Based on a recommendation from Frey Environmental, the consultants to the former owners of the Pine Cove Market and gas station, the Riverside County Department of Environmental Health is preparing to close the leaking underground storage tank case.

The draft closure summary reports, “Vapor and groundwater sampling show a major reduction of hydrocarbons in soil and ground water beneath the site. The estimated hydrocarbon mass remaining in the groundwater beneath the site is one pound (0.2 gallons).”

On June 4, FREY Environmental wrote the DEH recommending no further action and case closure. In an Oct. 22 letter to Howard Friedman, the DEH concurred.

“Based on the available data, both agencies [the county DEH and the state Regional Water Quality Control Board for the Santa Ana region] concur to proceed with case closure,” wrote Linda Shurlow, environmental health specialist, and Sharon Boltinghouse, associate public health professional geologist.

The past remediation efforts in 2009 and 2011 have removed contaminants. Subsequent monitoring has not detected any renewed or persistent threat, according to FREY’s latest report.

“Based on the low to non-detect levels of petroleum hydrocarbons in soil vapor and groundwater beneath the site, petroleum hydrocarbons do not pose a threat to human health or the environment,” Frey concluded in June.

No drinking wells or surface water is in danger, Frey reported. The eight monitoring wells will be decommissioned as part of the process to close the case, according to DEH.

The case was initially opened in November 1994, when two 4,000-gallon underground tanks were removed. Soil samples detected high concentrations of total petroleum hydrocarbons.

A notice of proposed closure will be distributed next week. Public comments will be solicited on the proposed closure and may be sent to Shurlow at County of Riverside, Department of Environmental Health, 47950 Arabia Street, Indio, CA 92201.

A summary of the reason for case closure can be found here.

Comments will be accepted through Jan. 10, 2013. For further information, Shurlow may be called at (760) 863-7570 or emailed at [email protected].