Casmalia Resources

Description and History

Site Description

The Casmalia Resources Superfund Site (Site), formerly the Casmalia Resources Hazardous Waste Management Facility, is an approximately 252-acre, inactive commercial hazardous waste treatment, storage, and disposal facility located in Santa Barbara County, California. This Site is located 10 miles southwest of the City of Santa Maria, 1.2 miles north of the Town of Casmalia, and four miles from the Pacific Ocean.

Site History

Between 1973 and 1989, the Site accepted approximately 5.6 billion pounds of waste into 92 waste management or treatment facilities. These facilities included landfills, ponds, shallow wells, disposal trenches, and hazardous waste treatment units. During its operational history, more than 10,000 businesses and government entities sent commercial hazardous waste to the Site. The waste material accepted at the Site included sludges, pesticides, solvents, acids, metals, caustics, cyanide, and nonliquid polychlorinated biphenyls (PCBs). The facility owners and operators were Casmalia Resources, Hunter Resources and Kenneth H. Hunter, Jr.

Facing multiple regulatory enforcement actions, the facility's owners and operators stopped accepting shipments of waste material in 1989. In 1991, the owners and operators abandoned any further efforts to properly close and clean up the Site. At that time, conditions at the Site presented imminent and substantial endangerment to human health and the environment. From 1992 to 1996, the United States Environmental Protection Agency (EPA) used Superfund authorities to take emergency actions to stabilize the various waste management or treatment facilities on the Site. These actions included installing and operating systems for collecting, treating, and disposing of contaminated subsurface liquids, controlling the flow of storm water, and stabilizing the landfills.

Images Documents

Figure 1 - Aerial View Showing Location of Casmalia Resources Disposal Site - JPG
Figure 2 - Aerial View of Site - GIF
Additional Photos Casmalia Site - JPG

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Contaminants and Risks

Wastes found at the Casmalia Resources Superfund Site have include material with toxic properties. However, cleanup actions at the Site are designed to stabilize and provide long-term containment in perpetuity. Waste products generated from ongoing, interim operations (e.g., contaminated groundwater extraction) are being contained and treated on-site or shipped off-site for treatment and disposal.

Although there were historical releases of contaminants to the air during active commercial landfill operations, operations have long since been discontinued and the landfills have been capped or are otherwise being controlled. In addition, older environmental systems that might have been vulnerable to releases have been upgraded or replaced, and EPA has been performing or overseeing continuous improvements to site operations, maintenance, and monitoring practices. Any further contaminant releases to the air are considered unlikely. Without a complete chemical exposure pathway, human health exposure from Site–related contaminants is considered to be negligible. However, a comprehensive human health risk assessment, which examines likely exposure scenarios from Site contaminants, is currently being prepared as part of the draft Remedial Investigation report.

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Who is Involved

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Investigation and Cleanup Activities

In 1996, EPA entered into a judicial settlement (consent decree) with the Casmalia Steering Committee (“CSC”), a group of 54 of the largest generators of waste disposed at the Site. The CSC members generated approximately half of the waste disposed of at the site. The consent decree specifies four phases of work:

• Phase 1 -- Site maintenance, groundwater monitoring, and contaminated liquids management activities for specified periods of time, construction of the pesticides/solvents landfill cap, the planning and design of three additional landfill caps, conducting site investigations, and design of permanent site-wide response actions;
• Phase 2 -- continuation of site maintenance, groundwater monitoring and liquids management activities after Phase 1, construction of the four additional landfill caps, construction of additional permanent site-wide response actions, and five years of operation and maintenance of the permanent responses;
• Phase 3 -- thirty years of Site operation and maintenance and;
• Phase 4 -- the long-term maintenance of the Site once after the 30-year operation and maintenance period is over.

For more details about the site clean-up plans, you may contact one of the EPA’s Remedial Project Manager listed below.

See Site Description and History above.

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Cleanup Results to Date

Landfill Final Covers Installed
A landfill cover (also known as a cap) is designed to provide long-term protection for people and the environment from direct exposure to the hazardous waste contained beneath it. The cap also provides a hydraulic barrier to rainfall, preventing it from leaching through buried hazardous waste and generating additional groundwater contamination --thereby reducing long-term site maintenance costs. A multi-layered landfill cover has been installed on three of the four landfills.

Pesticides/ Solvent Landfill

During the summer of 1999, the CSC constructed a cover system over the Pesticides/Solvents Landfill and a storm water run-off control system. Following construction, EPA deemed that both the cover system and the run-off control system had construction deficiencies and corrective action was necessary. Corrective action work began during summer 2001 and was completed in January 2002.

Heavy Metals and Caustic Cyanide Landfills

In cooperation with EPA and the State of California, the CSC constructed the final cover systems for the Heavy Metals Landfill in 2001 and the Caustic/Cyanide Landfill and Acids Landfill in 2002.

PCB Landfill

The PCB Landfill will be used to contain any contaminated soils and sediments from other portions of the Site during the final phase of response activities; therefore, the PCB Landfill will receive its cover following the completion of these activities.

Surface and Groundwater Monitoring and Treatment Programs Continue

In early 2001, the CSC issued a report regarding site-wide groundwater contamination. The EPA and CSC are continuing their extensive groundwater monitoring program. The goals of this program are to monitor the extent of groundwater contamination and the progress of the on-going site groundwater extraction and treatment system.

Approximately 255 wells are checked for water level elevations on a routine basis. In addition, water from 66 groundwater wells and 5 ponds is sampled annually or semi-annually and analyzed in an environmental laboratory for various chemical contaminants. Chemically affected ground water is treated on-site.

The groundwater treatment system uses granular activated carbon (GAC) to remove organic contaminants from the groundwater collected in the Perimeter Source Control Trenches. Treated water is discharged to an on-site pond for evaporation. Two wells, Gallery Well and Sump 9B, collect contaminated liquids from the Pesticide/Solvent Landfill (PS Landfill). The Gallery Well and Sump 9B liquids are pumped into a holding tank and transferred to a tank truck for transport to an off-site treatment and disposal facility.

Initiation of Site-Wide Investigation and Study: Remedial Investigation/Feasibility Study

The CSC is conducting a comprehensive remedial investigation and study on the nature and extent of Site-related contamination. Information from this investigation and study will be part of a report called a Remedial Investigation/Feasibility Study (RI/FS). For the most recent published information on the RI/FS investigation and study, please follow the link below to the 2006 fact sheet called "Remedial Investigation Updates."

Ongoing remedial investigative (RI) work in 2006 and 2007 included continued data collection and analysis as well as the development of a groundwater flow computer model for the site. The MODFLOW model uses sophisticated computer programs to simulate actual site hydrologic conditions. After proper set-up and calibration have been achieved, the model will provide valuable information to help characterize current groundwater conditions, assess potential future clean-up alternatives and help design future response actions.

EPA and the CSC conducted a detailed geophysical investigation to characterize the subsurface structure of the Site, particularly the P/S Landfill. In December 2005, the CSC undertook extensive geophysical fieldwork under EPA oversight. The geophysics field work and follow-up analysis apply a technology called seismic refraction technology with tomographic inversion. Seismic refraction uses sound waves to assess underground geologic features. EPA has worked with the CSC to complete the evaluation of the geophysical models and analyses and incorporate the results into the Draft RI Report.

EPA approved the final RI Report form the CSC on April 26, 2011.

EPA and the CSC began discussions to identify potential remedial actions for the Site. As part of the FS process, EPA and the CSC will identify and screen environmental technologies and remedial actions that could be suitable for Site cleanup. Remedial alternatives will then be evaluated according to 9 criteria set out in the National Contingency Plan (NCP) pursuant to CERCLA that address protection of human health and the environment as well as overall effectiveness, implementability, and long term and short term costs.

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Potentially Responsible Parties

Potentially responsible parties (PRPs) refers to companies that are potentially responsible for generating, transporting, or disposing of the hazardous waste found at the site.

Financing the Cleanup

In 1992 EPA assumed the role of the lead regulatory agency after the facility's owners and operators claimed financial difficulty and abandoned any further efforts to clean up the Site. EPA responded by undertaking emergency response action activities, while concurrently seeking voluntary participation in site work by former customers of the facility. To clean up, close and care for this site, EPA estimates it will cost $284 million (in 1999 dollars). Sources of funding for these response actions include the trust fund established by the former owners and operators, as well as settlements with “potentially responsible parties” (explained below) and government funding.

Potentially Responsible Parties

Potentially responsible parties (PRPs) refers to people, organizations and companies that are potentially responsible for generating, transporting, or disposing of the hazardous waste found at the site. The PRPs at the Casmalia Site include the former owners and operators and generators and transporters of waste disposed of at the Site.

During the years of the Casmalia facility’s operation, the facility accepted waste from thousands of private businesses and government agencies. One of the EPA’s major responsibilities is to create an equitable process to ensure that each of these parties pays its share of total site costs -- both for the expenses that EPA has incurred already, and for future improvements and maintenance at the site. The current estimate of these expenses is $284 million (1999 Cost Estimate).

To date EPA has settled with over 1,150 Casmalia PRPs EPA refers to these as "Cashout" settlements, because under the settlement terms the PRPs pay into an account to finance the work. Over 1,000 of these entities are referred to as de minimis contributors because they sent relatively small amounts of waste to the Site. The remaining parties include the former owners and operators and customers that are referred to as “major” waste generators. These settlements have generated over $110 million in funding for response actions at the Site.


On September 5, 2000, the EPA settled with 430 of these entities, making approximately $26.1 million in settlement proceeds available for work at the site.

In December of 2001, the EPA also negotiated a settlement with the State of California regarding the State's liability for wastes that the various State departments and agencies shipped to Casmalia. The settlement with the State was for $15.9 million.

On September 29, 2003, a group of 24 additional de minimis Casmalia customers settled with the EPA. These parties sent 1.6% of the waste to the site, and they settled for a total of $8.2 million dollars.

On July 22, 2003, the U.S. District Court for the Central District of California approved a settlement with a group of 41 major waste generators and on August 14, 2003, the same court approved settlements with 3 additional major parties. These 44 parties sent a combined total of 10.9% of the waste to the site, and paid a combined total of $31.8 million.

Naturally, the former owners and operators are expected to apply their own resources to the site’s cleanup as well. To that end, in 1997 the United States filed suit in federal district court against Casmalia Resources, Hunter Resources, and Kenneth H. Hunter, Jr., the facility owners and operators. On February 14, 2002, the owner/operators settled with the EPA for $6.9 million, and the court entered the settlement on November 22, 2002. In May of 2005, the EPA negotiated two settlements with trustees for the estates of George and Mario Castagnola's who were Limited Partners of Casmalia Resources. The settlement was for $400,000.

In September 2004, the EPA settled with 192 more de minimis parties, who paid a total of $11.9 million.

In April 2006, the EPA settled with another 257 de minimis parties for $4.3 million, and finalized settlements with 26 additional de minimis parties that had previously received offers, raising another $1.8 million.

In 2009, EPA settled with 150 de minimis parties in two settlements that raised another $3.9 million.

Funds received from these settlements will be applied to work at the site.

The EPA will continue to offer "Cashout" settlements to PRPs at Casmalia.

Anyone who would like documents associated with the settlement process may download a Document Order Form by clicking the link below called Settlement Documents and fax it to Karen Goldberg's attention at (415) 947-3570, or call (415) 369-0559, extension 10 to request copies.

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Community Involvement

Public Meetings: The EPA is committed to having the local community involved in the issues surrounding the Casmalia site.

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Public Information Repositories

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Additional Links

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