JACKSON, DANA S., and PAUL SCOVAZZO, Kemron Environmental Services, Inc., McLean, VA

ABSTRACT: Bioremediation of Petroleum-Contaminated Soils: The Environmental Restoration of a Former Railyard

Petroleum contamination is a pervasive environmental problem. The common remedial solution has been to excavate and landfill the contaminated soils, which is hampered by high costs and space limitations at traditional disposal facilities. Bioremediation is a more attractive soil remediation alternative. This method is winning favor primarily because the soil can be treated on site, and the bioremediation systems can function without interfering with existing facilities. Although the concept of bioremediation has existed for many years, its acceptance as a cost-effective approach to remediation is only now being realized.

Several problems must be addressed when considering bioremediation, including variables such as porosity and permeability of soil, indigenous or off-the-shelf microbes, availability of water, and how to best distribute nutrients to the microbes. This paper will answer how some of these questions were addressed at one site near Baltimore, Maryland.

The site was part of a former diesel locomotive refueling station at a retired railyard. The levels of contamination of total petroleum hydrocarbons (TPH) ranged from less than 100 parts per million (ppm) to greater than 14,000 ppm. The total volume of soil estimated to require treatment was 70,000 yd3. At the Baltimore site we used indigenous bacteria. Groundwater was extracted, augmented with nutrients and oxygen through mobile treatment trailers, and returned to the soil for infiltration. This method creates an environment where the bacteria can naturally degrade the petroleum hydrocarbons to acceptable levels. Once these levels are achieved, the redevelopment of prime real estate can begin.

AAPG Search and Discovery Article #90995©1993 AAPG Eastern Section Meeting, Williamsburg, Virginia, September 19-21, 1993.