/A 4/12/2017 2:34:16 PReport Date:
Site: VT 191 SLIDEProject: NEWPORT Number: STP 1343(22)
Hole: B-401 Depth: 15 17FT FT-
T-88 Particle size analysis
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
0.010.1110100Particle size, mm
Pct smaller
State of VermontAgency of Transportation
Construction and Materials BureauCentral Laboratory
Report on Soil Sample
Distribution list
Lab number: E170206 Corrected copy: N/A 4/12/2017 2:33:47 PReport Date:
Site: VT 191 SLIDEProject: NEWPORT Number: STP 1343(22)
Quantity:
Comment: Sample 5D
Received: 3/10/2017
Submitted by: Golder
Tested by: J. Daigneault
Station: 111+40 Offset: 18.0
Date sampled: 3/8/2017 Tested: 3/10/2017
Hole: B-401 Depth: 20 to: 22FT FT
Field description: Sa Clay Si, gry, Moist
Address:
Sample type: Split Barrel
Sample source/Outside agency name:
Location used: Examined for: MC, GS, AL
Test Results
Gr: 10.0%
Sa: 25.2%
Si: 64.8%
D2487: ML
M145: A-4
Reviewed by: Marcy L. Montague, PE, Senior Geotechnical Engineer
Sandy Silt
Comments: Lab Note: Some clay was within sample. Sample tested non-plastic.
75 mm (3.0"):
37.5 mm (1.5"):
19 mm (3/4"):
9.5 mm (3/8"): 97.7%
4.75 mm (#4): 94.6%
2.00 mm (#10): 90.0%
850 µm (#20): 85.4%
425 µm (#40): 81.3%
250 µm (#60): 76.8%
150 µm (#100): 72.5%
75 µm (#200): 64.8%
T-88 % Passing
Sieve Analysis
Total Sample
Hydrometer Analysis
Particles smaller % total sample
0.05 mm:
0.02 mm:
0.005 mm:
0.002 mm:
0.001 mm:
T-265 Moisture content: 14.4%
T-89 Liquid Limit:
T-90 Plastic Limit:
T-90 Plasticity Index: NP
Maximum density:
Optimum moisture:
Method:Test method: T-180
Limits
Moisture Density
pcf
T-100 Specific Gravity:
State of VermontAgency of Transportation
Construction and Materials BureauCentral Laboratory
Report on Soil Sample
Distribution list
Lab number: E170206 Corrected copy: N/A 4/12/2017 2:34:16 PReport Date:
Site: VT 191 SLIDEProject: NEWPORT Number: STP 1343(22)
Hole: B-401 Depth: 20 22FT FT-
T-88 Particle size analysis
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
0.010.1110100Particle size, mm
Pct smaller
State of VermontAgency of Transportation
Construction and Materials BureauCentral Laboratory
Report on Soil Sample
Distribution list
Lab number: E170207 Corrected copy: N/A 4/12/2017 2:33:48 PReport Date:
Site: VT 191 SLIDEProject: NEWPORT Number: STP 1343(22)
Quantity:
Comment: Sample 6D
Received: 3/10/2017
Submitted by: Golder
Tested by: J. Daigneault
Station: 111+40 Offset: 18.0
Date sampled: 3/8/2017 Tested: 3/10/2017
Hole: B-401 Depth: 25 to: 27FT FT
Field description: Gr Sa Clay Si, tan-Dk/gry, Moist
Address:
Sample type: Split Barrel
Sample source/Outside agency name:
Location used: Examined for: MC, GS
Test Results
Gr: 11.0%
Sa: 35.4%
Si: 53.6%
D2487: ML
M145: A-4
Reviewed by: Marcy L. Montague, PE, Senior Geotechnical Engineer
Sandy Silt
Comments:
75 mm (3.0"):
37.5 mm (1.5"):
19 mm (3/4"):
9.5 mm (3/8"): 98.5%
4.75 mm (#4): 96.7%
2.00 mm (#10): 89.0%
850 µm (#20): 80.0%
425 µm (#40): 73.5%
250 µm (#60): 68.3%
150 µm (#100): 63.1%
75 µm (#200): 53.6%
T-88 % Passing
Sieve Analysis
Total Sample
Hydrometer Analysis
Particles smaller % total sample
0.05 mm:
0.02 mm:
0.005 mm:
0.002 mm:
0.001 mm:
T-265 Moisture content: 14.0%
T-89 Liquid Limit:
T-90 Plastic Limit:
T-90 Plasticity Index: NP
Maximum density:
Optimum moisture:
Method:Test method: T-180
Limits
Moisture Density
pcf
T-100 Specific Gravity:
State of VermontAgency of Transportation
Construction and Materials BureauCentral Laboratory
Report on Soil Sample
Distribution list
Lab number: E170207 Corrected copy: N/A 4/12/2017 2:34:16 PReport Date:
Site: VT 191 SLIDEProject: NEWPORT Number: STP 1343(22)
Hole: B-401 Depth: 25 27FT FT-
T-88 Particle size analysis
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
0.010.1110100Particle size, mm
Pct smaller
State of VermontAgency of Transportation
Construction and Materials BureauCentral Laboratory
Report on Soil Sample
Distribution list
Lab number: E170208 Corrected copy: N/A 4/12/2017 2:33:48 PReport Date:
Site: VT 191 SLIDEProject: NEWPORT Number: STP 1343(22)
Quantity:
Comment: Sample 8D
Received: 3/10/2017
Submitted by: Golder
Tested by: J. Daigneault
Station: 111+40 Offset: 18.0
Date sampled: 3/8/2017 Tested: 3/10/2017
Hole: B-401 Depth: 30 to: 32FT FT
Field description: Org. Sa Clay Si, tan-Dk/brn, Moist
Address:
Sample type: Split Barrel
Sample source/Outside agency name:
Location used: Examined for: MC, GS
Test Results
Gr: 10.3%
Sa: 43.0%
Si: 46.8%
D2487: SM
M145: A-4
Reviewed by: Marcy L. Montague, PE, Senior Geotechnical Engineer
Sandy Silt
Comments: Lab Note: A small amount of organic material was within sample.
75 mm (3.0"):
37.5 mm (1.5"):
19 mm (3/4"):
9.5 mm (3/8"): 97.4%
4.75 mm (#4): 94.4%
2.00 mm (#10): 89.7%
850 µm (#20): 81.3%
425 µm (#40): 73.8%
250 µm (#60): 66.7%
150 µm (#100): 59.9%
75 µm (#200): 46.8%
T-88 % Passing
Sieve Analysis
Total Sample
Hydrometer Analysis
Particles smaller % total sample
0.05 mm:
0.02 mm:
0.005 mm:
0.002 mm:
0.001 mm:
T-265 Moisture content: 33.9%
T-89 Liquid Limit:
T-90 Plastic Limit:
T-90 Plasticity Index: NP
Maximum density:
Optimum moisture:
Method:Test method: T-180
Limits
Moisture Density
pcf
T-100 Specific Gravity:
State of VermontAgency of Transportation
Construction and Materials BureauCentral Laboratory
Report on Soil Sample
Distribution list
Lab number: E170208 Corrected copy: N/A 4/12/2017 2:34:16 PReport Date:
Site: VT 191 SLIDEProject: NEWPORT Number: STP 1343(22)
Hole: B-401 Depth: 30 32FT FT-
T-88 Particle size analysis
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
0.010.1110100Particle size, mm
Pct smaller
State of VermontAgency of Transportation
Construction and Materials BureauCentral Laboratory
Report on Soil Sample
Distribution list
Lab number: E170209 Corrected copy: N/A 4/12/2017 2:33:48 PReport Date:
Site: VT 191 SLIDEProject: NEWPORT Number: STP 1343(22)
Quantity:
Comment: Sample 9D
Received: 3/10/2017
Submitted by: Golder
Tested by: J. Daigneault
Station: 111+40 Offset: 18.0
Date sampled: 3/8/2017 Tested: 3/10/2017
Hole: B-401 Depth: 40 to: 42FT FT
Field description: Si Clay, gry, Moist
Address:
Sample type: Split Barrel
Sample source/Outside agency name:
Location used: Examined for: MC, GS, AL
Test Results
Gr: 5.7%
Sa: 11.5%
Si: 82.8%
D2487: CL
M145: A-7-6
Reviewed by: Marcy L. Montague, PE, Senior Geotechnical Engineer
Silty Clay
Comments:
75 mm (3.0"):
37.5 mm (1.5"):
19 mm (3/4"):
9.5 mm (3/8"): 98.5%
4.75 mm (#4): 96.7%
2.00 mm (#10): 94.3%
850 µm (#20): 92.2%
425 µm (#40): 90.1%
250 µm (#60): 88.2%
150 µm (#100): 86.1%
75 µm (#200): 82.8%
T-88 % Passing
Sieve Analysis
Total Sample
Hydrometer Analysis
Particles smaller % total sample
0.05 mm:
0.02 mm:
0.005 mm:
0.002 mm:
0.001 mm:
T-265 Moisture content: 23.6%
T-89 Liquid Limit: 41
T-90 Plastic Limit: 24
T-90 Plasticity Index: 17
Maximum density:
Optimum moisture:
Method:Test method: T-180
Limits
Moisture Density
pcf
T-100 Specific Gravity:
State of VermontAgency of Transportation
Construction and Materials BureauCentral Laboratory
Report on Soil Sample
Distribution list
Lab number: E170209 Corrected copy: N/A 4/12/2017 2:34:16 PReport Date:
Site: VT 191 SLIDEProject: NEWPORT Number: STP 1343(22)
Hole: B-401 Depth: 40 42FT FT-
T-88 Particle size analysis
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
0.010.1110100Particle size, mm
Pct smaller
State of VermontAgency of Transportation
Construction and Materials BureauCentral Laboratory
Report on Soil Sample
Distribution list
Lab number: E170210 Corrected copy: N/A 4/12/2017 2:33:48 PReport Date:
Site: VT 191 SLIDEProject: NEWPORT Number: STP 1343(22)
Quantity:
Comment: Sample 10D
Received: 3/10/2017
Submitted by: Golder
Tested by: J. Daigneault
Station: 111+40 Offset: 18.0
Date sampled: 3/8/2017 Tested: 3/10/2017
Hole: B-401 Depth: 45 to: 46.3FT FT
Field description: Sa Si, gry-tan, M
Address:
Sample type: Split Barrel
Sample source/Outside agency name:
Location used: Examined for: MC, GS
Test Results
Gr: 10.9%
Sa: 18.2%
Si: 70.9%
D2487: ML
M145: A-4
Reviewed by: Marcy L. Montague, PE, Senior Geotechnical Engineer
Silt
Comments:
75 mm (3.0"):
37.5 mm (1.5"):
19 mm (3/4"): 97.1%
9.5 mm (3/8"): 93.5%
4.75 mm (#4): 91.3%
2.00 mm (#10): 89.1%
850 µm (#20): 85.8%
425 µm (#40): 82.2%
250 µm (#60): 78.7%
150 µm (#100): 75.9%
75 µm (#200): 70.9%
T-88 % Passing
Sieve Analysis
Total Sample
Hydrometer Analysis
Particles smaller % total sample
0.05 mm:
0.02 mm:
0.005 mm:
0.002 mm:
0.001 mm:
T-265 Moisture content: 16.1%
T-89 Liquid Limit:
T-90 Plastic Limit:
T-90 Plasticity Index: NP
Maximum density:
Optimum moisture:
Method:Test method: T-180
Limits
Moisture Density
pcf
T-100 Specific Gravity:
State of VermontAgency of Transportation
Construction and Materials BureauCentral Laboratory
Report on Soil Sample
Distribution list
Lab number: E170210 Corrected copy: N/A 4/12/2017 2:34:16 PReport Date:
Site: VT 191 SLIDEProject: NEWPORT Number: STP 1343(22)
Hole: B-401 Depth: 45 46.3FT FT-
T-88 Particle size analysis
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
0.010.1110100Particle size, mm
Pct smaller
State of VermontAgency of Transportation
Construction and Materials BureauCentral Laboratory
Report on Soil Sample
Distribution list
Lab number: E170211 Corrected copy: N/A 4/12/2017 2:33:49 PReport Date:
Site: VT 191 SLIDEProject: NEWPORT Number: STP 1343(22)
Quantity:
Comment: Sample 11D
Received: 3/10/2017
Submitted by: Golder
Tested by: J. Daigneault
Station: 111+40 Offset: 18.0
Date sampled: 3/8/2017 Tested: 3/10/2017
Hole: B-401 Depth: 50 to: 52FT FT
Field description: Sa Clay Si, gry, M
Address:
Sample type: Split Barrel
Sample source/Outside agency name:
Location used: Examined for: MC, GS
Test Results
Gr: 5.9%
Sa: 5.9%
Si: 88.2%
D2487: ML
M145: A-4
Reviewed by: Marcy L. Montague, PE, Senior Geotechnical Engineer
Silt
Comments:
75 mm (3.0"):
37.5 mm (1.5"):
19 mm (3/4"): 96.4%
9.5 mm (3/8"): 95.1%
4.75 mm (#4): 94.8%
2.00 mm (#10): 94.1%
850 µm (#20): 93.0%
425 µm (#40): 92.1%
250 µm (#60): 91.2%
150 µm (#100): 90.1%
75 µm (#200): 88.2%
T-88 % Passing
Sieve Analysis
Total Sample
Hydrometer Analysis
Particles smaller % total sample
0.05 mm:
0.02 mm:
0.005 mm:
0.002 mm:
0.001 mm:
T-265 Moisture content: 22.9%
T-89 Liquid Limit:
T-90 Plastic Limit:
T-90 Plasticity Index: NP
Maximum density:
Optimum moisture:
Method:Test method: T-180
Limits
Moisture Density
pcf
T-100 Specific Gravity:
State of VermontAgency of Transportation
Construction and Materials BureauCentral Laboratory
Report on Soil Sample
Distribution list
Lab number: E170211 Corrected copy: N/A 4/12/2017 2:34:16 PReport Date:
Site: VT 191 SLIDEProject: NEWPORT Number: STP 1343(22)
Hole: B-401 Depth: 50 52FT FT-
T-88 Particle size analysis
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
0.010.1110100Particle size, mm
Pct smaller
State of VermontAgency of Transportation
Construction and Materials BureauCentral Laboratory
Report on Soil Sample
Distribution list
Lab number: E170218 Corrected copy: N/A 4/12/2017 3:02:02 PReport Date:
Site: VT 191 SLIDEProject: NEWPORT Number: STP 1343(22)
Quantity:
Comment: Sample 1D
Received: 3/20/2017
Submitted by: Golder
Tested by: J. Daigneault
Station: 111+40 Offset: 103
Date sampled: 3/13/2017 Tested: 3/20/2017
Hole: B-402 Depth: 0 to: 2FT FT
Field description: Org. Gr Sa Si, Dk/brn, Moist
Address:
Sample type: Split Barrel
Sample source/Outside agency name:
Location used: Examined for: MC, GS
Test Results
Gr: 38.7%
Sa: 41.7%
Si: 19.6%
D2487: SM
M145: A-1-b
Reviewed by: Marcy L. Montague, PE, Senior Geotechnical Engineer
Gravelly Sand
Comments: Lab Note: Asphalt pavement and plant material was within sample.
75 mm (3.0"):
37.5 mm (1.5"):
19 mm (3/4"):
9.5 mm (3/8"): 86.5%
4.75 mm (#4): 73.4%
2.00 mm (#10): 61.3%
850 µm (#20): 50.1%
425 µm (#40): 41.4%
250 µm (#60): 33.7%
150 µm (#100): 27.3%
75 µm (#200): 19.6%
T-88 % Passing
Sieve Analysis
Total Sample
Hydrometer Analysis
Particles smaller % total sample
0.05 mm:
0.02 mm:
0.005 mm:
0.002 mm:
0.001 mm:
T-265 Moisture content: 19.9%
T-89 Liquid Limit:
T-90 Plastic Limit:
T-90 Plasticity Index: NP
Maximum density:
Optimum moisture:
Method:Test method: T-180
Limits
Moisture Density
pcf
T-100 Specific Gravity:
State of VermontAgency of Transportation
Construction and Materials BureauCentral Laboratory
Report on Soil Sample
Distribution list
Lab number: E170218 Corrected copy: N/A 4/12/2017 3:03:02 PReport Date:
Site: VT 191 SLIDEProject: NEWPORT Number: STP 1343(22)
Hole: B-402 Depth: 0 2FT FT-
T-88 Particle size analysis
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
0.010.1110100Particle size, mm
Pct smaller
State of VermontAgency of Transportation
Construction and Materials BureauCentral Laboratory
Report on Soil Sample
Distribution list
Lab number: E170219 Corrected copy: N/A 4/12/2017 3:02:03 PReport Date:
Site: VT 191 SLIDEProject: NEWPORT Number: STP 1343(22)
Quantity:
Comment: Sample 5D
Received: 3/20/2017
Submitted by: Golder
Tested by: J. Daigneault
Station: 111+40 Offset: 103
Date sampled: 3/13/2017 Tested: 3/20/2017
Hole: B-402 Depth: 17 to: 19FT FT
Field description:
Address:
Sample type: Split Barrel
Sample source/Outside agency name:
Location used: Examined for: MC, GS
Test Results
Gr: 16.8%
Sa: 34.2%
Si: 49.0%
D2487: SM
M145: A-4
Reviewed by: Marcy L. Montague, PE, Senior Geotechnical Engineer
Sandy Silt
Comments:
75 mm (3.0"):
37.5 mm (1.5"):
19 mm (3/4"): 96.6%
9.5 mm (3/8"): 92.1%
4.75 mm (#4): 88.5%
2.00 mm (#10): 83.2%
850 µm (#20): 76.5%
425 µm (#40): 70.0%
250 µm (#60): 63.5%
150 µm (#100): 57.9%
75 µm (#200): 49.0%
T-88 % Passing
Sieve Analysis
Total Sample
Hydrometer Analysis
Particles smaller % total sample
0.05 mm:
0.02 mm:
0.005 mm:
0.002 mm:
0.001 mm:
T-265 Moisture content: 13.9%
T-89 Liquid Limit:
T-90 Plastic Limit:
T-90 Plasticity Index: NP
Maximum density:
Optimum moisture:
Method:Test method: T-180
Limits
Moisture Density
pcf
T-100 Specific Gravity:
State of VermontAgency of Transportation
Construction and Materials BureauCentral Laboratory
Report on Soil Sample
Distribution list
Lab number: E170219 Corrected copy: N/A 4/12/2017 3:03:03 PReport Date:
Site: VT 191 SLIDEProject: NEWPORT Number: STP 1343(22)
Hole: B-402 Depth: 17 19FT FT-
T-88 Particle size analysis
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
0.010.1110100Particle size, mm
Pct smaller
State of VermontAgency of Transportation
Construction and Materials BureauCentral Laboratory
Report on Soil Sample
Distribution list
Lab number: E170220 Corrected copy: N/A 4/12/2017 3:02:03 PReport Date:
Site: VT 191 SLIDEProject: NEWPORT Number: STP 1343(22)
Quantity:
Comment: Sample 7D
Received: 3/20/2017
Submitted by: Golder
Tested by: J. Daigneault
Station: 111+40 Offset: 103
Date sampled: 3/13/2017 Tested: 3/20/2017
Hole: B-402 Depth: 25 to: 27FT FT
Field description: Si Clay, gry, Moist
Address:
Sample type: Split Barrel
Sample source/Outside agency name:
Location used: Examined for: MC, GS, AL
Test Results
Gr: 1.6%
Sa: 1.8%
Si: 96.6%
D2487: ML
M145: A-6
Reviewed by: Marcy L. Montague, PE, Senior Geotechnical Engineer
Silty Clay
Comments:
75 mm (3.0"):
37.5 mm (1.5"):
19 mm (3/4"):
9.5 mm (3/8"): 99.5%
4.75 mm (#4): 99.0%
2.00 mm (#10): 98.4%
850 µm (#20): 98.1%
425 µm (#40): 97.8%
250 µm (#60): 97.6%
150 µm (#100): 97.2%
75 µm (#200): 96.6%
T-88 % Passing
Sieve Analysis
Total Sample
Hydrometer Analysis
Particles smaller % total sample
0.05 mm:
0.02 mm:
0.005 mm:
0.002 mm:
0.001 mm:
T-265 Moisture content: 26.9%
T-89 Liquid Limit: 35
T-90 Plastic Limit: 24
T-90 Plasticity Index: 11
Maximum density:
Optimum moisture:
Method:Test method: T-180
Limits
Moisture Density
pcf
T-100 Specific Gravity:
State of VermontAgency of Transportation
Construction and Materials BureauCentral Laboratory
Report on Soil Sample
Distribution list
Lab number: E170220 Corrected copy: N/A 4/12/2017 3:03:03 PReport Date:
Site: VT 191 SLIDEProject: NEWPORT Number: STP 1343(22)
Hole: B-402 Depth: 25 27FT FT-
T-88 Particle size analysis
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
0.010.1110100Particle size, mm
Pct smaller
State of VermontAgency of Transportation
Construction and Materials BureauCentral Laboratory
Report on Soil Sample
Distribution list
Lab number: E170221 Corrected copy: N/A 4/12/2017 3:02:03 PReport Date:
Site: VT 191 SLIDEProject: NEWPORT Number: STP 1343(22)
Quantity:
Comment: Sample 8D
Received: 3/20/2017
Submitted by: Golder
Tested by: J. Daigneault
Station: 111+40 Offset: 103
Date sampled: 3/13/2017 Tested: 3/20/2017
Hole: B-402 Depth: 30 to: 32FT FT
Field description: Clay Si, gry, Wet
Address:
Sample type: Split Barrel
Sample source/Outside agency name:
Location used: Examined for: MC, GS, AL
Test Results
Gr: 9.8%
Sa: 18.4%
Si: 71.8%
D2487: ML
M145: A-4
Reviewed by: Marcy L. Montague, PE, Senior Geotechnical Engineer
Silt
Comments: Lab Note: A small amount of clay was within sample. Sample tested non-plastic.
75 mm (3.0"):
37.5 mm (1.5"):
19 mm (3/4"): 96.1%
9.5 mm (3/8"): 94.0%
4.75 mm (#4): 92.6%
2.00 mm (#10): 90.2%
850 µm (#20): 88.1%
425 µm (#40): 85.7%
250 µm (#60): 82.4%
150 µm (#100): 78.9%
75 µm (#200): 71.8%
T-88 % Passing
Sieve Analysis
Total Sample
Hydrometer Analysis
Particles smaller % total sample
0.05 mm:
0.02 mm:
0.005 mm:
0.002 mm:
0.001 mm:
T-265 Moisture content: 16.3%
T-89 Liquid Limit:
T-90 Plastic Limit:
T-90 Plasticity Index: NP
Maximum density:
Optimum moisture:
Method:Test method: T-180
Limits
Moisture Density
pcf
T-100 Specific Gravity:
State of VermontAgency of Transportation
Construction and Materials BureauCentral Laboratory
Report on Soil Sample
Distribution list
Lab number: E170221 Corrected copy: N/A 4/12/2017 3:03:03 PReport Date:
Site: VT 191 SLIDEProject: NEWPORT Number: STP 1343(22)
Hole: B-402 Depth: 30 32FT FT-
T-88 Particle size analysis
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
0.010.1110100Particle size, mm
Pct smaller
State of VermontAgency of Transportation
Construction and Materials BureauCentral Laboratory
Report on Soil Sample
Distribution list
Lab number: E170212 Corrected copy: N/A 4/12/2017 3:04:55 PReport Date:
Site: VT 191 SLIDEProject: NEWPORT Number: STP 1343(22)
Quantity:
Comment: Sample 1D
Received: 3/20/2017
Submitted by: Golder
Tested by: J. Daigneault
Station: 109+18 Offset: 55
Date sampled: 3/10/2017 Tested: 3/20/2017
Hole: B-403 Depth: 0 to: 2FT FT
Field description: Gr Si Sa, brn, M
Address:
Sample type: Split Barrel
Sample source/Outside agency name:
Location used: Examined for: MC, GS
Test Results
Gr: 46.9%
Sa: 28.9%
Si: 24.1%
D2487: GM
M145: A-1-b
Reviewed by: Marcy L. Montague, PE, Senior Geotechnical Engineer
Silty Sandy Gravel
Comments: Lab Note: Broken rock, grass, grass roots, and plant material were within sample.
75 mm (3.0"):
37.5 mm (1.5"):
19 mm (3/4"): 76.5%
9.5 mm (3/8"): 66.6%
4.75 mm (#4): 59.9%
2.00 mm (#10): 53.1%
850 µm (#20): 45.7%
425 µm (#40): 39.3%
250 µm (#60): 34.0%
150 µm (#100): 29.9%
75 µm (#200): 24.1%
T-88 % Passing
Sieve Analysis
Total Sample
Hydrometer Analysis
Particles smaller % total sample
0.05 mm:
0.02 mm:
0.005 mm:
0.002 mm:
0.001 mm:
T-265 Moisture content: 13.1%
T-89 Liquid Limit:
T-90 Plastic Limit:
T-90 Plasticity Index: NP
Maximum density:
Optimum moisture:
Method:Test method: T-180
Limits
Moisture Density
pcf
T-100 Specific Gravity:
State of VermontAgency of Transportation
Construction and Materials BureauCentral Laboratory
Report on Soil Sample
Distribution list
Lab number: E170212 Corrected copy: N/A 4/12/2017 3:05:16 PReport Date:
Site: VT 191 SLIDEProject: NEWPORT Number: STP 1343(22)
Hole: B-403 Depth: 0 2FT FT-
T-88 Particle size analysis
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
0.010.1110100Particle size, mm
Pct smaller
State of VermontAgency of Transportation
Construction and Materials BureauCentral Laboratory
Report on Soil Sample
Distribution list
Lab number: E170213 Corrected copy: N/A 4/12/2017 3:04:55 PReport Date:
Site: VT 191 SLIDEProject: NEWPORT Number: STP 1343(22)
Quantity:
Comment: Sample 2D
Received: 3/20/2017
Submitted by: Golder
Tested by: J. Daigneault
Station: 109+18 Offset: 55
Date sampled: 3/10/2017 Tested: 3/20/2017
Hole: B-403 Depth: 5 to: 7FT FT
Field description: Gr Si Sa, tan, M
Address:
Sample type: Split Barrel
Sample source/Outside agency name:
Location used: Examined for: MC, GS
Test Results
Gr: 31.5%
Sa: 34.9%
Si: 33.6%
D2487: SM
M145: A-2-4
Reviewed by: Marcy L. Montague, PE, Senior Geotechnical Engineer
Gravelly Silty Sand
Comments: Lab Note: Broken rock was within sample.
75 mm (3.0"):
37.5 mm (1.5"):
19 mm (3/4"): 87.9%
9.5 mm (3/8"): 82.1%
4.75 mm (#4): 75.3%
2.00 mm (#10): 68.5%
850 µm (#20): 61.3%
425 µm (#40): 55.1%
250 µm (#60): 48.6%
150 µm (#100): 42.6%
75 µm (#200): 33.6%
T-88 % Passing
Sieve Analysis
Total Sample
Hydrometer Analysis
Particles smaller % total sample
0.05 mm:
0.02 mm:
0.005 mm:
0.002 mm:
0.001 mm:
T-265 Moisture content: 9.3%
T-89 Liquid Limit:
T-90 Plastic Limit:
T-90 Plasticity Index: NP
Maximum density:
Optimum moisture:
Method:Test method: T-180
Limits
Moisture Density
pcf
T-100 Specific Gravity:
State of VermontAgency of Transportation
Construction and Materials BureauCentral Laboratory
Report on Soil Sample
Distribution list
Lab number: E170213 Corrected copy: N/A 4/12/2017 3:05:17 PReport Date:
Site: VT 191 SLIDEProject: NEWPORT Number: STP 1343(22)
Hole: B-403 Depth: 5 7FT FT-
T-88 Particle size analysis
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
0.010.1110100Particle size, mm
Pct smaller
State of VermontAgency of Transportation
Construction and Materials BureauCentral Laboratory
Report on Soil Sample
Distribution list
Lab number: E170214 Corrected copy: N/A 4/12/2017 3:04:56 PReport Date:
Site: VT 191 SLIDEProject: NEWPORT Number: STP 1343(22)
Quantity:
Comment: Sample 3D
Received: 3/20/2017
Submitted by: Golder
Tested by: J. Daigneault
Station: 109+18 Offset: 55
Date sampled: 3/10/2017 Tested: 3/20/2017
Hole: B-403 Depth: 10 to: 12FT FT
Field description: Si Gr, gry, Moist
Address:
Sample type: Split Barrel
Sample source/Outside agency name:
Location used: Examined for: MC, GS
Test Results
Gr: 73.9%
Sa: 16.2%
Si: 9.9%
D2487: GP-GM
M145: A-1-a
Reviewed by: Marcy L. Montague, PE, Senior Geotechnical Engineer
Gravel
Comments: Lab Note: Broken rock was within sample.
75 mm (3.0"):
37.5 mm (1.5"):
19 mm (3/4"): 47.3%
9.5 mm (3/8"): 42.8%
4.75 mm (#4): 33.8%
2.00 mm (#10): 26.1%
850 µm (#20): 19.1%
425 µm (#40): 15.5%
250 µm (#60): 13.7%
150 µm (#100): 12.4%
75 µm (#200): 9.9%
T-88 % Passing
Sieve Analysis
Total Sample
Hydrometer Analysis
Particles smaller % total sample
0.05 mm:
0.02 mm:
0.005 mm:
0.002 mm:
0.001 mm:
T-265 Moisture content: 5.1%
T-89 Liquid Limit:
T-90 Plastic Limit:
T-90 Plasticity Index: NP
Maximum density:
Optimum moisture:
Method:Test method: T-180
Limits
Moisture Density
pcf
T-100 Specific Gravity:
State of VermontAgency of Transportation
Construction and Materials BureauCentral Laboratory
Report on Soil Sample
Distribution list
Lab number: E170214 Corrected copy: N/A 4/12/2017 3:05:17 PReport Date:
Site: VT 191 SLIDEProject: NEWPORT Number: STP 1343(22)
Hole: B-403 Depth: 10 12FT FT-
T-88 Particle size analysis
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
0.010.1110100Particle size, mm
Pct smaller
State of VermontAgency of Transportation
Construction and Materials BureauCentral Laboratory
Report on Soil Sample
Distribution list
Lab number: E170215 Corrected copy: N/A 4/12/2017 3:04:56 PReport Date:
Site: VT 191 SLIDEProject: NEWPORT Number: STP 1343(22)
Quantity:
Comment: Sample 4D
Received: 3/20/2017
Submitted by: Golder
Tested by: J. Daigneault
Station: 109+18 Offset: 55
Date sampled: 3/10/2017 Tested: 3/20/2017
Hole: B-403 Depth: 15 to: 17FT FT
Field description: Si Sa Gr, gry-brn, Moist
Address:
Sample type: Split Barrel
Sample source/Outside agency name:
Location used: Examined for: MC, GS
Test Results
Gr: 64.1%
Sa: 22.3%
Si: 13.6%
D2487: GM
M145: A-1-a
Reviewed by: Marcy L. Montague, PE, Senior Geotechnical Engineer
Sandy Gravel
Comments: Lab Note: Broken rock was within sample.
75 mm (3.0"):
37.5 mm (1.5"):
19 mm (3/4"): 69.0%
9.5 mm (3/8"): 56.6%
4.75 mm (#4): 44.8%
2.00 mm (#10): 35.9%
850 µm (#20): 28.8%
425 µm (#40): 24.0%
250 µm (#60): 20.6%
150 µm (#100): 17.9%
75 µm (#200): 13.6%
T-88 % Passing
Sieve Analysis
Total Sample
Hydrometer Analysis
Particles smaller % total sample
0.05 mm:
0.02 mm:
0.005 mm:
0.002 mm:
0.001 mm:
T-265 Moisture content: 8.2%
T-89 Liquid Limit:
T-90 Plastic Limit:
T-90 Plasticity Index: NP
Maximum density:
Optimum moisture:
Method:Test method: T-180
Limits
Moisture Density
pcf
T-100 Specific Gravity:
State of VermontAgency of Transportation
Construction and Materials BureauCentral Laboratory
Report on Soil Sample
Distribution list
Lab number: E170215 Corrected copy: N/A 4/12/2017 3:05:17 PReport Date:
Site: VT 191 SLIDEProject: NEWPORT Number: STP 1343(22)
Hole: B-403 Depth: 15 17FT FT-
T-88 Particle size analysis
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
0.010.1110100Particle size, mm
Pct smaller
State of VermontAgency of Transportation
Construction and Materials BureauCentral Laboratory
Report on Soil Sample
Distribution list
Lab number: E170216 Corrected copy: N/A 4/12/2017 3:04:56 PReport Date:
Site: VT 191 SLIDEProject: NEWPORT Number: STP 1343(22)
Quantity:
Comment: Sample 6D
Received: 3/20/2017
Submitted by: Golder
Tested by: J. Daigneault
Station: 109+18 Offset: 55
Date sampled: 3/10/2017 Tested: 3/20/2017
Hole: B-403 Depth: 25 to: 27FT FT
Field description: Si Clay, gry, Wet
Address:
Sample type: Split Barrel
Sample source/Outside agency name:
Location used: Examined for: MC, GS, AL
Test Results
Gr: 5.2%
Sa: 3.9%
Si: 90.8%
D2487: CL
M145: A-6
Reviewed by: Marcy L. Montague, PE, Senior Geotechnical Engineer
Silty Clay
Comments:
75 mm (3.0"):
37.5 mm (1.5"):
19 mm (3/4"):
9.5 mm (3/8"): 97.7%
4.75 mm (#4): 96.2%
2.00 mm (#10): 94.8%
850 µm (#20): 93.9%
425 µm (#40): 93.3%
250 µm (#60): 92.8%
150 µm (#100): 92.2%
75 µm (#200): 90.8%
T-88 % Passing
Sieve Analysis
Total Sample
Hydrometer Analysis
Particles smaller % total sample
0.05 mm:
0.02 mm:
0.005 mm:
0.002 mm:
0.001 mm:
T-265 Moisture content: 21.2%
T-89 Liquid Limit: 32
T-90 Plastic Limit: 20
T-90 Plasticity Index: 12
Maximum density:
Optimum moisture:
Method:Test method: T-180
Limits
Moisture Density
pcf
T-100 Specific Gravity:
State of VermontAgency of Transportation
Construction and Materials BureauCentral Laboratory
Report on Soil Sample
Distribution list
Lab number: E170216 Corrected copy: N/A 4/12/2017 3:05:17 PReport Date:
Site: VT 191 SLIDEProject: NEWPORT Number: STP 1343(22)
Hole: B-403 Depth: 25 27FT FT-
T-88 Particle size analysis
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
0.010.1110100Particle size, mm
Pct smaller
State of VermontAgency of Transportation
Construction and Materials BureauCentral Laboratory
Report on Soil Sample
Distribution list
Lab number: E170217 Corrected copy: N/A 4/12/2017 3:04:56 PReport Date:
Site: VT 191 SLIDEProject: NEWPORT Number: STP 1343(22)
Quantity:
Comment: Sample 7D
Received: 3/20/2017
Submitted by: Golder
Tested by: J. Daigneault
Station: 109+18 Offset: 55
Date sampled: 3/10/2017 Tested: 3/20/2017
Hole: B-403 Depth: 30 to: 32FT FT
Field description: Sa Si Clay, gry, Wet
Address:
Sample type: Split Barrel
Sample source/Outside agency name:
Location used: Examined for: MC, GS, AL
Test Results
Gr: 2.6%
Sa: 5.6%
Si: 91.8%
D2487: CL
M145: A-6
Reviewed by: Marcy L. Montague, PE, Senior Geotechnical Engineer
Silty Clay
Comments:
75 mm (3.0"):
37.5 mm (1.5"):
19 mm (3/4"):
9.5 mm (3/8"): 98.8%
4.75 mm (#4): 98.2%
2.00 mm (#10): 97.4%
850 µm (#20): 96.4%
425 µm (#40): 95.3%
250 µm (#60): 94.2%
150 µm (#100): 93.3%
75 µm (#200): 91.8%
T-88 % Passing
Sieve Analysis
Total Sample
Hydrometer Analysis
Particles smaller % total sample
0.05 mm:
0.02 mm:
0.005 mm:
0.002 mm:
0.001 mm:
T-265 Moisture content: 23.2%
T-89 Liquid Limit: 37
T-90 Plastic Limit: 22
T-90 Plasticity Index: 15
Maximum density:
Optimum moisture:
Method:Test method: T-180
Limits
Moisture Density
pcf
T-100 Specific Gravity:
State of VermontAgency of Transportation
Construction and Materials BureauCentral Laboratory
Report on Soil Sample
Distribution list
Lab number: E170217 Corrected copy: N/A 4/12/2017 3:05:17 PReport Date:
Site: VT 191 SLIDEProject: NEWPORT Number: STP 1343(22)
Hole: B-403 Depth: 30 32FT FT-
T-88 Particle size analysis
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
0.010.1110100Particle size, mm
Pct smaller
APPENDIX B-2 200- AND 300-SERIES BORING SIEVE ANALYSES
USED FOR EXTRACTION WELL DESIGN
APPENDIX C GROUNDWATER MODELING
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1.0 CONCEPTUAL GEOLOGIC/HYDROGEOLOGIC MODEL The conceptual hydrogeologic model of the Newport Landslide Site is controlled by recharge areas, varying
lithologies and regional discharge. Percolating precipitation becomes groundwater in the recharge areas
south and southwest of the site (hill occupied by a golf course and slopes to the northeast) and moves
generally to the northeast towards the Clyde River and the abandoned power canal through the glacial
sediments. Groundwater movement occurs predominantly in the coarser glacial sediments (i.e., gravels,
sands and silts) which dip gently to the northeast. Some groundwater recharges the underlying bedrock
from the glacial sediments in the recharge areas, and there it also moves generally to the northeast,
eventually discharging to the Clyde River. The groundwater within the bedrock flows through a secondary
porosity developed from the joints, fractures and foliation plane openings present within the bedrock.
Primary porosity is likely not an important factor in groundwater flow in bedrock as the spaces between
primary grains (fine-grained biotite, muscovite, quartz and calcite crystals) have been filled with silica,
carbonate and other precipitated cement minerals through the processes of diagenesis and low-grade
metamorphism. Precipitation is also collected and stored by embankment fills associated with construction
of Route 191.
Groundwater, originating as precipitation recharge in the hill and slopes, flows initially downward vertically,
then subvertically and subhorizontally to the northeast through the glacial sediments and bedrock units.
This downward component is due to higher hydraulic head existing in the upper portion of the hill and slopes
than at depth. The Lower Sands and Gravels, being the thickest of the coarser glacial sediments, likely
carries the majority of groundwater within the unconsolidated glacial deposits. Groundwater then flows
beneath Route 191 through the glacial sediments and bedrock with a slight downward vertical component.
Shallow groundwater perched on the Upper Silts and Clays reaches the land surface in springs between
the stability berm and the abandoned power canal, often creating saturated surface conditions. This
shallow groundwater then enters the power canal. Deeper groundwater flows beneath the power canal
horizontally, then with an upward vertical component between the power canal and the Clyde River,
eventually flowing subvertically in very strong upward vertical gradients and discharging to the river.
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2.0 NUMERICAL GROUNDWATER MODEL
2.1 Introduction Numerical modeling was completed primarily to evaluate potential groundwater extraction scenarios and
their impact on reducing landslide movement. The following discussions provide a description of the
groundwater numerical model developed for the project.
To develop the framework for the numerical groundwater model, the three-dimensional geologic modeling
software platform EVS/MVS1 was used to construct a three-dimensional geologic model of the region
containing the landslide site. This visualization tool using kriging algorithms to statistically estimate the
stratigraphic correlations between boreholes, and a digital elevation model of the ground surface, was used
to construct a three-dimensional geologic model of the site. The results of the EVS/MVS model can then
be exported as direct input as the baseline geometry of the numerical groundwater model.
The numerical modeling code used to develop the numerical model was the United States Geological
Survey Modular Three-Dimensional Finite-Difference Groundwater Flow Model (MODFLOW2,3).
MODFLOW is a modular three-dimensional finite-difference groundwater flow model code that uses
numerical solutions of the equation governing groundwater flow through porous media. This code was
selected because: its flexibility allows for extensive calibration and sensitivity analysis; it can be used for
steady state and transient simulations; and it is generally considered to be one of the most reliable, verified
and commonly used groundwater flow models available. The pre- and post-processing software used for
the modeling was Groundwater Vistas Version 64.
The following discussions present the model approach, design assumptions, calibration, verification,
sensitivity analysis, and results.
2.2 Approach Development of a numerical groundwater flow model involves the following steps:
Definition of the model geometry including lateral and vertical extent, number of model layers, grid layout, location of recharge and discharge areas, rivers and streams
Selection of input parameters such as hydraulic conductivity (horizontal and vertical) and precipitation/evapotranspiration
1 C Tech Development Corporation, 2008. EVS/MVS Mining Visualization System, Vers. 9.6. 2 McDonald, M.G., and Harbaugh, A.W., 1988. A Modular Three-Dimensional Finite-Difference Groundwater Flow Model. Techniques of Water-Resources Investigations of the United States Geological Survey, Book 6, Chapter A1, U.S. Government Printing Office, Washington D.C. 3 Harbaugh, A.W., Banta, E.R., Hill, M.C., and McDonald, M.G., 2000. MODFLOW-2000, The U.S. Geological Survey Modular Ground-Water Model - User guide to modularization concepts and the ground-water flow process: U.S. Geological Survey Open-File Report 00-92, 121 p. 4 Environmental Simulations Inc., 2011. Groundwater Vistas Vers. 6.
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Calibration to measured conditions and completion of a sensitivity analysis
Model verification to evaluate the calibration against a second measured condition
Use of the model as predictive tool
The following sections describe each of these steps for constructing the site numerical groundwater model.
2.2.1 Geometry
The model grid is rotated 69.5° clockwise from due north to parallel the overall landslide movement
direction. The southwest corner of the model grid (model coordinates 0,0) corresponds with state plane
grid coordinates N887,300.26 and E1,721801.06. The model area is 1,600 feet (ft) by 1,600 ft. The model
area was designed to allow simulation of local recharge areas on the hill slope to the southwest, Route 191,
the landslide area, the abandoned power canal, and the Clyde River. The model contains cells in 160 rows
by 160 columns. Horizontal cell dimensions are 10 ft by 10 ft within the entire model domain. There are a
total of 204,800 cells.
Conditions beneath the landslide and the surrounding area are represented by eight model layers. The
model layers generally correspond to the following hydrostratigraphic units, which are directly correlative
with the soil layers described in Section 6.2 of the main report text:
Layer 1: Embankment Fill
Layer 2: Upper Silts and Sands
Layer 3: Upper Silts and Clays
Layer 4: Middle Silts and Sands
Layer 5 Middle Sands and Gravels
Layer 6 Lower Clay
Layer 7 Lower Sands and Gravels
Layer 8 Lower Silts and Weathered Bedrock
Site topographic maps were used to construct Layer 1 top elevations. In some areas of the models, the
upper units are not present (e.g., between the stability berm and Clyde River). In these areas, the layer
thicknesses were set to 0 ft.
2.2.2 Boundary Conditions
Boundary conditions in groundwater models consist of physical and hydraulic boundaries within the model
area. Physical boundary conditions are well defined geologic and hydrologic features that influence the
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groundwater flow pattern. Examples include contacts between two geologic units, faults, surface water
bodies, or anthropogenic structures such as a slurry wall5.
Hydraulic boundaries are derived from the groundwater flow net and are therefore “artificial” boundaries set
by the model designer. Examples include known hydraulic heads represented by equipotential lines; (i.e.,
constant heads). It is desirable to use as few hydraulic boundaries (constant head boundaries) as possible
because they are not permanent features and can change over time; however, constant heads are typically
required in groundwater flow models. Their location is subjective as it is based upon the general
characteristics of the flow nets. The main requirement of hydraulic boundaries is placement far enough
from the area of interest to not influence flow patterns created by project activity (e.g., pumping). The most
common use of constant head boundaries is at the outside edge of a model and in areas where there is a
lack of field data beyond the area of immediate interest.
To model regional groundwater conditions, upgradient recharge boundaries were placed at the southwest
edge of the model domain, and extrapolated using field measurements. These groundwater recharge areas
were modeled using 349 general head boundary cellswithin the coarse-grained hydrostratigraphic units,
i.e., Layers 2, 4 and 7. The hydraulic head within these cells is specified in advance and does not change
during a simulation period5. Potentiometric data are not available for these off-site areas; therefore constant
head values in these areas were estimated from extrapolating groundwater elevations from the nearest
piezometers. These values ranged from 830 ft in Layer 2 to 768 ft in Layer 7, mimicking the downward
vertical gradients measured within the upgradient area of the model domain.
The downgradient boundary conditions are simulated at the downgradient edge of the model domain. The
Clyde River was modeled using river cells, which simulate the flow between an aquifer and a surface water
body such as a river or lake. For each cell, the hydraulic conductance must be specified, which is computed
from the hydraulic conductivity of the riverbed material, the length of the river in the cell, the width of the
river in the cell, and the thickness of the riverbed material5. A total of 420 river cells were used in the model,
placed within Layers 1 through 5 (Layers 1 through 4 do not exist in the vicinity of the river). As the power
canal was likely constructed with a clay liner (most likely derived from excavation and placement of the
Upper Silts and Clays), and is likely isolated from the hydrogeologic system, no river cells or other boundary
conditions were specified in Layer 1 containing the power canal.
2.2.3 Input Parameters
Input parameters required for the numerical model include:
Hydraulic conductivity;
5 Kresic, N., 1997. Quantitative Solutions in Hydrogeology and Groundwater Modeling. CRC press LLC, Boca Raton/New York, 461 p.
Appendix C – Groundwater Modeling 5 Project No.: 1668897
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Precipitation and evapotranspiration; and River hydraulic conductivity, thickness, width and surface water elevation.
The following describes the final calibrated input data set used for the model. Calibration methods and
procedures are described below.
2.2.4 Calibration
Hydraulic Conductivity – In numerical groundwater modeling, hydraulic conductivity is often the most
critical and sensitive modeling parameter5. Hydraulic conductivity values for the model were initially based
on the arithmetic averages of the single-well slug tests completed within the three most-conductive
hydrostratigraphic units (Layers 2, 4 and 7), as well as the results from the pumping tests and geotechnical
laboratory analyses6. The following hydraulic conductivity values were used for each of the four units,
incorporating horizontal anisotropy to mimic observed field conditions and laboratory data:
Embankment Materials Layer 1 (Route 191 and stability berm): Kx,y = 1.3x10-4 and Kz = 1.3x10-5
centimeters per second (cm/sec; 0.37 and 0.037 ft/day, respectively) Upper Silts and Sands in Layer 2: Kx,y = 8.4x10-6 cm/sec and Kz = 1.4x10-6 cm/sec (0.024 and
0.004 ft/day, respectively) Upper Silts and Clays in Layer 3: Kx,y = 3.5x10-7 cm/sec and Kz = 1.4x10-7 cm/sec (0.004 and
0.0004 ft/day, respectively) Middle Silts and Sands in Layer 4: Kx,y = 3.5x10-6 cm/sec and Kz = 3.5x10-7 cm/sec (0.01 and 0.001
ft/day, respectively) Middle Silts and Sands in Layer 5: Kx,y = 1.2x10-4 cm/sec and Kz = 1.2x10-5 cm/sec (0.035 and
0.0035 ft/day, respectively) Lower Clay in Layer 6: Kx,y = 3.5x10-7 cm/sec and Kz = 2.8x10-7 cm/sec (0.001 and 0.0008 ft/day,
respectively) Lower Sands and Gravels in Layer 7: Kx,y = 4.8x10-4 cm/sec and Kz = 6.2x10-5 cm/sec (1.35 and
0.175 ft/day, respectively) Lower Silts and Weathered Bedrock in Layer 8: Kx,y = 1.8x10-4 cm/sec and Kz = 3.5x10-5 cm/sec
(0.5 and 0.1 ft/day, respectively) Precipitation and Evapotranspiration – Precipitation recharge was applied to the top of Layer 1
throughout the model domain, using a value of 7.1x10-9 cm/sec (2.0x10-5 ft/day) as derived from
climatological data recorded in Newport between 2008 and 2012. Recharge rates are difficult to define in
groundwater models, because recharge depends on various factors such as climate, land cover, land use,
topography, etc.5 The model was found to be not very sensitive to precipitation recharge. Due to the general
lack of appreciable vegetative growth, and the lack of impact on the model results, evapotranspiration was
set to 0.
6 Golder Associates Inc., August 2014. Geotechnical Data Report, Route 191 Embankment, Newport, Vermont, VTrans Newport STP 1343(22), Contract PS0172.
Appendix C – Groundwater Modeling 6 Project No.: 1668897
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River Parameters – River boundary cells were used in Layers 1 through 5, although only Layer 5 contains
active river cells. River node width and length were set to the cell dimensions used for the river. A riverbed
depth of one foot was used, and river height varied according to topographic survey information. For each
cell, the hydraulic conductance was calculated, which is computed from the product of hydraulic conductivity
of the riverbed material, the length of the river in the cell, and the width of the river in the cell, divided by
the thickness of the riverbed material. The riverbed conductance (based upon the flux area of the cell and
hydraulic conductivity of the river bed) was 1.9x10-1 cm/sec (5.5x102 ft/day), using a riverbed hydraulic
conductivity of 1.8x10-4 cm/sec (0.5 ft/day).
2.3 Results
2.3.1 Simulated Heads Calibrated to August 2013 Conditions
Numerical model calibration was conducted by comparing simulated hydraulic head values to measured
water levels at the corresponding well and piezometer locations. The model was calibrated to groundwater
elevation data collected August 14, 2013, just prior to implementation of the 24-hour pumping test. The
trial-and-error calibration technique was used to calibrate the model, where model input parameters are
adjusted over a given range until the model satisfactorily matches measured field conditions. Only one
parameter was changed per simulation. Records describing the changed parameter and results were kept
during the calibration effort. As hydraulic conductivity is the most sensitive parameter in modeling (see
above), adjustments to layer hydraulic conductivity (both horizontally and vertically) were the main method
of model calibration.
A statistical evaluation was completed to evaluate the model calibration. At each well location, the residual
(the difference between the measured and simulated groundwater elevations) was calculated. Positive
residual values indicate simulated head values higher than measured elevations. Negative residual values
indicate simulated head elevations lower than measured elevations. The residual mean is the arithmetic
mean of all calculated residual values. Absolute residual mean is the arithmetic mean of the absolute value
of the residuals (all negative residuals considered positive). It is possible that large positive and negative
residuals can cancel one another when calculating arithmetic mean. Therefore, evaluation of the absolute
residual mean as well as the arithmetic mean should be completed to evaluate model calibration. Other
statistics such as the residual standard deviation (the square root of the variance [the average of the
squared deviations from the mean]), and the residual sum of squares (the sum of the squared deviations
around the mean of a random sample divided by the sample size minus one) can also be useful in
evaluation of the calibration process.
Approximately 50 calibration simulations were completed. The results indicate a residual mean of -1.83 ft,
which represents 1.70 percent of the total hydraulic head difference for the model area (approximately 108
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ft). The absolute residual mean for the model run is 7.03 ft, which is 6.51 percent of the total hydraulic head
difference for the entire modeling area. The residual mean and the absolute residual mean are within 10
percent of the total hydraulic head difference for the modeling area, indicating the model may be considered
sufficiently calibrated. (Note that no generally accepted reasoning that supports an assertion that a
calibrated model meets such criteria exists; nor are there established industry guidelines regarding the
acceptable magnitude of the residual mean and absolute residual mean, other than to minimize these
values.7) Given the complexity of the Newport site hydrogeologic conditions, Golder considers the model
calibration results to be considered acceptable, and the model can be used for predictive purposes.
2.3.2 Water Balance
An effective measure of model calibration is the analysis of the water budget calculated by MODFLOW.
The model provides flows across boundaries, flows to and from all sources and sinks, and flows generated
by storage5.
The model inflows consist of general head boundary cells, precipitation recharge, and river cells (at the
river upgradient end). Total model inflows are approximately 1,181.84 cubic feet per day (ft3/day). These
consist of: general head boundary cells (Layers 2, 4 and 7) of approximately 1,170 ft3/day (99% of total
inflow); precipitation recharge (applied to Layer 1 only) of approximately 11.7 ft3/day (0.99% of total inflow);
and total river node inflow of approximately 0.16 ft3/day (0.01% of total inflow). The model outflows consist
of river cells and the artesian piezometers located near the river, and totals approximately 1,182.07 ft3/day.
These consist of: total river node outflow of approximately 970 ft3/day (82.1% of total outflow); and artesian
piezometer outflow of approximately 212 ft3/day (17.9% of total outflow).
The outflow deficit is +0.23 ft3/day, which is equivalent to error between outflow and inflow estimates of
approximately 0.0195%. This indicates that nearly all the water in the model has been accounted for
between the water sources and discharge areas.
2.3.3 Pumping Test Simulation
Once the steady state groundwater model was calibrated to static August 2013 conditions, the model was
converted to a transient one to simulate the 24-hour constant rate pumping test on August 12-13, 2013.
The model grid was further discretized to reduce the cell size to match that of the test well (PTWa) casing
and sand pack diameters. The model was then rerun using the pumping test groundwater pumping rate
(about 6 gallons per minute [gpm]) for 24 hours. The simulated drawdown curves in the pumping well and
nearby piezometers were then compared with the observed drawdown curves from the test. The simulated
data closely matched that observed in the field, and only minor adjustments to the model were performed,
7 Anderson, M.P., Woessner, W.W. and Hunt, R.J., 2015. Applied Groundwater Modeling, 2nd ed., Elsevier, 564 p.
Appendix C – Groundwater Modeling 8 Project No.: 1668897
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including reducing precipitation recharge to nil on the roadway, and slight adjustments to the general head
boundary cells in Layer 2 and in the artesian piezometer outflows.
2.4 Extraction System Scenarios Following compilation of a reasonably calibrated transient groundwater extraction model, Golder simulated
four extraction scenarios to provide estimates of the reduction in pore water pressure to evaluate the
potential increase in the factor-of-safety (FOS), estimate the potential magnitude of each scenario to reduce
landslide movement, and provide design guidance for the selected system. Using ArcGIS, Golder extracted
the porewater pressures (i.e., heads) from the groundwater model cells parallel to the geotechnical cross
sections, and imported them into geotechnical stability modeling software to evaluate the reduction in the
FOS. The groundwater extraction scenarios consisted of:
Scenario A: 12 passive extraction wells placed between the abandoned power canal berm and the Clyde River, tapping Layer 7 artesian conditions, each with about 1 gpm flow;
Scenario B: Three pumping wells placed between the abandoned power canal berm and the Clyde River, tapping Layer 7, each with about 6 gpm flow;
Scenario C: Three pumping wells placed on the abandoned power canal berm, tapping Layer 7; each with about 6 gpm flow and
Scenario D: Three pumping wells placed on the stability berm, tapping Layer 7, each with about 6 gpm flow.
All four scenarios indicated the FOS could be increased with reduction of pore water pressure via
groundwater extraction. The increases ranged from the baseline FOS condition parallel to landslide
movement (i.e., cross section A-A’) of 1.001 to 1.194 for Scenario A (19% increase); 1.332 for Scenario B
(33% increase); 1.365 for Scenario C (35% increase), and 1.272 for Scenario D (27% increase).
2.4.1 Selected Extraction System
VTrans then considered each scenario with regards to right-of-way access for the potential extraction
systems located northeast of the stability berm (on property not controlled by VTrans), possible groundwater
discharge points, environmental permitting, wetlands impacts, power supply, and operations and
maintenance. Ultimately VTrans decided to develop Scenario D for final groundwater extraction system
design and implementation.
2.5 Evaluation of Selected Extraction System on Nearby Water Supply Wells Review of the regional topography from USGS maps and of Vermont Agency of Natural Resources
(VTANR) Geographic Information System8 well records indicates seven (7) private residence groundwater
8 Vermont Agency of Natural Resources Natural Resources Atlas: http://anr.vermont.gov/maps/nr-atlas; accessed June 13, 2017.
Appendix C – Groundwater Modeling 9 Project No.: 1668897
p:\projects\2016\1668897 vtrans newport supplemental design\700 reports\draft report\appendices\appendix c - groundwater modeling\appendix c - newport groundwater modeling.docx
extraction wells and one (1) public facility groundwater extraction well (at a golf course) exist upgradient or
side-gradient of the landslide site. These wells are approximately 900 to 2,660 ft northwest, west and
southwest of the stability berm area (i.e., pumping test well PTWa). (It should be noted that the well location
accuracy within the VTANR database can be off by several 100’s of ft.) The VTANR driller’s records indicate
all these wells are open within the bedrock interval, i.e., the overburden intervals are cased. The wells
range in depth from 100 to 650 ft. While overburden sand and gravel deposits can yield greater
groundwater flows, often the bedrock produces better quality groundwater and groundwater wells are
commonly completed with an open interval within the bedrock, tapping fractures for sources of groundwater.
Reported static groundwater depths range from 20 to 60 ft below ground surface (bgs), and yields from
these wells range from 2 to 15 gpm. Using estimated ground surface elevations, these correspond to static
groundwater elevations ranging from 905 to 968 ft mean sea level (msl).
Comparison of these well data with the conceptual site hydrogeologic model indicates that these wells are
considered upgradient in two ways: 1) The static groundwater levels are significantly higher than those
measured in the piezometers located above the scarp of the landslide (by about 90 ft); and 2) They are
screened in bedrock, which receives its recharge from the overburden sediments lying directly above it. In
the conceptual model, and as simulated in the numerical groundwater model, the groundwater within the
upgradient bedrock and overburden provides the source of groundwater for the landslide area, which lies
downgradient or side-gradient of the eight (8) wells. As such, extraction of groundwater from Layer 7 for
the extraction system (at a total estimated rate of 18 gpm) is not expected to impact these wells.
To further evaluate the potential for impacts to the eight wells, Golder then modified the steady-state
numerical groundwater model to simulate conditions upgradient (southwest) of the landslide area, by
extending the eight hydrostratigraphic layers, using the golf course well driller’s log to estimate bedrock
depth. It should be noted that there are little accurate and detailed surface and subsurface data in this
area; however, the key extraction target layer (Layer 7) and the bedrock surface were extended to the
southwest in a simplified manner, using the golf course well data and reported static groundwater elevation
(905 ft msl). The model then was run with the Scenario D extraction wells under non-pumping and pumping
conditions to estimate the potential effect of groundwater extraction on the golf course well. The results
indicate Scenario D steady-state pumping likely will not reduce the reported static groundwater elevation in
the golf course well. It should be noted that this revised model is not calibrated outside of the landslide
area, does not simulate long-term transient groundwater extraction under Scenario D, and does not account
for the actual pumping rates and drawdown from the eight private/public extraction wells. It should also be
noted that the VTANR well database may not be complete. Additional model development would be needed
to provide more accurate assessment of the potential for upgradient well impacts from groundwater
extraction from the landslide site.
APPENDIX D TOTAL DYNAMIC HEAD WORKSHEETS
TDH Worksheets.xlsx
Hazen-Williams Friction Loss Equation
F = 0.2083(100/C)^1.852*Q^1.852/dh^4.8655where Bhp = Breaking horse powerF = friction head loss in feet of water per foot of pipe Q = Maximum pumping rate in gpmC = Hazen-Williams roughness constant (140) TDH = Total dynamic head in feetQ = flow rate (gpm) PE = Pump efficiency in percent (assume 75%)dh = inside hydrualic diameter (inches) ME = Motor efficiency in percent (assume 90%)
Well AW-1WellheadGround Elevation = 782 ft mslDischarge Elevation = 805 ft mslPump Intake Depth = 111 ft bgs Max Pumping Level (MPWL)Est. Pumping Level = 82 ft bgsPumping Rate (Q) 10 gpmPipe TypePump Column Diameter (dh) = 1.92 inches 2 OD, 1.92 IDFriction Loss (F) = 0.003 per footWell Friction Loss = 0.4 feetTDH at the Wellhead = 111.4 feet MPWL + FDistribution SystemCombined Pumping Rate 30 gpm Combined flow from 3 wells at 10 gpm eachMax. Elevation Change: 23 feet Discharge Elev. - Wellhead ElevPipe Length = 418 feetPipe TypePipe Diameter = 2.83 inches; 3 OD, 2.83 IDFriction Loss = 0.004 per footFriction Loss in Pipeline = 1.6 feetFriction Loss in Components = 0.1 feet
Fitting/System Component Qty90 Elbows (molded) 2 7.5 feet45 Elbows (molded) 2 7.5 feetTee, Run 3 14.2 feetTee, Branch 0 0.0 feetGate Valve(full open) 0 0.0 feetButterfly Val. (full open) 0 0.0 feetCheck Valve (Swing) 0 0.0 feetFlow Meter (Mag) 0 0.0 feetEquiv. Length Total 29.2 feet
Required Distribution Pressure = 0 psi; = 0 feetTDH from Distribution System = 24.7 feet (Elev. Change+ Fiction Loss+Distribution Press.)TDH = 136 feet (Rounded to nearest ft.)Pumping Rate: 10 gpmInput Horsepower: 0.5 hp
Prepared by: BWChecked by: JRS
Reviewed by: KGK
SUBMERSIBLE PUMP DESIGN SHEET
Polyethylene, PE, PEH
Polyethylene, PE, PEH
MEPETDHQBhp
**960,3
*=
TDH Worksheets.xlsx
Hazen-Williams Friction Loss Equation
F = 0.2083(100/C)^1.852*Q^1.852/dh^4.8655where Bhp = Breaking horse powerF = friction head loss in feet of water per foot of pipe Q = Maximum pumping rate in gpmC = Hazen-Williams roughness constant (140) TDH = Total dynamic head in feetQ = flow rate (gpm) PE = Pump efficiency in percent (assume 75%)dh = inside hydrualic diameter (inches) ME = Motor efficiency in percent (assume 90%)
Well AW-2WellheadGround Elevation = 793 ft mslDischarge Elevation = 805 ft mslPump Intake Depth = 119 ft bgs Max Pumping Level (MPWL)Est. Pumping Level = 93 ft bgsPumping Rate (Q) 10 gpmPipe TypePump Column Diameter (dh) = 1.92 inches 2 OD, 1.92 IDFriction Loss (F) = 0.003 per footWell Friction Loss = 0.4 feetTDH at the Wellhead = 119.4 feet MPWL + FDistribution SystemCombined Pumping Rate 30 gpm Combined flow from 3 wells at 10 gpm eachMax. Elevation Change: 12 feet Discharge Elev. - Wellhead ElevPipe Length = 255 feetPipe TypePipe Diameter = 2.83 inches; 3 OD, 2.83 IDFriction Loss = 0.004 per footFriction Loss in Pipeline = 1.0 feetFriction Loss in Components = 0.1 feet
Fitting/System Component Qty90 Elbows (molded) 2 7.5 feet45 Elbows (molded) 2 7.5 feetTee, Run 1 4.7 feetTee, Branch 1 14.2 feetGate Valve(full open) 0 0.0 feetButterfly Val. (full open) 0 0.0 feetCheck Valve (Swing) 0 0.0 feetFlow Meter (Mag) 0 0.0 feetEquiv. Length Total 34.0 feet
Required Distribution Pressure = 0 psi; = 0 feetTDH from Distribution System = 13.1 feet (Elev. Change+ Fiction Loss+Distribution Press.)TDH = 133 feet (Rounded to nearest ft.)Pumping Rate: 10 gpmInput Horsepower: 0.5 hp
Prepared by: BWChecked by: JRS
Reviewed by: KGK
SUBMERSIBLE PUMP DESIGN SHEET
Polyethylene, PE, PEH
Polyethylene, PE, PEH
MEPETDHQBhp
**960,3
*=
TDH Worksheets.xlsx
Hazen-Williams Friction Loss Equation
F = 0.2083(100/C)^1.852*Q^1.852/dh^4.8655where Bhp = Breaking horse powerF = friction head loss in feet of water per foot of pipe Q = Maximum pumping rate in gpmC = Hazen-Williams roughness constant (140) TDH = Total dynamic head in feetQ = flow rate (gpm) PE = Pump efficiency in percent (assume 75%)dh = inside hydrualic diameter (inches) ME = Motor efficiency in percent (assume 90%)
Well AW-3WellheadGround Elevation = 802 ft mslDischarge Elevation = 805 ft mslPump Intake Depth = 145 ft bgs Max Pumping Level (MPWL)Est. Pumping Level = 102 ft bgsPumping Rate (Q) 10 gpmPipe TypePump Column Diameter (dh) = 1.92 inches 2 OD, 1.92 IDFriction Loss (F) = 0.003 per footWell Friction Loss = 0.5 feetTDH at the Wellhead = 145.5 feet MPWL + FDistribution SystemCombined Pumping Rate 30 gpm Combined flow from 3 wells at 10 gpm eachMax. Elevation Change: 3 feet Discharge Elev. - Wellhead ElevPipe Length = 94 feetPipe TypePipe Diameter = 2.83 inches; 3 OD, 2.83 IDFriction Loss = 0.004 per footFriction Loss in Pipeline = 0.4 feetFriction Loss in Components = 0.1 feet
Fitting/System Component Qty90 Elbows (molded) 2 7.5 feet45 Elbows (molded) 2 7.5 feetTee, Run 0 0.0 feetTee, Branch 1 14.2 feetGate Valve(full open) 0 0.0 feetButterfly Val. (full open) 0 0.0 feetCheck Valve (Swing) 0 0.0 feetFlow Meter (Mag) 0 0.0 feetEquiv. Length Total 29.2 feet
Required Distribution Pressure = 0 psi; = 0 feetTDH from Distribution System = 3.5 feet (Elev. Change+ Fiction Loss+Distribution Press.)TDH = 149 feet (Rounded to nearest ft.)Pumping Rate: 10 gpmInput Horsepower: 0.6 hp
Prepared by: BWChecked by: JRS
Reviewed by: KGK
SUBMERSIBLE PUMP DESIGN SHEET
Polyethylene, PE, PEH
Polyethylene, PE, PEH
MEPETDHQBhp
**960,3
*=
TDH Worksheets.xlsx
Hazen-Williams Friction Loss Equation
F = 0.2083(100/C)^1.852*Q^1.852/dh^4.8655where Bhp = Breaking horse powerF = friction head loss in feet of water per foot of pipe Q = Maximum pumping rate in gpmC = Hazen-Williams roughness constant (140) TDH = Total dynamic head in feetQ = flow rate (gpm) PE = Pump efficiency in percent (assume 75%)dh = inside hydrualic diameter (inches) ME = Motor efficiency in percent (assume 90%)
Well PTWaWellheadGround Elevation = 792 ft mslDischarge Elevation = 805 ft mslPump Intake Depth = 125 ft bgs Max Pumping Level (MPWL)Est. Pumping Level = 100 ft bgsPumping Rate (Q) 10 gpmPipe TypePump Column Diameter (dh) = 1.92 inches 2 OD, 1.92 IDFriction Loss (F) = 0.003 per footWell Friction Loss = 0.4 feetTDH at the Wellhead = 125.4 feet MPWL + FDistribution SystemCombined Pumping Rate 30 gpm Combined flow from 3 wells at 10 gpm eachMax. Elevation Change: 13 feet Discharge Elev. - Wellhead ElevPipe Length = 328 feetPipe TypePipe Diameter = 2.83 inches; 3 OD, 2.83 IDFriction Loss = 0.004 per footFriction Loss in Pipeline = 1.3 feetFriction Loss in Components = 0.3 feet
Fitting/System Component Qty90 Elbows (molded) 2 7.5 feet45 Elbows (molded) 2 7.5 feetTee, Run 2 9.4 feetTee, Branch 1 14.2 feetGate Valve(full open) 1 1.9 feetButterfly Val. (full open) 0 0.0 feetCheck Valve (Swing) 1 23.6 feetFlow Meter (Mag) 1 2.4 feetEquiv. Length Total 66.5 feet
Required Distribution Pressure = 0 psi; = 0 feetTDH from Distribution System = 14.5 feet (Elev. Change+ Fiction Loss+Distribution Press.)TDH = 140 feet (Rounded to nearest ft.)Pumping Rate: 10 gpmInput Horsepower: 0.5 hp
Prepared by: BWChecked by: JRS
Reviewed by: KGK
SUBMERSIBLE PUMP DESIGN SHEET
Polyethylene, PE, PEH
Polyethylene, PE, PEH
MEPETDHQ
Bhp**960,3
*=
TDH Worksheets.xlsx
Hazen-Williams Friction Loss Equation
F = 0.2083(100/C)^1.852*Q^1.852/dh^4.8655where Bhp = Breaking horse powerF = friction head loss in feet of water per foot of pipe Q = Maximum pumping rate in gpmC = Hazen-Williams roughness constant (140) TDH = Total dynamic head in feetQ = flow rate (gpm) PE = Pump efficiency in percent (assume 75%)dh = inside hydrualic diameter (inches) ME = Motor efficiency in percent (assume 90%)
Well AW-3 (50% Blockage)WellheadGround Elevation = 802 ft mslDischarge Elevation = 805 ft mslPump Intake Depth = 145 ft bgs Max Pumping Level (MPWL)Est. Pumping Level = 100 ft bgsPumping Rate (Q) 10 gpmPipe TypePump Column Diameter (dh) = 0.96 inches 2 OD, 1.92 IDFriction Loss (F) = 0.097 per footWell Friction Loss = 14.1 feetTDH at the Wellhead = 159.1 feet MPWL + FDistribution SystemCombined Pumping Rate 30 gpm Combined flow from 3 wells at 10 gpm eachMax. Elevation Change: 3 feet Discharge Elev. - Wellhead ElevPipe Length = 94 feetPipe TypePipe Diameter = 1.415 inches; 3 OD, 2.83 IDFriction Loss = 0.112 per footFriction Loss in Pipeline = 10.6 feetFriction Loss in Components = 1.6 feet
Fitting/System Component Qty90 Elbows (molded) 2 3.8 feet45 Elbows (molded) 2 3.8 feetTee, Run 0 0.0 feetTee, Branch 1 7.1 feetGate Valve(full open) 0 0.0 feetButterfly Val. (full open) 0 0.0 feetCheck Valve (Swing) 0 0.0 feetFlow Meter (Mag) 0 0.0 feetEquiv. Length Total 14.6 feet
Required Distribution Pressure = 0 psi; = 0 feetTDH from Distribution System = 15.2 feet (Elev. Change+ Fiction Loss+Distribution Press.)TDH = 174 feet (Rounded to nearest ft.)Pumping Rate: 10 gpmInput Horsepower: 0.7 hp
Prepared by: BWChecked by: JRS
Reviewed by: KGK
SUBMERSIBLE PUMP DESIGN SHEET
Polyethylene, PE, PEH
Polyethylene, PE, PEH
MEPETDHQ
Bhp**960,3
*=
APPENDIX G ACCESS ROAD GLOBAL STABILITY RESULTS
1.211.21W
W
250.00 lbs/ft2
1.211.21
Material Name Color Unit Weight(lbs/ 3) Strength Type Cohesion
(psf)Phi(deg)
Embankment Fill 125 Mohr‐Coulomb 0 35
Asphalt 120 Mohr‐Coulomb 0.02 35
Vegeta on 120 Mohr‐Coulomb 50 30
Upper Silts & Sands 120 Mohr‐Coulomb 0 35
Stability Berm 130 Mohr‐Coulomb 0 35
Rip Rap 140 Mohr‐Coulomb 0 45
Reworked Silts and Clays 125 Mohr‐Coulomb 0 32
Upper Silts & Clays 120 Undrained 3500
Middle Silts & Sands 120 Mohr‐Coulomb 0 38
900
875
850
825
800
775
-120 -100 -80 -60 -40 -20 0 20 40 60 80 100 120
Analysis Description Station 53 + 00: Existing Access Road Conditions
Figure G-1Scale 1:300Reviewed by:Checked by:Drawn By JDL
Date 6/29/2017
Project
Newport Rt. 191 Landlside
SLIDEINTERPRET 7.024
LLM CCB
1.401.40
W
W
250.00 lbs/ft2
1.401.40Material Name Color Unit Weight
(lbs/ 3) Strength Type Cohesion(psf)
Phi(deg)
Embankment Fill 125 Mohr‐Coulomb 0 35
Asphalt 120 Mohr‐Coulomb 0.02 35
Structural Fill 125 Mohr‐Coulomb 0 35
Vegeta on 120 Mohr‐Coulomb 50 30
Upper Silts & Sands 120 Mohr‐Coulomb 0 35
Stability Berm 130 Mohr‐Coulomb 0 35
Rip Rap 140 Mohr‐Coulomb 0 45
Reworked Silts and Clays 125 Mohr‐Coulomb 0 32
Upper Silts & Clays 120 Undrained 3500
Middle Silts & Sands 120 Mohr‐Coulomb 0 38
900
875
850
825
800
775
-120 -100 -80 -60 -40 -20 0 20 40 60 80 100 120
Analysis Description Station 53 + 00: Proposed Access Road Conditions
Figure G-2Scale 1:300Reviewed by:Checked by:Drawn By JDL
Date 6/29/2017
Project
Newport Rt. 191 Landlside
SLIDEINTERPRET 7.024
LLM CCB
1.47
1.54
W
W
250.00 lbs/ft2
1.47
1.54
925
900
875
850
825
800
775
-125 -100 -75 -50 -25 0 25 50 75 100 125 150
Analysis Description Station 54 + 00: Existing Access Road Conditions
Figure G-3Scale 1:350Reviewed by:Checked by:Drawn By JDL
Date 7/13/2017
Project
Newport Rt. 191 Landlside
SLIDEINTERPRET 7.024
1.471.47
Material Name Color Unit Weight(lbs/ 3) Strength Type Cohesion
(psf)Phi(deg)
125 Mohr‐Coulomb 0 35
120 Mohr‐Coulomb 0.02 35
125 Mohr‐Coulomb 0 35
120 Mohr‐Coulomb 50 30
120 Mohr‐Coulomb 0 35
130 Mohr‐Coulomb 0 35
140 Mohr‐Coulomb 0 45
125 Mohr‐Coulomb 0 32
120 Undrained 3500
Embankment Fill
Asphalt
Structural Fill
Vegeta on
Upper Silts & Sands
Stability Berm
Rip Rap
Reworked Silts and Clays
Upper Silts & Clays
Middle Silts & Sands 120 Mohr‐Coulomb 0 38
LLM CCB
1.54
1.54
1.43
1.36W
W
250.00 lbs/ft2
1.54
1.54
1.43
1.36
925
900
875
850
825
800
775
-125 -100 -75 -50 -25 0 25 50 75 100 125 150
Analysis Description Station 54 + 00: Less Fill
Figure G-4Scale 1:350Reviewed by:Checked by:Drawn By JDL
Date 7/13/2017
Project
Newport Rt. 191 Landlside
SLIDEINTERPRET 7.024
Material Name Color Unit Weight(lbs/ 3) Strength Type Cohesion
(psf)Phi(deg)
125 Mohr‐Coulomb 0 35
120 Mohr‐Coulomb 0.02 35
125 Mohr‐Coulomb 0 35
120 Mohr‐Coulomb 50 30
120 Mohr‐Coulomb 0 35
130 Mohr‐Coulomb 0 35
140 Mohr‐Coulomb 0 45
125 Mohr‐Coulomb 0 32
120 Undrained 3500
Embankment Fill
Asphalt
Structural Fill
Vegeta on
Upper Silts & Sands
Stability Berm
Rip Rap
Reworked Silts and Clays
Upper Silts & Clays
Middle Silts & Sands 120 Mohr‐Coulomb 0 38
LLM CCB
Golder, Golder Associates and the GA globe design are trademarks of Golder Associates Corporation
Golder Associates Inc. 670 N. Commercial Street, Suite 103
Manchester, NH 03101 USA Tel: (603) 668-0880 Fax: (603) 668-1199