The former Ron's Discount Energy Mart Site (aka Penny Hill Mobil, Inc. and Infanzon Auto Repair) on Philadelphia Pike, Claymont, DE (Updated May 22, 2014)
The Department of Natural Resources and Environmental Control’s (DNREC’s) Tank Management Section is in the final stages of corrective actions following a petroleum release in a Claymont neighborhood. The most recent work focused on addressing potential risks posed by petroleum vapors from residual contamination in soil and groundwater. The 1988 petroleum release occurred at 2509 Philadelphia Pike in Claymont – formally doing business as Ron’s Discount Energy Mart.
The release came from the underground storage tank system that was located at the site. Once the problem was discovered, the tanks and contaminated soils were removed, and measures were taken to control petroleum vapors that impacted several homes on Hillside Road. However, dissolved petroleum compounds continued to be carried by groundwater from the release site toward the homes along Hillside Road. DNREC took over the cleanup actions at the site after the responsible party, Ronald Palimere, failed to take appropriate action. Over the years, the following cleanup actions have been conducted:
1993: Removal of the tanks and over-excavation of heavily contaminated soils;
1988-present: Testing soil and groundwater to determine the extent of the contamination;
1989-1992: Controlling vapors that affected several homes on Hillside Road;
2005: Injecting Oxygen Releasing Compound (ORC) into the soil beneath the upper part of Hillside Road, where contaminant concentrations remained greatest;
2009-2010: Vapor intrusion investigations at the former Ron's Discount Energy property, and residences along upper Hillside Road,
2010-2011: Installation of vapor mitigation measures at two homes on Hillside Road;
2011-2014: Operations and Maintenance inspections of vapor mitigation systems;
May 2013: No Further Action (NFA) status assigned to the property at 2509 Philadelphia Pike; and,
Continued testing of groundwater to date to monitor conditions beneath Hillside Road.
ORC is a non-toxic compound that provides oxygen to the soil and groundwater to stimulate the break down of petroleum compounds by naturally occurring microbes. Following injection, groundwater quality has been monitored by sampling wells at the former gas station site, and at locations along Hillside Road. Data indicate that the ORC had a positive effect, as shown by decreased concentrations of dissolved petroleum compounds. DNREC continues to monitor conditions to ensure public safety.
The release resulted in extensive cleanup costs paid from Delaware’s Hazardous Substance Cleanup (HSCA) Fund. On July 31, 2009, DNREC issued a Notice of Administrative Penalty Assessment and Secretary’s Order to the owners, Ronald C. Palimere and Penny Hill Mobil Inc., which included $447,125 in penalties for failure to clean-up the release and $712,887 in cost reimbursement to the Department for cleanup expenses. According to Delaware law, the parties responsible for the release are liable for all past and any future costs associated with the Department’s efforts to clean up the site. DNREC continues its efforts to recover costs from the responsible parties.
Vapor Mitigation at Two Hillside Road Residences: Two rounds of soil vapor and indoor air quality monitoring were performed at residences along Hillside Road, in addition to soil vapor monitoring at the former Ron’s Discount Energy property. Results indicated the potential for petroleum vapor intrusion, as well as episodes of nuisance odors, in two residences, 9 and 10 Hillside Road. The basement sump at 9 Hillside Road was repaired to vent vapors outdoors. A french drain and a venting system were installed at 10 Hillside Road. Follow-up inspections of both homes have confirmed the successful operation of the mitigation systems.
Stressed Trees Inspected: The State’s urban forester (from the Delaware Forest Service) examined trees along Hillside Road. Some trees appeared to be stressed, and it was concluded they are affected by a common fungus. The observed stress was not attributed to the petroleum release.
Current Actions: No Further Action status was assigned in May 2013 to the property at 2509 Philadelphia Pike. Low-level contamination remaining underground at the property no longer poses a risk and is no longer migrating off-site. Additional inspections of the vapor mitigation systems and groundwater testing along Hillside Road may be performed. If a new owner acquires the former Ron’s Discount Energy Mart property, the new owner may perform additional sampling at the property prior to any redevelopment.
Site information may be reviewed using the Delaware Environmental Navigator. The facility is listed as Former Ron’s Discount Energy Mart; facility ID # 3-000712.
Information for Review:
· General information on vapor intrusion:
For more information, please contact:
Delaware Department of Natural Resources and Environmental Control
Tank Management Branch