Draft Removal Action Workplan for Groundwater - Voi-Shan Chatsworth Site


SCH Number
Public Agency
Department of Toxic Substances Control
Document Title
Draft Removal Action Workplan for Groundwater - Voi-Shan Chatsworth Site
Document Type
NOE - Notice of Exemption
Document Description
This project consists of the continuation of the operation of the existing groundwater pump and treatment system that has been installed at the Site. Previous investigations have shown that the contaminants of concern are volatile organic compounds (VOCs) including perchloroethylene (PCE), 1, 1, 1-trichloroethane (1,1-TCA) and 1, 1-dichloroethylene (1,1-DCE) were present in the soil and groundwater underneath the Site. VOCs in the soil were remediated by soil vapor extraction under a Voluntary Cleanup Agreement between DTSC and Mairoll, Inc., the project proponent. The performance based soil cleanup level was achieved in 1998 after two years of soil vapor extraction. This cleanup level was below health risk levels. The groundwater pump and treatment sytem has been in operation for four years, although not under DTSC oversight. A draft Removal Action Workplan (RAW) for groundwater has been prepared that details the proposed remedy. The draft RAW specificies that the groundwater pump and treat system approved by DTSC and currently operating at the site be continued until the maximum contaminant level (MCL) for each contaminant of concern is reached in the hydraulically downgradient wells. This will prevent groundwater with VOC levels above MCLs from leaving the Site. Following the approval of the final RAW, Mairoll will enter into an Operation and Maintenance (O&M) Agreement with DTSC which requires the project proponent to perform prescribed maintenance on the treatment unit and collect and analyze groundwater samples. The groundwater treatment unit shall remain in operation until the project proponent has met the criteria specified in the final RAW. This is expected to take one to two years.

Contact Information

Richard Gebert
Agency Name
Department of Toxic Substances Control
Contact Types
Lead/Public Agency


Los Angeles
Other Location Info

Notice of Exemption

Exempt Status
Categorical Exemption
Type, Section or Code
Section 15330
Reasons for Exemption
The project consists of a minor cleanup action taken to mitigate the release of a hazardous waste or substance. The removal action will cost less than $1 million, and the site is not on the Hazardous Waste and Substances Sites (Cortese) List pursuant to Government Code Section 65962.5. There are no known historical features located at the site. The site is not designated as an area of critical habitat for sensitive threatened, or endangered species. The neighborhood is a mixture of commercial business and industrial manufacturing. A trailer park about 1/2 mile from the Site is the only residential area near the Site. There are no sensitive uses near the Site. The proposed project will have no significant impact on the environment because the overall disturbance to the affected area is anticipated to be minimal. Control measures are in place to ensure that the neighborhood is safe from any air emissions from the treatment unit. The groundwater is inspected at least monthly. The site does not support any riparian habitat or other sensitive natural community identified in local or regional plans, policies or regulations or by the California Dept. of Fish and Game or U.S. Fish and Wildlife Service.

Disclaimer: The document was originally posted before CEQAnet had the capability to host attachments for the public. To obtain the original attachments for this document, please contact the lead agency at the contact information listed above. You may also contact the OPR via email at state.clearinghouse@opr.ca.gov or via phone at (916) 445-0613.

Download CSV New Search Print