Bioremediation of Four Former Soviet Military Bases in Hungary: Experience Useful for Future Decision-Making

Abstract

Large quantities of soils were contaminated with various types of petroleum hydrocarbons at four former Soviet military bases in Transdanubian Hungary. The contamination resulted from approximately forty years of improper storage and handling of fuels and oils used in association with military operations at the four sites. These sites are a heliport at Székesfehérvár, and combat support bases in Veszprém, Tab, and Dombóvár. Much of the contamination, consisting of various components of kerosene, diesel oil, heating oil, gasoline, and lubricating oils and greases, was the result of uncontrolled releases from fuel and oil storage tanks, both underground and aboveground.

At the four sites scheduled for cleanup over a period of about three years and in the framework of several contracts with the Hungarian Ministry for Environmental Protection and Regional Policy (HMERP), approximately sixty fuel and oil storage tanks were removed, and 72,000 cubic meters of contaminated soils were excavated and biologically remediated.

In most cases, one growing season (April to September) was sufficient for the total petroleum hydrocarbon (TPH) concentration in the soil to reach the cleanup limit of 100 parts per million (ppm) which was the limit prescribed both contractually and by the local regulatory authorities in the two regions. In the case of some of the more contaminated, less air-porous soils at Veszprém and Tab, 1.5 to 2.0 entire growing seasons were required. Soils reached the cleanup limit and were certified as clean in several phases, spanning between October 1992 and December 1993; all of the soils were certified as clean in 1993. Subsequent to closure sampling and certification of the attainment of the cleanup level, soils were backfilled to their original locations, and the sites were turned back over to the Hungarian State Property Agency, or in the case of the Veszprem Kossuth Base, to its new owner, the Municipality of Veszprem.

This experience demonstrates that bioremediation using the landfarming technique is a cost-effective solution for soil remediation, and it works even with stringent cleanup limits. This technology is relatively inexpensive. Additional savings can be realized at vacated bases in Eastern Europe due to the lower cost of labor and the abundance of wide-open, paved surface areas which are ideal for constructing landfarming parcels at most military sites. Furthermore, the current work provides evidence that biostimulation can be effective under certain circumstances, resulting in further monetary savings, and should be seriously considered as a possible alternative to bioaugmentation.