Pacific Southwest, Region 9: Superfund
Serving Arizona, California, Hawaii, Nevada, the Pacific Islands, and Tribal Nations
San Fernando Valley (area 3 Verdugo)
EPA #: CAD980894984
County: Los Angeles
Congressional District: 27
Other Names: (1) Verdugo NPL Site, (2) Glorietta Wellfield Area
On this page
Description and History
NPL Listing History
NPL Status: Final
Proposed Date: 10/15/84
Final Date: 06/10/86
Deleted Date: 10/12/04
San Fernando Valley (Area 3) is part of the Verdugo Basin which is situated in the eastern portion of the San Fernando Valley Basin (SFV), and covers an area of about 4,400 acres. The basin is bounded on the northeast by the San Gabriel Mountains, on the west by the Verdugo Mountains, and on the southeast by the San Rafael Hills. All the surface water channels feed into the Verdugo Wash, which is located along the west side of the basin. Land use in the Verdugo Basin is primarily residential along the floor of the valley, and undeveloped (open space) in surrounding mountains. A northwest-oriented strip of commercial development is present along Foothill Boulevard, and a Y-shaped commercial sector is present in the southern portion of the basin. The basin contains four scattered agricultural areas, and no industrial development.
In 1983, pursuant to California Assembly Bill 1803, wells within the SFV were sampled for volatile organic compounds (VOCs), semi-volatile organic compounds, and pesticides/herbicides. Results of this sampling revealed concentrations of VOCs in the Verdugo Basin in excess of Safe Drinking Water Act maximum contaminant levels (MCLs) in several water supply production wells in this basin. In 1986, at the request of the State of California, EPA designated four areas within the SFV as National Priorities List sites: North Hollywood (Area 1), Crystal Springs (Area 2), Pollock (Area 4) and Verdugo (Area 3).
EPA subsequently entered into a cooperative agreement with the Los Angeles Department of Water and Power (LADWP) to conduct a Remedial Investigation (RI) of the SFV. Since the completion of the RI in 1992, EPA has continued to monitor groundwater quality by sampling groundwater wells in the Verdugo Basin four times a year as part of EPA’s basin wide RI monitoring effort. Data from these sampling events are used to map the presence and extent of groundwater contaminants.
The right to use groundwater in the Verdugo Basin is strictly controlled by a 1979 adjudicated judicial agreement (Judgment) concerning water rights in the SFV. Under the Judgment only the City of Glendale and the Crescenta Valley Water District (CVWD), formerly the Crescenta Valley County Water District, can use surface and groundwater in the Verdugo Basin. Groundwater within the Verdugo Basin is used as a potable source of supply by the City of Glendale and the CVWD. The CVWD operates the Glenwood and Mills well fields while the City of Glendale operates the Glorietta well field.
Contaminants and Risks
The groundwater is minimally contaminated with VOCs in small isolated areas in concentrations near or below the maximum allowable levels. Tetrachloroethene (PCE) is the most prevalent organic contaminant in the basin. The maximum concentration of PCE reported in the Verdugo Basin is 52 ppb (parts per billion) during July 1989. The area of greatest PCE groundwater contamination was located in and near the Glenwood well field where historic concentrations averaged between 5 ppb and 20 ppb throughout the 1980’s. The most recently available data (2002) indicate PCE concentrations of less than 1.4 ppb in the Glorietta Well Field, and less than 2.3 ppb in the Glenwood/Mills Well Field. Current PCE contaminant levels in the Verdugo Basin are below the federal and State MCL of 5 ppb. Overall, PCE contamination in the Verdugo Basin is less widespread and at lower concentrations than in the past.
Nitrate contamination of groundwater in excess of the 45 ppm (parts per million) state MCL (expressed as NO3) has been detected throughout a large portion of the Verdugo Basin. To date, the maximum concentration of nitrate detected in the Verdugo Basin is 101 ppm during February 1995. Between 1988 and 2002, nitrate values in the Glorietta and Glenwood Well Fields have remained at approximately the same concentrations, with ranges from 25 to 50 ppm and 40 to 90 ppm, respectively. The maximum concentration of nitrate in EPA’s monitoring wells is 86.8 ppm detected in 1993. Potential sources of nitrate contamination include fertilizer applied during agricultural practices, animal waste from confined animal facilities, and septic tank effluent.
Investigation and Cleanup Activities
Based on the lack of significant VOC contamination in the basin, and the existing blending and treatment for nitrate, EPA proposed a no-action remedy for this site in October 2003. Comment period for the proposed plan was from November 5 to December 6, 2003. EPA signed the Record of Decision (ROD) document on February 24, 2004.
The results from groundwater monitoring conducted from the early 1980's through December 2002 indicated that the low levels of VOC contamination at the Site were within EPA’s acceptable risk range and met State and federal MCLs. No activities using removal authority were conducted at this site.
Site-specific screening-level human health and ecological risk assessments were conducted to support EPA’s proposal for no remedial action for the Verdugo Study Area (CH2M HILL, October 2003). Potential risks to human health associated with exposure to chemicals of potential concern in groundwater were found to be within EPA’s acceptable risk range. There were no ecological risks found for the compounds present, as no completed exposure pathways exist for eco-receptors.
The EPA, with concurrence of the State of California, determined that the release posed no significant threat to public health or the environment, and, therefore, taking of remedial measures was not appropriate. EPA Published Direct Final Notice of Deletion and Notice of Intent to Delete on August 10, 2004 in the Federal Register. EPA received no comments during and after the comment period. Therefore EPA deleted this site from the NPL list on October 12, 2004.
The basinwide RI was completed in 1992, and EPA has conducted quarterly groundwater monitoring since then. To date, PCE has been the only VOC detected at or above the maximum contaminant level (MCL) of 5 ppb. PCE levels are currently less than the MCL.
EPA issued a no action ROD for the Verdugo site in February 2004. EPA deleted this site from the NPL list on October 12, 2004.
Groundwater within the Verdugo Basin is used as a potable source of supply by two purveyors: the City of Glendale and the Crescenta Valley Water District (CVWD). The CVWD operates the Glenwood and Mills Well Fields, while the City of Glendale operates the Glorietta Well Field. To maintain adequate supplies of high quality water, both CVWD and the City of Glendale maintain facilities to treat or otherwise address nitrate contamination in the Verdugo Basin. Treatment of groundwater for VOC contamination has not been a concern due to the low concentrations present. Both the CVWD and the City of Glendale blend groundwater containing nitrate with imported water prior to distribution to customers. CVWD is currently operating the Glenwood Nitrate Water Treatment Plant, using an ion-exchange process for nitrate removal. The City of Glendale blends Verdugo Basin groundwater at its Glorietta Reservoir Complex; the mix ratio varies from 2:1 to 10:1 depending on the amount of imported water obtained from the Metropolitan Water District being introduced at the reservoir. The blending insures that levels of nitrate are in the 22-28 ppm range, well below the 45 ppm State standard for potable water.
Cleanup Results to Date
Based on the lack of significant VOC contamination in the basin, and the existing blending and treatment for nitrate, EPA has determined that conditions do not warrant remedial action under Superfund and site has been deleted from the NPL.
Potentially Responsible Parties
Potentially responsible parties (PRPs) refers to companies that are potentially responsible for generating, transporting, or disposing of the hazardous waste found at the site.
No-Further-Action ("NFA") Letter recipients
Under a cooperative agreement between EPA and the State Water Resources Control Board, the California Regional Water Quality Control Board, Los Angeles Region ("RWQCB") is conducting assessments of facilities in the San Fernando Basin to determine the extent of solvent usage and to assess past and current chemical handling, storage and disposal practices. Based on information provided to EPA by the RWQCB, the entities who received the "No-Further-Action" letters will not be asked by EPA or the RWQCB to participate in regional ground-water cleanup projects currently planned for the San Fernando Basin Superfund Sites. These entities are no longer part of the EPA Superfund process for the San Fernando Basin sites, and the RWQCB and EPA plan no further action at these facilities. Click here for the list of No-Further-Action letter recipients.
General Notice Letter ("GNL") and Special Notice Letter ("SNL") Recipients
A GNL notifies an entity that EPA has identified the entity as a potentially responsible party ("PRP") for the purpose of Superfund response actions. Besides designating a facility or person as a PRP, the GNL is used to encourage PRP coalescence and formation of steering committees, an important step prior to negotiations with EPA for Superfund response work, both investigatory and remedial.
An SNL, in addition to designating an entity as a potentially responsible party ("PRP"), initiates a formal settlement process between EPA and the PRPs. The SNL is used to facilitate an agreement between EPA and the PRPs for the PRPs to conduct site work and to pay EPA's oversight and other response costs. The SNL requests an offer from PRPs to perform these actions and sets a formal time period for negotiations to be completed, after which EPA may unilaterally order the PRPs to undertake the site work and to pay EPA's oversight costs, and initiate a lawsuit to recover EPA's other response costs.
Click here for the list of General Notice and Special Notice letter recipients.
Documents and Reports
Public Information Repositories
The public information repositories for the site are at the following locations:
City of Glendale Public Library,
222 East Harvard Street,
Glendale, CA 91205
Los Angeles Department of Water and Power (LADWP) Library,
111 North Hope Street, Room 518
Los Angeles, CA 90012
EPA Site Manager
Mail Code SFD
75 Hawthorne Street
San Francisco, CA 94105
EPA Community Involvement Coordinator
Mail Code SFD
75 Hawthorne Street
San Francisco, CA 94105
EPA Public Information Center
Chatsworth, CA 91311-6505
After Hours (Emergency Response)