asbestos remediation plan for forested areas near libby, montana

Asbestos Remediation Plan for

Forested Areas near Libby, Montana

Developed for:

Lincoln County Port Authority

Libby, Montana

Final Report September 2012

Asbestos Remediation Plan for

Forested Areas near Libby, MT

Developed for:

Lincoln County Port Authority

Libby, Montana

Project Team:

Roy Anderson, Senior Consultant,

The Beck Group, Portland, Oregon

Greg Frame, Estimating Manager

Envirocon, Inc., Missoula, Montana

Craig Rawlings, Principal

Forest Business Network, Missoula, Montana

Project Reviewers:

Tony Ward, Assistant Professor

University of Montana, Missoula, Montana

Bob Rummer, Project Leader Forest Operations Research

U.S. Forest Service, Auburn, Alabama

Final Report

September 2012

Table of Contents

Page

CHAPTER 1 – EXECUTIVE SUMMARY ............................................................................... 1

1.1 Introduction .............................................................................................................. 1

1.2 The Operating Environment .................................................................................... 2

1.2.1 Landowners ........................................................................................................................ 2

1.2.2 Tree Biomass in OU3 ......................................................................................................... 3

1.2.3 Road System ...................................................................................................................... 4

1.2.4 Asbestos Levels ................................................................................................................. 4

1.3 The Remediation Plans ............................................................................................ 5

1.3.1 Standing Tree Remediation Plan ....................................................................................... 5

1.3.2 Forest Floor Duff Remediation Plan ................................................................................... 8

1.4 Recommendations ................................................................................................... 8

CHAPTER 2 – THE OPERATING ENVIRONMENT............................................................. 11

2.1.1 Existing Tree Vegetation .................................................................................................. 11

2.1.2 Road Density .................................................................................................................... 13

2.1.3 Topography ...................................................................................................................... 14

2.1.4 Asbestos Levels ............................................................................................................... 14

CHAPTER 3 – REMEDIATION PLANNING APPROACH ................................................... 19

CHAPTER 4 – STANDING TREE REMEDIATION PLAN.................................................... 20

4.1 Standing Tree Remediation Plan Objectives ........................................................ 20

4.2 Timber Harvesting Technology ............................................................................. 20

4.2.1 General Discussion of the Technologies Selected .......................................................... 21

Timber Felling ......................................................................................................... 22 4.2.1.1

Extraction ................................................................................................................ 25 4.2.1.2

Merchandising – Delimbing .................................................................................... 27 4.2.1.3

Truck Loading ......................................................................................................... 28 4.2.1.4

Hauling ................................................................................................................... 29 4.2.1.5

4.2.2 Equipment & Operating Modifications Needed for OU3 Plan Implementation ................ 30

General Approach .................................................................................................. 30 4.2.2.1

Equipment Modifications ........................................................................................ 32 4.2.2.2

Operator Modifications ........................................................................................... 32 4.2.2.3

Monitoring ............................................................................................................... 32 4.2.2.4

Table of Contents

CHAPTER 5 – FOREST DUFF REMEDIATION PLAN ........................................................ 33

5.1 Forest Duff Remediation Technology ................................................................... 33

5.1.1 Remediation of Northern Europe Forests ........................................................................ 33

5.1.2 Combination Industrial Vacuum System and Portable Conveyor .................................... 34

5.1.3 Beneficial Land Cover ...................................................................................................... 35

CHAPTER 6 – MATERIAL UTILIZATION ........................................................................... 36

6.1 General Utilization Concepts ................................................................................. 36

6.1.1 Establish a Permanent Utilization Structure .................................................................... 36

6.1.2 Site Control ...................................................................................................................... 37

6.2 Specific Products That Might Be Produced ......................................................... 37

6.2.1 Sawlogs ............................................................................................................................ 38

6.2.2 Pulp Chips ........................................................................................................................ 38

6.2.3 Hog Fuel ........................................................................................................................... 39

6.2.4 Logging Slash .................................................................................................................. 39

6.2.5 Firewood .......................................................................................................................... 40

6.3 Budgetary Capital Cost Estimates ........................................................................ 40

6.4 Estimated Required Staffing Levels ...................................................................... 41

THE BECK GROUP Page 1 Portland, OR

CHAPTER 1 – EXECUTIVE SUMMARY

1.1 INTRODUCTION

The forest surrounding the former W.R. Grace vermiculite mine near Libby, Montana

has been found to be contaminated with asbestos fibers. Since exposure to those

asbestos fibers can reasonably be expected to be a health risk for humans and since

wide spread exposure to humans could occur during a wildfire event, the Lincoln County

Port Authority (LCPA), in consultation with the U.S. Forest Service (USFS) and the

Montana Department of Natural Resources and Conservation (DNRC), seek a timber

harvesting technical plan for removing asbestos contaminated standing trees and forest

floor duff from the forests in an area identified by the United States Environmental

Protection Agency (USEPA) as Operable Unit 3 (OU3 – see Figure 1). Timber

harvesting was selected as the focus of the study because of the high per acre fuel

volumes in OU3, the well-developed state of timber harvesting technology, and the

desire to identify a practical approach that also offers the opportunity to offset

remediation costs with saleable products produced by the effort.

FIGURE 1 – AERIAL PHOTO OF CURRENT OU3 AREA

To develop the technical plan, LCPA retained the services of a consulting team that

included The Beck Group; Forest Business Network; and Envirocon, Inc. (the project

team). The combined expertise of the project team includes timber harvesting,

wood/biomass utilization, and environmental remediation. The objective of the team’s

work was to develop a preliminary technical plan for remediating the forest in OU3.

Chapter 1 – Executive Summary


The OU3 area is part of the Libby Asbestos Superfund site that was established in

2002. It surrounds the former W.R. Grace vermiculite mine near Libby, Montana, and it

is approximately 35,000 acres in size. According to the USEPA, expansion of the OU3

perimeter is under consideration as further testing has shown asbestos contaminated

trees outside the current OU3 boundary. At this point, the extent of the potential

expansion is not known.

Implementation of the technical plan developed as part of this project is expected to

reduce the amount of biomass in OU3, which in turn would reduce the danger of wildfire

in OU3, which in turn would mitigate the risk of the asbestos currently contained in the

trees and forest floor duff from becoming airborne and spreading and contaminating a

much broader area during a wildfire event. Implementation of the plan is also expected

to allow the public to maintain some amount of access to OU3.

The following sections of the executive summary provide a description of the project

team’s plan, as well as a summary of the project team’s recommendations and

conclusions. The team appreciates the opportunity to assist on this important project.

1.2 THE OPERATING ENVIRONMENT

1.2.1 Landowners

At the current time OU3 is about 35,000 acres. The major landowners in OU3 include

the U.S. Forest Service, State of Montana, Plum Creek Timber Company, and Kootenai

Development Company (W.R. Grace). Table 1 shows the estimated acreage owned by

each.

TABLE 1 – ESTIMATED DISTRIBUTION OF

LANDOWNERSHIP IN LIBBY OU3 AREA

Landowner Estimated Acres

Owned

United States Forest Service 23,973

Plum Creek Timber Company 5,433

Kootenai Development Company (W.R. Grace) 3,629

Other Miscellaneous Private Owners 1,325

State of Montana 640

Total 35,000



1.2.2 Tree Biomass in OU3

No inventory of the trees in OU3 was completed as part of this study. However, based

on the US Forest Service’s FIA timber inventory database, for the area covered within a

20 mile radius of the mine site, there is estimated to be an average 611 trees per acre.

When this per acre average for the region is applied to the 35,000 acres of OU3, the

resulting estimate of total merchantable standing tree volume (for all trees greater than

5 inches in diameter at breast height) in OU3 is 65.4 million cubic feet, or 850,000 bone

dry tons, or about 425 million board feet. This translates to a per acre average volume

of about 1,900 cubic feet, 25 bone dry tons, or 12.4 thousand board feet.

About 270,000 bone dry tons (or about 44 percent) is estimated to be found in pulpwood

size trees (those less than 11 inches in diameter at breast height). About 455,000 bone

dry tons is estimated to be found in trees larger than 11 inches in diameter at breast

height. The balance of about 125,000 bone dry tons is estimated to be the bark of the

trees.

In addition to the “merchantable” volumes described in the preceding paragraph, there

is also biomass volume in the limbs and tops of the trees. During typical logging

operations, the limbs and tops (i.e., logging slash) are either left scattered across a

logging unit, or piled at a landing. For this project, an effort would be made to collect

and utilize all logging slash. The project team estimates that in OU3 there are 425,000

bone dry tons of limbs and tops.

Table 2 summarizes the volume of various materials estimated to be found in OU3.

TABLE 2 – ESTIMATED VOLUME OF BIOMASS IN OU3

Material

Type

Bone Dry

Tons

Sawlogs 455,000

Pulp Chips 270,000

Bark 125,000

Logging Slash 425,000

Total 1,275,000



1.2.3 Road System

The existing road system within OU3 is fairly well distributed, with the exception of the

southern portion of the area, which has relatively few roads. While the project team did

not inspect the existing road system within OU3 first hand, we did, however, view the

area from the perimeter and we viewed and analyzed aerial photos and topographic

maps of the area.

The project team estimates that the road density in OU3 is 1.75 (95 miles of forest road

per 54.7 square miles of land area in OU3). Importantly, for our recommendations

about how the biomass can be utilized, the mine site is centrally located within OU3 and

appears to be accessible from most points in OU3 without the need for log trucks to

travel on Highway 37.

Please note, however, that if OU3 is expanded, it may become necessary for log trucks

loaded with asbestos contaminated logs to travel on major public highways. The project

team has not investigated this possibility in detail, but log trailers have been developed

that have curtain sides1. Thus, it is possible that the logs can safely be transported on

major public roads so long as it is done using the enclosed log trailers. More research

on the feasibility and safety of material transport is needed if the area of OU3 is

expanded.

While the project team did not have an opportunity to tour the interior of OU3, it is

readily apparent from topographic maps of the region that the terrain within OU3 is very

challenging, especially in the western portion of the area. The steepness of the terrain

limits the choices of equipment available for timber harvesting operations, but it does

not prevent timber operations altogether. Specific equipment considerations are

discussed in greater detail in the body of the report.

1.2.4 Asbestos Levels

Asbestos levels on the trees in OU3 have been documented in several studies. For

example, the US EPA completed a study2 in which transects from 3 miles to nearly 10

miles long were run radially from the mine site. Tree bark samples were taken at

regular intervals along each transect. The results indicate that no fibers were detected

along some transects, while on others as many as 50 asbestos fibers were found per

1 See: Log-Chip Trailer Offers Flexibility accessed at http://www.forestnet.com/TWissues/Jan_feb_10/log_chip.php

2 Libby OU3 Phase I Sampling and Analysis Plan. USEPA. Completed 9/7/11.

http://www.forestnet.com/TWissues/Jan_feb_10/log_chip.php



sample. Another study3 completed by a University of Montana team in 2004 found trees

close to the mine site contained between 14 million and 260 million amphibole fibers per

square centimeter of bark surface area. Another study4 was completed by Tetra Tech

EM, Inc. for the Montana Department of Environmental Quality. That study was

completed on the Upper Flower Creek Timber Sale located south of Libby, Montana.

The site is owned by the State of Montana and managed by the Department of Natural

Resources and Conservation. The study found that Libby Amphibole fibers (asbestos)

concentrations ranged from no detection to nearly 283,000 structures per square

centimeter of tree bark. Samples were also taken from forest duff and were found to

range from no detection to 12 million structures per gram of dry weight of duff.

1.3 THE REMEDIATION PLANS

The project team organized its work into two distinct plans. The first is a remediation

plan for treating standing trees, and the second includes recommendations for treating

forest floor duff. Please note that for the standing tree remediation plan, the approach

taken was that identifying the silvicultural treatment (e.g., clearcut, seed-tree harvest,

shelterwood harvest, thinning, etc.) applied during timber harvesting was beyond the

scope of this study. Instead, each landowner within OU3 will have to determine for

themselves the most appropriate silvicultural prescription at the time of harvest.

1.3.1 Standing Tree Remediation Plan

With regard to the standing tree remediation plan for OU3, the project team

recommends at this time that a mechanized, whole-tree harvesting system be used to

carry out timber harvesting operations. More specifically, trees will be felled with a

tracked feller buncher, then brought to a landing with either a grapple skidder or cable

yarding system (depending on the terrain). Each tree will then be delimbed and topped

at the landing with either a stroke-boom delimber or a processor and be loaded onto

conventional log trucks with a tracked loader. The log trucks will transport the logs to

either a landfill, or to a utilization facility.

To control and contain the asbestos fibers on the trees during such timber harvesting

activities, a number of modifications to normal timber harvesting and transport

3 See: Amphibole Asbestos Fibers in Tree Bark – A Review of Findings for this Inhalational Exposure Source in Libby, Montana.

In: Journal of Occupational and Environmental Hygiene.

4 See: Final Data Report for DNRC Tree Bark ahnd Duff Smapling for the Upper Flower Creek Timber Sale, Task Order No. 93,

DEQ Contract 407026. Accessed at: http://www.epa.gov/region8/superfund/libby/OU3_FinalDataReport_TreeBark-

DuffSampling-UpperFlowerCreekTimberSaleAreaFeb-3-2012.pdf

http://www.epa.gov/region8/superfund/libby/OU3_FinalDataReport_TreeBark-DuffSampling-UpperFlowerCreekTimberSaleAreaFeb-3-2012.pdf

http://www.epa.gov/region8/superfund/libby/OU3_FinalDataReport_TreeBark-DuffSampling-UpperFlowerCreekTimberSaleAreaFeb-3-2012.pdf



procedures will be required. The following list provides a brief description of each

modification:

To mitigate the potential for the asbestos on trees to become airborne during

logging operations, it is recommended that timber harvesting activities in OU3 be

restricted to certain times of the year. The optimal time for mitigating asbestos

fiber release during timber harvesting is during the winter months when the

ground and trees are frozen. It is expected that the asbestos fibers during these

conditions will largely remain frozen to the bark and therefore will be less likely to

become airborne.

Since the extent of the remediation effort is very large and since there is concern

about the limited amount of time that freezing weather conditions will exist, the

project team also recommends testing timber harvesting operations during the

“shoulder seasons” of spring and fall. The testing would measure the extent of

asbestos fiber release at the timber harvesting site at times when air

temperatures are cooler, the relative humidity is higher, (i.e., during conditions

which are expected to be less likely to create airborne asbestos as a result of

timber harvesting). The USEPA conducted tests in OU3 during the late summer

of 2012, measuring the impact on air quality of timber harvesting operations. The

results of those tests were not available at the time of this study. However, those

results should be considered in assessing the timing of remediation efforts in

OU3.

To the extent possible, all timber harvesting equipment operators and log truck

drivers will work only from within the enclosed cab of their machines. The cab of

each machine will be equipped with positive air pressure HEPA filter systems.

This type of equipment is readily available.

To eliminate the possibility of recontamination, the sequence of remediation

efforts will be to first harvest trees in an area. After all trees scheduled for

harvest have been removed, the area will be reentered, and the forest floor duff

remediation plan will be completed.

A site safety and health plan (SSHP) will be developed for work that occurs in

contaminated areas. This SSHP will include all requirements for working within

contaminated areas of OU3.

For certain timber harvesting activities (i.e., cable yarding), workers will have to

work outside of an enclosed, air controlled cab environment. These activities will

include workers setting chokers on logs and hooking the logs to the

yarder/carriage. These workers will be working in the harvest unit, while other

workers will be working on the landing unhooking the logs from chokers. All of



these workers will wear personal protective equipment (PPE) during logging

operations, as defined in the SSHP. All procedures, as defined in the SSHP, will

be followed while working in contaminated areas of OU3.

To meet the activity based air quality standards that are expected to be

established as part of the OU3 timber harvesting remediation process,

engineering controls may be needed to be implemented. These controls may

include reduced work speed, application of water to key site areas, or application

of crusting agents to control dust.

A sampling and analysis plan (SAP) will be developed for use during the logging

activities to determine the levels of PPE and engineering controls that will be

required to be implemented to meet air emission standards.

Monitoring may indicate airborne asbestos levels during logging that are higher

than allowed limits. The project team recommends that the USFS, EPA and

other stakeholders negotiate an agreement for acceptable emission standards for

logging activities within OU3.

Given the limited amount of time available each year for operation and the

possibility that the equipment may need to operate at less than maximum

production rates, the remediating of OU3 will be a lengthy process. The project

team estimates it may take 10 years (or more) to complete the work. Therefore,

it is recommended that an implementation plan be developed, which prioritizes

the areas to be treated within OU3.

All biomass material (logs, limbs, tops, etc.) resulting from timber harvest

operations in OU3 can either be disposed (landfilled) at the mine site (or other

area) or processed in a permanent utilization structure that could be located

within OU3 at the former mine site. The permanent facility will have equipment

for unloading log trucks, and the primary operation within this permanent

utilization structure will be debarking the tree stems.

The resulting bark will either be used as boiler fuel (at a boiler location to be

determined) or landfilled at the mine site. The debarked stems will be cleaned

with water and tested for levels of asbestos fibers. At this point, the effectiveness

of debarking and water treatment in removing asbestos fibers is unknown.

Neither is there a known, cost-effective test for identifying asbestos levels on

debarked and water-cleaned stems. If/when such protocols are developed, the

cleaned stems that meet the specifications for maximum levels of asbestos can

then be certified by the landowner as being acceptable for sale to commercial

users. For example, the sawlogs could be sold to sawmills in the region. Also,

the smaller pulpwood size stems could be chipped into pulp chips on site or sold



as stems and chipped at a location of the buyer’s choosing. Similarly, hog fuel

(ground bark, limbs, tops, etc.) could be utilized by biomass boilers in the region.

1.3.2 Forest Floor Duff Remediation Plan

The project team considered several technologies with respect to removing forest duff

from OU3. They included machines developed and tested in Europe for removing

topsoil from forests contaminated by a nuclear accident and a combination industrial

vacuum and portable conveyor system for moving forest duff from the forest to a central

collection area. The project team concluded that none of these technologies seem

promising for application in OU3 for the following reasons:

The very steep terrain in OU3 will limit the ability of the equipment to operate as

designed.

The large area of very steep terrain in OU3 means after the removal of forest

duff, severe erosion and perhaps contamination of areas outside of OU3 is

possible in run-off coming from OU3.

The forest duff (and underlying soils) in OU3 are likely to be shallow and rocky in

many areas. To the extent these conditions exist, it will limit the ability of some

equipment to perform as expected.

There is an unknown level of asbestos that is likely to be naturally occurring in

the minerals soils in the region. Thus, efforts to measure the amount of

asbestos in the soils and forest duff before and after forest duff remediation

treatments are likely to be confounded by “naturally occurring” asbestos.

Given the preceding considerations, the project team recommends that the strategy for

developing a forest duff remediation plan follow the lead of the US EPA in making

recommendations for institutional controls (administrative and legal controls that help

minimize the potential for human exposure to contamination and/or protect the integrity

of the remedy). The individual landowners within OU3, will then be able to use the

established institutional controls in developing their own remediation plans.

1.4 RECOMMENDATIONS

The following is a list of conclusions and recommendations:

The plans presented here are judged to be technically feasible based on the

project team’s experience and on research conducted as part of this study.

However, given the unique nature of OU3, the remediation plans have not been



proven in the field. Therefore, field testing is recommended to confirm the

feasibility of the remediation plans recommended in this report.

The tree inventory estimates for OU3 presented in this report are broad

estimates based on regional average per acre volumes. A more accurate

inventory of tree volume in OU3 is needed. Therefore, a silvicultural inventory

(timber, stand composition, fuel type, other vegetation, etc.) of OU3 is

recommended.

A detailed analysis of the existing road system in OU3 is needed. Key parts of

this analysis should include the ability of trucks to deliver materials from all parts

of OU3 using the existing forest road system rather than having to use Highway

37. Also, given the recommendation to haul stems from landings to the central

processing facility in lengths as long as possible, an assessment of the maximum

log length that can be transported on the existing road system using conventional

log trucks is needed.

A system for identifying the highest priority areas for treatment should be

developed. Potential criteria for selecting high priority areas are: 1) those found

to have the highest concentrations of asbestos fibers; 2) those already readily

accessible by existing roads; 3) those areas judged to have the greatest potential

for wildfire or where broad areas of trees have been killed by insects or disease.

Research and field level testing are needed to determine the effectiveness of

reducing the release of asbestos fibers by operating logging equipment under the

controls proposed in the remediation plan.

USEPA testing efforts up to this point have only determined that asbestos is

found on the bark on the main stem of the tree. While it stands to reason that the

fibers would also be found on other parts of the tree (e.g., limbs, tops, needles,

etc.) testing should be completed to confirm this assumption.

A program for providing the residents of the region with firewood from OU3

should be considered. This program would allow existing firewood contractors to

gather and provide firewood that is dry and certified to be free of asbestos fibers.

This effort is expected to eliminate what is believed to be a current and common

practice among residents of the area − going into the OU3 area, cutting firewood,

bringing it back to town, and burning it in their stoves, which potentially results in

recontamination of areas that have already been cleaned of asbestos.

More research is needed to determine whether it is preferable to install a boiler

and turbine generator within OU3 (e.g., at the former mine site), which would

allow utilization of biomass for hog fuel without the additional transport cost and



risk of contamination in areas outside OU3. Or would it be preferable to utilize

the hog fuel at an existing (or to be developed boiler) that would require the

transport and storage of asbestos contaminated biomass on roads and at a

location outside the borders of OU3?

More research is needed to determine the environmental impacts associated with

shipping asbestos contaminated logs, chips, barks, etc. in specially designed

covered trucks.

Testing is needed to determine the effectiveness of sprayed water in removing

asbestos fibers from debarked logs.

Testing and research are needed to identify procedures that can be employed to

quickly and accurately assess the presence of asbestos fibers on the surface of

materials (i.e., debarked logs).

Testing is needed to determine if the use of a water misting system on a landing

to encase tree stems in a sheath of ice is effective in controlling asbestos. If such

a system proves to be effective, additional testing should be conducted to

determine if it is feasible to use equipment similar to the snow making equipment

used at ski resorts to encase entire standing trees in a sheath of ice that will

serve as protection against the release of asbestos fibers during timber

harvesting operations.


CHAPTER 2 – THE OPERATING ENVIRONMENT

The purpose of this section is to describe the physical features of the area surrounding

the mine site, including the terrain, road systems, and density of existing tree

vegetation. In addition, the levels of asbestos found during EPA testing in OU3 are

described.

2.1.1 Existing Tree Vegetation

For this study, no inventory of trees in OU3 was completed. Instead, the team used

data from the USFS Forest Inventory and Analysis (FIA) database to estimate average

tree densities by species and diameter class (on a per acre basis) in the forests in the

OU3 area. FIA data is based on permanent inventory plots that were established over

80 years ago. There is roughly 1 plot for every 6,000 acres of forest land in the United

States. Each plot is revisited about once every 10 years, at which time measurements

of tree growth, mortality, harvest, etc. are taken. The most recent measurements taken

in Montana were completed between 2003 and 2009.

Data from the FIA website was retrieved using the mine site as the center of a 20 mile

radius area. The specific information collected included the number of timberland

acres in that region, total number of trees, and total volume. That data was converted

to averages “per/acre”. The “per/acre” values were then applied to the 35,000 acres in

OU3.

It is important to note that this process is likely to overstate the number and

volume of trees in OU3 since it is based on the assumption that all of the acres in

OU3 are the same as the “average” of the broader region from which the FIA

sample was taken. In other words, it does not account for areas within OU3 that may

have been harvested recently and therefore do not reflect the “average” forest

conditions, or areas on the southern part of OU3 that have little tree vegetation because

they are located on south facing slopes. Completing a more accurate inventory of OU3

was beyond the scope of this project.

As shown in Table 3, there is estimated to be, on average, 611 trees per acre. Of that

amount, on average, about 440 (or about 72 percent) are trees that are less than 5

inches in diameter at breast height. Douglas fir and Western Larch are the most

common species. About 4 percent of the total standing trees are standing dead trees.

Given that OU3 is about 35,000 acres in total size, the estimated total number of trees

in the area is about 21.0 million (after excluding about 1 square mile or about 640 acres

for the mine site where there are no trees). Of that amount, about 6.0 million are

greater than 5 inches in diameter at breast height and about 1.3 million are greater than

11 inches in diameter at breast height (or what would often be considered a sawlog size

tree).

Chapter 2 – The Operating Environment


TABLE 3 – ESTIMATED “AVERAGE” NUMBER OF STANDING TREES

PER ACRE IN OU3 BY SPECIES AND DIAMETER CLASS

Tree Diameter Class

Species

1.0 to 2.9

3.0 to 4.9

5.0 to 6.9

7.0 to 8.9

9.0 to

10.9

11.0 to

12.9

13.0 to

14.9

15.0 to

16.9

17.0 to

18.9

19.0 to

20.9

21.0 to

28.9 29+ Total

DF 92 53 24 15 10 6 5 3 2 1 1 1 213

PP 2 5 2 1 1 1 0 0 0 0 1 0 13

TF 48 7 10 7 4 3 2 1 0 0 0 0 81

HM 3 3 2 3 1 0 0 0 0 0 0 0 13

WP 0 0 0 1 0 0 0 0 0 0 0 0 1

ES 2 2 1 1 0 0 0 1 0 0 0 0 7

LP 10 18 10 5 4 3 2 2 1 0 0 0 54

WL 102 3 14 8 3 1 0 0 0 0 0 0 130

RC 77 12 4 1 1 0 0 0 0 0 0 0 96

Other 2 0 0 0 0 0 0 0 0 0 0 0 2

Total 338 102 67 43 24 15 9 6 3 2 2 1 611

NOTE: DF = Douglas fir; PP = Ponderosa Pine; TF = True firs; HM = Hemlock; WP = Western White Pine; ES = Engelmann Spruce; LP = Lodgepole Pine; WL = Western Larch; RC = Western Red Cedar; and Other = all other miscellaneous species

In terms of volume, rather than number of trees, Table 4 shows that there is an

estimated 65.4 million cubic feet of standing trees in OU3. Note that at the bottom of

the table, the cubic volumes have been converted into a total of roughly 850,000 bone

dry tons (BDT). The conversion is based on a factor of 26 bone dry pounds per cubic

foot. In addition, the cubic volume has been converted into board feet. When the

volume is expressed in board feet it is estimated to be about 425 million board feet

(MMBF) of standing trees in OU3. Please note that this estimate is based on a rough

conversion factor between cubic feet and board feet that does not account for different

conversion factors as tree size changes.

About 38 percent (317,000 bone dry tons) of the total volume is in pulpwood size trees

that are less than 11 inches in diameter at breast height. Note the 317,000 ton total

includes an estimated 47,000 bone dry tons of bark. Douglas fir and Western Larch

trees account for about 60 percent of the volume. Given that OU3 is about 35,000

acres in size, the estimated average per acre volume of standing trees is about 1,900

cubic feet, 25 bone dry tons, or 12.4 thousand board feet.



TABLE 4 – ESTIMATED CUBIC FOOT VOLUME OF STANDING

TREES IN OU3 BY SPECIES AND DIAMETER CLASS (CUFT MILLIONS)

Tree Diameter Class

Species 5.0 to

6.9 7.0 to

8.9 9.0 to 10.9

11.0 to 12.9

13.0 to 14.9

15.0 to 16.9

17.0 to 18.9

19.0 to 20.9

21.0 to 28.9 29+ Total

DF 1.98 2.97 3.78 3.89 4.12 3.73 2.60 2.32 1.21 1.68 28.28

PP 0.12 0.15 0.42 0.34 0.14 0.26 0.53 0.25 1.79 0.00 3.99

TF 0.96 1.58 1.42 2.34 1.41 1.03 0.50 0.26 0.00 0.00 9.51

HM 0.17 0.61 0.43 0.08 0.04 0.00 0.00 0.00 0.00 0.00 1.33

WP 0.01 0.08 0.00 0.21 0.00 0.15 0.00 0.32 0.00 0.00 0.78

ES 0.08 0.30 0.15 0.26 0.47 1.07 0.32 0.44 1.26 0.00 4.36

WL 0.61 1.22 2.14 1.94 2.10 2.39 0.62 0.00 0.00 0.00 11.02

LP 1.29 1.64 1.04 0.26 0.00 0.00 0.00 0.00 0.00 0.00 4.23

RC 0.45 0.33 0.44 0.18 0.00 0.00 0.00 0.39 0.00 0.00 1.79

Other 0.00 0.00 0.00 0.06 0.00 0.00 0.00 0.00 0.00 0.00 0.06

Total CUFT 5.67 8.89 9.81 9.56 8.28 8.63 4.57 3.98 4.26 1.68 65.35

Total Converted to BDT 73,759 115,598 127,595 124,276 107,680 112,172 59,426 51,755 55,409 21,902 849,572

Total Converted to MMBF 37 58 64 62 54 56 30 26 28 11 425

2.1.2 Road Density

As shown in Figure 2, the existing road system in OU3 is fairly well distributed

throughout the northern portion of the area, but relatively few roads exist in the southern

portion of the area. Based on the project team’s cursory analysis, there are

approximately 95 miles of road in OU3, excluding the main highway on the southern

boundary of OU3 and any roads directly within the mine area. This means that the road

density in OU3 is an estimated 1.75 (road density = miles of road per square mile of

land area).

As will be described later in the report, the project team has recommended that all

material harvested in OU3 be processed for utilization (or disposed of) at the former

mine site. Based on a review of the aerial photos of OU3, it appears that the road

system in the northwestern part of OU3 does link directly to the mine site, but a portion

of that road system is outside the OU3 boundary. The project team recommends that

all material harvested in OU3 be transported to the mine site on the existing

forest road system rather than along the eastern and southern boundaries of OU3

– parts of which are a major state highway (Highway 37).

This policy/procedure/strategy will mitigate increased log truck traffic on the highway

and reduce the cost of containing loads for transport on public roads. The project team

recommends a more detailed analysis of the road system in OU3 in a later phase

of study. Note, however, that if OU3 is expanded, then hauling contaminated material



on major public roads may become necessary. More research is needed to determine

how effective specially designed log trucks with “curtain sides” to enclose the logs might

be in limiting the release of asbestos fibers during transport.

2.1.3 Topography

The project team was unable to visit and tour the OU3 area. However, a preliminary

analysis of the topography of the site (see Figure 3) shows that the terrain in OU3 is

very challenging, especially in the western portion of the area. Note that the areas

shaded in blue are those judged to be where the terrain is less challenging. As shown

in Figure 3, generally only the valley bottoms and mountain tops contain the gentler

sloped areas. The ability of logging equipment to operate on slopes is discussed in

greater detail in Chapter 4.

2.1.4 Asbestos Levels

In November 2004, a research team from the University of Montana collected samples

from standing trees at seven locations in the vicinity of the W.R. Grace mine site and

one from a control tree in Albany, NY. The results were published in a study5 and are

shown in Table 5, which indicates that the number of Amphibole fibers per square

centimeter of bark ranged from a low of zero for the control tree in New York and one

tree tested in Libby at the Asa Wood Elementary School to a high of 260 million fibers

per square centimeter of bark on a lodgepole pine tree near the former pump house at

the W.R. Grace mine site.

TABLE 5 – CONCENTRATIONS OF ASBESTOS FIBERS

IN TREES IN AND NEAR OU3

Sample Point Location Description Type of Tree

Amphibole Fibers/cm2 of

Bark

Location 1 - Sample 1A Near the former pump house at the W.R. Grace mine Lodgepole Pine 100 million

Location 1 – Sample 1B Near the former pump house at the W.R. Grace mine Lodgepole Pine 260 million

Location 1 – Sample 1D Near the former pump house at the W.R. Grace mine Larch 40 million

Location 2 Just outside the mine property along Raney Creek Road Lodgepole Pine 110 million

Location 3 – Sample 3B Near the mine access gate on Raney Creek Road Ponderosa Pine 14 million

Location 4 Albany, NY Pine None detected

Location 5 – Sample 11 Along railroad ~ 7 miles east of Libby, Montana Ponderosa Pine 5.8 million

Location 7 – Sample 18 Libby Middle School Track Douglas fir 0.25 million

Location 8 – Sample 23 Asa Wood Elementary School Larch None detected

5 Trees as Reservoirs for Amphibole Fibers in Libby, Montana. Tony J. Ward, et al. 2006. Science of the Total

Environment. August 15, 367(1): 460-5.



In addition to the University of Montana study, the Montana Department of

Environmental Quality and the Montana Department of Natural Resources and

Conservation commissioned a study to measure the levels of asbestos contamination in

tree bark and forest duff in a timber sale area. The study was completed by Tetra Tech

EM, Inc. and was located in the Upper Flower Creek Timber Sale Area, which is located

south of Libby, Montana on land owned and managed by the State of Montana.

Samples were collected from 10 trees and 10 areas of forest duff in November 2011.

The results are shown in Table 6.

TABLE 6 – CONCENTRATIONS OF ASBESTOS FIBERS IN TREES AND FOREST

DUFF AS MEASURED AT A TIMBER SALE LOCATION

Sample Type Sample Number

Asbestos Fiber Count

Asbestos Concentration Unit of Measurement

Tree 1 8 226,298 structures/cm2

Tree 1 ND < DL structures/cm2










Duff 1 ND < DL structures/gram of dry weight

Duff 2 2 5,700,000 structures/gram of dry weight










*DL refers to Detection Limit

Finally, the USEPA completed a study that measured the levels of asbestos in forest

soil, tree bark, and forest duff material along a number of transects extending radially

from the mine site. The results are shown in Table 6A



TABLE 6A – ASBESTOS FIBER LEVELS - USEPA TESTING

Tree Bark Duff Material

Transect ID

Number of Structures

Surface Loading (M’s/cm2)

Number of Structures

Concentration (M’s/gram)

SL15-15 0 0 3 19

SL15-16 0 0 0 0

SL45-15 3 0.03 1 9

SL45-16 0 0 0 0

SL75-15 30 0.26 7 64

SL75-16 9 0.08 n/a n/a

SL135-15 13 0.12 8 61

SL135-16 19 0.18 2 18

SL195-15 50 0.53 4 35

SL195-16 3 0.03 1 10

SL315-15 2 0.02 0 0

SL315-16 5 0.04 3 18

Figure 1A shows the locations of each transect.

FIGURE 1A – LOCATION OF USEPA TREE BARK AND FOREST DUFF

MEASUREMENT TRANSECTS

(THE CENTER POINT IS THE FORMER MINE SITE)



FIGURE 2 – IMAGE OF EXISTING ROAD SYSTEM IN OU3 AREA

(WHITE SHADED AREA = OU3; RED LINES = EXISTING ROADS)



FIGURE 3 – TOPOGRAPHY IN OU3

(BLUE SHADED AREAS ARE WHERE THE SLOPE IS ESTIMATED TO BE LESS THAN 15 PERCENT TO 20 PERCENT)

Libby, Montana

W.R. Grace Mine Site Operational

Unit 3


CHAPTER 3 – REMEDIATION PLANNING APPROACH

The project team has organized the remediation plan into two distinct planning efforts:

1. Standing Tree Remediation Plan – all activities associated with remediating

areas contaminated with standing trees containing asbestos fibers on the bark.

2. Forest Duff Remediation Plan – all activities associated with remediating the

forest floor (the organic duff layer).

Given the unique requirements of this remediation effort and the limited budget for this

phase of the project, the approach taken was to develop remediation plans based on a

combination of the project team’s experience and project specific research completed

during the course of the study. Thus, the plans presented here are being considered

“theoretical” because while the procedures and technologies recommended in this study

have been used in other applications, they have not – to our knowledge – been used for

the remediation of asbestos from standing trees and forest duff. In other words, the

procedures and technology recommendations made in this report have not yet been

tested and proven in the field for the specific purpose of asbestos remediation from

standing trees and forest duff. Therefore, throughout the report, the project team has

made recommendations about issues that, in the team’s judgment, need validation

based on field testing.


CHAPTER 4 – STANDING TREE REMEDIATION PLAN

4.1 STANDING TREE REMEDIATION PLAN OBJECTIVES

The purposes of the standing tree remediation plan are to:

1. Develop a “remediation alternatives” list that identifies a number of possible

remediation approaches;

2. Analyze these alternatives to determine the best approach for this application,

(i.e., the one that captures and removes the most contamination);

3. Plan out the best approach for the remediation process in a step-by-step format ;

4. Describe any required modifications to processing equipment and processing

techniques to ensure worker safety and maximize containment of the asbestos

fibers;

5. Identify all other necessary best management and safe remediation practices.

The goals of this effort are that plan implementation will result in:

1. Reduction of fuels in the event of a wildfire in OU3;

2. Utilization (if possible) of contaminated material;

3. Continued public forest use of OU3 with minimal restrictions.

4.2 TIMBER HARVESTING TECHNOLOGY

Figure 4 illustrates the processing steps (areas shaded in light green) involved in

harvesting and processing trees. Listed below each processing step area variety of the

technology option(s) that can be used to complete the processing step (the white

boxes). Each of the technology options shown at each step were considered as part of

this study. However, the blue arrows indicate the technology options judged to be best

suited for removal of the asbestos-impacted standing trees in OU3. Note that debarking

is generally not a common processing step in timber harvesting. It is included here

because removing the bark within the OU3 area reduces the probability of

contaminating other areas during transport.

Following Figure 4 is a general discussion section about the various technologies

selected for consideration. The next section describes the modifications needed to be

Chapter 4 – Standing Tree Remediation Plan


made to the equipment or operating procedures in order to perform the procedures in

OU3 to achieve the safest work environment for the workers, while also capturing and

containing the asbestos to the greatest extent possible.

FIGURE 4 – DIAGRAM OF THE TIMBER HARVESTING PROCESS AND TECHNOLOGY OPTIONS FOR EACH STEP

4.2.1 General Discussion of the Technologies Selected

Regarding Figure 4, it is important to note that whole-tree harvesting is the logging

system that would be employed. Whole-tree harvesting refers to the practice of felling

trees and then moving the entire tree (i.e., limbs and top still intact) to a central

processing area where the limbs and top are removed and the tree is merchandised into

logs. The other common logging system is known as cut-to-length, and it involves the

processing of the tree into logs (i.e., removing the limbs, tops, and cutting logs to length)

at the area the tree is felled.

A key difference between whole-tree harvesting and cut-to-length is that most of the

limbs and tops accumulate at the centralized processing site (i.e., the landing) when

using whole-tree, rather than being scattered across a large area when using cut-to-

length. Therefore, an advantage of whole-tree for this application is that much of the

material to be reclaimed will already be concentrated in one location.

Wheeled Harvester

Tree Felling

Cable Logging

Extraction

Wheeled Ground-Based Skidding

Tracked Ground-Based Skidding

Wheeled Forwarding

Truck Loading

Tracked Excavator

Merchandising (Delimbing)

Processor Stroke-Boom Delimber

Hauling

Conventional Log Truck

Hand felling with Chainsaw

Tracked or Walking Feller Buncher

Tracked Harvester

Wheeled Feller Buncher



Figure 5 – a dangle-head harvester which is typically used for felling, delimbing, and cutting logs to length.

Timber Felling 4.2.1.1

The process of timber felling is simply severing a standing tree at the base of the stem

so that the tree falls to the ground.

In the past this process was commonly

completed by a person using a chainsaw

in an activity called hand felling. While

hand felling allows for a great deal of

flexibility in the types of terrain and tree

sizes that can be processed, use of hand

felling is less productive than mechanized

tree felling systems. It is also the most

hazardous timber harvesting activity

because workers can be injured by falling

branches, tree tops, or the tree itself, as

well as sustaining injuries by the

chainsaw itself. In addition, the hand

felling application could potentially

increase asbestos exposure to workers as the tree is felled and hits the ground.

Therefore, given the danger with hand felling and the increased potential to asbestos

exposure by workers, hand felling was not considered a viable option for OU3. In most

modern logging operations, the timber felling step is accomplished by a mechanized

piece of equipment with a machine operator controlling a cutting device and the

direction of the tree’s fall from an enclosed cab. The two basic types of machines are

harvesters and feller bunchers. Harvesters: In cut-to-length systems, the machine that

accomplishes timber felling is called a harvester because it not only cuts the tree down,

it also delimbs the tree, and cuts logs to specified lengths from the tree. Figure 5

shows a wheeled harvester at work, although harvesters can also be mounted on

tracked vehicles. Some harvesters are equipped with self-leveling cabs. A knuckle

boom is used to reach out to individual trees, rather than driving up to each tree. One

disadvantage of harvesters is that they cannot effectively process trees with multiple

stems. One benefit of using harvesters is that the process of delimbing and topping

trees right at the stump creates a bed of slash on which the harvesters and forwarder

can operate. Operating the equipment on the slash bed rather than bare ground

reduces soil disturbance. However, given the likelihood of asbestos being on the limbs

and needles and therefore, the increased potential for asbestos to be in the slash mat,

the action of the equipment would probably cause the asbestos particles to become

airborne. Therefore, a harvestor system has not been considered further for this

technology assessment. The project team recommends that additional testing be



completed to determine definitively whether asbestos is also found on the limbs

and needles.

Feller Bunchers are the second type of commonly used mechanized tree felling

equipment. The key differences between harvesters and feller bunchers are that feller

bunchers are only used for cutting, holding, and placing stems on the ground.

Feller Bunchers are typically mounted on either wheeled vehicles or tracked vehicles

(see Figure 6). When mounted on tracked vehicles, feller bunchers often have

self-leveling cab capabilities to ensure that the machine can be safely operated on

steep slopes. Another advantage of tracks is that the weight of the machine is

distributed over a relatively large surface area, which means that ground pressure levels

are low, and therefore, the machines can operate on loose and wet soils while causing

little soil disturbance. In addition, when feller bunchers are mounted on tracked

vehicles, they typically have a swing-boom that reaches out to each tree rather than

driving the machine to each tree in order to fell it (see Figure 6).

Note from Figure 6 that feller bunchers have accumulator arms in which several stems

can be collected (i.e., a “bunch”). Wheeled feller bunchers can only be operated on

gentle terrain (less than 25% slopes). Tracked feller bunchers with self-leveling cabs

can operate on much steeper slopes (up to 50%) and therefore would be best suited to

the rugged terrain found in OU3.

Another advantage of feller bunchers for this application is that the machine can control

the direction and speed with which trees are felled. Therefore, since the operators will

probably be instructed to more carefully place the trees on the ground, they can operate

the equipment in such a way as to reduce the chances for the asbestos fibers to

become airborne. The project team recommends that a tracked feller buncher be

used to harvest trees in OU3.



FIGURE 6 - SWING BOOM FELLER BUNCHER

FIGURE 7

Figure 7 - John Deere Prototype Walking Forest Machine



Please note that while a tracked feller buncher has been recommended as the preferred

technology for OU3, the project team has also made inquiries to John Deere about

using one of their prototype walking forest machines (see Figure 7). These machines

were developed in the early 1990s, and only two were ever built. They were designed

to be able to navigate in very difficult (steep, rocky) terrain. One of the prototype

machines has accumulated over 2,000 working hours during machine testing.

One of the potential advantages to John Deere of using this machine to fell the timber in

OU3 is giving John Deere a high profile application to demonstrate the capabilities of

their machine. Depending on the terms of any agreement reached with John Deere, it

might reduce or eliminate the costs associated with purchasing equipment needed to

complete remediation efforts in OU3. In addition, the walking forest machine is more

likely to be able to operate in the extreme terrain areas that a tracked feller buncher

might have difficulty navigating.

Extraction 4.2.1.2

Extraction is the process of moving the tree from the forest area (i.e., stump) to a central

processing area (i.e., landing). The following describes each type of extraction process.

Forwarding is the process of moving logs from the forest to a landing by carrying them

completely off the ground. The machine used to complete that process is called a

forwarder (see Figure 8). Forwarders are typically wheeled machines with an enclosed

operator cab and a log bunk for storing logs. The machines are usually self-loading and

are designed to carry the logs completely off the ground.

While the “off-the-ground” aspect of forwarding could be considered advantageous

because it creates less forest duff disturbance and thereby reduces the amount of

airborne asbestos, the advantage is minimal in OU3. First, the very steep terrain in the

vast majority of the area limits their use only to areas with less than 40 percent slope.

Second, these machines are most frequently designed to work in tandem with a cut-to-

length harvester. While some forwarders are designed to move tree-length stems,

these machines are very large and not well suited to operating on steep slopes. Thus,

given the project team’s recommendation of a whole-tree logging system, a typical

forwarder machine would not be well matched with the project team’s other technology

selections for processing the timber in OU3.



FIGURE 8 – WHEELED FORWARDER

Skidding is the process of moving logs or whole trees from the forest to a landing by

dragging them on the ground. A skidder is the name of the machine used for skidding.

A number of machines can be used to skid logs, including cable, grapple, clam bunk,

and wheeled and tracked. Cable skidders are either wheeled or tracked. and they

include a winch and cable that must be attached to each log by an operator who would

have to be outside of the enclosed cab. Grapple skidders are generally a wheeled

machine with a set of bottom-opening grapples that are used to grab, assemble, and

hold a load of logs as they are skidded to a landing. The project team recommends

that to the extent allowed by the terrain in OU3, grapple skidders be used. The

primary reason for this technology selection is that the operator of the grapple skidder is

able to work from inside the enclosed cab of the machine and therefore, exposure to

airborne asbestos fibers is limited.

Cable Logging is the process of using a system of overhead cables, support

towers/trees, and winches to move whole-trees or logs from the forest to the landing.

Four common types of cable systems are the highlead, standing, running, and live

systems. All are commonly used in terrain that is too steep for the safe operation of

wheeled or tracked vehicles. Aside from the advantage of being able to operate on

nearly all terrain, another advantage of cable logging is that, under the right conditions,

a significant portion of the stems/logs are often held well above the ground, which

reduces disturbance of the forest duff.



Figure 9 – Cable Yarding System

Figure 10 – Processor

For the sections of OU3 that are too

steep to safely operate wheeled or

tracked extraction equipment, the

project team recommends the use of

a cable logging system, see Figure 9.

Please note that the use of such a

system requires workers to hook the logs

to the cable system and to unhook the

logs at the landing. These workers

would not be in an enclosed cab. Thus,

additional personal protective equipment

(PPE) would be required for these

workers.

Merchandising – Delimbing 4.2.1.3

Merchandising is the process of removing the parts of the tree (e.g., limbs, tops, rot,

crook, sweep, etc.) so that the remaining pieces are logs (or pulpwood) that meets a

buyer’s specifications.

One piece of equipment

commonly used for

delimbing is a processor,

see Figure 10. It is typically

mounted on a knuckle-boom

and an excavator base. The

processor is designed to

remove tree limbs and to cut

logs to length, but it cannot

fell trees. A set of round

feed rolls are used to move

the log through a set of

delimbing knives. A bar saw

is also part of a processor,

and it is used to cut the log

to length after the limbs

have been removed. Most

heads are also equipped



Figure 11 - Stroke Boom Delimber

with sensors for measuring the length and diameter of the log being processed.

Another piece of equipment

used for delimbing and

topping is a stroke boom

delimber, see Figure 11. It

is a tracked excavator with a

boom, two grapples, and a

saw mounted on it. The

front grapple will grab a

stem near the middle of it’s

length and place the butt of

the stem in the rear grapple.

The rear grapple then holds

the stem in place while the

stem is pulled through the

delimbing knives.

The project team has recommended the use of a stroke boom delimber because it

is generally a lower cost machine to operate. However, a processor is also

acceptable for use in the OU3 area. Please note that the project team recommends

that the stems be cut to the longest lengths possible. This practice will minimize

handling since fewer pieces will be produced.

Truck Loading 4.2.1.4

The purpose of log loaders is twofold: 1) For sorting logs into different groups based

on differences in size, quality, species, etc. and 2) for loading logs onto trucks, rail cars,

etc. so that they can be transported to their destination. Loaders are typically mounted

on either a wheeled base or a tracked machine. Wheeled machines of the “front-end”

loader type have the advantage of being fast and being able to handle large payloads in

a single “bite” of the grapple. However, they are not able to readily single out specific

logs for sorting, nor are they as stable as tracked machines. Therefore, wheeled

machines are not being recommended for this application since the landing areas are

likely to be relatively confined and could potentially have uneven terrain.

Tracked loaders (see Figure 12) are typically equipped with a knuckleboom that has

been specially designed for handling logs. It includes a grapple mounted to the end of

the boom that can grasp logs and fully rotate, which allows the operator to accurately

place logs on a truck. Most of these loaders also have a “heel” that allows for stable

handling of large and long length logs. The operator of the loader works within an



enclosed cab. The project team recommends that a tracked based loader be used

in OU3.

FIGURE 12 - TRACKED LOG LOADER WITH ROTATING GRAPPLE AND HEEL

Hauling 4.2.1.5

After logs and pulpwood sized material have been merchandised and sorted into groups

on a landing, they are normally hauled to a conversion facility for further processing into

various products. A variety of tractor and trailer configurations are used, but for

the purposes of transporting logs and pulpwood size material for this application

a standard log truck and pole trailer configuration are recommended (see Figure

13). This arrangement will allow for transporting stems in tree length form or in long-log

segments. Note that depending on the weight limits for the roads or on the type of

roads common in OU3, different axle configurations maybe be needed or a stinger-

steered trailer may be required. The advantage of these changes would be increased

payload and the ability to better navigate roads with sharp turns. More investigation of

these issues is recommended in a later phase of study.



FIGURE 13 – LOG TRUCK

4.2.2 Equipment & Operating Modifications Needed for OU3 Plan Implementation

This section describes the modifications to both normal equipment and normal

operating practices that will be required to operate within OU3.

General Approach 4.2.2.1

A normal procedure for remediating asbestos in, for example, buildings is to enclose the

entire area to be remediated within an atmospheric control structure so that asbestos

fibers that become airborne during remediation activities are captured within the

atmosphere controlled structure. However, the project team, after speaking with

numerous experts on topics including logging technology and asbestos remediation,

has concluded that a similar approach to harvesting trees in OU3 is not practical

because of the ruggedness of the terrain, the large land area to be treated, and the

height of the trees. All of these factors combine to make creating an atmosphere

controlled structure around tree felling, extraction, merchandising, loading, and hauling

activities highly impractical, if not impossible.

Therefore, the project team has focused on other methods for controlling and mitigating

the extent of asbestos released. These include:

1. Harvest Timing – All logging and hauling activities will be completed only during

periods of the year when: 1) the ground and trees are frozen (i.e., winter logging

only); or 2) when air temperatures are cool and relative humidity levels are high

enough to reduce dust. Of the two, timber harvesting during frozen conditions is

preferable. This precaution is expected to inhibit asbestos fibers from becoming

airborne during logging operations. However, testing is needed to determine the

extent of asbestos fiber release during timber harvesting operations under both

of these conditions.



2. Dust Control – As is common in many asbestos remediation efforts, a water

mist will be applied to the tree stems, limbs, tops, and other logging slash on the

landing areas. During times of the year when the ambient air temperatures are

below freezing, the use of a water mist is expected to “freeze” or “encase” the

vast majority of the asbestos fibers in place and thereby inhibit the fibers from

becoming airborne during logging operations. It is the project team’s

understanding that the water needed for this procedure would be available from

existing wells within the OU3 mine site.

3. Expanded “Dust” Control – If testing of air conditions during timber harvesting

operations as recommended in point one show that asbestos fiber levels are too

high, the project team recommends experimentation with an expanded dust

control effort. The concept would be to use equipment similar to the snow

making equipment used at ski resorts to mist standing trees with water/ice

crystals prior to timber harvesting operations. It is expected that this misting

would encase the trees in a sheath of ice and thereby reduce the release of

asbestos fibers. Testing is needed to determine the feasibility of this concept as

well as to determine the amount of water needed.

4. Standing Tree Remediation First – The objective of this project is to identify a

plan for remediating both standing trees and forest floor duff in OU3. The project

team recommends that standing tree remediation always be completed in an

area before any work on forest floor duff remediation is undertaken. Harvesting

trees in an area where the forest floor duff has already been treated would only

recontaminate the area.

5. Maximum Operating Speeds – While all work will be conducted only during the

times of the year when the ground is frozen and therefore minimal levels of dust

are expected, machine and truck operators will still be required to move and

operate the machinery at a work pace that will minimize dust generation. This

reduces opportunities for asbestos to become airborne during harvesting

operations to acceptable levels established by regulators.

6. Long Term Plan – Given all of the following:

The already large size of the OU3 area (~35,000 acres),

The chance that OU3 may become larger,

The project team’s recommendation that equipment be operated with a preference for safety and mitigating asbestos fiber release rather than for maximizing production,



The large amounts of biomass that will be generated as a result of implementing the plan,

Based on the preceding factors, the project team recommends that plans for

treating OU3 be considered on a long term basis – a minimum of 10 years and

most likely for as long as 10 years (or more) to treat the entire area.

Equipment Modifications 4.2.2.2

All equipment associated with timber felling, extraction, merchandising, truck loading,

and hauling (i.e., a tracked feller buncher, skidders, cable yarders, stroke boom

delimbers, log loader, and log trucks) will be modified so that each is equipped with a

positive air pressure system that will allow the operators to work in cabs without wearing

a respirator.

Operator Modifications 4.2.2.3

A site safety and health plan (SSHP) will be developed for all requirements to work

within the contaminated areas of OU3. The SSHP will likely include the use of

respirators while working outside of positive pressure controlled cabs.

The personnel working within contaminated areas of OU3 will be OSHA 40-hour trained

(Hazardous Waste Operations training as per 29 CFR 1910.120) and comply with all

requirements under this standard. All personnel will also be fully training in the standard

of the SSHP.

Monitoring 4.2.2.4

Procedures will be established for monitoring the release of asbestos fibers during

harvesting activities. These will include air monitoring to be conducted on the workers

and at the perimeter of the work area.

Monitoring may indicate airborne asbestos levels during logging that are higher

than currently allowed limits. The project team recommends that the USFS, EPA

and other stakeholders negotiate an agreement for acceptable air monitoring

requirements for logging activities within OU3.

A sampling and analysis plan (SAP) will be developed for use during the logging

activities to determine the required levels of PPE and engineering controls.


CHAPTER 5 – FOREST DUFF REMEDIATION PLAN

Forest duff is the material found on the floor of forests that typically consists of items in

two layers. The upper layer generally includes things such as twigs, needles, leaves

and other forms of vegetation that are dead, but have not yet decomposed. The

second, lower layer includes partially to fully decomposed forest litter that rests on top of

the mineral soil. Duff sampling at 9 locations completed in November 2011 in the Upper

Flower Creek Timber Sale area indicated that asbestos concentrations in the duff

ranged from no detectable limits to 12 million structures per gram of dry duff weight.

While the area sampled is not within OU3, the results provide an indication of the

asbestos levels that might be expected within OU3.

It should be noted that to the knowledge of the project team, the extent of asbestos in

the two forest duff layers is not known. In other words, the distribution of asbestos in

the undecomposed duff layer relative to the more decomposed layer is not known. Nor

are the baseline levels of “naturally occurring” asbestos in the region known.

5.1 FOREST DUFF REMEDIATION TECHNOLOGY

The project team is not aware of any well-established technologies for removing forest

duff from forested areas. However, there has been some research aimed at developing

such technologies. The following sections summarize the findings from those efforts.

5.1.1 Remediation of Northern Europe Forests

In 2002 a study6 was completed the Nordic Nuclear Safety Research Group (a.k.a.

Nordisk Kemesikkerhedsforskning). The purpose of the study was to identify

technologies available for planning countermeasures in the event of a nuclear accident

that caused widespread contamination of forests and forest duff. With regard to forest

duff remediation, the study made recommendations that the top few centimeters of the

organic layer (i.e. the whole undecomposed layer and the top portion of the

decomposed layer) be removed during treatments. The recommendation for

accomplishing this task was the use of a tractor-powered machine that was in

development at FSL in Denmark, which is the Danish Forest and Landscape Research

Institute (www.eldis.org). The machine could reportedly harvest the organic forest floor

6 Tools for Forming Strategies for Remediation of Forests and Park Areas in Northern Europe after Radioactive Contamination:

Background and Techniques. 2002. Lynn Hubbard et al. Accessed at:

www.nks.org/scripts/getdocument.php?file=111010111119792

http://www.eldis.org/

Chapter 5 -- Forest Duff Remediation Plan


layer with first requiring the total removal of stumps and other vegetation. The project

team was not able to find further documentation of the equipment, but apparently it

consisted of a rotating device mounted to the front of a wheeled piece of equipment

such as a tractor or skidder. The rotating device scooped up the forest duff and fed it to

a storage bin mounted behind the tractor. The depth of the rotating brush in the duff

layer was controlled by a set of wheels.

Given the very steep terrain found in OU3, the project team does not believe the

technology recommended in the Nordic study would be viable. In addition, the Nordic

study recommended that the technique not be applied in areas that a prone to erosion.

Again, given the steep terrain in OU3, the project team has concluded that attempting to

remove the duff layer is not a preferred option because of the potential for significant

erosion.

Another option identified in the Nordic study was “deep plowing” of forest soils. The use

of large scale wheeled or tracked equipment with specially designed plows allows the

plowing and removal of soil up to 1 foot deep. While all standing trees need to be

removed to apply this technology, stumps do not need to be removed. The project team

considered this technology within the context of OU3, but concluded it was not likely to

be viable given the steep terrain in the region and soils that in many areas of OU3 are

likely to be too shallow and rocky.

5.1.2 Combination Industrial Vacuum System and Portable Conveyor

The project team also considered industrial vacuum systems as a way to remove forest

duff from OU3. Several industrial vacuum manufacturers exist including Vector in

Milwaukee, Wisconsin and Multi-Vac in Union Grove, Wisconsin. The concept

considered was that the industrial vacuums could be used in conjunction with portable

conveyors to gather and transport forest duff to a central collection point. More

specifically, an industrial vacuum system would be mounted on a wheeled or tracked

vehicle and would include a large collection bin. The vacuum would then move around

a contaminated site collecting forest duff. Periodically the vacuum would unload the

material from the collection bin onto a portable conveyor system which would transport

the material to a centralized collection point.

The project team is not aware of this concept ever having been demonstrated in actual

field use. However, portable industrial vacuum systems have been used successfully

and portable conveyor systems have been tested in the field. The two have not been

used in conjunction with each other. Regarding the portable conveyor systems, field

trials were completed in 2008, which tested the feasibility of using portable conveyors to

move slash from timber harvest units to a centralized landing area. The tests were

conducted in the Lake Tahoe area.

Chapter 5 -- Forest Duff Remediation Plan


The results of the test are described in detail in a USFS research bulletin7 and in

abbreviated form here. Portable conveyors can be used in forest settings. They are

made up with a number of individual sections with each section being about 10 to 15

feet long. Such conveyors are available from several manufacturers and are being

used in construction, mining, and nursery industries for temporary material handling

tasks.

The conveyors tested in Lake Tahoe field tests were powered by hydraulics or electricity

and had the capacity to convey up to 20 tons of material per hour. They were set up in

a quarter acre timber harvest area and used to convey logging slash up a 17 degree

slope. The productivity of the conveying system ranged from 4 to 6 green tons per

hour. While the system worked in general a problem encountered was that many of the

slash pieces were too long or otherwise too big to fit on the conveyor with a good

likelihood of falling off.

In the context of OU3, the project team believes such a system might have a better

likelihood of being more effective because the material picked up by the industrial

vacuum system will be smaller in size and therefore less likely to fall off the conveyor.

However, given the low production rates observed in the trials and the much steeper

terrain in much of OU3, the technical and practical feasibility of such a system is

doubtful. A more detailed assessment of this possible technology is recommended in

later phases of study.

5.1.3 Beneficial Land Cover

A third option considered was the use of a beneficial land cover. This concept would

draw on the experience of a recent reclamation project near Aspen, Colorado8. In that

project, a mix of biochar and native grass seeds were applied to a barren slope that was

slowly eroding various toxins associated with mine tailings into Castle Creek at a

location just upstream from Aspen’s water treatment plant. The application of the

biochar and seed stabilized the soil in the slope and minimized erosion of soil into the

stream. In the Libby situation, the contamination is found in the forest duff rather than

the soil. Therefore, the utility of establishing a beneficial land cover is less clear.

Further investigation is recommended.

7 Tests of Biomass Removal Using Lightweight Portable Conveyors. June 2008. Bob Rummer, et al. Document

Number 0851-2809-MTDC.

8 From Barren to Beautiful at Aspen’s Hope Mine. September 10, 2011. Accessed at:

http://www.forestbusinessnetwork.com/7496/from-barren-to-beautiful-at-aspens-hope-mine/from-barren-to-

beautiful-at-aspens-hope-mine200/

http://www.forestbusinessnetwork.com/7496/from-barren-to-beautiful-at-aspens-hope-mine/from-barren-to-beautiful-at-aspens-hope-mine200/

http://www.forestbusinessnetwork.com/7496/from-barren-to-beautiful-at-aspens-hope-mine/from-barren-to-beautiful-at-aspens-hope-mine200/


CHAPTER 6 – MATERIAL UTILIZATION

Given the vast amount of biomass material (about 850,000 bone dry tons) that is

estimated to be located within OU3, a substantial need exists to utilize the biomass so

that it does not accumulate at the site. This chapter describes the project team’s

preliminary plans for utilizing the various forms of biomass that will be generated. Each

form of biomass that can potentially be utilized is described. First, however, several

general concepts related to utilization are discussed.

6.1 GENERAL UTILIZATION CONCEPTS

6.1.1 Establish a Permanent Utilization Structure

The project team recommends that a permanent structure be established within OU3

(most likely at the mine site) that will allow for processing of logs, pulpwood, chips, etc.

in an atmosphere controlled environment and which has equipment installed that is

capable of cleaning the resulting products (logs, etc.) and which can test the products to

insure that they can be certified to meet acceptable levels of asbestos prior to leaving

the site.

The project team currently envisions a relatively large structure (e.g., 200’ x 200’) so

that a variety of processing steps could be accomplished within the structure. The

building would be designed so that various pieces of equipment could easily be “rolled

in and rolled out” as the needs for processing material change over time.

At a minimum, the equipment needed in the structure would include a debarking

operation that would allow for removal of the asbestos contaminated bark, resulting in a

“clean” debarked stem that could be utilized in a variety of ways. The project team

recommends that a ring debarker be installed for this purpose.

Ring debarkers are able to very precisely remove bark and leave wood fiber. Other

debarking technologies, such as chain flail debarkers and rotary drum debarkers, rely

on more of a “brute force” approach for removing bark, which allows for relatively little

control over the amount of bark/wood fiber removed. In addition, those technologies

create excessive dust, with less opportunity for particulate control. Ring debarkers, in

contrast, already commonly use dust control procedures such as a water mist and

vacuum systems.

As described by Mr. Mike Dickinson, Regional Sales Manager for Nicholson

Manufacturing, Ltd., which manufactures ring debarkers, the systems are typically

installed at about 8 foot elevation, which allows for a combination of gravity, vacuum

Chapter 6 -- Material Utilization


pressure, and water mist to cause the bark and fine particles to drop into a system of

chutes, conveyors, and storage bins. Mr. Dickinson stated that 90 feet per minute is the

effective production rate for a ring debarker designed to handle the vast majority of the

trees in OU3 (a few trees over 35 inches in diameter would not be able to be

processed). The project team estimates that if all trees over 5 inches in diameter at

breast height were harvested and debarked, the debarker would have to run four

thousand hours per year for over 12 years to process all of the stems. The project team

also estimates that this would yield approximately 125,000 bone dry tons of bark.

The debarker and other equipment in the facility would be electrically powered.

According to Mr. Dickinson, the debarker and associated conveyors would require about

200 horsepower of electrical motors to operate. The debarker would need an infeed

conveyor at least as long as the longest stem that would be processed. At a minimum

this would be 40 feet, but could potentially be as long as 75 feet or more. The debarker

can be operated remotely using video cameras and control systems. This would help

reduce the potential for exposing operators to airborne asbestos.

In addition to the debarker, the permanent structure would need rolling stock (e.g., a

front end loader) for loading and unloading trucks, a stationary knuckleboom loader for

feeding logs to the debarker, and a cut-off saw for cutting stems to specified lengths.

Other, more specific, pieces of equipment that might be required are described in

Section 6.2, concerning specific products that might be produced

6.1.2 Site Control

Site control will be an overriding issue. In other words, the project team recommends

that none of the materials (logs, pulpwood, slash, chips, hog fuel, etc.) generated during

logging activities leave the OU3 area until: 1) after they have been certified to meet

specifications for acceptable asbestos levels; or 2) they are placed into specially

designed transport vehicles that mitigate the release of asbestos fibers during transport.

With respect to point 1, procedures for decontaminating products before allowing

them to be shipped out of OU3 will need to be developed. In addition, guidelines

for maximum allowable concentrations of asbestos fibers on the products will

have to be established.

6.2 SPECIFIC PRODUCTS THAT MIGHT BE PRODUCED

The following sections describe specific products that might be produced at the

permanent processing facility, as well as some of the specific support equipment that

would be needed.



6.2.1 Sawlogs

Debarked sawlogs that have been certified to meet acceptable levels of asbestos could

be sold to nearby sawmills. Aside from the previously described debarker and

permanent utilization facility, the additional equipment needed for the production of

sawlogs is a cut-off saw for cutting the tree length stems into log lengths as specified by

the buyers of the logs, rolling stock for moving, sorting, and decking logs, and

miscellaneous conveyor systems.

To establish an order of magnitude estimate of what the logs in OU3 might be worth, the

project team used the current volume estimate and did not account for any growth of the

trees that would occur over the time the harvests are being conducted. Thus, there is

an estimated 266 million board feet of timber in sawlog size trees (> 11” in diameter at

breast height). According to RISI’s July 2012 delivered log price reporting service, the

average delivered log price for all species in the Inland Region is about $275 per

thousand board feet. Assuming that the average haul cost is $75 per thousand board

feet, it has been assumed that logs could be sold from the gate of the OU3 processing

facility for an average value of $200 per MBF. This translates into an estimated value of

$53.2 million at current log market values. Those revenues could be used to offset the

timber harvesting, road maintenance, administrative and other costs.

6.2.2 Pulp Chips

Another potential product that could be produced at the facility is pulp chips, which

could be used as a feedstock in the manufacture of paper or for the manufacture of

panel products such as Medium Density Fiberboard (MDF). The production of chips

would require that debarked logs be processed in either a stationary or portable chipper.

The chipper would either need to be coupled to the debarking system and cleaning

system so that small trees could be diverted from the saw log production line into the

chipper, or a loader would need to be used that could pluck the small stems from the

debarking and cleaning operation and divert them into the chipper. Adequate storage

space would be needed so that downtime at the chipper would not also slow down the

operation of the debarker.

To establish an order of magnitude estimate of what the pulp chips might be worth, the

project team used the same procedures for estimating the volume of the small trees as

were used in the preceding section for sawlogs (i.e., no adjustments were made for tree

growth). However, an allowance was made for 15 percent of the weight of the small

trees being bark and for 5 percent of the small trees being utilized as firewood. The

result is that there would be an estimated 250,000 bone dry tons of chips produced.



Based on a survey of f.o.b. mill values for chips in the Inland Region completed by The

Beck Group at the end of 2011, the average value per bone dry ton was $100. For this

analysis, that value was discounted by 33 percent to a value of $67 per bone dry ton to

account for the OU3 region being further from a market than the mills that participated in

The Beck Group survey. The result is that the chips would have an estimated value of

$17.1 million at current market values. These revenues could be used to offset the

timber harvesting and other processing costs in OU3.

6.2.3 Hog Fuel

Technologies are proven and available for thermo-chemically destroying asbestos9.

Therefore, hog fuel is another product that could be produced at the permanent facility

and then utilized to produce steam and/or electricity. The location of such a user with

the appropriate technology for destroying asbestos has yet to be determined. However,

if such a user were found, the project team estimates that there would be approximately

125,000 bone dry tons of bark produced from the processing of saw logs and pulpwood

size trees. The bark could be sold as hog fuel. Assuming a delivered value of $35 per

bone dry ton, it is estimated that the bark would have a value of $4.375 million that

could be used to offset the costs of operating the debarker and transporting the bark to

the end user. An alternative to utilizing the bark as hog fuel would be to landfill the

material at a site to be determined within OU3.

6.2.4 Logging Slash

Like hog fuel, limbs and tops (logging slash) from the timber harvesting operations could

be processed in a portable horizontal grinder and subsequently used for hog fuel. The

current vision for this process would be to locate a horizontal grinder at the permanent

processing facility and to transport unground logging slash to the facility in for

processing into hog fuel. The limited budget for this project did not allow for more

detailed planning of how the limbs and tops can be transported.

Using a factor of 1 bone dry ton of logging slash produced for every thousand board feet

of timber produced, the project team estimates that approximately 425,000 bone dry

tons of logging slash would be produced. The analysis does not take into account any

growth of the trees that would occur over the life of the project. Assuming a delivered

value for this material of $35 per bone dry ton, it is estimated that the logging slash

would have a value of $14.9 million that could be used to offset the costs of collecting,

grinding, and transporting the material to the end user.

9 See: ARI Technologies, Inc. Thermochemical Conversion Technology (TCCT) at www.aritechnologies.com

http://www.aritechnologies.com/



6.2.5 Firewood

The Libby area was a recent recipient of a grant from the federal government to

implement a wood stove changeout program. The objective of the program was to get

citizens to replace their older, inefficient wood burning stoves with newer, more efficient

wood burning stoves. Many Libby area residents took advantage of the program, but

the results have not been as successful as anticipated. Part of the problem is that many

residents continue to burn green or uncured wood. Another issue is that OU3 is

frequently the source of their firewood. As a result, concerns are arising that, after all of

the clean-up effort that has occurred in Libby, recontamination may be occurring

because some of its citizens are burning asbestos contaminated wood in their wood

stoves.

One potential solution to this issue is to develop a firewood program for the residents of

the region to use OU3 certified asbestos-free wood. No analysis has been completed

as part of this project, but the costs for such a program are anticipated to be small as

long as the material handling and processing structure are in place and producing

materials like saw logs and pulp chips. The expected benefits include helping residents

of the region reduce their heating bills, cleaning up the air quality in the area, and

reducing the spread of asbestos into areas that have already been cleaned up.

Assuming that 5 percent of the pulp logs were diverted from the production of chips into

firewood, the project team estimates that over 12,000 cords of firewood would be

produced during the life of the project. Further analysis is needed to determine the

costs of producing the firewood and whether that amount is consistent with the volumes

that are consumed in the region.

6.3 BUDGETARY CAPITAL COST ESTIMATES

Table 7 provides a budgetary level estimate of the capital cost for establishing a

utilization facility. Please note that given the limited budget for this project, the

estimates shown here are largely taken from costs associated with past projects and

little effort was given to verifying these costs as they might apply to the specifics of

establishing a utilization facility within OU3. Much more detailed research is needed to

more accurately estimate the capital cost associated with a utilization facility.



TABLE 7 – BUDGETARY CAPITAL COST

ESTIMATE OU3 UTILIZATION FACILITY

Cost Item Description

Estimated Cost ($)

Building (200' x 200') 1,600,000

Rolling Stock (log loader and forklift) 350,000

Debarker and associated conveyors, decks, saws, etc. (used) 400,000

Portable horizontal grinder (new) 800,000

Total 3,150,000

6.4 ESTIMATED REQUIRED STAFFING LEVELS

Table 8 illustrates the estimated staffing levels for operating the permanent utilization

facility. With regard to timber harvesting operations, the staffing levels are estimated to

be no different than normal timber harvesting crews. Thus, a typical crew might consist

of 8 to 12 members depending on the type of logging equipment used.

TABLE 8 – ESTIMATED STAFFING REQUIREMENTS

AT PERMANENT UTILIZATION FACILITY

Staff Person

Number of

Staff Required Description

Supervisor 1 Oversee and manage utilization

facility operations

Project Safety

Coordinator

1 Ensure that safety protocols are in place and being

followed

Loader

Operator

1 Load/unload

trucks

Debarker

Operator

1 Operate

debarker

Log Clean Up

Operator

1 Operate system for cleaning debarked logs of

asbestos fibers

Test

Operator

1 Conduct tests to ensure debarked logs, chips, etc.

meet asbestos level specifications

Total 6

asbestos remediation plan for forested areas near libby, montana

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