Region 8

Libby: Frequently Asked Questions

Updated February 2014

This section of the Libby website provides responses to questions and concerns of general interest received from the public. This section will be updated regularly to include recent questions and the latest information available. Thank you for your continued interest in the Libby Asbestos Superfund Site.

Please address additional questions to:

Jennifer Lane (lane.jennifer@epa.gov), Community Involvement Coordinator
or
Libby Faulk (faulk.libby@epa.gov), Regional Public Liaison

U.S. Environmental Protection Agency, Region 8
1595 Wynkoop (8OC)
Denver, CO 80202-1129

Click on a question below to see EPA's response.


General Interest Questions

  • Is Libby a safer place to live in or visit now than it was ten years ago?
    Yes. Cleanup at the Libby Asbestos site has been occurring since November 1999. Since then, EPA has made much progress in reducing the amount of asbestos in the Libby area. This has reduced the chance of contact with asbestos, which is known to cause lung disease and other breathing problems. For example, currently the amount of asbestos in air is nearly 10,000 times lower than it was in downtown Libby during the period when the mine and milling plants were in operation. Although there is much less asbestos in Libby than there was 10 years ago, there are still potential health risks because it will never be possible to remove all the asbestos from the Libby area. Therefore, EPA will continue to take an active cleanup approach, inside and outside targeted properties that have Libby Amphibole asbestos. This will continue to reduce the risks of exposure to asbestos.
    • More Information »
      The Libby Asbestos site has been on EPA's Superfund National Priorities List since 2002, and cleanup has taken place since November 1999. EPA has made progress in reducing the threat of asbestos on the ground and in the air and, as a result, has reduced the risk of lung cancer, asbestosis and other respiratory problems. While EPA's cleanup efforts have greatly reduced exposure, past and future exposures of amphibole asbestos may remain a public health concern in the area. It is not feasible to remove all asbestos from the Libby area, but EPA believes that its actions have reduced risks as specified in federal Superfund guidance. While EPA's cleanup efforts have greatly reduced exposure, past and future exposures of amphibole asbestos may remain a public health concern in the area.

      There is much less asbestos contamination in Libby than there was 10 years ago; however there are still potential risks pertaining to exposure to asbestos-contaminated vermiculite. That is why EPA is currently taking a combined approach of "action" (indoor and outdoor cleanups at targeted properties) and "investigations and studies" that support the final remedy decisions for the site.

      The most recent ambient air quality report (2009) summarizes air sampling at 14 stations throughout Libby. The report indicates that Libby Amphibole asbestos (LA) air concentrations are approximately 10,000 times lower than the reported air concentrations in downtown Libby during the period when the mine and milling plants were in operation.
  • What is Libby Amphibole asbestos (LA)?
    "Asbestos" is the name of a group of fibrous minerals. Asbestos fibers do not dissolve or readily disintegrate. Because of its fiber strength and heat resistant properties, asbestos has been used to make numerous products including roofing shingles, ceiling and floor tiles, automobile clutches and brakes.

    There are two general types of asbestos, amphibole and chrysotile. Chrysotile is the commercial asbestos most commonly used around the country. Amphibole asbestos fibers are generally straighter and break apart more easily than chrysotile fibers. The specific type of asbestos in Libby is called Libby Amphibole (LA), which is a mixture of six different asbestos minerals.
    • More Information »
      Asbestos is the name of a group of highly fibrous minerals with separable, long and thin fibers. It is a mineral fiber that has been used commonly in a variety of building construction materials for insulation and as a fire-retardant. Because of its fiber strength and heat resistant properties, asbestos has been used for a wide range of manufactured goods, mostly in building materials (roofing shingles, ceiling and floor tiles, and asbestos cement products), friction products (automobile clutch, brake and transmission parts), heat-resistant fabrics, packaging, gaskets and coatings. The fibers do not dissolve or readily degrade. They can remain airborne for quite some time but eventually settle onto soil, sediment or other materials (e.g. carpet). There are two general types of asbestos, amphibole and chrysotile. Amphibole asbestos fibers are generally straighter and break apart more easily than other asbestos fibers. Please also refer to ABCs of Asbestos.

      The specific type of asbestos in Libby is called Libby Amphibole asbestos (LA). Libby Amphibole asbestos has been recognized to be unique as it is both chemically and structurally different from chrysotile, the commercial asbestos most common around the country. Libby Amphibole asbestos is a mixture of six different identified mineral species. One of the features of amphibole asbestos is the tendency of larger fragments to fracture, forming long, thin, needle-like mineral fibers.
  • How does asbestos make people sick?
    People are more likely to contract asbestos diseases when they are:
    1. exposed to high amounts of asbestos,
    2. exposed to asbestos often, and/or
    3. exposed for long periods.
    Asbestos diseases most often affect those people who work in asbestos mining and milling. However, they may affect people who work with asbestos products as well. Asbestos diseases may affect spouses and children of people who worked with asbestos. In this case, the spouses and children are exposed to the asbestos that was brought home on clothing, shoes or other materials from the work site.

    Asbestos must get into the body to cause an adverse response. When asbestos enters the body, most of the asbestos is expelled. However, some asbestos may become lodged in the lungs. In response to the foreign object, the tissue becomes inflamed and the body begins building scar tissue around the fibers reducing lung function. This results in lung diseases, both non-cancerous and cancerous. Generally, asbestos diseases take a long time to develop—anywhere between 10 to 30 years after exposure to asbestos. Tobacco smoking greatly increases the chance of contracting asbestos diseases.
    • More Information »
      Asbestos must get into the body to cause an adverse response. The main concern is the inhalation of asbestos found in the air. Asbestos can also be ingested, but many more fibers are needed to cause an adverse response from ingestion compared with inhalation. When asbestos enters the body, most of the asbestos is expelled. However, some asbestos may become lodged in the lungs. Scientists are still researching the mechanism for asbestos lung toxicity. The initial response to asbestos fiber in the lung is inflammation coupled to an immune response.

      Asbestos exposure is associated with both non-cancer diseases such as asbestosis and pleural plaques and cancers such as mesothelioma and lung cancer. Asbestos is an illness characterized by the scarring of the lungs which reduces their ability to function. Mesothelioma is an asbestos-related cancer of the membrane lining the chest or abdominal cavity.
      People are more likely to experience asbestos-related disorders when they are exposed to high concentrations of asbestos and are exposed for longer periods of time. These effects are more often found in occupations such as mining, milling, manufacturing, insulating, shipbuilding, construction and others.

      Cases of asbestos-related illnesses have also been associated with people exposed to asbestos indirectly in non-occupational settings. Wives, husbands and children of people who worked with asbestos have contracted asbestos-related illnesses after being exposed to asbestos on the clothes of those workers who were directly exposed.

      Generally, a latency period of 10 to 30 years precedes the expression of an asbestos-related illness. The potential for disease is dependent on other factors in a person's life, including whether a person smokes or smoked in the past. According to research statistics, a smoker who is exposed to asbestos is 50-90 times more likely to develop an asbestos-related illness than a non-smoker. Some scientists believe that one reason for a smoker's susceptibility to asbestos is due to the loss of the lung's capability to rid itself of fibers.

      If you are concerned about possible exposure, talk to your doctor and consider consulting a physician known as a pulmonologist who specializes in lung diseases. For more information on asbestos-related diseases, see the Agency for Toxic Substances & Disease Registry's page on asbestos health effects, their asbestos and health fact sheet, or EPA's page about asbestos-contaminated vermiculite. Information on asbestos-related diseases can also be found at the Center for Asbestos Related Diseases (CARD).
  • Is asbestos naturally occurring in the Libby area?
    Yes. Asbestos is a naturally occurring mineral in the Libby area as well as at other locations around the world. Vermiculite is also naturally occurring in this area. The vermiculite deposits in Libby are contaminated with a naturally occurring asbestos called Libby Amphibole asbestos or LA. EPA is working on a study to understand the natural background levels of LA.
  • What is meant by the term natural "background" levels of Libby asbestos?
    Many substances are found naturally in the environment such as calcium, potassium, copper and asbestos. Both vermiculite and asbestos are found in the Libby area as a function of natural geologic processes. Some of the vermiculite and asbestos found in the Libby area is due to human activities; such as mining and mineral processing that removed these substances from mineral deposits and placed them in surface soils and in homes. Understanding the difference between the vermiculite and asbestos that is in the environment due to natural causes, versus man-made influences, is part of the Remedial Investigation of the Superfund site.
  • Why is the background level of Libby Amphibole important?
    Soil background levels and other data are used by EPA to establish cleanup goals for the site that are protective of human health and the environment. It should be noted that EPA generally does not establish cleanup levels that are below background levels.
  • How did asbestos get deposited throughout the Libby area?
    The vermiculite ore at Libby also contains Libby Amphibole asbestos (LA). While the LA was not mined for commercial purposes, the minerals were mined together. LA fibers are small and are easily transported by air after they are disturbed. The vermiculite mining and milling activities caused the vermiculite, which was contaminated with LA, to spread across the entire area. The LA-contaminated vermiculite was also used in homes as insulation and added to soils to hold moisture and nutrients. Additionally, the LA fibers were unintentionally transported from the mine on clothing, shoes, and in the cars of the mineworkers.
    • More Information »
      Mining, handling and processing of vermiculite led to widespread contamination of the area with mining waste. Asbestos is also found in the Libby area due to naturally-occurring geologic deposits exposed during glacial activity. While amphibole asbestos at Libby was not mined for commercial purposes, mineral deposits were co-located with the vermiculite ore and were mined coincidentally. A large portion of the vermiculite contained a form of naturally-occurring asbestos referred to as Libby Amphibole asbestos (LA). Amphibole fibers are small and are easily transported by air after they are disturbed. They fall onto soil, sediment, trees or areas inside houses. Mining operations disturbed the vermiculite releasing asbestos into the air and it made its way through the area and into the town of Libby. Workers at the mine also carried the asbestos dust home on their clothes and in their vehicles after each day of work at the mine.

      A transfer facility was at the base of the mountain approximately five miles from Libby. Over time, two expansion ("popping") facilities were located inside the Libby city limits; one of these facilities was next to community baseball fields and readily accessible to children. These facilities heated vermiculite to approximately 600 degrees Fahrenheit in order to expand ("pop" or exfoliate) the crystals. Asbestos fibers associated with the vermiculite may have been released into outdoor air during this process. Additionally, vermiculite containing asbestos fibers was commonly used throughout the area as construction aggregate, soil additive in gardens, and insulation in homes. Natural geologic processes may also have resulted in spreading asbestos throughout the area. EPA is conducting studies to evaluate naturally occurring background levels of asbestos in the Libby area.

      More information on the Libby mining operation is available at ATSDR's
      Protocol to Confirm Asbestos-Related Abnormalities.
  • How many properties has EPA remediated at Libby?
    EPA has cleaned up over 1,600 properties in both Libby and Troy. This included removing soil, insulation and debris that contained asbestos. EPA has also conducted cleanup actions at the former mine facilities and schools in Libby. The cleanup activities continue at over 100 properties per year.
    • More Information »
      As of October 2011, EPA, with the support of Montana Department of Environmental Quality, remediated 1,603 commercial and residential properties in Libby and Troy, significantly reducing risks to area families. The agencies removed over 940,000 cubic yards of contaminated soil, 25,323 cubic yards of asbestos-contaminated vermiculite attic insulation and 43,164 cubic yards of asbestos containing debris. EPA also conducted response actions to reduce risks at former processing facilities, school yards and various abandoned waste piles. EPA and MDEQ are removing asbestos from 100 to 200 properties per year.
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    Action Levels and Removal Clearance Criteria

  • Why isn't EPA removing vermiculite from enclosed areas?
    Vermiculite can be found in walls, inaccessible crawl spaces and attics. Unless it is disturbed and released into open, exposed areas, there is no exposure and it poses no current risk. Therefore, it does not need to be removed.
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    Asbestos in Ambient Air in Libby

  • Is the level of Libby Amphibole asbestos (LA) in ambient (outdoor) air decreasing in Libby?
    Yes. The levels of Libby Amphibole (LA) asbestos have been greatly reduced in outdoor air since 1999. Currently the amount of asbestos in air is nearly 10,000 times lower than it was in downtown Libby during the period when the mine and milling plants were in operation.
    • More Information »
      Outdoor air levels of Libby asbestos have been significantly reduced since 1999. The most recent outdoor or ambient air report, Summary of Ambient Air Monitoring for Asbestos at the Libby Asbestos Site, dated February 9, 2009, indicates that LA air concentrations are approximately 10,000 times lower than the reported air concentrations in downtown Libby during the period when the mine and milling plants were in operation.

      As described in the February 2009 ambient air report, EPA collected data on the levels of LA in outdoor ambient air at numerous monitoring locations in and around the community of Libby. LA concentrations in ambient air tend to be very low in winter and higher in the middle to late summer when conditions are usually dry. LA concentrations tend to be somewhat higher in the northern and eastern portion of Libby than in the central and southern regions, although these differences are not statistically significant. Cancer risk estimates computed using the risk model currently recommended by EPA are within EPA's current acceptable risk ranges. This indicates that inhalation of LA in outdoor ambient air in and around the community of Libby is unlikely to be a source of significant cancer risk to those living in or visiting Libby area.

      The table below shows the overall improvement in Libby ambient air concentrations of LA.
      Date of Sampling Location Asbestos in Ambient Air Concentrations (s/cc)
      Pre-1990 City center 0.59
      2002 Lincoln County Courthouse Annex 0.00010 to 0.00086
      2008 Average community-wide ambient air monitors 0.0000056

      s/cc = structures (Libby amphibole asbestos fibers) per cubic centimeter
      Values for the pre-1990 data came from:
      Harry Eschenbach Deposition Exhibit 182.126. Nelson, Ryan & Albert vs. W.R.Grace. Airborne fiber concentrations in downtown Libby. W.R. Grace Company. 62 Whitmore Ave., Cambridge, MA. (page 21)
      MRI (1982) "Collection, Analysis and Characterization of Vermiculite Samples for Fiber Content and Asbestos Contamination" Final Report . Washington, DC. U.S. EPA Contract No. 68-01-5915. (page 28)
      As a basis for comparison, ambient air samples were also collected at a sampling location in Helena, Montana in 2006, 2007 and 2008. In 2007, the results from these samples in Helena showed mean asbestos concentration levels of 0.000019 s/cc with maximum levels of 0.000215 s/cc. In 2008, mean asbestos concentration levels detected at the Helena station were 0.000009s/cc with a maximum level of 0.000119 s/cc. These results are shown in the February 2009 ambient air monitoring report.

      Libby asbestos data related to decision-making are available to the public in final study reports that are posted on the site website at Libby Site Documents.
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    Communication and Public Involvement

  • Does EPA involve Libby citizens in the cleanup process?
    Yes. The Libby site team is committed to involving the Libby community in the cleanup process. The site team understands that community engagement must be flexible and open. Suggestions from the community on how to improve involvement with citizens are always welcome. Meetings with local groups are held monthly. The site team also holds quarterly community meetings, which focus on current topics and activities. Citizens are encouraged to drop by the EPA Information center at 108 East 9th Street in Libby to talk with the EPA onsite project manager.
    • More Information »
      Yes. The Superfund community involvement effort in Libby is extensive. The site team understands that community engagement must be flexible and tailored to Libby's specific information and involvement needs. The team welcomes suggestions of additional ways to meet the community's desire to be engaged in the Superfund project in Libby.

      EPA and the Montana Department of Environmental Quality are committed to involving the Libby community in the cleanup at the site. Most critical site documents are posted on the Libby website and are available for review at
      the EPA Information Center in Libby (406-293-6194).

      EPA provides numerous opportunities for two-way communication and community involvement in the decision-making process. Members of EPA staff meet monthly with a wide range of stakeholders including the Libby City Council, Lincoln County Commissioners, Community Advisory Group, Chamber of Commerce, Congressional staff, Technical Assistance Grant recipient, City/County Health Board, Healthy Communities Initiative and Operations and Maintenance Work Group. The site team schedules quarterly community meetings focusing on current topics. Citizens also may drop by
      the EPA Information Center at 108 East 9th Street in Libby to talk with the EPA onsite project manager.
       
  • What are some opportunities for community involvement in Libby?
    By law, EPA must make sure opportunities for community involvement are available. Therefore, EPA uses a variety of tools to keep the local community informed about issues and the cleanup progress. EPA supports open communication with the community. Regular public meetings are held with citizens and citizen groups. Ads and columns are published in the local newspapers. Fact sheets and public service announcements are distributed. Citizens are encouraged to drop by the EPA Information Center located at 108 East 9th Street in Libby. The staff provides one-on-one contact for any community member to discuss their concerns. Citizens may also call the Information Center (406-293-6194).
    • More Information »
      The Comprehensive Environmental Response, Compensation, and Liability Act (CERLCA, or the Superfund law) incorporates community involvement into the Superfund process. The intent of the law is to ensure appropriate opportunities for public involvement in site-related decisions, including site wide analysis and characterization, remedial alternative analysis, and selection of remedy. EPA is required to conduct community interviews and appropriate activities to ensure public involvement. Because of the unusual situation at Libby, EPA has provided additional opportunities for people to become involved in the agency's activities and to help shape the decisions that are made.

      At Libby, EPA has used a variety of tools to keep community members informed about issues and progress at the Libby site and to encourage two-way communication. EPA holds public meetings and availability sessions, publishes display ads and columns in the local newspapers, develops and distributes fact sheets and publishes public service announcements when there is new information to share or events taking place.

      EPA maintains a centrally located storefront Information Center in Libby at 108 East 9th Street that is staffed by an office manager and a full-time EPA onsite project manager. The Information Center provides easy access to the community on information about cleanup activities and provides one-on-one contact for any community member concerns. EPA houses a local information repository in the Information Center (406-293-6194) as well as at
      the EPA regional headquarters in Denver (800-227-8917 for those located within the Region 8 states, or 303-312-6312).
  • How Is EPA contributing to economic redevelopment efforts in Libby?
    EPA’s primary goal is to protect human health and the environment. However, EPA has participated in a number of redevelopment projects. One of which is the Kootenai Business Park. EPA worked closely with local agencies to expedite the cleanup of the area so that local businesses could begin using the property. Also, the Libby site team joined forces with the city to produce several economic development workshops. The workshops provided information about local properties and the cleanup work. This assisted in bringing new businesses to Libby. Other workshops have provided networking opportunities for the community. Additionally, EPA’s contractor trains and employs Libby residents in the site cleanup.
    • More Information »
      While EPA's primary mission is to protect human health and the environment, EPA has participated in economic redevelopment projects when possible. For example, EPA worked closely with local agencies to expedite cleanup of a portion of the Kootenai Business Park to allow businesses such as Stinger Welding to locate a new facility on the property.

      The Libby site team collaborated with the city on a number of economic development projects including producing several economic development workshops and facilitating bringing new businesses to Libby by providing information about specific properties and expediting cleanup work on those properties. EPA's contractor trains and employs Libby residents in the site cleanup.

      In addition, EPA conducted two community-wide Redevelopment Workshops featuring speakers from multiple agencies and locations. These workshops provided networking opportunities and facilitated discussions on economic and redevelopment opportunities for the community.
  • Does EPA incorporate public input into decisions?
    Yes. EPA seeks public input into decisions regarding cleanup activities at Libby. While EPA cannot always comply with each request, EPA does incorporate public input into its decisions whenever possible. Opportunities for public input include interviews with Libby residents, citizen groups, and local officials. It also includes regularly scheduled meetings with various citizen groups, city council, and county commissioners. The public is asked to provide comments on key documents. EPA funded a local citizen group, so they could provide technical review of data and documents, and input into decisions. An example of responding to public requests is the cleanup of the golf course. This was done at an earlier date than originally planned. Additionally, EPA is incorporating the city’s plans for the cleanup and restoration of Riverfront Park.
    • More Information »
      EPA seeks and incorporates public input into its decisions. Opportunities for public input include interviews with community residents, public interest groups and local officials; meetings with businesses, property owners, and the real estate community; Community Advisory Group and Technical Advisory Group meetings; workshops, public meetings and availability sessions; and city council and county commissioners meetings. EPA formally invited public comments on key documents such as the proposed plans for Operable Units (OUs) 1 and 2 and funded a Technical Assistance Grant to allow a local group to provide technical review of data and documents and input into decisions.

      While the Agency cannot always do what each stakeholder requests, EPA incorporates public input into its decisions whenever it is possible to do so. There are several instances where public concerns modified EPA's activities. For example, in response to concerns expressed during the public comment period on the OUs 1 and 2 proposed plans about issuing a cleanup decision before a final risk assessment, EPA committed to perform a quantitative risk assessment following completion of the remedial action at OUs 1 and 2. This risk assessment will include ABS sampling and new Libby-Amphibole-specific toxicity factors that will be available by that time. Other examples of responding to public requests include remediating the golf course at an earlier date than initially planned and consulting with advocacy groups when working on creek banks. Currently, the agency is incorporating the city's plans for Riverfront Park in the OU1 remedial design.
  • Does EPA respond to questions and requests for information from Libby citizens?
    Yes. EPA is committed to answer questions and requests for information from the public. EPA has an Information Center located at 108 East 9th Street in Libby. EPA’s Libby Asbestos website provides documents and lists contacts for requesting information. The website also provides site-related information, site history, technical information, reports, and links to other agencies and related sites.

    Citizens may also send written questions to the following contacts at EPA‘s Denver office:
    Libby Faulk (faulk.libby@epa.gov)

    Regional Public Liaison
    U.S. Environmental Protection Agency, Region 8
    1595 Wynkoop Street (8OC)
    Denver, CO 80202-1129

    Another way to request information about the Libby site is by submitting a Freedom of Information Act (FOIA) request.
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    Former Export and Screening Plants

  • What is the current status of the former export plant (Operable Unit or OU1) and when will it be cleaned?
    EPA conducted a remedial investigation at Riverfront Park (the former export plant/Operable Unit 1). Based on the results, EPA completed a number of removal actions at the park. In 2010, EPA worked with the city to complete the remedial plan, which included the city’s plans for Riverfront Park. Remediation of the park began in the spring of 2011. These activities will be completed in 2012. EPA will perform a post-cleanup risk assessment to confirm the effectiveness of the remedy.
    • More Information »
      In the Remedial Investigation for Operable Unit 1, EPA identified the site of the former export plant as a location where park workers may be at risk from exposure to asbestos. Based on this Remedial Investigation, in May 2010, EPA and the Montana Department of Environmental Quality selected a remedy. EPA began implementing the remedy in the spring of 2011.

      EPA has taken a number of removal actions to reduce the potential for public contact with visible vermiculite at Riverfront Park (the former export plant location). The parking area was expanded so people can park in a place where the potential for exposure has been reduced by capping visible vermiculite. As an interim measure to reduce the likelihood of exposure until the OU1 remedial plan is initiated, EPA placed six inches of clean fill over areas of visible vermiculite in OU1. Barrier fencing was installed to delineate areas of visible vermiculite and signs were placed on the fencing to further inform park users to avoid the fenced area. This fencing also limits the potential for cross contamination between areas of the site where cleanup was conducted and those areas of the site where residual asbestos contamination may remain in surface soil.

      During 2010, EPA worked with the city of Libby to incorporate its plans for Riverfront Park. Comprehensive remediation of Riverfront Park started in the spring of 2011 after an agreement with the city was completed. Construction is scheduled to be completed in 2012. EPA will conduct a post-construction risk assessment, including activity-based sampling (ABS), following the establishment of a vegetative cover. The remedy will also be evaluated when new Libby Amphibole (LA) toxicity values are available to confirm the effectiveness of the remedy.

      For more information on the remedial plan, please see the Operable Unit 1 Record of Decision and response to comments.
  • Are there risks to concert goers and casual users of Riverfront Park?
    Measures have been taken to minimize exposures to casual park users. Cleanup of Riverfront Park began in the spring of 2011 and is planned to be completed in 2012. Once completed, the risk to concert goers and casual users will be minimized. EPA will conduct a post-construction risk assessment after the vegetative cover is established.
    • More Information »
      The city allows casual uses of the park, such as family gatherings, weddings and concerts. Measures have been taken to minimize exposures to casual park users. The cleanup work that began in 2011 and is expected to be completed in 2012 has reduced risks of exposure to casual park users. EPA will conduct a post-construction risk assessment when new toxicity values are available to confirm the effectiveness of the remedy.
  • Were buildings demolished at the former export plant property (Operable Unit 1)?
    Yes. The structures were part of the historic mine operations and were demolished in September/October 2001 by W.R. Grace. The buildings were in poor condition, did not meet current building codes and could not be decontaminated. The asbestos-contaminated building materials and soils were disposed of at the former mine site. Excavations were backfilled with fill material, and gravel or topsoil was then placed on top of the backfill material. EPA provided oversight of the work to ensure the activities complied with federal and state requirements.
    • More Information »
      EPA issued a Unilateral Administrative Order (UAO) to W.R. Grace on May 23, 2000, based on the finding of Libby Amphibole asbestos (LA) at levels of concern in air and site soil at the former export plant property. The UAO required that W.R. Grace temporarily relocate the onsite business (Millwork West), clean five onsite historic buildings belonging to the city of Libby and the building's contents, excavate and dispose of vermiculite and LA-contaminated soil and debris, and restore the property. The structures were ultimately demolished because they were in poor condition, did not meet current building code requirements, and could not be decontaminated. In exchange for the value of the city-owned buildings, and at no cost to the city, W.R. Grace built a water main to the property that meets all code requirements. Grace also temporarily relocated Millwork West, which decided not to move back to the property. EPA provided oversight of W.R. Grace's work to ensure compliance. Contaminated materials were disposed of at the former mine. The excavation was backfilled with EPA-approved fill, and the final 6-inch layer was either gravel or topsoil, depending upon original surface conditions.
  • What is the current status of Operable Unit 2 (former screening plant) and when will it be cleaned?
    EPA completed a remedial investigation at the former screening plant location (Operable Unit 2). Based on the results, EPA completed a number of response actions at the property. The response actions included removal of vermiculite, dust, soil and asbestos. In 2010, two areas were cleaned up at the 19-acre Flyway area, which is a large portion of Operable Unit 2. Libby Amphibole asbestos (LA) is still present in subsurface soils across the area. EPA is currently developing methods for managing the subsurface soil with LA.
    • More Information »
      Operable Unit 2 (OU2), the former screening plant includes four areas including the 21-acre former screening plant; the 19-acre flyway; a 1-acre private property; and the Rainey Creek Road Frontage. OU2 is mostly undeveloped and contains only two buildings.

      This operable unit has undergone extensive investigation and response actions. Response actions at Operable Unit 2 occurred from 2000-2006 and included removal of vermiculite, dust, soil and asbestos. The Remedial Investigation Report published in August 2009 described that most surface soils in OU2 have been remediated. Two locations in the Flyway were remediated in 2010. LA remains in subsurface soil across OU2. EPA is in the process of developing institutional controls to manage subsurface contamination.
  • When can the former screening plant be used for commercial development (Operable Unit 2)?
    EPA finished a number of response actions at the property. Libby Amphibole asbestos (LA) is still present in subsurface soils. EPA is working on methods for managing the subsurface soil with LA. The Environmental Resource Specialist program is available to help manage contaminated soils. ERS can be contacted at 406-291-5335.
    • More Information »
      The former screening plant property is available for redevelopment. There is asbestos contaminated soil left in place at depth. To the extent that development encounters the contamination, the Environmental Resource Specialist program is available to assist the developer in properly managing this contamination. The Environmental Resource Specialist can be reached at 406-291-5335.
  • What is the process for reopening the Record of Decision (ROD)?
    A Record of Decision (ROD) is a legal document that presents the selected remedy at a site. It also provides the rationale used to arrive at the selected remedy. Asbestos-containing soil has been covered at Operable Units (OUs) 1 and 2 in order to prevent human exposure to the soil. Because the soil was not removed to allow unrestricted use of the property, a review of the selected actions for these OUs is performed no less than every five years by EPA. This assures that the selected remedies continue to protect human health and the environment. If it is determined that an action is no longer protective, the ROD may be amended to require additional actions.
    • More Information »
      If, at any time, it is determined that a remedy is no longer protective, the ROD may be amended to require additional protective actions. Because the selected remedies for Operable Units 1 and 2 result in contaminants remaining on site (under engineered covers) above levels that allow for unlimited use and unrestricted exposure, a statutory five-year review must be conducted pursuant to the Superfund law. EPA will conduct a review of remedial actions no less often than every five years after the initiation of a remedial action to assure that the remedy continues to be protective of human health and the environment. These five-year reviews include any additional information related to human health or ecological risk that is developed during the period covered by the review.

      EPA will conduct a quantitative risk assessment, including activity-based sampling, at the location of the former export plant after construction is complete and toxicity values are available to confirm effectiveness of the remedy. If unacceptable exposures are identified, EPA will take action as necessary to ensure protectiveness. Actions may include additional excavation, improving covers and/or strengthening land use controls and other institutional controls.
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    Grace Settlement Funds

  • Is the recent Grace settlement funding the cleanup at Libby?
    Yes. Money from the 2008 W.R. Grace settlement has been used to fund the cleanup of the site. $250 million were received in the settlement agreement. The money was placed in special EPA, interest bearing accounts. The settlement agreement requires EPA to use the $250 million on the cleanup projects, investigations, and operations and maintenance. The state also has a separate settlement agreement with W.R. Grace to provide funds for state operations and maintenance expenses.
    • More Information »
      Since the civil settlement with W.R. Grace in 2008, EPA has been funding the cleanup at the Libby Asbestos site with money from the settlement. The settlement action settled a bankruptcy claim brought by the federal government to recover money for past and future costs of cleanup in Libby. The settlement agreement requires EPA to spend the $250 million received on cleanup projects, site-specific investigations, and operations and maintenance.

      The $250 million received from the settlement with W.R. Grace was placed in special EPA interest bearing accounts used for the Libby site. One account was set up with $239 million of the settlement funds, which are being used to pay for Libby project costs. The remaining $11 million of the settlement funds were placed into a separate interest-bearing account that will be used to help the state of Montana pay for future operation and maintenance. The state also has a separate settlement agreement with W.R. Grace to provide funds for state operation and maintenance expenses.
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    Human Health Risk Assessment

  • What is a human health risk assessment?
    Superfund risk assessments are conducted to evaluate the potential human health and ecological risks from the uncontrolled release of hazardous substances. They are conducted in a step-by-step process that estimates current and future health risks to the public and the environment. Risk assessments use standardized tools, formats and processes and are conducted by experienced professionals. Data collected at a site are used to estimate human exposure to the contaminants. Using toxicity data for the contaminants, risks to human health are estimated. A similar process is used to estimate risks to the environment. The results of the risk assessments are used for determining the steps for managing the contamination.
  • What a Risk Assessment Is and Is Not
    A risk assessment is an evaluation of the potential human health risks posed by exposure to hazardous substances. At Libby, the hazardous substance is Libby Amphibole asbestos (LA). It is not an evaluation or study of health conditions a person already has or a medical examination. It does not identify ways a person may have been exposed to LA in the past, nor does it identify if existing health problems were caused by exposure to LA in the past.

    A Risk Assessment IS:
    • A comprehensive study of the pathways through which people might come in contact with Libby Amphibole asbestos (LA). (Inhalation or breathing is the pathway of concern in Libby.)
    • A calculation of how likely it is that human health effects might occur in current/future residents because of the LA in a specific area. A tool to assist EPA in making cleanup decisions.

    A Risk Assessment IS NOT:
    • A study of health conditions you may already have.
    • A medical examination.
    • A re-creation or comparison of ways you might have been exposed to contaminants in the past to current environmental exposures.
    • A study that will tell you directly if any existing health problems you have now were caused by any contact you may have had with Libby Amphibole in the past.
  • What are some common terms used in risk assessments?
    Reference Dose (RfD) is an estimated daily dose of a contaminant to a population that is not likely to cause non-cancer effects during a lifetime of exposure.

    Inhalation Reference Concentration (RfCs) is a concentration of a contaminant in air that is estimated to not likely cause non-cancer effects during a lifetime of exposure.

    Inhalation Unit Risk is the estimated lifetime cancer risk from continuous exposure to a contaminant in the air.

    Naturally occurring refers to something that exists in nature that is not a result of human activity.

    Background levels are the naturally occurring levels of any material found in the environment. These levels are not associated with human activity.

    Variability refers to the range of toxic response in a population, or the range of exposure to a contaminant. For example, the dose that might cause a toxic response can vary from one person to the next depending genetics, age, health, etc. Exposure to a contaminant may vary from one person to the next depending on where one works, time spent indoors or out, where one lives, how much people eat or drink, etc.

    Uncertainty in risk assessment refers to our inability to know for sure. This is often due to having incomplete data or simply due to the variability in a measurement. For example, uncertainty arises when estimating health effects on humans based on health effects on animals. It can also arise when estimating health effects on children based on health effects in an adult.

    Peer review is a critical review of a document or procedure. This is conducted by independent experts who are knowledgeable in the field of question.
    • More Information »
      Reference Dose (RfD) is an estimate of the daily lifetime dose of a substance to a population (including sensitive subgroups) that is unlikely to cause harm. An RfD is generally used in EPA's non-cancer health assessments for oral (ingestion) exposures.

      Inhalation Reference Concentrations (RfCs) are critical components of the agency's risk assessments. RfCs are used to help estimate non-cancer health effects from inhalation exposures. RfCs are an estimate of a continuous inhalation exposure concentration to people (including sensitive subgroups) that is likely to be without risk of harmful effects during a lifetime.

      Until recently, there have been no non-cancer toxicity values for any form of asbestos that can be used to quantitatively assess risk from exposure. EPA is sponsoring research to develop Libby Amphibole-specific toxicity values and to better understand the health effects of amphibole asbestos exposure.

      Inhalation Unit Risk (IUR) is used to assess inhalation cancer risks. It is the lifetime cancer risk estimated to result from continuous exposure to a contaminant in air. It will address both lung and mesothelioma as endpoints.
      Naturally occurring. Something that is natural to the area in which it is found and unaltered by human activity. Asbestos is a naturally occurring mineral in the Libby area, and also is found in other locations around the world. Vermiculite is also naturally occurring in this area.
      Background levels. EPA refers to "background" as the level of Libby Amphibole that occurs naturally in Libby area soil and not as a result any current or past human-related activities. It is standard practice for EPA to determine background levels of constituents when evaluating Superfund sites. EPA is currently conducting a study to determine the natural background level of LA. This information will also be public information.
      Quantifying soil background levels in the Libby area will help inform risk management decisions for the site. EPA will establish cleanup goals for the site that are protective of human health and the environment; however, EPA generally does not establish cleanup levels that are below background levels.
      Variability refers to the range of toxic response in a population or exposure. For example, the dose that might cause a toxic response can vary from one person to the next depending on values such as genetic differences, age, preexisting medical conditions, etc. Exposure may vary from one person to the next depending on values such as where one works, time spent indoors or out, where one lives, how much people eat or drink, etc.
      Uncertainty in risk assessment refers to our inability to know for sure—it is often due to incomplete data or the variability in a measurement. For example, when assessing the potential for risks to people, toxicology studies generally involve dosing of mature test animals such as rats as a surrogate for humans. Since we don't always know how differently humans and rats respond, EPA often employs the use of an uncertainty factor to account for possible differences. Additional consideration may also be made, for example, if there is some reason to believe that the very young are more susceptible than adults, or if key toxicology studies are not available.
      Peer review is a documented critical review of a scientific/technical work product which is conducted by scientific experts knowledgeable in the field of question who are independent of those who performed the work. Peer review can provide an independent evaluation of the assumptions, calculations, extrapolations, alternate interpretations, methodology, acceptance criteria and conclusions pertaining to the scientific/technical work product.
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    Kootenai Business Park (Operable Unit 5, former Stimson complex)

  • What is known about the wood chip material at the Kootenai Business Park Industrial District?
    Wood chips from the former Stimson Lumber Mill have been sold as landscaping material in Libby and other areas. Members of the community raised concerns that the wood chips may pose a potential asbestos exposure risk to the residents. Therefore, EPA collected samples of the wood chips. The results showed that Libby Amphibole asbestos (LA) was present in a limited number of samples. EPA also collected activity-based samples, which are air samples collected while the materials were disturbed to see how much, if any, LA was released into the air. No LA was detected in any of the air samples. Additional wood chip samples were collected in 2011 along with activity-based samples. While low concentrations of fibers were detected in the wood chips, all activity-based samples were non-detect for LA. There are no known exposures to LA from the wood chips. EPA plans no further action for the wood chips at the Kootenai Business Park Industrial District.
    • More Information »
      Wood chips from the former Stimson Lumber Mill site in the Kootenai Business Park Industrial District (a portion of Operable Unit 5 of the Libby Asbestos site) have been sold and distributed as landscaping materials in Libby, Montana and elsewhere. Some in the community have raised concerns that the wood chips may pose a potential exposure risk to area residents.

      In October 2007,
      EPA collected bulk samples of the wood chips as part of the Remedial Investigation of OU5. EPA received final sample results in July 2008. The results showed the presence of Libby Amphibole asbestos (LA) in a limited number of the samples. EPA also collected activity-based samples (air sampled during actual disturbance of the materials), which showed no detections of LA during the activities performed. The final sample results were placed on file at EPA’s Information Center in 2008.

      EPA shared the sample results with the Kootenai River Development Council (KRDC) in August 2009. In March 2011, EPA also offered to help KRDC analyze asbestos in the wood chips. In the meantime, EPA recommended that KRDC treat the wood chips as a potentially regulated material. In April 2011, EPA further recommended that KRDC cease sale and distribution of the materials pending further analysis by EPA. Additional wood chip samples were collected in 2011 along with activity-based samples. While low concentrations of fibers were detected in the wood chips, all activity-based samples were non-detect for LA. There are no known exposures to LA from the wood chips. EPA plans no further action for the wood chips at the Kootenai Business Park Industrial District.
  • What can I do if I have landscaping material from the Stimson site in my yard?
    If you have wood chips from the Stimson site in your yard, please call EPA’s Libby Information Center (406-293-6194). EPA personnel will be happy to assist you with what steps to take.
  • Why has it taken so long for EPA to fully assess the risk posed by the wood piles?
    Unfortunately, there are a number of potential sources of asbestos exposure in Libby. EPA must prioritize its activities and address the worst sources first. Initial results from samples of the wood chips and the air did not indicate that this was a significant source for asbestos exposure. Additional wood chip samples were collected in 2011 along with activity-based samples. While low concentrations of fibers were detected in the wood chips, all activity-based samples were non-detect for Libby Amphibole asbestos (LA). There are no known exposures to LA from the wood chips.
    • More Information »
      Unfortunately, the Libby Asbestos site contains many potential sources of asbestos contamination. EPA must prioritize our response activities to address the worst sources and highest exposures first. Initial sampling results and historical information did not indicate that the wood chip piles constituted a major source of asbestos. Further, the activity-based sampling indicated that the wood chips stored in OU5 did not result in asbestos exposure for individuals working on and around them. Additional wood chip samples were collected in 2011 along with activity-based samples. While low concentrations of fibers were detected in the wood chips, all activity-based samples were non-detect for LA. There are no known exposures to Libby Amphibole asbestos (LA) from the wood chips.
  • What action is EPA taking now?
    EPA recommended that the wood chips no longer be sold as landscaping material until further testing was done. In 2011, EPA reanalyzed a portion of the wood chip samples collected in 2007. Additionally, air samples were collected while the materials were disturbed to see how much, if any, asbestos was released into the air. This sampling is referred to as activity-based sampling. While low concentrations of fibers were detected in the wood chips, all activity-based sampling results were non-detect for Libby Amphibole asbestos (LA) associated with the wood chips. EPA plans no further action for the wood chips at the Kootenai Business Park Industrial District. EPA will keep the residents of Libby informed about this issue by writing newspaper articles, holding public meetings, and on this website.
    • More Information »
      EPA asked Kootenai River Development Council to stop the sale of the wood chips while EPA collected data to further evaluate their contents. The agency has further assessed the level of asbestos in the wood chip materials. In 2011, EPA reanalyzed a portion of the bulk samples taken from the site in 2007 and conducted activity-based sampling on the material as well. While low concentrations of fibers were detected in the wood chips, all activity-based sampling results were non-detect for Libby Amphibole asbestos (LA) associated with the wood chips. EPA plans no further action for the wood chips at the Kootenai Business Park Industrial District.

      Finally, EPA is committed to keeping the residents of Libby informed about this issue through newspaper articles, public meetings, and on this website. A fact sheet about the wood chip material at OU5 is available at Residential Landscaping Products from the Stimson Mill Site (OU5). The 2011 sampling results are also provided at
      Summary of Wood-Chip Activity-Based Sampling at the former Stimson Mill site.
  • What is the status of the 400-acre site at Kootenai Business Park?
    EPA completed a remedial investigation at the Kootenai Business Park. A number of response actions and sampling events have also been completed. The response actions included removing insulation and soil. A number of locations also had asbestos materials and debris, which were removed. EPA will evaluate actions to address contamination after the risk assessment is done.
  • Will there be opportunities for redevelopment in the Stimson complex?
    Yes. EPA hopes that portions of the Stimson complex can be redeveloped. Environmental investigations completed at the property indicated that portions of the site have not been impacted by asbestos. In 2009, EPA worked with numerous parties to expedite cleanup of a portion of the Stimson complex. This allowed new businesses to locate and use the property.
    • More Information »
      Yes. EPA hopes that portions of Operable Unit (OU) 5 can be redeveloped and contribute to the economic vitality of the community. Based on environmental characterization investigations completed to date, it appears that some portions of the site have not been impacted by asbestos. In other areas of the site, EPA has identified both visible vermiculite and varying concentrations of asbestos in soil.

      In 2009, EPA participated with multiple federal, state and local efforts and the private sector to expedite remediation at a portion of the Stimson complex to allow businesses to locate in this complex. The Stinger Welding facility is the first major tenant in the Kootenai Business Park. More information on the development of this property can be found at
      Fast-Tracked Opportunity at the Stimson Lumber Mill Site (Libby, Montana).
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    Libby Amphibole (LA)-Specific Toxicity Values

  • Why did EPA develop LA-specific toxicity values?
    There were existing cancer toxicity values for asbestos. The values were established based on health effects studies. The studies focused on common types of asbestos including chrysotile, tremolite, amosite and crocidolite. However none of the values were specific to exposures and health effects related to Libby Amphibole asbestos (LA). Additionally, non-cancer values had not been established for any type of asbestos. Therefore, EPA promised the community that it would develop toxicity values specific to LA.

    EPA has now released final toxicity values specific to Libby asbestos for both cancer or non-cancer effects.
  • What are toxicity values?
    A toxicity value is the number that estimates the potential for harm from exposure to a substance.
    • More Information »
      EPA toxicologists have worked over the past years to develop toxicity values for LA including the following:
      Inhalation Unit Risk (IUR) value that quantifies the exposure-response relationship for cancer from breathing concentrations of Libby Amphibole asbestos in the air.
      Reference Concentration (RfC) value that estimates non-cancer harm that people might experience from breathing concentrations of Libby Amphibole asbestos in the air.
      The data used to develop LA-specific toxicity values were obtained from Libby miners and others that were exposed to LA at work, including those at the Marysville, Ohio plant, one of the plants that processed Libby vermiculite.
  • What is IRIS?
    IRIS stands for Integrated Risk Information System. IRIS is a human health assessment database. The database provides data and toxicity estimates for a variety of substances. It was initially developed for EPA staff to provide consistent risk information.
  • What is a toxicity assessment?
    The toxicity assessment evaluates information from various substances at the site. The assessment estimates the potential for harm from exposure to each substance.
    • More Information »
      The toxicity assessment is a key part of the human health risk assessment that determines the relationship between the dose of Libby amphibole and its biological response—for both cancer and non-cancer effects. It is used to estimate the toxicity values for the risk assessment. A toxicity value is the number that relates human health risk exposure to a contaminant.
  • What reviews of the draft Libby Amphibole (LA) toxicity assessment will take place?
    The draft toxicity values were reviewed internally by EPA in the spring of 2011. These values were then reviewed by other federal agencies. After review by the federal government, a public comment period was held from August 25 to October 24, 2011to allow the public to comment on the draft values. Following the public review, EPA released the draft toxicity assessment and toxicity values for peer review by EPA’s Science Advisory Board (SAB). Finally, the SAB will review the values along with the public comments. The board will provide recommendations to EPA. EPA will consider all comments received and the toxicity values may be revised accordingly.
  • What is the draft cancer Inhalation Unit Rate (IUR) for LA and what impact might it have on EPA's assessment of risk in Libby?
    The Inhalation Unit Rate (IUR) relates estimated lifetime cancer risk to a constant exposure to the contaminant in air. The draft IUR for Libby Amphibole asbestos (LA) is 0.17 (fibers/cubic centimeter)-1 [(f/cc)-1]. The current IRIS value for asbestos generally is 0.23 (f/cc)-1.
    • More Information »
      The Inhalation Unit Rate (IUR) provides an estimate of the exposure-response relationship for cancer from breathing LA in the air. Asbestos-related cancers include lung cancer and mesothelioma, an incurable, fatal cancer of the chest cavity. The draft IUR for LA is 0.17 (f/cc)-1 [(fibers/cubic centimeter)-1]. The current IRIS value for asbestos generally is 0.23 (f/cc)-1.
  • How is the draft cancer Inhalation Unit Rate for LA different from the current IRIS value for asbestos?
    Originally, it appeared that Libby Amphibole asbestos (LA) may pose a greater cancer risk than other forms of asbestos. The current draft Inhalation Unit Rate (IUR) for LA is very similar to the existing IUR in IRIS for asbestos. Both values are within the same order of magnitude.
    • More Information »
      The draft cancer IUR for LA is similar within an order of magnitude (a factor of 10) to the current IRIS value for asbestos. When EPA first came to Libby, it appeared as if LA might pose a much greater cancer risk than other forms of asbestos. However, the science does not bear this out.

      The many sources of exposure in Libby appear to account for the incidence of cancer in the community. EPA will use ABS data in an exposure assessment along with the draft IUR to preliminarily estimate cancer risks for Libby residents.
  • What does the draft preliminary cancer Inhalation Unit Rate, coupled with the Libby exposure information, mean for Libby?
    The preliminary results of the risk assessment confirm what EPA has said concerning exposure to asbestos in air. Concentrations of Libby Amphibole asbestos (LA) in the air do not result in risk above EPA’s targets. However, activities that increase the release of LA into the air may result in increased LA exposure and risk. For this reason, EPA recommends that residents do their best to reduce dust whenever possible. For example, residents should water yards before activities such as mowing or digging.
  • How can the cancer risk in Libby be no more than the IRIS cancer risk value when there are so many who have died of lung cancer and mesothelioma in Libby?
    In the past, the exposure to asbestos in Libby was much greater due to the mining and processing of vermiculite. The widespread use of vermiculite at properties throughout Libby also added to the exposure. The higher amount of exposure likely resulted in a higher incidence of cancer.
  • What is the draft non-cancer Reference Concentration (RfC), and when coupled with the cumulative exposure assessment what does it mean for Libby?
    The Reference Concentration (RfC) is the amount of a contaminant in air that is estimated to not likely cause non-cancer effects during a lifetime. For Libby, the greatest concern is exposure to asbestos through inhalation. The preliminary results of the risk assessment confirm what EPA has said concerning exposure to asbestos in ambient air. Concentrations of Libby Amphibole asbestos (LA) in the air do not result in risk above EPA targets. However, activities that increase the release of LA into the air may result in increased exposure risk. For this reason, EPA recommends that residents do their best to reduce dust whenever possible. For example, residents should water yards before activities such as mowing or digging.
    • More Information »
      The Reference Concentration (RfC) provides an estimate of the LA air concentration that is likely to be without appreciable risk of non-cancer harm. The non-cancer harm includes abnormalities of the lining of the lung such as localized pleural thickening and asbestosis. The draft RfC for LA is 0.00001 f/cc (fibers/cubic centimeter). RfCs are used to calculate a hazard index.

      The preliminary results of the risk assessment confirm what EPA has said concerning exposures in Libby. Ambient air concentrations of asbestos do not appear to result in risk above EPA's targets. However, activities that increase the release of soil contaminated with asbestos into the air may result in excessive risk. For this reason, EPA has consistently recommended that residents reduce exposure to dust. For example, residents should water yards before activities such as mowing or digging.
  • How will EPA use the draft toxicity values?
    The draft toxicity values will be used during development of a human health risk assessment. The risk assessment will evaluate the potential health risks from exposure to Libby Amphibole asbestos (LA). The evaluation looks at possible exposure during a variety of activities. These activities include housework, yard work, playing in the yard or at school, walking, bicycling and working outside.
  • What do the draft preliminary human health risk estimates indicate?
    The preliminary results of the risk assessment confirm what EPA has said concerning exposure to asbestos in air. Concentrations of Libby Amphibole asbestos (LA) in the ambient air do not exceed EPA risk targets. However, activities that increase the release LA into the air may result in increased LA exposure and risk. For this reason, EPA recommends that residents do their best to reduce dust whenever possible. For example, residents should water yards before activities such as mowing or digging.
    • More Information »
      The preliminary results of the risk assessment confirm what EPA has said concerning exposures in Libby. Ambient air concentrations of asbestos do not result in risk above EPA's targets. However, activities that increase the release of soil contaminated with asbestos into the air may result in excessive risk. For this reason, EPA has consistently recommended reducing exposure by watering yards before activities such as mowing or digging.
  • What is EPA going to do in Libby based on the toxicity values and exposure assessment?
    EPA will conduct a human health risk assessment. The risk assessment will evaluate the potential health risks from exposure to Libby Amphibole asbestos (LA). The evaluation looks at possible exposure from a variety of daily activities. Data from the risk assessment will be used, in part, to make cleanup decisions for Libby. Other factors EPA considers in selecting a remedy include ability to protect the public in the long term, difficulty of implementing it, costs and community acceptance. EPA will engage the community in the evaluation of final options which will be used as part of a long-term remedy for Libby.
    • More Information »
      As promised, EPA will conduct a quantitative, cumulative human health risk assessment. The human health risk assessment will evaluate exposures to adults, teenagers, and children conducting a variety of activities throughout the Libby valley such as housework, playing in the yard or at school, walking, bicycling, or working in an office or outside. Site-specific remedial decision-making incorporates the data gathered in the risk assessment. Consideration of risk is one of the "nine criteria" EPA uses to make remedial decisions. The other criteria include such factors as long-term protectiveness, technical feasibility, economics and community acceptance. We will engage the community in the evaluation of final cleanup options for Libby. We will consider all potential cleanup options as part of a long-term remedy for the site.
  • Will EPA be using the draft toxicity values and preliminary risk assessment information to guide the cleanup?
    The draft toxicity values will help EPA and the community determine the best path forward for asbestos cleanup and the protection of public health. EPA reviews its cleanup programs for possible improvements. The 2011 cleanup plans were more rigorous than in previous years. They included:
    • Removing asbestos from alleys next to properties being cleaned up.
    • No longer leaving "pockets” of soil not requiring removal in the middle of an area that is being cleaned up.
    • No longer leaving landscaping such as trees and shrubs in contaminated soil.
    • Cleanup of properties next to properties undergoing cleanup.
    • Conducting a neighborhood-by-neighborhood approach to cleanup activities.
    • Conducting extensive activity-based sampling to:
       • Identify background and potential for recontamination.
       • Add to the exposure data collected at Libby.
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    Progress of Cleanup

  • How many properties has EPA remediated at Libby?
    EPA has cleaned up over 1,600 properties in both Libby and Troy. This included removing soil, insulation and debris that contained asbestos. EPA has also conducted cleanup actions at the former mine facilities and at schools in Libby. The cleanup activities continue at over 100 properties per year.
    • More Information »
      As of October 2011, EPA, with the support of Montana Department of Environmental Quality, remediated 1,603 commercial and residential properties in Libby and Troy, significantly reducing risks to area families. The agencies removed about 947,000 cubic yards of contaminated soil, 25, 323 cubic yards of asbestos-contaminated vermiculite attic insulation and 43,164 cubic yards of asbestos-containing debris. EPA also conducted response actions to reduce risks at former processing facilities, school yards and various abandoned waste piles. In the spring of 2011, EPA began comprehensive cleanup work at Riverfront Park, site of the former export plant (Operable Unit 1). Remediation of the former screening plant (Operable Unit 2) was completed in 2010.

      Institutional controls to manage residual contamination in Operable Units 1 and 2 are being developed. EPA and Montana Department of Environmental Quality are working with property owners, the Operation and Maintenance Workgroup, the city of Libby and the City/County Board of Health to develop proprietary and other land-use management programs for Operable Units 1 and 2. In addition, EPA is a member of the U-Dig Utility Locate Service for Lincoln and Flathead counties. A call to U-Dig (406-755-8344 or 800-551-8344) will provide information to property owners and contractors about the location of potential residual subsurface contamination before excavation projects begin.
  • After being in the emergency "removal" phase for almost eight years, why must EPA now transition to the "remedial" phase?
    Environmental law divides response activities into two broad categories: removal actions and remedial actions. The removal actions were the first steps EPA took at Libby. They were conducted to immediately reduce the threat posed to human health. EPA has already completed much of the Libby cleanup and removed the most significant sources of asbestos. Although removal actions will continue, the next phase is completion of remedial actions. This will include implementing control measures and remedies. The control measures will minimize potential future human exposure to asbestos and that soil covers are not disturbed. The remedies will provide future long-term maintenance of soil covers, and air monitoring to ensure the remedies continue to protect the public health.
    • More Information »
      CERCLA (Superfund law) and the National Contingency Plan (the primary regulation for Superfund) divide response activities into two broad categories: removal and remedial. Removal actions are typically described as time-sensitive responses to public health threats.

      EPA determined that it was beneficial to move forward initially at Libby under its removal authority because there was an immediate risk to public health and welfare. The removal actions were needed to mitigate an emergency and are consistent with the remedial options.

      EPA has already completed significant cleanup and removed the most significant sources of asbestos. A full remedial program is needed to establish operation and maintenance requirements and land use and other institutional controls. The remedial plans identified in the Records of Decision (RODs) represent a comprehensive remedy for the site to include excavation, capping, operation and maintenance, and institutional controls. Institutional controls will help minimize the potential for human exposure to contamination and protect the integrity of the remedy. While land use controls may allow residential, commercial, and recreational land use, they will limit uses that might compromise the remedy. Long-term maintenance of the backfilled areas and covers, including covers placed during previous response actions, will be required. Monitoring will be used to ensure the institutional controls are protective into the future.
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    Public Health Emergency

  • Why did EPA declare a public health emergency (PHE) in Libby?
    Asbestos is a known hazardous substance. Libby Amphibole asbestos (LA) had been released throughout the Libby area due to the vermiculite mining. Hundreds of cases of asbestos-related disease had been documented in the communities of Libby and Troy. The occurrence of asbestos-related diseases was not limited to the mine workers. It was also spread throughout the population. Therefore, EPA declared a public health emergency in Libby due to the serious health impacts from asbestos contamination. As a result of the declaration, EPA works closely with the U.S. Department of Health and Human Services to provide needed asbestos-related medical care to Libby and Troy residents.
    • More Information »
      EPA's reasons for declaring a public health emergency are described in the Determination and Findings of Public Health Emergency for the Libby Asbestos Site, issued by EPA's Administrator Lisa Jackson on June 17, 2009, as well as other documents found at www.epa.gov/libby/phe.html. The public health emergency recognizes the serious health impacts from asbestos contamination in Libby. EPA is working closely with the U.S. Department of Health and Human Services, which will help provide needed asbestos-related medical care to Libby and Troy residents. While EPA's ongoing clean-up efforts have greatly reduced exposure, there still exists a significant threat to public health from actual and potential releases from the site.

      EPA will continue to move aggressively to clean up the Libby Asbestos site. This site is unique with respect to the multiplicity of exposure routes, the cumulative exposures experienced by community members and adverse health effects from asbestos exposure already present and documented in the residents.
  • Will the public health emergency (PHE) determination change what EPA is doing in Libby?
    No. EPA's cleanup work will continue as planned. This will include yard cleanup and removal of uncontained vermiculite insulation in homes and buildings. It also includes cleanup and restoration of the former vermiculite mine facilities.
  • What was the basis for EPA's determination of a public health emergency (PHE)?
    The public health emergency was based on a number of factors.

    These included:
    • Multiple sources of potential exposure to asbestos.
    • High number of asbestos-related diseases in the communities of Libby and Troy.
    • Limited medical care.
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    Public Health Risks

  • How serious is the health situation in Libby?
    EPA determined there were high rates of exposures to asbestos in the community. This resulted in asbestos-related illnesses and death. Investigations found that the occurrence of asbestos-related disease in the Libby area was significantly higher than the national average. Therefore, EPA determined there was a public health emergency in Libby. Cleanup at Libby has been occurring since November 1999. EPA has made much progress in reducing the amount of asbestos in the Libby area. Although there is much less asbestos in Libby than there was 10 years ago, there are still potential health risks because it will never be possible to remove all the asbestos from the Libby area. EPA will continue to take an active cleanup approach to reduce the risks of exposure to asbestos.
    • More Information »
      EPA placed the Libby Asbestos site on the Superfund National Priorities List because environmental and epidemiological data indicated that unacceptable exposures to asbestos in the community had resulted in illness and death. Since 1999, EPA has been engaged in scientific study and cleanup work in the community. While cleanup actions addressing sources of Libby asbestos have significantly reduced asbestos levels and health risks, serious health impacts associated with past exposures persist.

      In June 2009, EPA made a determination under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) that conditions at the site constituted a public health emergency. This determination recognizes the serious impact to public health from the contamination at Libby and underscores the need for further action and health care for area residents who have been or may be exposed to asbestos. Investigations performed by the Agency for Toxic Substance and Disease Registry have found the incidence of asbestosis, a lung condition, in the Libby area to be significantly higher than the national average for the period from 1979-1998. Please refer to the Libby Public Health Emergency Web page for additional information.
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    Records of Decision/Containment Remedies

  • Were comments from citizens, local government and other concerned stakeholders responded to before the Records of Decision for Operable Unit 1 and Operable Unit 2 were issued?
    Yes. EPA considered the comments received before issuing the Records of Decision (ROD) for Operable Units (OUs) 1 and 2. A total of nineteen comment submissions were made by seventeen individuals or groups. Each comment and a response from EPA were included in the RODs for OUs 1 and 2.
    • More Information »
      EPA considered the comments received before issuing the Records of Decision. The responses to public comments on the proposed plans were included in the Records of Decision. EPA held a public comment period and public meeting on the proposed plans for Operable Units 1 and 2.

      A comprehensive responsiveness summary to the comments received was incorporated into the Records of Decision for Operable Units 1 and 2. Seventeen individuals or groups submitted comments for a total of nineteen comment submissions. Each comment (or a Response Summary of each) relevant to OU1 and OU2 was followed by EPA's response in the responsiveness summaries. Please refer to the OU1 and OU2 Records of Decision including the Responsiveness Summaries posted at Libby OU Documents.
  • Why did EPA select containment instead of removing all of the contaminants in Operable Units 1 and 2?
    Since asbestos is naturally occurring, it is not possible to remove all of it from the Libby area. EPA needed to select a remedy which minimized the potential for exposure to the asbestos. A comprehensive remedy evaluation was conducted. Based on this, containment and removal appeared to be the most effective remedies. This is done by removing asbestos-contaminated soil at the surface, and then covering the remaining soil with soil. This practice, as well as continued maintenance of the cover and land use controls, prevents the asbestos from becoming airborne.
    • More Information »
      Since asbestos is naturally occurring, it is not feasible for EPA to remove all asbestos from the Libby area. However, EPA believes that its actions will reduce risks as specified in federal Superfund regulations. As described in the Records of Decision for Operable Unit 1 and Operable Unit 2, EPA is required to use a comprehensive evaluation process to select the remedy. The selected remedies will eliminate the remaining exposure pathway to Libby Amphibole asbestos contamination by a combination of containment (with soil covers) and removal (excavation and disposal). Land use and other institutional controls along with monitoring and required five-year reviews will provide assurance that the integrity of the remedies will be protected.

      EPA believes that by breaking the soil-to-air exposure pathway, containment is an effective remedy. Containment remedies, including maintenance and land use and other institutional controls, are a viable approach to protect human health and the environment. The remedies will be revisited regularly to determine if any modification is needed. For additional information, please refer to the Records of Decision for OUs 1 and 2 at Libby OU Documents.
  • When will EPA review the effectiveness of the containment remedies in Operable Units 1 and 2?
    By law, EPA is required to periodically review the remedial actions where contaminants have been left in place. The reviews are conducted at least every five years. EPA will also review the remedies in place at Operable Units 1 and 2 when new toxicity data are available. If unacceptable exposures to asbestos are identified, EPA will take the necessary action to reduce potential exposures.
    • More Information »
      The Superfund law requires EPA to review the remedial actions at Superfund sites where wastes have been left in place. These reviews are required to be conducted at least every five years. The purpose of the five-year review is to determine if the actions remain protective of human health and the environment.

      EPA will also conduct a review to evaluate effectiveness of the remedies in Operable Units 1 and 2, when new information concerning toxicity factors is available. If unacceptable exposures are identified, EPA will take action as necessary to ensure that the soil-to-air pathway is broken. Actions may include additional excavation, improving covers, and/or strengthening land use and other institutional controls. These controls are non-engineered instruments, such as administrative and legal controls, that help minimize the potential for human exposure to contamination and/or protect the integrity of the remedy.
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    Reducing Residents' Exposure to Libby Amphibole Asbestos

  • What can Libby residents do to reduce their exposures to LA?
    Asbestos is hazardous when inhaled. Therefore, there are steps that can be taken to prevent the asbestos from becoming airborne. Thoroughly water your lawn, yard or garden before mowing, digging or disturbing the soil. Keep the lawn healthy to prevent bare spots of exposed soil. Rinse any yard tools and hands outside in the work area so that the asbestos is not brought into the home. Do not burn firewood from the Libby valley in your wood stove. Use HEPA filter vacuums to vacuum your carpets. If you see any vermiculite inside your house or in your yard, contact the EPA Environmental Resource Specialist at 406-291-5335.
    • More Information »
      Inhalation or breathing is the pathway of concern in Libby. Generally, Libby residents should avoid or at least minimize activities that stir up dust. While concentrations of asbestos in Libby's air have been significantly reduced since EPA began its cleanup work in Libby, it is still important for residents to minimize the potential for exposure to LA. Here are a few precautions that Libby residents can take to reduce exposures:

      • Thoroughly water your lawn before mowing it.
      • Maintain a healthy lawn to prevent bare spots.
      • Work in your garden when it is damp so that you do not stir up dust.
      • Following work in your yard, rinse gardening tools and hands outside within your work area after each use and before you go inside your home.
      • Call the Environmental Resource Specialist if you see any vermiculite on your property.
      • Prior to conducting renovation or remodeling work, consult with the Environmental Resource Specialist to determine how to prevent exposures to asbestos-containing vermiculite.
      • Use HEPA filter vacuums to vacuum your carpets. Never vacuum areas that may contain vermiculite with a regular vacuum.
      • Cut and gather firewood outside of the Libby valley. Do not burn firewood cut or gathered from the Libby valley in your wood stove.
      • Additional information on best management practices to reduce LA exposures is provided on the Community Involvement Documents page of this website.
  • If my work requires me to disturb soil and raise dust (excavator, landscaper), what can I do to reduce exposure?
    Asbestos is hazardous when inhaled. Therefore, your employer should have a program to protect you from potential exposure. This includes evaluating your potential for exposure. Then your employer should identify the proper equipment to prevent inhalation of asbestos. Simple precautions include:
    • Ask the property owner if they know where vermiculite might be present on their property.
    • Stop work if vermiculite is discovered. Cover or wet down the material.
    • Do not disturb areas where you can see vermiculite.
    • Water down the work areas to reduce dust.
    • Rinse off any equipment within your work area before leaving the site.
    • Contact the Environmental Resource Specialist at 406-291-5335.
    • More Information »
      Inhalation or breathing is one of the pathways of concern in Libby. Your employer should implement a respiratory protection program that evaluates your exposure and identifies the protective equipment necessary to control exposure. Other precautions include:
      • Ask the property owner if they know where vermiculite might be present on their property.
      • Stop work to assess the volume of vermiculite. Cover or wet down the material.
      • Do not disturb areas where you can see vermiculite.
      • Contact the Environmental Resource Specialist.
      • Water down the work areas to reduce dust.
      • Rinse off any equipment within your work area before leaving the site.
      • Refer to Libby Community Involvement Documents for a series of fact sheets, revised by EPA in 2013, that provides information on best management practices to reduce LA exposures.
  • What can parents do to reduce exposures to children?
    Asbestos is hazardous when inhaled. Therefore, the most important thing you can do is reduce the potential for your child to come in contact with asbestos. Have your property investigated and cleaned up if necessary. Do not let your child dig or play in dirt contaminated with asbestos. Thoroughly water your lawn, yard or garden before mowing, digging or disturbing the soil. Keep the lawn healthy to prevent bare spots of exposed soil. Use HEPA filter vacuums to vacuum your carpets.
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    Residential Cleanups

  • What procedures are used during interior residential cleanups?
    There are two sets of procedures used during interior cleanups at residences. One is for attic insulation and one is for interior living spaces. Attic insulation is removed using a vacuum truck. Afterwards, small cracks and openings are sealed and plugged. Then a visual inspection is performed to identify any remaining insulation. If there are no visual signs of insulation, a material is applied which immobilizes any remaining fibers. The last step is conducting clearance sampling to ensure the area meets EPA’s clearance criteria. For interior living spaces, HEPA vacuums are used to clean carpets and furniture. Moist cloths are used to clean surfaces. A visual inspection is then performed. The last step is conducting aggressive air sampling to ensure the area meets EPA’s clearance criteria.
    • More Information »
      The bulk removal of attic insulation is accomplished using a vacuum truck. Once the material is removed, detailing is performed by sealing and plugging any small cracks and openings. Then a visual inspection is performed, and if no signs of contamination are present, an encapsulant is applied. The encapsulant is used to immobilize remaining fibers. After these steps are completed, clearance sampling is performed to demonstrate that the area meets EPA's clearance criteria.

      In interior living spaces, vacuums with high efficiency particulate air filters, referred to as HEPA vacuums, and moist cloths, are used to clean all surfaces, and carpets and furniture are vacuumed. Drawers and closets are not opened unless there is a need to inspect for fallen vermiculite insulation. A visual inspection is then performed and aggressive air sampling is conducted to demonstrate attainment of EPA's clearance criteria.
  • What procedures are used during exterior residential cleanups?
    Exterior cleanups at residences are performed by removing visible vermiculite. Soils are excavated to a depth not greater than 18 inches in gardens and 12 inches in all other areas. After excavation, a visual inspection is done and clearance samples are collected to determine if EPA's clearance criteria are met. If the criteria are not met, excavation continues in 6-inch deep-increments until the clearance criteria are met or up to a depth of 3 feet is reached. At the bottom of the 3-foot excavation, an orange fencing barrier is laid down. This is done to indicate the presence of potentially contaminated soil in case future excavations go beyond 3 feet. Backfill is placed to bring the property back to grade and then other restoration actions are completed.
    • More Information »
      To prepare for an exterior cleanup, water tanks and earth moving equipment are mobilized. Bulk removals are performed by excavating 12 or more inches of soil in the identified cleanup areas. Visible vermiculite is removed. Earth moving equipment is used in the open areas and hand digging is done around tree roots, foundations and concrete drives and sidewalks. After 12 inches of soil are removed, a visual inspection is performed and the clearance samples are collected to determine if EPA's clearance criteria are met. If the criteria are not met, excavation continues in six-inch-deep increments until the clearance criteria are met or until a depth of three feet is reached. If three feet of soil are removed, an orange fencing barrier is laid down to indicate the presence of potentially contaminated soil (this is noted in the property file in case future excavations go beyond three feet). Backfill is placed to bring the property back to grade, and then other restoration actions are completed on the property. Information on sampling procedures is available at Libby Sampling Program Documents.
  • Does EPA test the backfill soil brought in from outside of town?
    Yes. Only soil that has been tested and found to be non-detect for Libby Amphibole asbestos (LA) using a method called polarized visual area estimation (PLM-VE) is used as backfill. Backfill soil is also visually inspected for vermiculite.
    • More Information »
      Restoration fill used in Libby and Troy is tested to demonstrate that it meets project-specific physical characteristics. Only fill that is non-detect using polarized light microscopy-visual area estimation (PLM-VE) for Libby Amphibole asbestos (LA) and visual inspection for vermiculite is used for restoration.
  • Have property owners been informed that there is the potential that EPA may have to revisit their property once final cleanup decisions are made?
    Yes. This topic has been discussed in a number of public meetings. Letters have also been sent to homeowners before and after removal work. The letters indicate that there is a possibility EPA may need to return to the property for additional sampling and cleanup.

    Examples of the letters sent to homeowners are provided at Community Involvement Documents.
  • What if a community member finds areas of contamination that were left behind by EPA?
    If you discover areas of vermiculite left behind by EPA, please contact the Environmental Resource Specialist (ERS). The ERS can be reached at 406-291-5335. It is also a good idea to call the ERS before doing any remodeling or excavation at the property. The ERS is available to answer any other questions about vermiculite.
    • More Information »
      If you discover vermiculite when remodeling or doing yard work within the Libby Asbestos Superfund Site, contact the local Environmental Resource Specialist (ERS). The ERS will provide on-the-spot answers to questions. It's also a good idea to consult with the ERS before a remodeling or excavation project is started on property in the Libby area. Please contact the ERS at 406-291-5335. Please also contact the ERS at that same number for answers to other vermiculite questions.

      It is important to be able to recognize vermiculite, should you encounter it. If you do not know what it looks like, please visit
      the EPA Information Center office, at 108 E.9th Street in Libby, to view vermiculite samples and to obtain brochures about vermiculite removal. Since it isn't possible to visually identity whether or not vermiculite is contaminated with asbestos, it is safest to assume that all vermiculite contains asbestos.
  • Is EPA still performing interior cleanups?
    Yes. EPA continues conducting interior cleanups. To date, over 750 interior cleanups have been completed at properties in Libby and Troy.
    • More Information »
      Yes. EPA is continuing to conduct interior cleanups. Through October 2010, 67 interior cleanups in Troy and 35 in Libby were completed. EPA is performing General Property Investigations, which will add to the number of additional interior cleanups for 2011. Altogether, EPA has completed interior cleanups at over 750 properties.
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    Risk Assessment/Libby Action Plan Toxicity Studies

  • What are the toxicity studies referred to as the Libby Action Plan (LAP)?
    The Libby Action Plan contains studies to evaluate the characteristics and analysis of Libby Amphibole asbestos (LA). The results of the studies will help EPA better understand the toxicity of LA.
    • More Information »
      In February 2007, EPA approved funding for the Libby Action Plan, which contains studies to examine analytical methods, epidemiology, and toxicology related to Libby Amphibole asbestos (LA). These studies are conducted by the National Health and Environmental Effects Research Laboratory and Region 8 scientists. The results of these studies will allow EPA to better understand the toxicity of LA, support the risk assessment and help the Agency set final site-specific cleanup goals.
  • Why is EPA proceeding with cleanup decisions before a final risk assessment is completed?
    EPA recognizes that residents in the area have questions about conducting cleanup activities before the risk assessment is completed. The goal of the cleanup is to quickly minimize exposure to asbestos. Minimizing the exposure reduces the human health risks. EPA will evaluate the effectiveness of the remedies at least every five years. This is done to ensure the remedies continue to protect human health and the environment.
    • More Information »
      EPA recognizes that residents in Libby and the surrounding area have varied views on implementing cleanup before a final risk assessment is completed. However, EPA's goal in moving forward with cleanup is to eliminate the pathways of exposure to reduce risks to human health. As noted in EPA's Responsiveness Summaries incorporated into the Records of Decision for OUs 1 and 2, which can be found at Operable Unit (OU) Documents:

      EPA continues to study the effects of Libby Amphibole asbestos (LA) contamination on human health and the environment. While these important studies are underway, current findings indicate that it is necessary to move forward with remedies at OU1 and OU2 to prevent continued exposure to Libby asbestos. These remedies will address both surface and subsurface soil. The approach will also provide land use controls and other institutional controls and define maintenance requirements for any subsurface contamination left in place.

      Following implementation of the remedy, EPA will conduct a post-construction quantitative risk assessment, including activity-based sampling and new Libby Amphibole asbestos (LA)-specific toxicity factors, to confirm the effectiveness of the remedy. Remedies selected in RODs are continually subject to modification based on new information. EPA will evaluate the effectiveness of the remedy at least every five years to ensure protectiveness. These routine evaluations will include any new information gained from on-going Libby Action Plan investigations. In addition, when the site-wide risk assessment is complete, EPA will re-evaluate the remedy in accordance with the review requirements in CERCLA Section 121 (c).
  • Why has it taken so long to determine the toxicity of Libby Amphibole asbestos (LA)?
    In 2007, EPA began this process specific to Libby Amphibole asbestos (LA). This involved evaluating:
    • Data on the rate and frequency of LA-related diseases.
    • Various laboratory toxicity studies.
    • Methods for LA analysis.
    The goal is to produce a credible and useable toxicity assessment to support the risk assessment. The studies are proceeding as rapidly as the science will allow.

    Estimating the toxicity of a material is a complex process that involves reviewing vast amounts of scientific data. Estimates of Libby Amphibole asbestos (LA) toxicity were developed based on this review. The estimates were presented for review by the public, scientists from EPA and other federal agencies, and independent scientists. The process usually takes about two years. EPA hopes that this process will be completed by the end of 2012.
    • More Information »
      Currently, EPA is relying on existing asbestos toxicity information to make site decisions. However, some people believe that the existing toxicity data are not directly pertinent to LA. Additionally, a toxicity factor does not exist for non-cancer health effects. Beginning in 2007, EPA began a comprehensive series of studies specific to LA involving evaluations of epidemiological information, laboratory toxicity studies, and development and validation of analytical methods.

      This comprehensive approach is called the Libby Action Plan (LAP). The studies are proceeding as rapidly as the science will allow. The LAP is expected to produce a scientifically credible toxicity assessment to support the site-wide risk assessment for the Libby site. When these studies are completed, they will be used to develop a site-specific quantitative human health risk assessment.

      While these studies are underway, EPA has taken an aggressive approach to reducing exposure by the removal and/or capping of asbestos containing materials. This has resulted in a significant reduction in the ambient air concentrations of asbestos in Libby. Asbestos concentrations in ambient air are now approximately 10,000 times lower than the reported air concentrations in downtown Libby during the period when the mine and milling plants were in operation.

      EPA will complete a site-wide risk assessment that includes Libby-specific exposure data and the newest toxicity information. For more information on EPA's risk assessment approach at Libby please refer to Libby Asbestos: Human Health Assessment.
  • Will the toxicology studies enable EPA to assess the toxicity of Libby Amphibole asbestos (LA) at various doses and to susceptible populations?
    The goal is to produce a credible toxicity assessment to support the site-wide risk assessment. The studies will be used in the toxicity assessment of Libby Amphibole asbestos (LA).
    • More Information »
      The planned investigations will provide data on pleural disease, cardiovascular disease, autoimmune disease, cancer and other diseases that may be caused by LA. The investigations will also include dose-response analyses and dosimetry to better understand health effects in people of various ages and health status.
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    Sampling and Analytical Methods

  • What types of sampling methods does EPA use at the Libby Asbestos site?
    EPA uses two types of sampling methods for air samples and two methods for soil and bulk material samples. The two methods used for air samples are Phase Contrast Microscopy (PCM) and Transmission Electron Microscopy (TEM). PCM is used for measuring fibers in dust. However, this method is not capable of identifying asbestos fibers. TEM is the most sophisticated method available. It can provide images at significantly higher resolutions than other methods. This allows the user to examine fine details and identify specific asbestos fibers. The two methods used for soil and bulk material samples are Polarized Light Microscopy (PLM), and PLM-Visual Estimation (PLM-VE). PLM is the standard method used to confirm the presence or absence of asbestos in a sample. PLM-VE is specifically used for the Libby site. It is based on the PLM method. However, it also uses a visual comparison of the number of fibers noted in a defined area to laboratory standards with a known concentration of fibers. This method is more reliable for detecting low concentrations of LA in a cost-effective manner.
    • More Information »
      EPA uses a number of sampling methods at the Libby Asbestos site. Below is a chart showing the different methods, which media they are used for, such as soil or air, the sensitivity levels and for what types of use.

      Method Media & Sensitivity Use Qualitative Quantitative
      PCM
      [OSHA ID-160 or NIOSH 7400]
      Air, non-specific Occupational monitoring ± ±
      PLM
      [NIOSH 9002]
      Soil, bulk material, <1% Soil screening x  
      PLMve*
      [SRC-Libby-03]
      Soil, bulk material, <0.2% Soil screening x  
      TEM
      [ISO 10312]
      Air Ambient air monitoring
      Activity-based sampling
        x
      Indicates the method can be qualitative or quantitative. It has been the standard in occupational exposure monitoring and is used in industrial hygiene as a quantitative method.

      *ve Visual inspection compares the soil preparation on the slide to standards at 0.2% and 1% LA in soils.

      For more detailed information about the various sampling and analytical methods that EPA uses at the Libby Asbestos site, visit
      Sampling and Analysis at Libby.
  • What is Activity-Based Sampling (ABS)?
    Activity-based sampling (ABS) is a method used to measure the amount of asbestos in the air caused by disturbing soil or dust. Air samples are collected from participants conducting typical daily activities. These activities include raking, mowing, digging, bike riding, etc. The samples are collected from within the breathing zone during the activity. The samples are then analyzed at a laboratory to determine the amount of airborne asbestos.
    • More Information »
      Activity-based sampling or ABS is a sampling method to measure the level of airborne asbestos that occurs while participants are engaged in typical activities, such as raking, digging, mowing, riding bikes, etc. Air samples are taken from the breathing zone during these activities to measure airborne contamination caused by disturbing soil or dust. This measurement tool is a part of EPA's overall site evaluation. Contractors measuring ABS can be seen wearing respirators and white Tyvek suits during ABS work because such equipment is required by health and safety regulations.

      All ABS samples collect data on fibers that are then analyzed by Transmission Electron Microscopy (TEM) and it is these data that are used in evaluations of potential health risk(s). TEM is a more complex analytical method than Phase Contrast Microscopy (PCM), Polarized Light Microscopy (PLM) and Polarized Light Microscopy-Visual Estimate (PLM-VE). TEM can distinguish between asbestos and non-asbestos fibers as well as asbestos types and can be used at higher magnifications, enabling identification of smaller asbestos fibers.

      The most recent ABS summary report was released in June, 2010 and can be found at Sampling Program Documents.
  • Are ABS sampling scenarios selected to replicate actual activities on the residential property being sampled?
    Yes. Some activity-based-sampling (ABS) scenarios are meant to represent activities that happen at all residences while others are intended to estimate higher, more conservative exposures. The scenarios selected, mowing, digging and raking, are assumed to occur at each property as part of normal yard maintenance. However, it is not possible to evaluate every potential activity which may disturb soil or dust.
    • More Information »
      While one of the objectives of this activity-based sampling (ABS) program is to evaluate exposure of residents from soil disturbances in their yards, it is not feasible to evaluate every possible type of disturbance. As such, three scenarios were selected which are considered to be realistic and representative examples of disturbances at all residential properties. To ensure consistency among properties, the scripted activities are performed in the same manner at each residence.

      For more information, please see the 2010 Sampling and Analysis Plan for OU4 Activity-Based Sampling.
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    Schools

  • Are the Libby schools safe even though there is vermiculite in the walls?
    EPA places a high priority on protecting school children and staff from exposure to even low levels of asbestos. Intact and undisturbed asbestos materials generally do not pose a health risk. Exterior removal actions were completed at all public schools in Libby in 2002. Additional interior and exterior removal actions have been performed when required. EPA completed multiple sampling and investigations at the schools. This included ambient-air testing and activity-based sampling (ABS). The objective of the sampling was to determine if residual asbestos poses risks to students and staff. It also identified whether further cleanup actions at the schools were necessary. EPA will continue sampling at the Libby schools to confirm the effectiveness of past removal actions.
    • More Information »
      EPA places a high priority on protecting school children and employees from exposure to even low levels of asbestos. Intact and undisturbed asbestos materials generally do not pose a health risk. EPA's asbestos program for schools, mandated by the Asbestos Hazard Emergency Response Act (AHERA), is based on the principle of "in-place" management of asbestos containing material (ACM). Please refer to EPA's asbestos site for school asbestos management information. EPA's approach is designed to prevent exposure to asbestos-containing materials and to actively monitor and manage them in place. Removal of asbestos-containing materials is not usually necessary unless the material is severely damaged or will be disturbed by a building demolition or renovation project.

      Exterior removal actions were completed at all public schools in Libby in 2002 and subsequent exterior and interior removal actions have been performed when required. EPA has conducted multiple sampling and investigations at the schools including ambient-air testing and activity-based sampling. The objective of the school investigation program is to determine if residual LA at schools in Libby poses risks to students, teachers or maintenance staff, or if further cleanup actions at schools are needed. Recent activity-based sampling results are available on this website.

      EPA will continue sampling at the Libby schools to confirm the effectiveness of past removal actions. A final remedy will be selected in the forthcoming ROD for Operable Unit 4. In the meantime, the Environmental Resource Specialist program will respond to any incidents at the school that might result in Libby Amphibole asbestos exposures. Please contact the Environmental Resource Specialist at 406-291-5335 with questions.
  • Why didn't EPA use Transmission Electron Microscopy (TEM) to analyze the soils at the schools instead of Polarized Light Microscopy Visual Estimate (PLM-VE), which cannot detect asbestos in low concentrations (below 1 percent)?
    Transmission Electron Microscopy (TEM) is the most sophisticated method available for measuring asbestos in air samples. A known volume of air is passed through a filter and TEM analyzes asbestos fibers on the filter. It is not used for soil samples. Polarized Light Microscopy (PLM) is the standard method used to confirm the presence or absence of asbestos in a soil or bulk material sample. PLM-VE is specifically used for the Libby site. It is based on the PLM method. However, it also uses a visual comparison of the number of fibers noted in a defined area to laboratory standards with a known concentration of fibers. This method is more reliable for detecting low concentrations of LA in a cost-effective manner.
    • More Information »
      EPA does not use TEM analysis on soils because we have no way of relating concentrations in the soil to concentrations in the air. We use PLM and PLM-VE as a screening tool to indicate where additional investigation is required based on the current response action levels. There are no methods currently available to accurately estimate exposures associated with the disturbance of soil which is why we perform activity-based sampling (ABS). Personal monitoring in the form of ABS is the best technique to estimate exposure. ABS is a sampling method to measure the level of airborne asbestos that occurs while participants are engaged in typical activities, such as raking, digging, mowing, riding bikes, etc. Therefore, EPA performs ABS on soils that collect data on fibers that are then analyzed by TEM and it is these data that are used in evaluations of potential health risk(s).
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    Temporary Relocation of Property Owners in Libby

  • Are Libby residents temporarily relocated during remediation?
    Yes. Libby residents are offered temporary relocation during asbestos removals. This is generally done only when two exits to the home cannot be maintained. EPA’s onsite contractor will coordinate with the property owner on:
    • All sampling cleanup activities.
    • Temporary relocation arrangements.
    • Return to the property upon completion of the removals.
    • Reimbursement for costs during relocation.
    • More Information »
      Libby residents are offered temporary relocation during interior removals and exterior removals when two exits cannot be maintained. EPA's onsite contractor coordinates sampling and cleanups. Coordination includes briefing residents on the scope of work, arranging for temporary relocation, facilitating interactions between the field crew and residents, obtaining residents' approval of the planned work, facilitating residents' return to the property, and reimbursing residents for their costs during relocation. Support is also provided to business owners to help resolve issues regarding temporary relocation.
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    Worker Concerns

  • Who should tradespeople and firefighters working in Libby contact with questions about dealing with potentially contaminated material?
    EPA is concerned about tradespeople and firefighters who may encounter asbestos as part of their work. It is therefore important to have a long-term program to manage these potential exposures. Workers are urged to contact the Environmental Resource Specialist (ERS) at 406-291-5335 at any time. The ERS is available to answer any questions about asbestos. The ERS will remain in Libby after cleanup activities are complete as a resource to the workers and citizens. EPA will continue to provide training to workers to help them manage exposures to asbestos.
    • More Information »
      EPA is concerned about tradespeople and firefighters who might encounter asbestos-contaminated material during the course of their work. That is why it is so important to have an effective, ongoing program in place to manage these potential exposures over the long term. EPA has made the Environmental Resource Specialist (ERS) program available to tradespeople and firefighters to address their concerns when they encounter asbestos materials or suspect asbestos materials are present. Please refer to Asbestos in Your Home and Libby Public Health Emergency for more information. Tradespeople and firefighters who encounter vermiculite are invited to contact the ERS at 406-291-5335. The agency plans for the ERS program to remain in Libby after EPA remedial activities are completed to answer questions about vermiculite from residents and businesses. Furthermore, EPA has and will continue to provide training to tradespeople and firefighters in Libby, so they can manage their exposure to Libby Amphibole asbestos.

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