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Petroleum Product Contamination

WES has investigated several hundred petroleum product releases over the past few decades. The product lost has included gasoline, jet fuel, diesel fuel, lube oils and pure product components such as xylene. The environments where the losses have occurred have ranged from metamorphic rocks and residuum in the Piedmont to unsaturated Ridge sands to swamps with standing water.

In the past, we conducted emergency response actions and directly supervised removal of product-impacted soils. However, we now concentrate on coordinating with first responders to fine-tune their efforts and insure that the post-cleanup assessment and remediation is minimized. We have employed a variety of methods to assess and remediate petroleum hydrocarbon contamination. We select the remediation method most appropriate to the product type and environment where the loss took place based on the data analysis and our extensive experience with product releases.

Soil Recovery from Product Release at Service Station

Episodic Air Sparging and Soil Vapor Extraction

At the above site and many others, we have used a combination of direct source removal through excavation followed by episodic ground water treatment with air sparging and soil vapor extraction (SVE). Our sites have been rapidly remediated and closed using this technology in even the most complex environments

Site Schematic showing monitor wells, ground water flow direction, water quality results and outline of excavated/remediated area with utilities.

Under the heading of "complex environments," WES recently remediated this site which was contaminated by several thousand gallons of strongly weathered diesel fuel. The assessment and remediation activities were hampered by the physical conditions at the site, a former cypress dome that had been infilled with dense dolomite boulders many decades ago when the property was developed. The remediation involved setting up an ad hoc mining operation to cull the rock from the product-impacted soil. Once segregated, the petroleum-impacted soil was thermally treated.

Collection of depth and location (x,y,z) data from remediated excavation by conventional survey and sub-meter accurate gps. Volume calculations were obtained using this data and a cut-and-fill estimation software. A 3-dimensional representation of the remediated area is shown below.