Superfund Sites in Reuse in California
If you are having trouble viewing the map in your browser, click the 'View larger map' link below
ADVANCED MICRO DEVICES, INC.
The Advanced Micro Devices, Inc. Superfund site (AMD) covers 6 acres in Sunnyvale, California. The AMD site is part of the Triple Site, which also includes the nearby TRW Microwave, Inc Superfund site and the Signetics, Inc. site. The three sites contributed to groundwater contamination in the north adjacent area known as the Offsite Operable Unit (OU). Advanced Micro Devices, Inc. designed and made semiconductor devices at two buildings on-site from 1969 to 1992. Two below-ground acid neutralization system tank vaults were located at the northern and southern ends of the 901 and 902 Thompson Place buildings, respectively. Leaks from these tanks appear to be the primary on-site source of volatile organic compounds to groundwater in this area. The two tanks were removed in 1983 and 1984. Impacted soil was excavated and transported to a disposal facility. Facility operations contaminated soil and groundwater with volatile organic compounds, primarily trichloroethylene (TCE). EPA added the AMD site to the National Priorities List in 1986. EPA selected the long-term remedy for the site in the 1991 Record of Decision, together with the TRW Microwave Inc. and Signetics Inc. sites, and the Offsite Operable Unit. AMD removed soil contamination and treated contaminated groundwater. A groundwater extraction and treatment system was installed and operated from 1983-2002, followed by an in-situ bioremediation (ISB) pilot study from 2002-2005. A developer bought the site property in 2006, demolished the former AMD buildings and built a public self-storage facility in 2007. Several other commercial businesses are also on-site; they are not located above groundwater impacted with TCE contamination attributable to the AMD release. Groundwater treatment and monitoring are ongoing. Vapor intrusion assessments at the self-storage facility did not show any evidence of vapor intrusion above screening levels aimed to protect public health.
Last updated October 2025
As of December 2024, EPA had data on 18 on-site businesses. These businesses employed 216 people and generated an estimated $49,464,650 in annual sales revenue. For additional information click here.
For more information:
AMCO CHEMICAL
The 1-acre AMCO Chemical Superfund site is in Oakland, California. From the 1960s to 1989, AMCO Chemical Corporation owned and operated a chemical distribution facility on-site. AMCO demolished several buildings and removed storage tanks and drums from the site during its operations. In 1995, PG&E and the California Department of Transportation found contaminants in soil, soil gas and groundwater near the site. In 1997 and 1998, EPA excavated contaminated soils and operated treatment systems to address immediate threats from groundwater and soil gas contamination. EPA added the site to the National Priorities List in 2003. EPA’s Superfund Redevelopment Program supported reuse planning activities at the site in 2009. Community meetings held as part of the reuse assessment planning process identified local reuse goals for the area. These goals help inform EPA’s remedy selection process. Cleanup goals included groundwater treatment, removal of contaminated soil and vapor intrusion mitigation systems to prevent contaminated vapors from entering buildings. In 2014, local artists and businesses began subleasing a warehouse on-site for commercial and industrial uses. Past site uses include a scrap yard and a cable storage company. In 2017, EPA completed a non-time critical removal action using thermal heating to clean up soil and groundwater. In 2019, the agency initiated a treatability study using in-situ chemical oxidation to determine if the technology could clean up contaminants under the warehouse. EPA is working on a human health risk assessment and feasibility study as part of selecting the site’s long-term remedy.
Last updated October 2025
As of December 2024, EPA did not have economic data related to on-site businesses, or economic data were not applicable due to site use. For additional information click here.
For more information:
- Planning for the Future: Reuse Assessment for the AMCO Chemical Superfund Site (PDF)
- Superfund Site Profile Page
APPLIED MATERIALS
The Applied Materials Superfund site is in Santa Clara, California. A large industrial building occupies most of the 9-acre area. Applied Materials began making semiconductor wafers in the building in 1974. Sampling found soil and groundwater contamination in 1983. Leaking pipes connected to underground tanks may have resulted in the contamination. Applied Materials put in a system to pump and treat contaminated groundwater in 1984. The company also removed underground storage tanks and nearby soil in 1985. EPA added the site to the National Priorities List in 1987. The groundwater treatment system ran until 2002. Groundwater monitoring is ongoing. Applied Materials ended its research and manufacturing activities on-site in 2003. Applied Materials then converted the building into offices and education facilities. Its corporate headquarters are now on-site.
Last updated October 2025
As of December 2024, EPA had data on one on-site business. EPA did not have further economic details related to this business. For additional information click here.
For more information:
ARGONAUT MINE
The Argonaut Mine Superfund site is in Jackson, California. A gold mine was active on-site from the 1850s to 1942. The Argonaut Mining Company owned about 330 acres of land northwest of downtown Jackson. The property sold after the mine closed; about 90 acres of this area are now neighborhoods. The site consists of areas of contamination resulting from the release of hazardous substances from mining operations. EPA has taken several short-term cleanup actions to prevent people’s exposure to mine waste. These actions included removing soil from several areas, including residential yards, a vacant lot, a playing field and a lunch area at a junior high school, and around the main mine shaft. They also included covering an exposed slope with concrete to prevent dirt from leaving the area. EPA added the site to the National Priorities List in 2016. Cleanup activities and investigations are ongoing. In 2022 and 2023, EPA led the cleanup of a major tailings area next to Hoffman Street and Argonaut Lane. This cleanup area has been planted with grass and, in some areas, native oak trees. Continued uses at the site include the junior high school and athletic fields, residential and agricultural areas, and wetlands.
Last updated October 2025
As of December 2024, EPA did not have economic data related to on-site businesses, or economic data were not applicable due to site use. For additional information click here.
For more information:
CELTOR CHEMICAL WORKS
The 26-acre Celtor Chemical Works Superfund Site is located on the Hoopa Valley Indian Reservation in Humboldt County, CA. The Site is heavily used by community members for a variety of traditional and recreational activities including fishing, gathering willows and cooking rocks, picnicking, swimming, camping, and OHV riding. From 1960 to 1962, the Celtor Chemical Works company operated a mill at the Site to process sulfide ore from the nearby Copper Bluff Mine to extract copper and zinc. The mill sluiced tailings down from the former mill area through a drainage ditch into impoundment ponds adjacent to the river. Fish kills were reported, and the Site was added to the National Priorities List in 1983. Wastes from the milling operations and processed ore generated acidic runoff and elevated metals concentrations in soils across the site. EPA completed an interim cleanup action in 1983 that involved excavation of 1,400 cubic yards of contaminated material. In 1985, EPA selected the long-term remedy for the Site. In 1988, EPA completed the remedy and dug up 1,200 more cubic yards of contaminated material and took the material off-site for disposal at an approved hazardous waste disposal facility. The Site was removed from the NPL in 2003. In 2016, additional tailings were discovered at the site. This prompted a new investigation into potential contamination that has been ongoing since 2017. From 2017 to 2022 EPA collected over 500 soil samples across the Site to better understand the nature and extent of contamination. As the river eroded over time, additional mine waste that was previously buried was revealed. This waste presented a human health risk to community members that use the gravel bar. To address this human health risk, EPA completed another cleanup action in 2023. EPA excavated about 2,500 tons of contaminated material and disposed of it off-site in a regulated landfill. Although the most significant human health risks at the site have been addressed, some contamination remains at the Site buried below the surface. Because there is no way for people to currently be exposed to this material, there is no human health risk at the Site. EPA continues to monitor the Site each year to ensure that no one is exposed to this material. The site can now safely be used for a variety of recreational and traditional uses by the Hoopa Valley Tribe.
Last updated October 2025
As of December 2024, EPA did not have economic data related to on-site businesses, or economic data were not applicable due to site use. For additional information click here.
For more information:
COALINGA ASBESTOS MINE
The 120-acre Coalinga Asbestos Mine Superfund site is in Fresno County, California. It consists of two operable units: the Johns-Manville Mill OU and the city of Coalinga OU. The JMM OU includes a former asbestos mine, a former processing mill and associated support buildings, and asbestos tailings. The city OU is also part of the neighboring Atlas Asbestos Mine Superfund site. An asbestos mining, processing and milling facility was on-site from 1959 to 1974. A chromite mill was on-site from 1975 to 1981. Facility operations contaminated air, soils, sediments and surface water. EPA added the site to the National Priorities List in 1983. Federal and potentially responsible party actions addressed the cleanup. Cleanup activities included excavation and disposal of contaminated soils and wastes, regrading of dug-up areas, stream diversion and enhanced creek sediment trapping. Wastes generated during the mining operations were also put in an underground waste management unit and capped with an impermeable cover. EPA took the site off the NPL in 1998. The city OU is in continued commercial, industrial, public service and residential use. Reuses at the city OU include stores, restaurants, social services, medical offices and residential areas.
Last updated October 2025
As of December 2024, EPA had data on 25 on-site businesses. These businesses employed 247 people and generated an estimated $31,632,860 in annual sales revenue. For additional information click here.
For more information:
DEL AMO
The 280-acre Del Amo Superfund site is in Los Angeles, California, in an area known as the Harbor Gateway. The Del Amo synthetic rubber plant was on-site from 1943 to 1972. Manufacturing created various sludge wastes and wastewaters. Some of these wastes went into unlined pits and evaporation ponds. The operations also resulted in releases of contaminants into the soil. Developers turned most of the site into an industrial park in the 1970s. In 1981, the state required the cleanup of soil from one of the waste pits. EPA added the site to the National Priorities List in 2002. Cleanup has included waste pit capping, removal of contaminated vapors from soil beneath the waste pits, and removal of contaminated soils. Biodegradation and groundwater extraction and treatment will address the benzene contamination in groundwater. Developers subdivided 90% of the site property into 83 separate parcels. Developers developed a commercial and industrial business park on the parcels. Facilities include warehouses, freight and manufacturing areas, and office space. High-voltage power transmission lines owned by the Los Angeles Department of Water and Power cross the area. Since 2019, EPA evaluated vapor intrusion and eleven commercial buildings on-site and determined that there is no evidence of vapor intrusion at the eleven commercial buildings. A soil vapor extraction system was installed in one of the on-site properties in 2023, making progress on the site’s cleanup goals. As of March 2025, 46 acres (roughly 16%) of the site have been successfully remediated and deleted from the NPL. Cleanup of groundwater, waste pits and soil outside of this completed area is ongoing.
Last updated October 2025
As of December 2024, EPA had data on 157 on-site businesses. These businesses employed 4,332 people and generated an estimated $1,352,271,365 in annual sales revenue. For additional information click here.
For more information:
- Reuse and the Benefit to Community: Del Amo Superfund Site (PDF)
- Cleanup, Continued Use and Redevelopment in a Thriving Business Park: The Del Amo Superfund Site in Los Angeles, California (PDF)
- Superfund Site Profile Page
DEL NORTE PESTICIDE STORAGE
The 1-acre Del Norte Pesticide Storage Superfund site is located at 2650 West Washington Boulevard in Crescent City, California. From 1970 to 1981, Del Norte County ran a temporary pesticide storage area at the site. It accepted containers from local agricultural industries. Operators at the facility sent contaminated waste and rinse water into an unlined basin on-site. Contaminated shallow groundwater threatened homes, farmland and private wells near the site. In 1984, EPA added the site to the National Priorities List. The agency removed contaminated soils and put in a water treatment system in 1989. The system removed about 95% of the contamination during its first four years of operation. It stopped the spread of the last remaining contaminant by 2002. EPA took the site off the NPL in 2002. In 2020, EPA found that the groundwater meets the agency’s drinking water attainment standards. As a result, in 2023, EPA made an Unlimited Use/Unrestricted Exposure (UU/UE) decision for the site and is working with the State of California Department of Toxic Substances Control on removing land use restrictions.
Last updated October 2025
As of December 2024, EPA had data on one on-site business. This business employed 6 people. For additional information click here. For additional information click here.
For more information:
FAIRCHILD SEMICONDUCTOR CORP. (MOUNTAIN VIEW PLANT)
The Middlefield-Ellis-Whisman Superfund Study Area is in Mountain View, California. The MEW Study Area includes three National Priorities List sites: the Fairchild Semiconductor Corp. (Mountain View Plant) Superfund site, the Intel Corp. (Mountain View Plant) Superfund site and the Raytheon Company Superfund site. Several other facilities and parts of the Naval Air Station Moffett Field federal facility Superfund site are also part of the MEW Study Area. From the 1960s to 1980s, several facilities, including semiconductor, electronics manufacturing, and metal finishing companies, operated in the MEW area. These facilities used solvents, primarily trichloroethene, which were released to the subsurface during operations, handling, and from leaks in tanks and piping. In 1989, EPA selected a cleanup remedy to address facility-specific soil and groundwater source areas and regional groundwater contamination across the MEW Study Area. EPA added the Fairchild Semiconductor Corp – Mountain View Plant site to the NPL in 1991. The soil remedy included excavation of contaminated soil and soil vapor extraction and treatment. Soil cleanup finished in 2001. The groundwater remedy includes slurry walls - barriers beneath the surface to contain contaminants, and extraction and treatment systems to contain and clean up groundwater contamination. In 2010, EPA selected a remedy to address the subsurface to indoor air pathway (vapor intrusion) for existing buildings and new buildings in the vapor intrusion study area. Groundwater treatment and monitoring and vapor intrusion monitoring and mitigation are ongoing. New residential and commercial office developments have been built with vapor intrusion control systems. Most of the Fairchild Semiconductor Corp. (Mountain View Plant) site properties that hosted large commercial office complexes have been unoccupied since 2020. There are some office buildings and small businesses that operate throughout the MEW Study Area.
Last updated October 2025
As of December 2024, EPA had data on one on-site business. This business employed 1,000 people and generated an estimated $1,684,332,226 in annual sales revenue. For additional information click here.
For more information:
FAIRCHILD SEMICONDUCTOR CORP. (SOUTH SAN JOSE PLANT)
The 22-acre Fairchild Semiconductor Corp. (South San Jose Plant) Superfund site is in San Jose, California. A semiconductor manufacturing facility was on-site from 1977 to 1983. Its operations required the use and storage of industrial solvents. Schlumberger Technology Corporation acquired Fairchild Semiconductor Corp. in 1979. Two years later, STC found an underground waste storage tank of organic solvents had failed, resulting in soil and groundwater contamination. The company took many actions to clean up soil and groundwater. EPA added the site to the National Priorities List in 1989. Cleanup included removal of the underground storage tank and contaminated soil, decommissioning of downgradient private water wells, groundwater extraction and treatment, installation of a soil vapor extraction system, soil flushing in the source areas, implementation of groundwater use restrictions and construction of a slurry wall around the perimeter of the property to minimize off-property migration. With approval from the State of California Regional Water Quality Control Board – San Francisco Bay Region, soil flushing ceased in 1991, soil vapor extraction ceased in 1995 and the groundwater treatment system shut down in 1998. Vapor intrusion assessments in 2018 found no evidence of unacceptable vapor intrusion. STC continues to monitor groundwater conditions over time. The site was vacant from 1983 to 1998. From 1998 to 2000, developers built the Bernal Plaza shopping center at the site. It includes a variety of commercial businesses, including a grocery store and restaurants, a vision center, dental practice, a service station and a parking lot. In 2023, the service station, which is within the slurry wall footprint, installed electric vehicle charging stations in its parking lot. The charging stations use fuel cells to generate electricity from hydrogen, offering a clean and efficient alternative to traditional grid-based electric vehicle charging stations.
Last updated October 2025
As of December 2024, EPA had data on 30 on-site businesses. These businesses employed 393 people and generated an estimated $85,927,470 in annual sales revenue. For additional information click here.
For more information:
FRONTIER FERTILIZER
The 8-acre Frontier Fertilizer Superfund site is in Davis, California, next to a freeway and a shopping center. Operations on-site in the 1970s and 1980s included pesticide and herbicide storage, mixing and delivery. They resulted in contaminated soil and groundwater. The California Department of Toxic Substances Control put in a groundwater extraction and treatment system in 1993. EPA added the area to the National Priorities List in 1994. In 1999, EPA’s Superfund Redevelopment Program provided funding to the city of Davis to develop a reuse plan for the site. The plan, finished in July 2001, identified three reuse alternatives: light industrial uses, an office park, and combined light industrial and public uses. Energy production is present on site. EPA first installed solar panels at the site in 2007. The panels reduced the amount of electricity needed to run the groundwater treatment system. After expansion of the solar field in 2010, the solar panels provided 100% of the power for the groundwater extraction and treatment system. The generation of solar energy on-site significantly reduces treatment system energy costs and eliminates about 50 metric tons per year of greenhouse gas emissions. In 2017, more wells were put in to enhance groundwater capture and treatment, and the capacity of the treatment system doubled. In 2019, EPA decided that site soils would not need a cap because they met cleanup standards.
Last updated October 2025
As of December 2024, EPA did not have economic data related to on-site businesses, or economic data were not applicable due to site use. For additional information click here. For additional information click here.
For more information:
FRESNO MUNICIPAL SANITARY LANDFILL
The 145-acre Fresno Municipal Sanitary Landfill Superfund site is 4 miles from Fresno, California. It is a national historic landmark. The prototype for the modern sanitary landfill in the United States was on-site. The city of Fresno opened the municipal landfill in 1935. In 1983, the California Department of Health Services found that methane gas and vinyl chloride gas had traveled from the landfill to surrounding areas. Testing also found that contaminated groundwater had affected several residential wells next to the site. The landfill stopped receiving waste in 1987. EPA added the site to the National Priorities List in 1989. In 1990 and 1991, the city removed contaminated landfill gas. It also capped the landfill, put landfill gas control and surface water management systems in place, and built a groundwater treatment facility. These systems remain active. In 2001, the city redeveloped part of the site into the Fresno Regional Sports Complex. The facility includes soccer and softball fields, restrooms and a playground.
Last updated October 2025
As of December 2024, EPA did not have economic data related to on-site businesses, or economic data were not applicable due to site use. For additional information click here. For additional information click here.
For more information:
HEWLETT-PACKARD (620-640 PAGE MILL ROAD)
The Hewlett-Packard (620-640 Page Mill Road) Superfund site is in Palo Alto, California. Hewlett-Packard made optoelectronic equipment at the 10-acre area from 1962 to 1986. In 1981, at least 300 gallons of waste solvents leaked from an underground storage tank. The primary contaminants of concern are trichloroethene, 1,1-dichloroethene, and tetrachloroethene. The company took out the tank and about 100 cubic yards of contaminated soil in 1981. After manufacturing operations ended in 1986, HP built an office building on-site in 1992. HP sold the property in May 2007. A law firm and several other businesses are now in the building. EPA added the site to the National Priorities List in 1990. Since 1982, groundwater extraction and treatment systems and soil vapor extraction and treatment systems have removed various volatile organic compounds, including trichloroethylene. Other cleanup activities included soil removal and disposal. EPA issued a Record of Decision in 1995 requiring the expansion of the existing groundwater and soil vapor extraction and treatment systems, long-term groundwater monitoring, and a deed restriction for the property. The soil vapor extraction and treatment system operated until 1997 when it was shut down due to rising groundwater elevations. The groundwater extraction and treatment system was shut off in 2022 to allow for an enhanced in-situ bioremediation pilot study on the property. Vapor intrusion studies were conducted in the vapor intrusion study area in 2014 and 2015. The San Francisco Bay Regional Quality Control Board issued a No Further Action on Vapor Intrusion letter in 2016.
Last updated October 2025
As of December 2024, EPA had data on 2 on-site businesses. These businesses employed 1,108 people and generated an estimated $390,781,610 in annual sales revenue. For additional information click here. For additional information click here.
For more information:
INTEL CORP. (MOUNTAIN VIEW PLANT)
The Middlefield-Ellis-Whisman Superfund Study Area is in Mountain View, California. The MEW Study Area includes three National Priorities List sites: the Intel Corp. (Mountain View Plant) Superfund site, the Fairchild Semiconductor Corp. (Mountain View Plant) Superfund site and the Raytheon Company Superfund site. Several other facilities and parts of the Naval Air Station Moffett Field federal facility Superfund site are also part of the MEW Study Area. From the 1960s to 1980s, several facilities, including semiconductor, electronics manufacturing, and metal finishing companies, operated in the MEW area. These facilities used solvents, primarily trichloroethene, which were released to the subsurface during operations, handling, and from leaks in tanks and piping. EPA added the Intel Corp. (Mountain View Plant) site to the NPL in 1986. In 1989, EPA selected a cleanup remedy to address facility-specific soil and groundwater source areas and regional groundwater contamination across the MEW Study Area. The soil remedy included excavating contaminated soil and soil vapor extraction and treatment. Soil cleanup finished in 2001. The groundwater cleanup remedy includes groundwater extraction and treatment systems to control and clean up groundwater contamination. In 2010, EPA selected a remedy to address the subsurface to indoor air pathway (vapor intrusion) for existing buildings and new buildings in the vapor intrusion study area. Groundwater treatment and monitoring and vapor intrusion monitoring and mitigation are ongoing. New residential and commercial office developments have been built with vapor intrusion control systems. Redevelopment is planned for the Intel Corp. (Mountain View Plant) site properties.
Last updated October 2025
As of December 2024, EPA had data on one on-site business. EPA did not have further economic details related to this business. For additional information click here.
For more information:
INTEL CORP. (SANTA CLARA III)
The 4-acre Intel Corp. (Santa Clara III) site is in Santa Clara, California. From 1976 to 2008, the Intel Corporation used the area for quality control testing of chemicals and electrical testing of semiconductors. Facility operations contaminated site groundwater with volatile organic compounds. The source of contamination has not been identified. Spills near the above ground solvent storage facility, leaks from an acid waste neutralization area and solvent spills associated with cleaning out pipes used during construction have been identified as potential sources. In 1982, the San Francisco Bay Regional Water Quality Control Board found groundwater contamination as part of a leak detection program. EPA added the site to the National Priorities List in 1986. In 1990, EPA selected the site’s remedy. Cleanup activities included pumping and treating groundwater, discharging treated groundwater to surface water, groundwater monitoring and deed restrictions to restrict land and water use. In 2010, EPA updated the remedy, replacing most of the original remedy components with monitored natural attenuation. After cleanup finished, EPA took the site off the NPL in 2019. In 2010, Vantage Data Centers purchased the site property. The company built a data storage center on-site. There are also parking areas on-site.
Last updated October 2025
As of December 2024, EPA had data on one on-site business. EPA did not have further economic details related to this business. For additional information click here.
For more information:
INTERSIL INC./SIEMENS COMPONENTS
The 15-acre Intersil Inc./Siemens Components Superfund site is part of a two-property Superfund site in Cupertino and Sunnyvale, California. The Former Intersil, Inc. (Intersil) facility is located at 10900 North Tantau Avenue. The former Siemens Components, Inc. (Siemens) facility is located at 19000 Homestead Road, formerly 10950 North Tantau Avenue. The Off-Property Study Area is north of, and hydraulically downgradient from, the former Intersil and Siemens facilities, which extends into Sunnyvale, California. Calabazas Creek, an intermittent stream, is about 1,500 feet from the site. From 1967 to 1995, Intersil and Siemens Components made semiconductors on-site. In 1980, the California San Francisco Bay Region Regional Water Quality Control Board’s Underground Storage Tank Leak Detection Program found contaminants in soil and groundwater. The SFRWQCB and EPA worked together on the final remedy for the site, which was documented in a final cleanup order in 1990. EPA added the site to the National Priorities List in 1990. From 1990 to the present, the site has been a state-lead NPL site. Past cleanup activities included soil removal and off-site disposal and vapor extraction and treatment of chemical vapors. The soil vapor extraction systems at the sites were discontinued when the systems approached asymptotic conditions (conditions in which diminished decreases of contaminants may be expected) and due to rising groundwater levels. Ongoing cleanup includes groundwater extraction, treatment, monitoring and hydraulic containment of groundwater contaminants. Additionally, four phases of enhanced reductive dichlorination pilot study activities were implemented on the former Siemens property. The Siemens Components building is now in use as offices for a medical facility. The former Intersil building was demolished in 1997. In 2007, a developer purchased the Intersil property and built an office building. The new building was constructed with a vapor barrier to prevent vapor intrusion. The site’s Off Property Study Area is in continued residential use. This area is located over part of the groundwater contamination. Drinking water for Sunnyvale and Cupertino is not affected by the contamination. A vapor intrusion assessment showed no evidence of risk to human health at the site or in the residential area.
Last updated October 2025
As of December 2024, EPA had data on 8 on-site businesses. These businesses employed 30 people and generated an estimated $564,440 in annual sales revenue. For additional information click here.
For more information:
IRON MOUNTAIN MINE
The 4,400-acre Iron Mountain Mine Superfund site is in Shasta County, California. From the 1860s to 1963, mining for copper, gold, pyrite, silver and zinc took place at the site. The site includes former surface and underground mine workings, waste rock piles, tailings piles, abandoned mining facilities and former smelting areas. Acid mine drainage from the site contaminated area surface water, including the Spring Creek Reservoir. EPA added the site to the National Priorities List in 1983. EPA is addressing contamination in six stages. Five long-term cleanup stages are now in progress. They focus on water management and cleaning up major contamination source areas. Acid and metal contamination in surface water has been reduced significantly by capping waste areas, collecting contaminated runoff and treating contaminated surface water. The main mine area is privately owned. Areas around the site include non-residential, privately owned and federally managed lands. The U.S. Bureau of Reclamation manages the Spring Creek Debris Dam area and the Confined Disposal Facility area. There is no public access to the main mine area. A few homes are outside the main mine area. They are not affected by contamination. Water leaving the site ultimately flows into the Upper Sacramento River. Several miles downstream are the intakes for the city of Redding's municipal water supply, which is treated and then serves about 70,000 people. There are no water quality impacts on drinking water. Spring Creek Arm and Lower Keswick Reservoir are public lands used for recreational boating and fishing. A public multi-use rail trail runs along the west bank of the Keswick Reservoir.
Last updated October 2025
As of December 2024, EPA did not have economic data related to on-site businesses, or economic data were not applicable due to site use. For additional information click here.
For more information:
J.H. BAXTER & CO.
The 205-acre J.H. Baxter & Co. Superfund site is in the city of Weed in northern California. J.H. Baxter & Co. and Roseburg Forest Products own the site. Companies have used the site for wood treatment and related activities since 1937. Wood treatment contaminated groundwater, surface water, soil, sludge and a nearby creek. EPA added the site to the National Priorities List in 1989. In the late 1990s, potentially responsible parties fenced off the area to prevent direct contact with contamination. Construction of a slurry wall and extraction well system finished in 1999. The system is expected to operate indefinitely. Site soils have been excavated, treated and capped. A protective asphaltic-concrete surface covers about 14 acres of the site. It prevents direct contact with contaminants. A stormwater management system controls and treats surface water. Institutional controls restricting land and groundwater use are in place. Routine operation and maintenance activities and groundwater treatment and monitoring are ongoing. A lumber mill and veneer plant are on-site. Part of the site is leased for wood-treating operations. Beaughton Creek crosses the eastern part of the site.
Last updated October 2025
As of December 2024, EPA had data on 2 on-site businesses. These businesses employed 9 people and generated an estimated $830,000 in annual sales revenue. For additional information click here.
For more information:
JASCO CHEMICAL CORP.
The 2-acre Jasco Chemical Corp. Superfund site is located in Mountain View, California. JASCO repackaged and formulated chemical products on-site from 1976 to December 1995. The company’s waste disposal practices and leaks from underground storage tanks contaminated soil and groundwater. In addition, volatile organic compounds formed vapors in the soil. EPA added the site to the National Priorities List in 1989. Underground storage tanks with chemicals were removed. Contaminated soil was removed or cleaned up using bioremediation. Groundwater was treated to remove the VOCs. Groundwater monitoring at the Site ended in 2010 as all groundwater contaminants of concern related to the Site met groundwater cleanup standards. After cleanup, EPA took the site off the NPL in 2020. A 266-unit apartment complex and city park was built on top of the former JASCO Site. Construction was completed in 2022, and the apartment complex is now occupied.
Last updated October 2025
As of December 2024, EPA did not have economic data related to on-site businesses, or economic data were not applicable due to site use. For additional information click here. For additional information click here.
For more information:
JERVIS B. WEBB CO.
The Jervis B. Webb Co. Superfund site is in South Gate, California. From the 1950s to early 1996, a business made industrial conveyor belts on the southeast part of the site. A facility made aluminum and stainless-steel aircraft rivets on the northwest part of the site until about 1981. These activities contaminated soil and groundwater. EPA removed some of the contaminated soil and replaced it with clean fill in 1999. The agency added the site to the National Priorities List in 2012. EPA completed the remedial investigation in 2016. After completing a feasibility study in 2023 EPA proposed the use of Situ Thermal Remediation for the site. In situ thermal treatment methods move or “mobilize” harmful chemicals in soil and groundwater using heat. The chemicals that are not destroyed move through soil and groundwater toward wells where they are collected and piped to the ground surface to be treated using other cleanup methods. A towing business and a steel manufacturing company are active on-site.
Last updated October 2025
As of December 2024, EPA had data on 2 on-site businesses. These businesses employed 8 people and generated an estimated $3,663,000 in annual sales revenue. For additional information click here.
For more information:
JIBBOOM JUNKYARD
The 9-acre Jibboom Junkyard Superfund site is in Sacramento, California. The Associated Metals Company ran a metal-salvaging facility on-site from 1950 to 1965. Salvage activities contaminated the area with herbicides, pesticides and volatile organic compounds. The California Department of Transportation bought the property in 1965 to build an elevated freeway. EPA added the site to the National Priorities List in 1983. Cleanup took place from 1985 to 1987. Cleanup included removal and disposal of contaminated soil and backfilling with clean soil. The soil cleanup prevented contamination of groundwater. After cleanup, EPA took the site off the NPL in 1991. Today, U.S. Interstate 5 covers 7 acres of the site. The rest of the site, located between the interstate and the Sacramento River, is home to Robert T. Matsui Waterfront Park. The city of Sacramento started the park design process in 1990. Construction activities finished in 2007. The park includes a walkway that connects a fountain plaza to an overlook on a pier. The park has native vegetation, green space for picnicking and benches with river views. In 2024, the city, in partnership with the Sacramento Tree Foundation, opened a new addition to the park. The Hanami Line includes over 100 cherry blossom trees, public art, drought-tolerant landscaping, seating and an area for hosting festivals.
Last updated October 2025
As of December 2024, EPA did not have economic data related to on-site businesses, or economic data were not applicable due to site use. For additional information click here.
For more information:
LAVA CAP MINE
The 33-acre Lava Cap Mine Superfund site is a former gold mine in the Sierra foothills outside of Nevada City, California. Various entities ran the Lava Cap Mine during two periods. The first period ran from 1860 to 1918. The second period ran from 1934 to 1943. More intensive gold and silver mining took place during the second period, with an average of 300 to 400 tons of ore processed per day. In addition to gold and silver, ore contained naturally occurring arsenic and trace amounts of heavy metals, such as lead. After ore processing, arsenic and heavy metals remained in the finely ground tailings. These improper disposal practices contaminated groundwater, surface water, soil, and sediment on site. EPA added the site to the National Priorities List in 1999. In 2006, the mine buildings were cleaned and fenced, hazardous waste was shipped to an off-site landfill, creeks and other surface waters were lined with an impermeable membrane liner, and a cap was placed over mine tailings in the main mine area. In 2014, EPA connected homes near the former mine to the local public water supply, ensuring that contaminated groundwater beneath the mine could not affect drinking water. Cleanup is ongoing, with a cap completed and design underway for mine drainage treatment. EPA has conducted a remedial investigation study (2017-2022) for the site, which included the installation of new monitoring wells, groundwater sampling, and soil gas sampling. EPA is in the final stages of finalizing the remedial investigation report and is currently planning to conduct additional field work to fill in the data gaps from the initial investigation. After the remedial investigations, EPA will prepare a feasibility study to determine how to clean up groundwater contamination. There are homes on-site. They remain in use during cleanup.
Last updated October 2025
As of December 2024, EPA did not have economic data related to on-site businesses, or economic data were not applicable due to site use. For additional information click here.
For more information:
LOUISIANA-PACIFIC CORP.
The Louisiana-Pacific Corp. Superfund site in Oroville, California, encompasses a 100-acre wood-processing plant and a 115-acre landfill, separated by a half mile. Georgia-Pacific Corporation built the plant in 1969 and operated it until 1973, when Louisiana-Pacific Corporation took over ownership and operation of both the plant and landfill. In 1973, the state detected high levels of contamination in nearby residential wells. By 1983, groundwater contamination had migrated 1.5 miles south of the site. For this reason, the site was added to the National Priorities List (NPL) by EPA in 1986. After listing, EPA installed a fence around the perimeter and imposed deed restrictions on residential use of the site. The cleanup process included soil sampling, and groundwater cleanup involved restrictions on new well permits as well as monitoring on-site wells for contamination. After conducting additional soil and groundwater investigations, EPA determined the site did not require further cleanup and was removed from the NPL in 1996. Louisiana-Pacific Corporation has since closed, and the area is now an industrial park.
Last updated October 2025
As of December 2024, EPA had data on 11 on-site businesses. These businesses employed 62 people and generated an estimated $8,358,680 in annual sales revenue. For additional information click here.
For more information:
MCCOLL
Location: The 22-acre McColl Superfund site is situated in Fullerton, California, approximately 20 miles east of Los Angeles. Historical Background: 1942-1946: The site was used as a disposal area for petroleum refinery waste, where an estimated 72,600 cubic yards of hazardous materials were dumped into 12 pits. This practice led to significant soil and groundwater contamination, posing health risks to nearby residents. Community Concerns: In 1978, residents reported strong odors and health problems, prompting EPA to investigate the site. The site was officially added to the National Priorities List in 1983 due to the severity of the contamination. Remediation Efforts: 1996-1997: Responsible parties undertook remediation measures, which included capping the contaminated pits and installing a gas collection system along with groundwater monitoring equipment. This action was part of a broader effort to mitigate environmental hazards. Community Redevelopment: Based on feedback from the community, the site was transformed into three championship golf holes, which are now part of a larger golf course and country club. The golf course opened in 1998, integrating the previously contaminated area into a recreational space for the public. Current Status: Ongoing remedial investigations for Tert Butly Alcohol (TBA) and maintenance activities are being conducted to ensure the safety and effectiveness of the cleanup efforts.
Last updated October 2025
As of December 2024, EPA had data on one on-site business. EPA did not have further economic details related to this business. For additional information click here. For additional information click here.
For more information:
MEW STUDY AREA
The MEW Study Area is in Mountain View, California. MEW (Middlefield-Ellis-Whisman) includes three National Priorities List sites: the Fairchild Semiconductor Corp. (Mountain View Plant) Superfund site, the Intel Corp. (Mountain View Plant) Superfund site and the Raytheon Company Superfund site. Several other facilities and parts of the Naval Air Station Moffett Field federal facility Superfund site are also part of the MEW Study Area. From the 1960s to 1980s, semiconductor, electronics manufacturing and metal finishing companies operated in the MEW area. These facilities used solvents, primarily trichloroethene, which were released to the subsurface during operations and handling, and from leaks in tanks and piping. In 1989, EPA selected a cleanup remedy to address soil and groundwater contamination across the MEW Study Area. In 2010, EPA selected a remedy to address the subsurface to indoor air pathway (vapor intrusion) for existing buildings and new buildings in the Vapor Intrusion Study Area. Groundwater treatment and monitoring and vapor intrusion monitoring and mitigation are ongoing. New residential and commercial office developments have been built with vapor intrusion control systems. Fairchild Semiconductor Corp. (Mountain View Plant) site properties formerly large office complexes have been mostly vacant since 2020, while other buildings within the MEW Study Area have been returned to commercial office and light industrial use. Redevelopment is planned for the Intel Corp. (Mountain View Plant) site properties, which are currently unoccupied. Raytheon site properties have been sold and the buildings are currently vacant.
Last updated October 2025
As of December 2024, EPA did not have economic data related to on-site businesses, or economic data were not applicable due to site use. For additional information click here.
For more information:
MONTROSE CHEMICAL CORP.
The 18-acre Montrose Chemical Corp. Superfund site is in Los Angeles, California. From 1947 to 1982, pesticide chemicals, including dichloro-diphenyl-trichloroethane, were made on-site. From 1953 to 1971, waste containing DDT from manufacturing operations went into the sanitary sewer collection system operated by the Los Angeles County Sanitation Districts. These contaminants traveled through the sewer system and a pollution control plant and into the Pacific Ocean through an outfall system. EPA investigations found widespread contamination on and around the facility. EPA added the site to the National Priorities List in 1989. To manage the cleanup, EPA divided the site into seven areas, or operable units. In 2009, EPA issued an Interim Record of Decision for OU-5, the Palos Verdes Shelf, to select an interim remedy. It consists of institutional controls, monitored natural recovery, and contamination containment using an outfall area cap. Remedial actions at the site have included groundwater extraction and treatment, electrical resistance heating and soil vapor extraction for dense non-aqueous phase liquid (DNAPL) and institutional controls covering public outreach, education, fish monitoring and enforcement. Other cleanup activities included the excavation of contaminated soil from residential properties in the 1990s, soil sampling and excavation of a neighborhood in 1993, and contaminated sediment removal from the nearby sanitary sewer system from 1996 to 1998. Cleanup, operation and maintenance activities, and monitoring are ongoing. Current cleanup activities include groundwater treatment, electrical resistance heating, soil vapor extraction, monitored natural recovery, and institutional controls. OU-5, the Palos Verdes Shelf, is in continued use for commercial purposes and sport fishing. Parts of OU-5 are also used for boating, swimming, windsurfing, surfing, scuba diving, snorkeling and shell fishing. The California Department of Fish and Wildlife designated two parts of OU-5 as State Marine Conservation Areas with the goal of protecting natural habitats and marine life.
Last updated October 2025
As of December 2024, EPA did not have economic data related to on-site businesses, or economic data were not applicable due to site use. For additional information click here.
For more information:
NATIONAL SEMICONDUCTOR CORP.
The 150-acre National Semiconductor Corp. Superfund site is in Santa Clara and Sunnyvale, California. It shares a groundwater plume with the nearby Monolithic Memories Superfund site. Starting in 1967, National Semiconductor Corp. made electronic equipment at the site. Investigations, which began in 1982, found volatile organic compounds in soil and groundwater. Leaks from underground storage tanks, sumps and pipes were the suspected sources of the contamination. EPA added the site to the National Priorities List in 1987. Under EPA’s oversight, National Semiconductor Corp., the site’s potentially responsible party, removed leaking tanks, sumps and pipes, and treated soil source areas. The PRP began extraction and treatment of contaminated groundwater in 1984. Other cleanup actions included the removal and disposal of contaminated soil and the implementation of pilot and full-scale remedial actions in the various Santa Clara source areas. Remedial actions also included ozone sparging, soil vapor extraction, chemical oxidation and bioremediation. Restrictions were also placed on site groundwater use. By 2005, 13 of the original 14 soil source areas received regulatory closure from the California Regional Water Quality Control Board, San Francisco Bay Region. Cleanup of the final soil source area finished in 2013. Groundwater treatment and monitoring are ongoing. Efforts to evaluate and address vapor intrusion in buildings over the plume are also underway. Mitigation measures are taken wherever necessary to address any unacceptable vapor intrusion. Manufacturing activities at the site ended by 1999. Applied Materials, an on-site business, put in solar panels in 2008. Texas Instruments took over National Semiconductor Corp. in 2011. About 8.6 acres of the site were purchased in 2013 for use as office and commercial space. Texas Instruments’ Santa Clara campus on-site includes design and sales offices, research and development laboratories, and support services.
Last updated October 2025
As of December 2024, EPA had data on 13 on-site businesses. These businesses employed 1,739 people and generated an estimated $881,354,488 in annual sales revenue. For additional information click here.
For more information:
OPERATING INDUSTRIES, INC., LANDFILL
The Operating Industries, Inc., Landfill Superfund site is 10 miles east of Los Angeles in Monterey Park, California. The Pomona Freeway divides the 190-acre area into two parcels – the 145-acre South Parcel and the 45-acre North Parcel. From 1948 to 1984, a landfill was on-site. It received residential and commercial refuse, liquid wastes, and various hazardous wastes and materials. In the 1980s, EPA took emergency actions to begin stabilizing the site. The agency added the site to the National Priorities List in 1986. Cleanup actions included covering the landfill, controlling landfill gas and managing chemicals in water draining from the landfill. A treatment plant collects landfill liquids for treatment. Monitoring and maintenance of the cleanup systems is ongoing. Institutional controls restrict groundwater use and limit reuse on the landfill cap. From 2002 to 2009, six 70-kilowatt microturbines changed landfill gas into electricity on-site. The electricity provided half the energy needed to run the treatment plant, saving the project about $1.75 million over seven years. In 2016, the potentially responsible parties worked with the city of Monterey Park and a developer to redevelop the North Parcel for commercial use. Restaurants and retail businesses opened on-site in 2018. In 2019, EPA’s Region 9 presented its Excellence in Site Reuse Award to the Operating Industries, Inc., Landfill Site Custodial Trust, the city of Monterey Park and M&M Realty Partners. The award is given to developers, site owners, responsible parties and other stakeholders demonstrating excellence in working with EPA on the redevelopment of Superfund sites.
Last updated October 2025
As of December 2024, EPA had data on 13 on-site businesses. These businesses employed 659 people and generated an estimated $148,854,887 in annual sales revenue. For additional information click here.
For more information:
- Superfund Site Profile Page
- Site Redevelopment Profile: Operating Industries Inc. (PDF)
- EPA Region 9 Excellence in Site Reuse Award
- Sites in Reuse: Former Landfill Property (PDF)
PACIFIC COAST PIPELINE
The Pacific Coast Pipeline Superfund site is a 55-acre area located east of the city of Fillmore in Ventura County, California. A petroleum refinery was on-site from about 1915 to 1950. Texaco Inc., now a subsidiary of Chevron Corporation, acquired the refinery in 1928. It shut down in 1950, was largely dismantled by 1951 and converted to a crude oil pumping station by 1952. Improper disposal practices contaminated soil with lead and polycyclic aromatic hydrocarbons and contaminated groundwater with volatile organic compounds. EPA added the site to the National Priorities List in September 1989. In 1992, EPA selected pumping and treatment of contaminated groundwater as the long-term remedy. The responsible party put in two extraction wells and a soil vapor extraction system. The systems reduced the amount of benzene in groundwater but could not clean the groundwater to meet drinking water standards. EPA approved the shutdown of the systems in 2002. In 2011, EPA selected a remedy for contaminated soil and changed the remedy for groundwater. Surface soil cleanup finished in 2014. EPA took the surface soil part of the site off the NPL in 2018. Groundwater concentrations are trending toward site cleanup goals and the groundwater remedy has transitioned to monitored natural attenuation, a process where naturally occurring processes reduce contamination. Institutional controls are in place to restrict land and groundwater use. Infrastructure on-site includes electric utilities that support cleanup activities and solar power facilities. Development of a 3-megawatt solar facility began in 2020. The 11,000-module facility started running in September 2021, delivering an alternate source of electricity to Ventura County residents and businesses.
Last updated October 2025
As of December 2024, EPA had data on one on-site business. EPA did not have further economic details related to this business. For additional information click here.
For more information:
PEMACO MAYWOOD
The 4-acre Pemaco Maywood Superfund site is located along the Los Angeles River in Maywood, California. A chemical mixing facility was on-site from the 1940s to 1991. In 1993, a fire destroyed the plant. EPA identified hazardous chemicals in the soil and groundwater, leading to the site's addition to the National Priorities List in 1999. In 2008, EPA completed the treatment of the most contaminated soils using electrical resistive heating. A carbon-based treatment system for soil vapors and groundwater remains in operation, supported by a solar-powered energy system. The 3.4-kilowatt solar system generates about 5,700 kilowatt hours annually, reducing carbon dioxide emissions by about 3.3 tons each year. The city of Maywood and The Trust for Public Land incorporated the site into a community park as part of the Los Angeles River Greenway project. Maywood Riverfront Park opened in 2006. It includes soccer fields, basketball courts, a play area, native plant landscaping and picnic areas. EPA, in conjunction with the city of Maywood, redeveloped another part of the site as part of the park. This area opened to the public in 2018. It features walkways, lighting, gazebos, benches and barbeques. Today, Maywood Riverfront Park continues to offer much-needed athletic and recreation facilities in a heavily populated urban area. The California Department of Toxic Substances Control is the lead agency for the site.
Last updated October 2025
As of December 2024, EPA did not have economic data related to on-site businesses, or economic data were not applicable due to site use. For additional information click here.
For more information:
RALPH GRAY TRUCKING CO.
The 23-acre Ralph Gray Trucking Co. Superfund site is in Westminster, California. In the 1930s, Murdy Dairy Farm was on-site. Beginning in 1936, Ralph Gray collected acid sludge, oil field wastes and oil refinery wastes and put them in four unlined pits at the farm. Ralph Gray abandoned the disposal pits in the late 1930s. The pits remained undisturbed until the construction of 75 homes in the late 1950s. Before construction, the homebuilders buried hazardous substances from the pits in two unlined trenches that cut through the backyard areas of about 25 lots. Residents reported black sludge and seep material in their yards. EPA added the site to the National Priorities List in 1992. EPA’s removal actions included razing and restoration of backyard improvements, such as house additions, swimming pools, decks, other structures and landscaping. Cleanup and restoration contractors took down several houses and rebuilt them directly above waste deposits. The contractors removed visible material and dug at least 5 more feet into the clean soil. After the removal work, EPA restored affected yards and structures. EPA also provided financial compensation to owners of demolished homes as part of the cleanup effort so that owners could rebuild or replace their homes. EPA completed all restoration work in 1997. EPA took the site off the NPL in 2004. The site is in continued residential use.
Last updated October 2025
As of December 2024, EPA did not have economic data related to on-site businesses, or economic data were not applicable due to site use. For additional information click here.
For more information:
RAYTHEON CORP.
The Middlefield-Ellis-Whisman Superfund Study Area is in Mountain View, California. The MEW Study Area includes three National Priorities List sites: the Raytheon Corp. Superfund site, the Fairchild Semiconductor Corp. (Mountain View Plant) Superfund site and the Intel Corp. (Mountain View Plant) Superfund site. Several other facilities and parts of the Naval Air Station Moffett Field federal facility Superfund site are also part of the MEW Study Area. From the 1960s to 1980s, several facilities, including semiconductor, electronics manufacturing, and metal finishing companies, operated in the MEW area. These facilities used solvents, primarily trichloroethene, which were released to the subsurface during operations, handling and from leaks in tanks and piping. EPA added the Raytheon Superfund site to the NPL in 1986. In 1989, EPA selected a cleanup remedy to address facility-specific soil and groundwater source areas and regional groundwater contamination across the MEW Study Area. The soil remedy included excavating contaminated soil and soil vapor extraction and treatment. Soil cleanup finished in 2001. The groundwater remedy includes slurry walls - barriers beneath the surface to contain contaminants, and extraction and treatment systems to control and clean up groundwater contamination. In 2010, EPA selected a remedy to address the subsurface to indoor air pathway (vapor intrusion) for existing buildings and new buildings in the vapor intrusion study area. Groundwater treatment and monitoring and vapor intrusion monitoring and mitigation are ongoing. New residential and commercial office developments have been built with vapor intrusion control systems. Commercial office buildings are currently unoccupied at the former Raytheon facility properties.
Last updated October 2025
As of December 2024, EPA had data on 2 on-site businesses. These businesses employed 52 people and generated an estimated $8,260,000 in annual sales revenue. For additional information click here.
For more information:
RHONE-POULENC, INC./ZOECON CORP.
The 13-acre Rhone-Poulenc Inc./Zoecon Corp. site is in East Palo Alto, California. It includes a former pesticide manufacturing plant, a sludge pond and a chemical storage facility. From the late 1950s to the early 1970s, workers stored hazardous waste drums on-site. Some of the drums leaked. In 1980, an investigation by new site owners found arsenic contamination in soil and groundwater. EPA proposed adding the site to the National Priorities List in 1984 and removed it from consideration in 1989. The California Department of Health Services led the cleanup, which addressed contaminated soil and groundwater. Most of the site is not in use. Part of the Bay Trail, a 500-mile regional walking and cycling trail around San Francisco Bay, crosses the site.
Last updated October 2025
As of December 2024, EPA did not have economic data related to on-site businesses, or economic data were not applicable due to site use. For additional information click here.
For more information:
ROCKETS, FIREWORKS, AND FLARES SITE
The Rockets, Fireworks, and Flares Superfund site, formerly known as the B.F. Goodrich Superfund site, consists of a 160-acre industrial area in Rialto, California, and a 6-mile-long area of groundwater contamination. In the 1940s, the U.S. Army used part of the site to store ammunition and weapons. Defense contractors and fireworks manufacturers used the land after World War II. Operators handled perchlorate salts and other hazardous chemicals and disposed of chemical wastes on-site. Chemicals seeped into the ground and contaminated the groundwater. The underground water supply is a critical source of drinking water for residents and businesses in Rialto and nearby communities. The California Regional Water Quality Control Board led initial efforts to address the contamination. EPA added the site to the National Priorities List in 2009. The Goodrich Corporation, Emhart Industries (a corporate successor to West Coast Loading Corporation), Pyro Spectaculars, American Promotional Events and others entered into agreements with EPA to pay for the cleanup. With EPA’s oversight, Emhart Industries completed the construction of the first of two groundwater cleanup projects in 2023. EPA finalized its second groundwater cleanup plan in 2022. It includes removing and treating contaminated groundwater, preventing the spread of contaminated groundwater, and making the treated groundwater available as a drinking water source. More soil and groundwater testing is ongoing. Pyro Spectaculars and American Promotional Events remain active on-site. Other industrial businesses remain active on-site as well. They include a concrete pipe manufacturer. The site also includes residential areas above the groundwater plume.
Last updated October 2025
As of December 2024, EPA had data on 4 on-site businesses. These businesses employed 192 people and generated an estimated $20,580,111 in annual sales revenue. For additional information click here.
For more information:
SAN FERNANDO VALLEY (AREA 1)
The San Fernando Valley (Area 1) Superfund site is one of four Superfund sites in California’s San Fernando Valley. The site covers about 20 square miles. It includes the areas of North Hollywood and Burbank. The San Fernando Valley groundwater basin provides drinking water to residents of the cities of Los Angeles, Burbank and Glendale. Decades of aerospace and manufacturing activities in the San Fernando Valley contaminated the groundwater aquifer with chromium and volatile organic compounds. Sampling in 1980 under a statewide effort to identify groundwater contamination found high levels of VOCs in city wells in the area. EPA added the site to the National Priorities List in 1986. The agency oversees the cleanup of contaminated groundwater. Cleanup includes extraction and treatment of contaminated groundwater. Two groundwater pump-and-treat systems have operated in the North Hollywood and Burbank areas since 1989 and 1996, respectively. Treated groundwater from the Burbank groundwater treatment system provides a municipal water source for the community. The treated groundwater saves the municipality millions of dollars every year. This urban area includes residential, commercial and industrial areas. In 2001, part of the site (Lockheed Martin's B-1 area) was redeveloped for commercial uses, called the Burbank Empire Center. In 2005, the Burbank Airport Commerce Center was built on-site; it includes commercial and light industrial uses. Since 1930, Hollywood Burbank Airport has been active on-site.
Last updated October 2025
As of December 2024, EPA had data on 150 on-site businesses. These businesses employed 4,741 people and generated an estimated $952,818,566 in annual sales revenue. For additional information click here.
For more information:
- Reuse and the Benefit to Community: San Fernando Valley (Area 1) Superfund Site: Burbank (PDF)
- Superfund Site Profile Page
SAN FERNANDO VALLEY (AREA 2)
The San Fernando Valley (Area 2) Superfund site is one of four Superfund sites in California’s San Fernando Valley. It covers about 6,680 acres. The San Fernando Valley groundwater basin provides drinking water to residents in Los Angeles, Burbank and Glendale. In 1980, several cities in the San Fernando Valley found contamination in drinking water wells. The chemicals found in wells were used widely by many industries, including aerospace and defense manufacturing, machinery degreasing, dry cleaning and metal plating. EPA added the site to the National Priorities List in 1986. A pump-and-treat system addresses volatile organic compound contamination in the regional groundwater aquifer. The system provides drought-resistant clean drinking water source for Glendale. Remedial designs underway will help the system capture more contamination. EPA is completing reporting on a vapor intrusion assessment from groundwater across Area 2. In 2004, the agency began studying chromium contamination at the site. EPA set up the Glendale Chromium area in 2007 to address chromium contamination in groundwater. In 2022, a draft feasibility study identified cleanup options for chromium. The feasibility study is ongoing, but an ion exchange system is currently in place to remove Chromium contamination in the regional groundwater aquifer. The groundwater treatment plant serves as the existing Glendale South and Glendale North interim remedy. Since the start of operation of the groundwater treatment plant in 2000, an estimated 58 billion gallons of water has been treated with over 83,000 pounds of VOCs and over 800 pounds of Chromium removed. Continued uses at the site include industrial, residential, recreational and commercial areas.
Last updated October 2025
As of December 2024, EPA had data on one on-site business. This business employed 3 people and generated an estimated $710,000 in annual sales revenue. For additional information click here.
For more information:
SAN FERNANDO VALLEY (AREA 4)
The San Fernando Valley (Area 4) Superfund site is one of four Superfund sites in California’s San Fernando Valley. EPA added these sites to the National Priorities List in 1986. Groundwater contamination in the San Fernando Valley came from a range of industrial operations. The San Fernando Valley Groundwater Basin provides treated drinking water to residents of the cities of Los Angeles, Burbank and Glendale and the La Crescenta Water District. The San Fernando Valley (Area 4) Pollock Operable Unit covers about 5,860 acres near the Los Angeles Department of Water and Power Pollock Well Field in Los Angeles. The site is in the southern part of the San Fernando Valley Groundwater Basin south of Los Feliz Boulevard, in an urban area that includes residential, public service, commercial and industrial land uses. After site investigations, EPA determined in 1994 that selecting and implementing a groundwater remedy was not necessary at that time because private water-supply wells are prohibited and LADWP planned to install a facility at its Pollock Well Field to treat contaminated groundwater. In 1999, LADWP reactivated two wells in the Pollock well field and began operating the groundwater treatment facility. Currently, San Fernando Valley (Area 4) groundwater is treated to meet EPA and state drinking water standards before it is transferred to LADWP’s public water supply system. EPA has conducted a remedial investigation study (2017-2022) for the site, which included the installation of new monitoring wells, groundwater sampling, and soil gas sampling. EPA is in the final stages of finalizing the remedial investigation report and is currently planning to conduct additional field work to fill in the data gaps from the initial investigation. After the remedial investigations, EPA will prepare a feasibility study to determine how to clean up groundwater contamination.
Last updated October 2025
As of December 2024, EPA did not have economic data related to on-site businesses, or economic data were not applicable due to site use. For additional information click here.
For more information:
SAN GABRIEL VALLEY (AREA 1)
The San Gabriel Valley (Area 1) Superfund site is one of four San Gabriel Valley Superfund sites in Southern California. These sites include areas of VOC-contaminated groundwater in the 170-square-mile San Gabriel Valley. Decades of improper chemical handling and waste disposal practices at hundreds of industrial sites across the valley resulted in widespread groundwater contamination. Most of the activities that led to the contamination likely occurred between the 1940s and 1970s. Investigations and studies to identify the sources of contamination continue. EPA added the four main areas of groundwater contamination in the San Gabriel Valley to the National Priorities List in 1984. To date, EPA and the State of California have found soil contamination at over 150 potential source facilities within Area 1. The El Monte Operable Unit of Area 1 includes about 3 square miles of groundwater contamination under parts of the cities of El Monte, Rosemead and Temple City, while the South El Monte Operable Unit includes about 8 square miles of groundwater contamination under parts of the cities of South El Monte, El Monte and Rosemead, and the Whitter Narrows Operable Unit includes about 4 square miles of groundwater contamination in the southernmost part of San Gabriel Valley. As part of the regional groundwater remedy for Area 1, EPA continues to oversee the operation of nine groundwater treatment systems. Construction of remedy enhancements to one of the shallow groundwater systems in El Monte was completed in 2024. Water utilities in the area provide clean water that meets all state and federal drinking water standards. Site systems have treated more than 27 billion gallons of contaminated water and removed more than 13,000 pounds of contaminants from the aquifer. Cleanup, monitoring and sampling activities are ongoing as part of the regional groundwater remedy and at former source properties overseen by state lead agencies. Continued site uses include commercial, industrial, residential and open space areas as well as recreation and flood control.
Last updated October 2025
As of December 2024, EPA did not have economic data related to on-site businesses, or economic data were not applicable due to site use. For additional information click here.
For more information:
SAN GABRIEL VALLEY (AREA 2)
The San Gabriel Valley (Area 2) Superfund site is one of four San Gabriel Valley Superfund sites in Southern California. The sites include areas of contaminated groundwater in the 170-square-mile San Gabriel Valley. In 1984, EPA added four areas of groundwater contamination in the valley to the National Priorities List. The Area 2 site (also known as the Baldwin Park Operable Unit) includes groundwater contamination under parts of the cities of Azusa, Irwindale, Baldwin Park, West Covina, La Puente and Industry. It covers about 10 square miles. Land use at the site is largely suburban, with a mix of residential, commercial and industrial areas. Cleanup includes the operation of five large groundwater pump-and-treat systems. They help ensure an adequate supply of clean water for the region. They provide enough treated groundwater to supply over 100,000 homes and businesses. Groundwater treatment began in about 2000. Water agencies test drinking water regularly to make sure it meets state and federal safe drinking water standards. Cleanup, monitoring and sampling activities are ongoing.
Last updated October 2025
As of December 2024, EPA did not have economic data related to on-site businesses, or economic data were not applicable due to site use. For additional information click here.
For more information:
SAN GABRIEL VALLEY (AREA 3)
The San Gabriel Valley (Area 3) Superfund site is one of four San Gabriel Valley Superfund sites in Southern California. In 1979, state-required testing by water providers found multiple areas of contamination in the San Gabriel Valley’s water supply. Hundreds of businesses and companies contaminated over 30 square miles of groundwater in the San Gabriel Valley. Contaminants in the groundwater include volatile organic compounds and industrial solvents. In 1984, EPA added the four main areas of groundwater contamination in the valley to the National Priorities List. The Area 3 site addresses groundwater within a 19-square-mile area underlying the cities of Alhambra, Rosemead, San Gabriel, San Marino, South Pasadena and Temple City. Land uses at the site include commercial and residential areas. There are also some areas of light industry and open space. EPA is investigating the site and preparing for a sitewide feasibility study in 2026. EPA expects to complete investigations and select a cleanup plan for the site in 2027. Water utilities in the area provide clean water that meets all state and federal drinking water standards. Cleanup, monitoring and sampling activities at former source properties that may have contributed to the groundwater are overseen by state-lead agencies.
Last updated October 2025
As of December 2024, EPA did not have economic data related to on-site businesses, or economic data were not applicable due to site use. For additional information click here.
For more information:
SAN GABRIEL VALLEY (AREA 4)
The San Gabriel Valley (Area 4) Superfund site is one of four areas of VOC-contaminated groundwater in the 170-square-mile San Gabriel Valley located in southern California. In 1979, state-required testing by water providers found multiple areas of contaminated with volatile organic compounds (VOCs) in the San Gabriel Valley’s water supply. Hundreds of businesses and companies contributed to the groundwater contamination extending over a 30-square mile area in the San Gabriel Valley. In 1984, EPA added the four main areas of VOC-contaminated groundwater to the National Priorities List. The sites include industrial, commercial, and residential areas as well as undeveloped land. The Area 4 site (also known as the Puente Valley Operable Unit) is a 23-square-mile sub-area. It includes the Main San Gabriel and the Puente Groundwater Basins. The site is located mostly in the cities of Industry and La Puente. It also includes some unincorporated parts of eastern Los Angeles County. The interim groundwater remedy will consist of three independent pump-and-treat systems to protect the water supply in the “mouth of the valley” part of the Puente Valley. The goal is to prevent migration of VOC-contaminant groundwater. Two of the systems have been constructed and are undergoing testing and should be fully operational in 2026. The third system is the design phase. Construction is estimated to begin in 2027. Meanwhile, water utilities in the area continue to provide municipal water that meets all state and federal drinking water standards. In 2019, EPA’s Superfund Job Training Initiative provided career development opportunities for 20 trainees living near the site, including certifications and hands-on training for construction and cleanup. Commercial and industrial businesses remain active on-site. Development of properties above the groundwater plume is ongoing. EPA will continue to work with developers and future tenants to make sure site uses remain compatible with the groundwater remedy.
Last updated October 2025
As of December 2024, EPA had data on 17 on-site businesses. These businesses employed 365 people and generated an estimated $48,655,980 in annual sales revenue. For additional information click here.
For more information:
SELMA PRESSURE TREATING COMPANY
The Selma Pressure Treating Company Superfund site is in Selma, California. A wood-treating company was active at the 18-acre area from 1936 to 1981. It includes the 4-acre former wood-treating facility and an adjacent vineyard used for drainage. Wood-treating activities contaminated soil and groundwater with chemicals, including hexavalent chromium. EPA added the site to the National Priorities List in 1983. Soil cleanup included digging up and stabilizing contaminated soil under protective caps. Groundwater cleanup treated chromium and placed restrictions on groundwater use. Groundwater treatment and monitoring are ongoing. Some contamination migrated off-site. EPA monitors private wells in the area and installed reverse osmosis systems on some private wells. The owner of the 4-acre former wood-treating facility leases the asphalt cap area for waste management and a recycling transfer yard. The former vineyard area now hosts industrial activities and storage facilities. The groundwater treatment system is also on the former vineyard area.
Last updated October 2025
As of December 2024, EPA had data on one on-site business. This business employed 5 people and generated an estimated $1,030,000 in annual sales revenue. For additional information click here.
For more information:
SIGNETICS, INC.
The Signetics, Inc. site covers 20 acres in Sunnyvale, California. The Signetics, Inc. site is part of the Triple Site, which also includes the nearby Advanced Micro Devices, Inc. (AMD) and TRW Microwave (TRW) Superfund sites. The three sites contributed to groundwater contamination in the north adjacent area known as the Offsite Operable Unit North American Philips Company (Philips) ran an integrated circuits manufacturing facility beginning in 1964 at the Signetics, Inc. site. Manufacturing processes used and generated hazardous substances, including trichloroethylene (TCE) and other organic solvents, acids, corrosives and metals. Initial investigation of soil pollution began in February 1982 after a leak in an underground waste solvent storage tank was detected. Contaminated soil was found during the tank removal. More investigations found that the two probable source areas of volatile organic compounds (VOCs) were the waste solvent tank area and a wastewater neutralization tank area. The combined Signetics, Inc., AMD and TRW sites’ comingled groundwater plume contaminated with VOCs, including TCE, extends about a mile north of the three sites. The Signetics Company, now referred to as Philips Semiconductors, manages the ongoing cleanup. It has included soil excavation, soil vapor extraction, and groundwater extraction and treatment. The adjacent Offsite Operable Unit includes more than 700 housing units and three school campuses. EPA has overseen Philips’ indoor air testing efforts in more than 35 school buildings and 237 homes and the installation of 25 school and residential mitigation systems. In 2019, EPA finalized an agreement with Philips that requires the company to evaluate options to speed the cleanup of groundwater in addition to continuously testing buildings for vapor intrusion. Also in 2019, EPA finalized two settlements with the potentially responsible parties at the AMD and TRW sites, which are part of the Triple Site Superfund Site. The requirements include ongoing vapor intrusion testing in all commercial buildings on-site and nearby homes, with mitigation as needed. Several businesses, including a home improvement store, a rock-climbing gym, and technology and consulting companies, are active on-site. Continued land uses at the Offsite Operable Unit include residential areas and schools.
Last updated October 2025
As of December 2024, EPA had data on 113 on-site businesses. These businesses employed 1,239 people and generated an estimated $193,220,658 in annual sales revenue. For additional information click here.
For more information:
SOLA OPTICAL USA, INC.
The 35-acre Sola Optical USA, Inc. former Superfund site is in Petaluma, California, about 30 miles north of San Francisco. Sola Optical made eyeglass lenses at the site from 1978 to 2001. The facility included a manufacturing building and an office building. In 1982, the state found acetone in a well on-site. Sola Optical reported contaminated soil next to underground solvent storage tanks. In 1985, the company removed the underground storage tanks and surrounding soil. Sola Optical also reported contamination in shallow groundwater under the site. EPA added the site to the National Priorities List in 1990. Sola Optical treated groundwater at the site from 1988 to 1997. In 2007, EPA agreed to allow the groundwater to recover naturally. In 2012, EPA confirmed that groundwater had achieved the cleanup standards. EPA took the site off the NPL in 2013. In 2000, RNM Cader bought about 11 previously undeveloped acres in the southwest part of the site. RNM Cader improved the site in 2005, adding building pads and parking lots. New York Life Investments acquired the partially developed property in 2014. It had plans for light industrial use. The 11-acre parcel now hosts the Cader Corporate Center. The center opened in 2016. Its three buildings provide over 268,000 square feet of light industrial, manufacturing, storage and distribution, and office space. Several other businesses are also on-site. They include a winemaking supply store and a dairy creamery. Another 24-acre part of the site is in use for truck storage and administrative offices.
Last updated October 2025
As of December 2024, EPA had data on 5 on-site businesses. These businesses employed 164 people and generated an estimated $38,879,220 in annual sales revenue. For additional information click here.
For more information:
- Reuse and the Benefit to Community: Sola Optical USA, Inc. Superfund Site (PDF)
- Superfund Site Profile Page
SOUTH BAY ASBESTOS AREA
The 550-acre South Bay Asbestos Area Superfund site is in the Alviso District of San Jose, California. Two landfills, Marshall and Santos, accepted asbestos-containing materials from an asbestos-cement pipe manufacturing plant. The town of Alviso used local rock containing naturally occurring asbestos to build levees and address flooding. Asbestos was found in the Guadalupe River ring levee and in soil at truck yards around Alviso. EPA added the site to the National Priorities List in 1986. Cleanup activities included removing the ring levee and disposing of asbestos-containing material, paving truck yards, putting in asphalt landfill caps, placing deed restrictions, establishing institutional controls, requiring landfill cap maintenance and inspections, and restoring wetlands. Long-term maintenance and regular inspections of the landfill covers are ongoing. Today, the site includes a mix of residential, recreational, ecological, light industrial and commercial land uses. EPA removed asbestos-contaminated soil and restored wetlands for the Environmental Education Center for the Don Edwards San Francisco Bay National Wildlife Refuge. EPA cleaned up 25 acres of wetlands and open space, providing wildlife habitat and walking trails. There are two business parks on-site. Gold Street Technology Center is on part of the former Santos Landfill. It provides commercial space and offices. The former Marshall Landfill is home to the America Center, a 70-acre business campus. The center includes office buildings, a hotel, a parking garage, and basketball and volleyball courts.
Last updated October 2025
As of December 2024, EPA had data on 16 on-site businesses. These businesses employed 2,757 people and generated an estimated $918,403,224 in annual sales revenue. For additional information click here.
For more information:
- Reuse and the Benefit to Community: South Bay Asbestos Area (PDF)
- Site Redevelopment Profile: South Bay Asbestos Area (PDF)
- Superfund Site Profile Page
SOUTHERN CALIFORNIA EDISON CO. (VISALIA POLEYARD)
The 20-acre Southern California Edison Co. (Visalia Poleyard) site is in Visalia, California. From 1925 to 1980, the Southern California Edison Company ran the Visalia pole treatment yard on-site. From 1925 to 1968, SCE used creosote to treat the utility poles. In 1968, SCE began using pentachlorophenol as a wood preservative for pole treatment. Leaking tanks, cracking pipes and treated poles contaminated groundwater and soil with chemicals, including creosote and pentachlorophenol. SCE first discovered groundwater contamination on-site in a well in 1966. EPA added the site to the National Priorities List in 1989. From 1966 to 1975, SCE led subsurface hydrogeologic investigations to find the nature and extent of contamination. Cleanup activities began in 1975 with the installation of extraction wells to remove and discharge contaminated groundwater to an off-site location for treatment. Cleanup actions in 1976 included the construction of a below ground slurry wall, groundwater removal, soil excavation, and the demolition of wood-treating facilities. In 1985, an on-site water treatment plant was installed. The plant was used until 1997, when it was replaced by a Visalia Steam Remediation Project system. Following cleanup activities, in 2009, EPA took the site off the National Priorities List,. The city of Visalia currently owns the site property and surrounding properties. The city’s public works department uses the property for office space, the parking and storage of vehicles and public works equipment, and for the stockpiling of sand and rock.
Last updated October 2025
As of December 2024, EPA had data on one on-site business. EPA did not have further economic details related to this business. For additional information click here.
For more information:
SPECTRA-PHYSICS, INC.
The 11.5-acre Spectra-Physics, Inc. Superfund site is in Mountain View, California. The 1-acre Teledyne Semiconductor Superfund site borders the site. Contaminated groundwater from both sites combined and migrated north toward San Francisco Bay. The owners of Spectra-Physics and Teledyne Semiconductor jointly manage the cleanup of the site. Spectra-Physics made electronic equipment and gas lasers on-site starting in 1961. Teledyne Semiconductor made semiconductors on-site starting in 1962. The manufacturing processes used a variety of chemicals, primarily volatile organic compounds, including trichloroethylene, which contaminated soil and groundwater. EPA added the site to the National Priorities List in 1991. In 1991, the Regional Water Board issued a Final Cleanup and Abatement Order and EPA issued a Record of Decision to address the combined groundwater plume. Responsible parties completed the soil cleanup in 1995. Groundwater treatment and investigation and mitigation of vapor intrusion in homes and commercial buildings are ongoing. In 2020, EPA issued a Record of Decision for Vapor Intrusion at the site requiring the use of engineering controls, institutional controls, and routine maintenance and monitoring requirements where appropriate. In 2023, EPA released a Record of Decision Amendment for Groundwater, altering the cleanup method from groundwater extraction to bioremediation, soil vapor extraction and treatment, monitored natural attenuation, and institutional controls. This new cleanup method will reduce the time it will take for groundwater to be cleaned up to drinking water standards. Lands above the affected groundwater area remain in commercial, industrial, residential and recreational use. Commercial and public service uses are ongoing on the Spectra-Physics property. One of the former facility buildings now hosts a church.
Last updated October 2025
As of December 2024, EPA had data on 7 on-site businesses. These businesses employed 156 people and generated an estimated $49,870,390 in annual sales revenue. For additional information click here.
For more information:
SYNERTEK, INC. (BUILDING 1)
The Synertek, Inc. (Building 1) Superfund site is in Santa Clara, California. From 1974 to 1985, Synertek made semiconductors at the site. Facility operations contaminated soil and groundwater with volatile organic compounds, primarily trichloroethylene. In 1985, Honeywell, the corporate successor to Synertek, removed leaking tanks, facility equipment and contaminated soils. Sampling found groundwater was contaminated. EPA added the site to the National Priorities List in 1989. Honeywell put in a groundwater extraction and treatment system that ran from 1987 to 2001. In 2011, a bioremediation method accelerated groundwater cleanup. With the oversight of EPA and the California Regional Water Quality Control Board (San Francisco Bay Region), Honeywell performed vapor intrusion assessments in 2013 and 2014 at the two commercial buildings nearest to the source area. The assessments found no evidence of unacceptable vapor intrusion. A solar company leases most of the on-site buildings for office space and for research and development of solar panels. Several other commercial businesses are also on-site.
Last updated October 2025
As of December 2024, EPA had data on 2 on-site businesses. These businesses employed 39 people and generated an estimated $3,520,000 in annual sales revenue. For additional information click here.
For more information:
TELEDYNE SEMICONDUCTOR
The 1-acre Teledyne Semiconductor Superfund site is in Mountain View, California, northwest of San Jose. The site consists of the former Teledyne Semiconductor and Spectra-Physics properties as well as the Teledyne/Spectra-Physics Combined Study Area. Starting in the early 1960s, Teledyne Semiconductor and Spectra-Physics used volatile organic compounds in the manufacturing processes on their respective properties. Teledyne Semiconductor made semiconductors on-site. Spectra-Physics made electronic equipment and gas lasers. Leaking tanks and sumps released trichloroethene and other VOCs that contaminated the soil and groundwater at both properties. Contaminated groundwater from both sites combined and migrated north toward San Francisco Bay. In the early 1980s, the Regional Water Board called for environmental investigation and remediation activities. EPA added the site to the National Priorities List in 1987. In 1991, the Regional Water Board issued a Final Cleanup and Abatement Order and EPA issued a Record of Decision to address the combined groundwater plume. The owners of Spectra-Physics and Teledyne Semiconductor jointly manage the cleanup. Cleanup activities have included groundwater extraction and soil vapor extraction. Soil cleanup finished in 1995. In 2020, EPA issued a Record of Decision for Vapor Intrusion at the site requiring the use of engineering controls, institutional controls, and routine maintenance and monitoring requirements where appropriate. In 2023, EPA released a Record of Decision Amendment for Groundwater, altering the cleanup method from groundwater extraction to bioremediation, soil vapor extraction and treatment, monitored natural attenuation, and institutional controls. Groundwater treatment and investigation, monitoring and mitigation of vapor intrusion in homes and commercial buildings is ongoing. The Teledyne Semiconductor property remains in continued commercial and light industrial use, including several laboratories. The land above the affected groundwater area remains in continued commercial, industrial, residential and recreational use. Recreational uses include a playground and a softball field.
Last updated October 2025
As of December 2024, EPA had data on one on-site business. This business employed 671 people and generated an estimated $47,320,000 in annual sales revenue. For additional information click here.
For more information:
TRW MICROWAVE, INC (BUILDING 825)
The TRW Microwave, Inc Superfund site is located in Sunnyvale, California. The TRW site is part of the Triple Site, which also includes the nearby Advanced Micro Devices, Inc. (AMD) Superfund site and the Signetics, Inc. Site. The three sites contributed to groundwater contamination in the north adjacent area known as the Offsite Operable Unit. The main activity at the TRW site was the assembly and testing of microwave components. Facility operations contaminated soil and groundwater with volatile organic compounds, primarily trichloroethylene (TCE). EPA added the TRW site to the National Priorities List in 1990. EPA selected a remedy for the site in the 1991 Record of Decision, together with the AMD and Signetics sites, and the Offsite Operable Unit. TRW and its corporate successor, Northrup Grumman Systems Corporation, treated and removed contaminated soil and treated contaminated groundwater from 1986 to 2001. A groundwater treatment pilot study using enhanced anerobic biodegradation (EAB) began in 2000, before the groundwater extraction treatment system was discontinued in 2001. A developer bought the TRW site property in 1995. The developer leased the building to research and development companies until 2001. From 2001 to 2003, the owner demolished portions of the existing structure and renovated a 2-story building on a similar footprint. In 2013, with EPA’s oversight, Northrup Grumman did a vapor intrusion assessment of the building, which found TCE indoor air concentrations above screening levels that aim to protect public health. Mitigation measures included source removal/remediation, sealing floor cracks and openings, a new HVAC system and a sub-slab passive venting system. Indoor air testing in 2014 and 2015 confirmed the effectiveness of the mitigation measures before the current tenant, a technology company, moved in. The building continues to be occupied. Groundwater monitoring is ongoing. Additional confirmatory indoor air testing performed in 2023, 2024 and 2025 provided long term stewardship and confirmed that the indoor air concentrations remain below screening levels that aim to protect public health.
Last updated October 2025
As of December 2024, EPA had data on one on-site business. EPA did not have further economic details related to this business. For additional information click here.
For more information:
UNITED HECKATHORN CO.
The United Heckathorn Co. Superfund site is on Richmond Harbor in Contra Costa County, California. Dry bulk cargo distribution and shipping take place at the site. The site includes 5 acres of land (the upland area) and about 15 acres of marine sediments in the Lauritzen Channel and Parr Canal of Richmond Harbor. The marine area provides habitat for many marine and avian species. From 1947 to 1966, the United Heckathorn facility made, packaged and shipped pesticides from facilities on-site. During this time, the site was poorly managed. Releases of pesticides and other chemicals contaminated the upland and marine areas. EPA added the site to the National Priorities List in 1990. Cleanup took place from 1990 to 1999. It included digging up contaminated areas, dredging the Lauritzen Channel and Parr Canal and capping 5 acres of land in the upland area. The Levin-Richmond Terminal Corporation (LRTC) bought the upland area in 1981. LRTC now runs a marine shipping terminal at the former United Heckathorn facility. LRTC uses the area for cargo stockpiling and railroad operations. LRTC and Manson Construction, a dredging contractor, continue to use the Lauritzen Channel as a deep-water channel. Parr Canal is not in use. In 1999, EPA found high levels of pesticides remaining in the Lauritzen Channel. Monitoring data from 2001 to 2016 showed that cleanup goals have not been met in the channel over time. EPA is leading site investigations in this area and will select a new remedy for the channel.
Last updated October 2025
As of December 2024, EPA had data on one on-site business. EPA did not have further economic details related to this business. For additional information click here.
For more information:
WASTE DISPOSAL, INC.
The 38-acre Waste Disposal, Inc. Superfund site is in Santa Fe Springs in Los Angeles County, California. EPA completed a remedial action at the complex site in 2006 that included capping, soil vapor control, institutional controls, long-term operation and maintenance activities, and monitoring. Current work focuses on supporting potential beneficial reuse. From the early 1940s to the mid-1960s, businesses disposed of waste in a reservoir on-site. In 1984 and 1985, testing by the city of Santa Fe Springs found that waste-disposal activities contaminated soil and groundwater with hazardous chemicals. EPA added the site to the National Priorities List in 1987. The potentially responsible parties capped contaminated soils, removed and treated gases, and restricted groundwater use. To prevent potential damage to the cap, institutional controls prohibit on-site construction without EPA approval. Monitoring is ongoing. Grass was put in to protect the cap and improve stormwater drainage. EPA worked with state agencies, potentially responsible parties (PRPs), business owners and landowners to make sure businesses could remain open during cleanup. EPA’s Superfund Redevelopment Program gave Santa Fe Springs a pilot grant to develop a site reuse plan compatible with commercial and industrial development. The city adopted the plan in 2004. It provides site reuse concepts and identifies building requirements and design guidelines. The PRPs repaved driveways, parking areas and walkways as part of the protective cap. They also worked with a nearby high school to address public safety concerns. The PRPs also built a backstop behind the school’s baseball and soccer fields to prevent stray balls from coming onto the site. Today, over 30 commercial and light industrial businesses are on-site. They include equipment rental and construction companies and vehicle maintenance facilities. A developer purchased a large part of the site in 2018 and has been coordinating with EPA, the city of Santa Fe Springs and other stakeholders on commercial redevelopment plans. EPA’s Superfund Redevelopment Program funded a regional support project at the site that finished in 2022. Meanwhile, EPA continues to work with the developer, PRPs and community stakeholders to support site reuse opportunities.
Last updated October 2025
As of December 2024, EPA had data on 15 on-site businesses. These businesses employed 98 people and generated an estimated $10,121,268 in annual sales revenue. For additional information click here.
For more information:
WATKINS-JOHNSON CO. (STEWART DIVISION PLANT)
The 43.7-acre Watkins-Johnson Co. (Stewart Division Plant) Superfund site is in Santa Cruz County, about 5 miles north of Santa Cruz, California. From 1963 to 1999, Watkins-Johnson made semiconductors at the site. Operations at its facility contaminated the Santa Margarita aquifer, a major source of groundwater in the area. EPA added the site to the National Priorities List in 1990. Manufacturing activities continued until 2011. Watkins-Johnson led soil and groundwater cleanups from 1986 to 2016. Several commercial and industrial businesses are on-site, including a roller derby practice rink. In 2013, a developer purchased the site property. The developer petitioned the city of Scotts Valley to rezone the property for residential uses. The city denied the rezoning request and the site remains in commercial and industrial use.
Last updated October 2025
As of December 2024, EPA had data on 2 on-site businesses. These businesses employed 14 people and generated an estimated $1,710,000 in annual sales revenue. For additional information click here.
For more information:
WESTERN PACIFIC RAILROAD CO.
The 90-acre Western Pacific Railroad Company Superfund site is located just south of Oroville, California. From 1920 to 1982, the Western Pacific Railroad Company (WPRR) used the site to fuel, repair, and maintain railcars in a 10-acre area known as the Fueling Area. In the 1970s, WPRR moved diesel maintenance operations out of Oroville and leased the Fueling Area to an independent railcar company, Solano, which operated until 1991. The subsequent owner, Union Pacific Railroad (UPRR), continued to utilize portions of the site until 1991, when UPRR cleared the area and demolished the remaining structures. These historic industrial practices contaminated the on-site soil with polycyclic aromatic hydrocarbons. Additionally, a leaking underground storage tank contaminated the groundwater with volatile organic compounds. In response, EPA added the site to the National Priorities List (NPL) in 1990. EPA selected the final remedy for the site in 1997. Initial cleanup actions included the removal and transport of contaminated soil and sludges, soil sampling, and the emptying of an underground oil/waste separator, which was then backfilled with clean soil. In 1998, UPRR removed contaminated soil from the site and replaced it with clean fill. In 1994, UPRR installed a groundwater extraction and treatment system. A second groundwater extraction well, along with a soil vapor extraction unit, was installed in 1997. Groundwater treatment activities concluded in 1999, and the soil vapor extraction unit stopped operating in 2000. After the completion of the cleanup, EPA removed the site from the NPL in 2001. Institutional controls are now in place to prevent non-industrial use of the site. The former Fueling Area property currently houses a UPRR, maintenance shop, a small classification yard, and a rail line that follows the Feather River over the Sierra Nevada Mountains.
Last updated October 2025
As of December 2024, EPA did not have economic data related to on-site businesses, or economic data were not applicable due to site use. For additional information click here.
For more information:
WESTINGHOUSE ELECTRONIC CORP. (SUNNYVALE PLANT)
The 75-acre Westinghouse Electric Corp. (Sunnyvale Plant) Superfund site is in Sunnyvale, California. The area was first in use as a heavy industrial facility that made steam engines, marine propulsion systems and missile-launching systems for the U.S. Department of Defense. During the mid-1950s, the Westinghouse Electric Corporation (Westinghouse) used the facility to make electrical transformers. During operations, a leaking storage tank, spills and the use of transformer fluids and mineral oil contaminated soil and groundwater with polychlorinated biphenyls (PCBs), volatile organic compounds, fuel and other hazardous substances. In 1984 and 1985, Westinghouse removed or paved contaminated surface areas and removed and treated contaminated groundwater. In 1986, Westinghouse removed an on-site gasoline tank and EPA added the site to the National Priorities List. In 1994, Westinghouse continued long-term groundwater and soil remediation. Activities included the extraction and treatment of groundwater and the excavation and incineration of contaminated soil. Full-scale groundwater treatment began in 1995. Land use restrictions are in place on-site. Groundwater treatment is ongoing. In 1996, a U.S. defense contractor bought the site property. It makes steam generators, marine propulsion systems and missile launching systems for the federal government. A parking lot and a commercial office building are on the northern part of the site. An iron works museum is also on-site.
Last updated October 2025
As of December 2024, EPA had data on 2 on-site businesses. These businesses employed 1,106 people and generated an estimated $428,073,442 in annual sales revenue. For additional information click here.
For more information: