Asbestos Remediation Plan for Forested Areas near Libby, Montana

Transcription

1 Asbestos Remediation Plan for Forested Areas near Libby, Montana Developed for: Lincoln County Port Authority Libby, Montana Final Report September 2012

2 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

3 Table of Contents Page CHAPTER 1 EXECUTIVE SUMMARY Introduction The Operating Environment Landowners Tree Biomass in OU Road System Asbestos Levels The Remediation Plans Standing Tree Remediation Plan Forest Floor Duff Remediation Plan Recommendations... 8 CHAPTER 2 THE OPERATING ENVIRONMENT Existing Tree Vegetation Road Density Topography Asbestos Levels CHAPTER 3 REMEDIATION PLANNING APPROACH CHAPTER 4 STANDING TREE REMEDIATION PLAN Standing Tree Remediation Plan Objectives Timber Harvesting Technology General Discussion of the Technologies Selected Timber Felling Extraction Merchandising Delimbing Truck Loading Hauling Equipment & Operating Modifications Needed for OU3 Plan Implementation General Approach Equipment Modifications Operator Modifications Monitoring... 32

4 Table of Contents CHAPTER 5 FOREST DUFF REMEDIATION PLAN Forest Duff Remediation Technology Remediation of Northern Europe Forests Combination Industrial Vacuum System and Portable Conveyor Beneficial Land Cover CHAPTER 6 MATERIAL UTILIZATION General Utilization Concepts Establish a Permanent Utilization Structure Site Control Specific Products That Might Be Produced Sawlogs Pulp Chips Hog Fuel Logging Slash Firewood Budgetary Capital Cost Estimates Estimated Required Staffing Levels... 41

5 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. THE BECK GROUP Page 1

6 Chapter 1 Executive Summary The OU3 area is part of the Libby Asbestos Superfund site that was established in 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 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 THE BECK GROUP Page 2

7 Chapter 1 Executive Summary 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 THE BECK GROUP Page 3

8 Chapter 1 Executive Summary 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 sides 1. 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 Asbestos Levels Asbestos levels on the trees in OU3 have been documented in several studies. For example, the US EPA completed a study 2 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 2 Libby OU3 Phase I Sampling and Analysis Plan. USEPA. Completed 9/7/11. THE BECK GROUP Page 4

9 Chapter 1 Executive Summary sample. Another study 3 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 study 4 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 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 Accessed at: DuffSampling-UpperFlowerCreekTimberSaleAreaFeb pdf THE BECK GROUP Page 5

10 Chapter 1 Executive Summary 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 THE BECK GROUP Page 6

11 Chapter 1 Executive Summary 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 THE BECK GROUP Page 7

12 Chapter 1 Executive Summary 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 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 THE BECK GROUP Page 8

13 Chapter 1 Executive Summary 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 THE BECK GROUP Page 9

14 Chapter 1 Executive Summary 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. THE BECK GROUP Page 10

15 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 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 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). THE BECK GROUP Page 11

16 Chapter 2 The Operating Environment TABLE 3 ESTIMATED AVERAGE NUMBER OF STANDING TREES PER ACRE IN OU3 BY SPECIES AND DIAMETER CLASS Species 1.0 to to to to to 10.9 Tree Diameter Class 11.0 to to to to to to Total DF PP TF HM WP ES LP WL RC Other Total 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. THE BECK GROUP Page 12

17 Chapter 2 The Operating Environment Species TABLE 4 ESTIMATED CUBIC FOOT VOLUME OF STANDING TREES IN OU3 BY SPECIES AND DIAMETER CLASS (CUFT MILLIONS) 5.0 to to to to 12.9 Tree Diameter Class 13.0 to to to to to Total DF PP TF HM WP ES WL LP RC Other Total CUFT Total Converted to BDT 73, , , , , ,172 59,426 51,755 55,409 21, ,572 Total Converted to MMBF 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 THE BECK GROUP Page 13

18 Chapter 2 The Operating Environment 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 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 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 study 5 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 Science of the Total Environment. August 15, 367(1): THE BECK GROUP Page 14

19 Chapter 2 The Operating Environment 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 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 ,298 structures/cm2 Tree 1 ND < DL structures/cm2 Tree 2 ND < DL structures/cm2 Tree 3 ND < DL structures/cm2 Tree 4 ND < DL structures/cm2 Tree ,862 structures/cm2 Tree ,793 structures/cm2 Tree ,873 structures/cm2 Tree ,436 structures/cm2 Tree ,287 structures/cm2 Tree 9 ND < DL structures/cm2 Duff 1 ND < DL structures/gram of dry weight Duff 2 2 5,700,000 structures/gram of dry weight Duff 3 1 7,300,000 structures/gram of dry weight Duff 4 ND < DL structures/gram of dry weight Duff 4 ND < DL structures/gram of dry weight Duff 5 ND < DL structures/gram of dry weight Duff 6 ND < DL structures/gram of dry weight Duff 7 ND < DL structures/gram of dry weight Duff 9 ND < DL structures/gram of dry weight Duff 8 ND < DL structures/gram of dry weight Duff ,000,000 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 THE BECK GROUP Page 15

20 Chapter 2 The Operating Environment Transect ID TABLE 6A ASBESTOS FIBER LEVELS - USEPA TESTING Number of Structures Tree Bark Surface Loading (M s/cm2) Number of Structures Duff Material Concentration (M s/gram) SL SL SL SL SL SL n/a n/a SL SL SL SL SL SL 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) THE BECK GROUP Page 16

21 Chapter 2 The Operating Environment FIGURE 2 IMAGE OF EXISTING ROAD SYSTEM IN OU3 AREA (WHITE SHADED AREA = OU3; RED LINES = EXISTING ROADS) THE BECK GROUP Page 17

22 Chapter 2 The Operating Environment FIGURE 3 TOPOGRAPHY IN OU3 (BLUE SHADED AREAS ARE WHERE THE SLOPE IS ESTIMATED TO BE LESS THAN 15 PERCENT TO 20 PERCENT) W.R. Grace Mine Site Operational Unit 3 Libby, Montana THE BECK GROUP Page 18

23 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. THE BECK GROUP Page 19

24 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 THE BECK GROUP Page 20

25 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 Tree Felling Hand felling with Chainsaw Tracked or Walking Feller Buncher Tracked Harvester Wheeled Feller Buncher Wheeled Harvester Extraction Cable Logging Wheeled Ground-Based Skidding Tracked Ground-Based Skidding Wheeled Forwarding Merchandising (Delimbing) Stroke-Boom Delimber Processor Truck Loading Tracked Excavator Hauling Conventional Log Truck 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-tolength. 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. THE BECK GROUP Page 21

26 Chapter 4 Standing Tree Remediation Plan Timber Felling 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 Figure 5 a dangle-head harvester which is typically used for felling, delimbing, and cutting logs to length. 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 THE BECK GROUP Page 22

27 Chapter 4 Standing Tree Remediation Plan 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. THE BECK GROUP Page 23

28 Chapter 4 Standing Tree Remediation Plan FIGURE 6 - SWING BOOM FELLER BUNCHER FIGURE 7 Figure 7 - John Deere Prototype Walking Forest Machine THE BECK GROUP Page 24

29 Chapter 4 Standing Tree Remediation Plan 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 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-tolength 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. THE BECK GROUP Page 25

30 Chapter 4 Standing Tree Remediation Plan 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. THE BECK GROUP Page 26

31 Chapter 4 Standing Tree Remediation Plan 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. Figure 9 Cable Yarding System Merchandising Delimbing 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 10 Processor THE BECK GROUP Page 27

32 Chapter 4 Standing Tree Remediation Plan 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. Figure 11 - Stroke Boom Delimber 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 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 THE BECK GROUP Page 28

33 Chapter 4 Standing Tree Remediation Plan 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 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 stingersteered 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. THE BECK GROUP Page 29

34 Chapter 4 Standing Tree Remediation Plan FIGURE 13 LOG TRUCK 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 OU General Approach 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. THE BECK GROUP Page 30

35 Chapter 4 Standing Tree Remediation Plan 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 BECK GROUP Page 31

36 Chapter 4 Standing Tree Remediation Plan 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 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 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 ) and comply with all requirements under this standard. All personnel will also be fully training in the standard of the SSHP Monitoring 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. THE BECK GROUP Page 32

37 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 Remediation of Northern Europe Forests In 2002 a study 6 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 ( 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 Lynn Hubbard et al. Accessed at: THE BECK GROUP Page 33

38 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 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. THE BECK GROUP Page 34

39 Chapter 5 -- Forest Duff Remediation Plan The results of the test are described in detail in a USFS research bulletin 7 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 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, Colorado 8. 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 Bob Rummer, et al. Document Number MTDC. 8 From Barren to Beautiful at Aspen s Hope Mine. September 10, Accessed at: THE BECK GROUP Page 35

40 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 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 THE BECK GROUP Page 36

41 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 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. THE BECK GROUP Page 37

42 Chapter 6 -- Material Utilization 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 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. THE BECK GROUP Page 38

43 Chapter 6 -- Material Utilization 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 OU Hog Fuel Technologies are proven and available for thermo-chemically destroying asbestos 9. 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 OU 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 THE BECK GROUP Page 39

44 Chapter 6 -- Material Utilization 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. THE BECK GROUP Page 40

45 Chapter 6 -- Material Utilization 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, 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 Loader Operator Debarker Operator Log Clean Up Operator Test Operator Total 6 1 Ensure that safety protocols are in place and being followed 1 Load/unload trucks 1 Operate debarker 1 Operate system for cleaning debarked logs of asbestos fibers 1 Conduct tests to ensure debarked logs, chips, etc. meet asbestos level specifications THE BECK GROUP Page 41