PROJECT ARCHIVES:
Private Residence
Salisbury, Maryland

In November 2005, a release of heating oil occurred during re-fueling of an aboveground storage tank (AST) system located at a residential property in Salisbury, Maryland (Site). The release impacted exterior surface soils, building components including vinyl siding and the concrete block foundation and surface soils within the interior of the crawl space proximate to the AST location. The fuel oil delivery company initiated immediate response actions consisting of a limited soil removal along the exterior foundation of the residence.

In December 2005, due to continued fuel odors within the living quarters of the residence, Arc Environmental was contacted by the insurance company of the fuel oil delivery company to further evaluate these odors and to initiate any necessary follow-up response actions. Our response consisted of a visual reconnaissance of the release area, including an inspection of the crawl space underlying the residence, and field screening interior and exterior air for evidence of petroleum vapors using a photoionization detector (PID). A strong fuel oil odor was observed in the immediate area of the release and inside the residence. In addition, PID readings of up to 60 PID units were recorded in the crawl space of the residence and PID readings of up to 25 PID units were observed in the living quarters of the residence. The presence of petroleum impacted soil was also identified beneath the crawl space of the residence.

Based on these findings, Arc Environmental initiated immediate response actions at the Site within 24-hours of our initial Site visit. First, Arc Environmental arranged for temporary housing for the residents at a local hotel/motel for the duration of the remediation. Secondly, petroleum vapors accumulating within the interior of the crawl space and residence were immediately removed using a temporary ventilation system consisting of a vacuum blower installed at the entrance of the crawl space that discharged to an open space area in the rear of the residence. Within one hour of the system start-up, ambient air concentrations in the living quarters were reduced to less than 9 PID units and to 0.0 PID units the following day.

Without compromising the structural integrity of the residence, approximately five tons of residual petroleum impacted soils were removed from the crawl space area. Following excavation, the interior and exterior exposed surfaces of the foundation and exterior vinyl siding of the residence were then cleaned using a laboratory grade detergent and sealed with a Kilz© primer. The excavation was backfilled with clean sand to surface grade and the entire ground surface and ceiling of the crawl space was covered with 6-mil polyethylene sheeting. The ventilation system was permanently taken off-line once confirmatory field screening conducted over several days indicated ambient air concentrations less than 0.0 PID units within both the crawl space and interior of the residence.

Although petroleum vapors had been permanently mitigated, lingering petroleum odors were present within the interior of the residence. As such, a carbon filter was installed within the heating, ventilation and air conditioning system to remove any residual odors that may have been introduced into the duct work located within the crawl space. In addition, Arc Environmental arranged for a cleaning service to steam clean the upholstered surfaces (curtains, carpeting and furniture) and purge the interior of the residence with ozone.

At the completion of our response, the property was restored to the satisfaction of both the residents and the insurance company. In addition, our quick response allowed the property owner to return to their residence within a week of initiation, just in time to celebrate the Holidays.