Company History & the Libby Disaster
W.R. Grace & Co. traces its origins to the nineteenth century, when Irish immigrant William Russell Grace built a trading and shipping empire in South America. Over the following century the company diversified into chemicals, construction materials, and specialty products, becoming a major industrial conglomerate by the mid-twentieth century. Grace's most consequential acquisition — and the one that would ultimately force it into bankruptcy — came in 1963, when it purchased the Zonolite Company of Libby, Montana.
The Zonolite Company had been mining and processing vermiculite ore from a deposit in the Cabinet Mountains above Libby since the 1920s. Vermiculite is a naturally occurring mineral that, when heated, expands into a lightweight, fire-resistant material useful as attic insulation, garden soil amendment, and an aggregate in fireproofing and construction products. At its peak, the Libby mine supplied roughly 80 percent of the world's vermiculite. What Zonolite — and later Grace — knew, but chose not to fully disclose, was that the Libby ore deposit sat alongside a seam of tremolite, a fibrous amphibole asbestos considered among the most biologically aggressive of all asbestos mineral types.
Tremolite asbestos fibers are short and needle-like. They penetrate deep lung tissue and the pleural lining with particular efficiency, and they resist the body's attempts to expel or dissolve them. Studies published as early as the 1930s had documented tremolite's hazards; internal Grace documents from the 1960s and 1970s show company hygienists and medical personnel tracking elevated fiber counts in mine air and finding abnormal chest X-rays among workers at statistically alarming rates. Instead of acting decisively on this information — by shutting down operations, installing adequate engineering controls, or warning the surrounding community — the company managed the problem internally, downplayed findings in worker communications, and continued selling Libby-sourced vermiculite products under the Zonolite brand across North America.
The Libby mine operated at full capacity through the 1980s. Over that span, thousands of men and women worked in the mine, the on-site mill, and the ore-processing facilities. They worked in clouds of dust that contained invisible asbestos fibers. They brought that dust home on their clothes, in their hair, and on their skin, exposing spouses, children, and neighbors. Libby schoolchildren played on a running track partially constructed with mine tailings. The local ice skating rink was built on a vermiculite-contaminated parcel. By the time the mine closed in 1990, the damage was done on a community-wide scale.
In 1999, an investigative series by the Seattle Post-Intelligencer brought the Libby disaster to national attention, prompting the U.S. Environmental Protection Agency to conduct an emergency response — one of only a handful ever declared in the agency's history. The EPA's investigation confirmed asbestos contamination throughout the town: in homes, businesses, parks, schools, and public spaces. More than 200 former mine workers had died of asbestos-related disease; the toll among residents, family members, and second-hand exposure victims pushed the total diagnosed population above 1,700. Libby, Montana was eventually designated a Superfund site, and EPA cleanup efforts have continued for more than two decades at a cost exceeding $600 million.
W.R. Grace filed for Chapter 11 bankruptcy protection in April 2001, citing its mounting asbestos liabilities — which by that point encompassed not only Libby claims but also thousands of claims arising from Monokote fireproofing and other asbestos-containing products the company had manufactured and sold. After a decade of reorganization proceedings, Grace's plan of reorganization was confirmed in 2011, and the WRG Asbestos PI Trust was established to receive and pay personal injury claims. Grace emerged from bankruptcy in 2014 as a reorganized specialty chemicals company; in 2016, Standard Industries acquired the company in a go-private transaction.
Products & Asbestos Exposure
W.R. Grace's asbestos liability stems from several distinct product lines and operations. The contamination pathways differ depending on whether a person was a mine worker, a construction trades worker, a homeowner, or a community resident — but the underlying hazard runs through all of them.
| Product / Material | Asbestos Type | Primary Exposure Mechanism | Who Was Exposed |
|---|---|---|---|
| Zonolite Attic Insulation | Tremolite (contaminant in vermiculite) | Disturbance of loose-fill insulation releases airborne fibers; renovation, installation, storage access | Homeowners, DIY renovators, insulation installers, HVAC technicians, electricians working in attics |
| Libby Vermiculite Ore & Mill Dust | Tremolite (amphibole) | Mining, crushing, screening, and loading operations generated high-concentration dust clouds throughout every shift | Mine workers, mill workers, truck drivers, Libby community residents, workers' family members (take-home exposure) |
| Monokote Fireproofing Spray | Chrysotile (serpentine asbestos) | Spray application to structural steel generated airborne fiber; sanding, cutting, and demolition of cured material releases fibers decades later | Ironworkers, pipefitters, sheet metal workers, electricians, painters, and others working near spray fireproofing operations (1963–1973); building occupants and demolition crews in later years |
| Vermiculite Exfoliation Plant Operations | Tremolite (contaminant in Libby ore) | Raw Libby ore was shipped to ~250 processing plants nationwide where it was heated and expanded; ore handling released fibers into plant air and surrounding areas | Plant workers, workers in nearby facilities, community residents near processing plants in cities including Minneapolis MN, Tampa FL, Baltimore/Curtis Bay MD, Phoenix AZ, and Cambridge MA |
| Zonolite Construction Aggregate & Plaster | Tremolite (contaminant) | Mixing, troweling, and sanding of Zonolite-based plaster and concrete products released fibers into the surrounding work environment | Plasterers, masons, drywall contractors, construction laborers |
| Libby Mine Tailings (Community Uses) | Tremolite | Mine waste and tailings were distributed for road fill, athletic track surfacing, and other community purposes in the Libby area | Libby schoolchildren, athletes, community members, residents near contaminated fill sites |
Of particular concern to present-day homeowners is the ongoing risk posed by Zonolite attic insulation. Because virtually all pre-1990 vermiculite insulation on the market was sourced from the Libby mine, the EPA advises that any vermiculite attic insulation should be treated as containing asbestos until proven otherwise by laboratory analysis. The agency further recommends that homeowners not disturb the insulation, not use the attic for storage, and consult a licensed asbestos professional before undertaking any renovation work that might affect the attic space.
Key Sites & Contaminated Facilities
The geographic footprint of W.R. Grace's asbestos contamination extends far beyond Libby, Montana. The company's network of vermiculite exfoliation plants, manufacturing facilities, and construction project sites created exposure hazards across the United States and in several other countries. The table below identifies the most significant sites documented in regulatory records, litigation, and EPA investigations.
| Facility / Site | Location | Years Active | Nature of Contamination |
|---|---|---|---|
| Libby Vermiculite Mine & Mill | Libby, Lincoln County, MT | 1919–1990 | Primary source site; tremolite asbestos contaminated ore, mine buildings, surrounding community, and residential properties through take-home exposure and community use of tailings |
| W.R. Grace Exfoliation Plant | Minneapolis, MN | 1950s–1980s | Processing of raw Libby ore released tremolite fibers; contamination of plant structure and surrounding properties documented by EPA |
| W.R. Grace Exfoliation Plant | Curtis Bay / Baltimore, MD | 1950s–1980s | Vermiculite ore processing; site placed on EPA watch list; worker and community exposure documented in regulatory filings |
| W.R. Grace Exfoliation Plant | Tampa, FL | 1960s–1980s | Libby ore processing; tremolite fiber release documented; former worker claims on record in trust fund databases |
| W.R. Grace Exfoliation Plant | Phoenix, AZ | 1960s–1980s | Processing facility; contamination of plant building and grounds confirmed; EPA site review conducted as part of nationwide vermiculite assessment |
| W.R. Grace Exfoliation Plant | Cambridge, MA | 1950s–1970s | Vermiculite expansion operations; fiber release into plant environment; proximity to residential areas raised community exposure concerns during EPA review |
| Monokote Application Sites (Nationwide) | Major U.S. cities (New York, Chicago, Houston, and hundreds of others) | 1963–1973 | Spray-applied asbestos fireproofing applied to structural steel in high-rise office buildings, schools, hospitals, and commercial structures; risk continues from renovation and demolition |
| Libby Asbestos Superfund Site | Libby & Troy, Lincoln County, MT | 1999–present (cleanup ongoing) | EPA-designated Superfund site encompassing the mine, mill, tailings areas, and contaminated residential and commercial properties throughout the Libby area; $600M+ in cleanup expenditures to date |
The EPA has identified and assessed more than 250 former vermiculite exfoliation plant sites across the United States as part of its Libby Amphibole Asbestos investigation. While not all of these sites show actionable contamination levels, many have required formal cleanup actions or ongoing monitoring. Workers who spent time at any of these facilities — or who lived near them — may have been exposed to tremolite asbestos released during processing operations.
The Criminal Case & What Grace Knew
The legal reckoning for W.R. Grace over the Libby disaster moved on two tracks simultaneously: a massive civil litigation and bankruptcy proceeding on one side, and an unprecedented federal criminal prosecution on the other. Both proceedings cast a harsh light on the company's internal knowledge of the hazard and its decisions about what to disclose — and what to hide.
EPA Emergency Declaration (1999–2000)
In 1999, following the Seattle Post-Intelligencer investigation, EPA dispatched a team to Libby on an emergency assessment. What they found was alarming: asbestos contamination in scores of residential properties, public spaces, and former mine facilities. In 2000, EPA invoked its rarely-used emergency authority under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) to initiate immediate cleanup actions. EPA declared Libby a public health emergency — one of the first times in the agency's history that designation had been applied to a community-wide industrial contamination event. The Agency for Toxic Substances and Disease Registry (ATSDR) conducted health screenings and found that Libby residents had rates of asbestos-related abnormality on chest X-rays roughly forty times the national average.
The 2005 Federal Criminal Indictment
In February 2005, a federal grand jury in Missoula, Montana returned a sweeping indictment against W.R. Grace & Co. and seven current and former executives, including the company's former chief executive officer. The charges included conspiracy to defraud the United States, obstruction of justice, and knowing endangerment under the Clean Air Act — the first time the federal government had charged a corporation with criminal endangerment of a community under that statute. The indictment alleged that Grace executives had known about the tremolite contamination for decades, that they had deliberately concealed health studies from regulators and workers, and that they had taken active steps to mislead EPA investigators during the 1999–2000 emergency response.
Central to the government's case were internal company documents spanning the 1960s through the 1990s. Among the most damaging: a 1969 internal memo showing that Grace was aware its Libby ore contained commercial quantities of tremolite; a series of industrial hygiene reports from the 1970s showing fiber counts in the mine air many times higher than then-permissible exposure limits; medical surveillance data showing a rising tide of asbestosis diagnoses among Libby workers; and correspondence between executives discussing the legal and political risk of making fuller disclosures to workers and the public. Documents also showed that in the early 1990s, Grace scientists internally estimated the company faced hundreds of thousands of future asbestos claims from Libby-sourced products — estimates that were never shared with shareholders or regulators.
The 2009 Acquittal and Its Aftermath
After years of pretrial litigation and delays related to the bankruptcy proceeding, the criminal trial finally began in Missoula in February 2009. In May 2009, the jury acquitted the company and all individual defendants on all counts. The acquittal was widely attributed to the difficulty of proving criminal intent beyond a reasonable doubt in a complex corporate context, and to the government's decision to charge under the rarely-litigated knowing-endangerment provision of the Clean Air Act. The acquittals were a significant blow to the government's criminal case, but they did not resolve the civil or regulatory picture.
EPA cleanup operations in Libby continued uninterrupted through the acquittal and in subsequent years. As of the mid-2020s, the agency has cleaned up or is actively working on more than 2,000 properties in the Libby area, and the remediation work is not complete. The state of Montana and the federal government have engaged in ongoing disputes about who bears ultimate financial responsibility for the remaining cleanup costs. Grace's reorganized successor, now owned by Standard Industries, has funded cleanup obligations through the reorganization trust structure, but the full extent of those obligations remains contested in ongoing proceedings.
Congressional and Regulatory Response
The Libby disaster had lasting effects on federal asbestos and environmental policy. EPA's nationwide investigation of vermiculite exfoliation plant sites led to tighter regulatory scrutiny of facilities processing potentially contaminated minerals. Congress held multiple hearings on Libby in the early 2000s, fueling legislative proposals for comprehensive federal asbestos reform — though no broad national asbestos ban was enacted in that period. In 2019, EPA took the significant step of banning new uses of chrysotile asbestos, the one remaining form in limited industrial use. Critics note that this rule does not address the vast quantities of legacy asbestos already installed in buildings, homes, and infrastructure across the country.
Trust Fund Status & Compensation Options
W.R. Grace's bankruptcy reorganization established two separate trust structures to address its asbestos liabilities: one for personal injury claimants and one specifically for homeowners with Zonolite attic insulation. Understanding both trusts — and which one applies to your situation — is important for maximizing your compensation.
WRG Asbestos PI Trust
The WRG Asbestos Personal Injury Trust was created under Grace's confirmed plan of reorganization to compensate individuals who suffered asbestos-related personal injuries as a result of exposure to W.R. Grace asbestos products. The trust currently pays claims at a payment percentage of 30.1% — meaning that if your claim is valued at $100,000, you would receive $30,100 from the trust. This payment percentage is substantially higher than many asbestos trusts, which frequently pay between 2% and 25%, reflecting the fact that Grace funded the trust at a relatively high level relative to projected claim volume at the time of confirmation.
The WRG PI Trust accepts claims for the following qualifying disease categories:
- Mesothelioma — the highest-value disease category; median trust values before the payment percentage is applied can range from the tens of thousands to well over $100,000 depending on claim strength
- Lung cancer (with asbestosis or documented significant occupational exposure)
- Other cancers — laryngeal, pharyngeal, esophageal, stomach, and colorectal cancers with documented asbestos exposure history
- Asbestosis / significant asbestos disease — documented through pulmonary function tests, chest imaging, and pathology where required
- Pleural disease — including pleural plaques and diffuse pleural thickening meeting the trust's severity thresholds
To qualify, a claimant must demonstrate both a qualifying diagnosis and a qualifying exposure — that is, documented occupational, residential, or secondary exposure to a W.R. Grace asbestos product. Exposure evidence can include employment records, union records, co-worker affidavits, product identification testimony, site records showing Grace product use, and information from asbestos litigation databases maintained by experienced plaintiff's firms.
Zonolite Attic Insulation (ZAI) Trust
The Zonolite Attic Insulation Trust is a separate fund established specifically to address property-damage claims from homeowners whose homes contain Zonolite vermiculite insulation. The ZAI Trust provides payments to help homeowners pay for professional removal and disposal of Zonolite insulation by a licensed asbestos abatement contractor. This trust does not pay personal injury claims — it is limited to property remediation costs. Homeowners who have also been personally injured (diagnosed with an asbestos-related disease attributable to Zonolite exposure) may file both a ZAI Trust claim for remediation costs and a WRG PI Trust claim for their personal injury.
Other Sources of Compensation
The WRG PI Trust is not the only potential source of compensation available to Grace exposure victims. Depending on the specifics of an individual's work history and product exposure, claims may also exist against:
- Other asbestos product manufacturers and distributors whose products were used at the same worksites
- Premises owners who failed to provide a safe working environment for contractors and tradespeople
- Other active asbestos bankruptcy trusts — there are currently more than 60 asbestos trusts, and many victims qualify for claims against multiple trusts based on overlapping product exposures
- Direct litigation against solvent defendants who have not filed for bankruptcy protection
An experienced asbestos and mesothelioma attorney will conduct a thorough exposure history and identify all potential trusts and litigation targets. Because filing deadlines vary by state — and because some trusts have time limits on submission windows — it is important to consult an attorney promptly after a diagnosis. In most states, the statute of limitations for mesothelioma claims begins to run from the date of diagnosis, not the date of exposure.
Worked for W.R. Grace or at Their Sites?
If you or a loved one was exposed to asbestos from W.R. Grace products or the Libby mine and has been diagnosed with mesothelioma, trust fund claims and lawsuits may provide significant compensation.
Frequently Asked Questions
Zonolite is a brand name for expanded vermiculite insulation that was manufactured and sold by the Zonolite Company (and later W.R. Grace & Co.) from the 1920s through 1984. It was marketed as a lightweight, fire-resistant attic insulation and was widely installed in homes across the United States and Canada during the postwar housing boom and into the 1970s and 1980s. The product has a distinctive appearance: grayish or silver-brown pebbles or granules, typically found as a loose-fill material spread across attic floors to a depth of a few inches.
The danger with Zonolite is that virtually all of the vermiculite used to make it came from the Libby, Montana mine, which was naturally contaminated with tremolite asbestos. Tremolite is a type of amphibole asbestos with needle-shaped fibers that, when airborne and inhaled, lodge in the lung tissue and pleural lining and can cause mesothelioma, asbestosis, and lung cancer — often decades after the initial exposure. When Zonolite insulation is disturbed — by walking on it, moving stored items in the attic, conducting home renovations, or doing electrical or HVAC work in the attic space — it can release invisible asbestos fibers into the air of the home. The EPA and the ATSDR both recommend treating all vermiculite attic insulation as if it contains asbestos, regardless of when or where it was purchased.
Possibly. The EPA estimates that approximately 35 million U.S. homes still contain vermiculite attic insulation, and the overwhelming majority of commercial vermiculite insulation sold before 1990 was sourced from the Libby, Montana mine. If your home was built before 1990 and has never had the attic insulation tested or replaced, there is a meaningful possibility that you have Zonolite-origin vermiculite insulation that may contain tremolite asbestos fibers.
The practical risk depends heavily on disturbance. Vermiculite insulation that is left undisturbed and sealed beneath a properly maintained attic floor poses a lower day-to-day exposure risk than insulation that is frequently accessed, moved, or disturbed by renovation activity. However, even routine attic access — reaching in to retrieve stored items, or having a contractor work in the attic space — can generate fiber levels above background concentrations.
If you suspect you have Zonolite insulation, the recommended steps are: (1) do not disturb the insulation; (2) limit attic access until the material can be assessed; (3) hire a licensed asbestos inspector to collect samples for laboratory analysis; and (4) if asbestos is confirmed, hire a licensed asbestos abatement contractor for professional removal and disposal. Remediation costs may be recoverable in whole or in part through the Zonolite Attic Insulation Trust.
Yes — and this is not a matter of speculation. Documents introduced during both civil litigation and the federal criminal prosecution in Montana established that W.R. Grace had internal knowledge of tremolite contamination at the Libby mine going back to the 1960s. Company industrial hygienists conducted air sampling studies in the 1960s and 1970s that showed fiber concentrations many times higher than then-acceptable occupational exposure limits. Company physicians tracked medical surveillance data showing an abnormally high rate of pulmonary disease and abnormal chest X-rays among Libby mine workers. Internal correspondence from the 1970s showed executives discussing the legal and political risks of disclosing the hazard more fully to workers and regulators.
Perhaps most damningly, internal documents showed that Grace scientists in the early 1990s prepared internal projections estimating the company's future asbestos liability from Libby-sourced products at hundreds of thousands of claims. These projections were not disclosed to shareholders, regulators, or the public at the time they were prepared. When EPA investigators arrived in Libby in 1999–2000, Grace executives allegedly provided misleading information about the company's historical knowledge of the hazard — conduct that formed the basis of the obstruction of justice charges in the 2005 criminal indictment. Although the executives were ultimately acquitted in 2009, the documentary record of corporate knowledge remained a central feature of the civil litigation and trust fund claims process.
Yes. W.R. Grace filed for Chapter 11 bankruptcy in April 2001, driven primarily by its mounting asbestos-related liabilities from both the Libby mine and its other asbestos product lines. After more than a decade of proceedings, the company's reorganization plan was confirmed by the bankruptcy court in 2011, and Grace emerged from bankruptcy in 2014. As part of the reorganization, two trusts were established to handle asbestos-related claims:
WRG Asbestos PI Trust: Pays personal injury claims for individuals diagnosed with mesothelioma, lung cancer, asbestosis, other qualifying cancers, or pleural disease as a result of exposure to W.R. Grace asbestos products — including Libby mine-sourced vermiculite products, Monokote fireproofing, and other Grace asbestos-containing materials. The trust currently pays at a 30.1% payment percentage. Claimants must document both a qualifying diagnosis and qualifying exposure to a Grace product or operation.
Zonolite Attic Insulation (ZAI) Trust: Pays property-damage claims to homeowners whose homes contain Zonolite vermiculite insulation, providing reimbursement toward the cost of professional asbestos abatement and remediation. This trust is separate from the PI Trust and handles property claims only, not personal injury.
Claims against both trusts are typically filed through an asbestos attorney who specializes in trust fund claims. There is no upfront cost to evaluate your potential claim — virtually all mesothelioma and asbestos attorneys work on a contingency-fee basis, meaning they are paid only if they recover compensation for you.
Filing a claim with the WRG Asbestos PI Trust involves several steps, and it is strongly advisable to work with an experienced asbestos attorney rather than navigating the process alone. The general process proceeds as follows:
Step 1 — Gather medical records. You will need documentation of your asbestos-related diagnosis: pathology reports, radiology reports (CT scans, chest X-rays), pulmonary function studies, and treating physician records. The specific documents required depend on the disease category you are claiming under; mesothelioma requires pathological confirmation, while lesser diseases may be substantiated through imaging alone.
Step 2 — Document your exposure to Grace products. This is where an attorney's assistance is most valuable. You will need to establish that you were exposed to a W.R. Grace product — whether that means Libby vermiculite, Zonolite insulation, Monokote fireproofing, or another Grace-branded product. Evidence can include employer records, union employment records, Social Security earnings histories, co-worker affidavits, and site-specific product identification records drawn from asbestos litigation databases that track which products were used at which jobsites.
Step 3 — Submit the claim to the trust. Your attorney will prepare and submit the formal claim package to the WRG PI Trust. The trust will review the claim for completeness and eligibility, apply its current payment percentage (30.1%), and issue payment. Most claims are resolved through the trust's expedited review process.
Step 4 — Identify other liable parties. An experienced attorney will simultaneously assess whether you have claims against other asbestos trusts or solvent defendants, which can significantly increase your total recovery. Many mesothelioma victims qualify for claims against a dozen or more trusts simultaneously, and some may also have viable claims in direct litigation.
If you or a family member has been diagnosed with mesothelioma or another asbestos-related disease and believe W.R. Grace products may have been involved in the exposure, contact a mesothelioma attorney for a free case evaluation. Statutes of limitations vary by state and typically begin running from the date of diagnosis, not the date of exposure — so time is of the essence after any asbestos-related diagnosis.