William R. Mahaffey¹, Ronald D. Resseguie¹, Charles M. Mickel²

(1) Pelorus EnBiotech Corporation, Evergreen, CO
(2) Pendergast Sarni Itell Environmental Management, LLC, Golden, CO

ABSTRACT: Application of Fenton's Based Chemical Oxidation to Chlorinated Pesticide Impacted Soil

Chemical oxidation technologies (CHEMOX) are in increasing use for the restoration of contaminant impacted aquifers. Most in situ applications target petroleum hydrocarbons released from leaking UST's, and chlorinated solvent impacts primarily chloroethenes (i.e., PCE, TCE, and the DCE isomers). However, there is a wide range or organic pollutants that can be safely oxidized to harmless by products using the appropriate chemical oxidants. This paper will discuss some of the chemical oxidants currently available for environmental restoration and the typical application mechanisms. In addition a case history will be presented for a site impacted with DDT, DDD, DDE, Dieldrin, and other chlorinated pesticides.

The site is a former tree farm that stored and used large quantities of chlorinated pesticides from 1946 through 1970. Chlorinated pesticide impacts ranged from 100 - 28,000 ug/Kg for DDT and 10 -2000 ug/Kg for Dieldrin. The DDT and Dieldrin cleanup levels acceptable for industrial site use are 2.2 ppm and 0.03 ppm respectively. Using a Pelorus EnBiotech Corporation procedure called the ACRS (Appropriate Chemox Reagent Selection) process, a program was designed for applying a proprietary Fenton's reagent formulation to the approximately 10,000 sq. ft. area of impacted surface soils.

After grubbing and tilling of the top 12 - 18 inches of soil, stabilizers, enhancers and reagent catalysts were applied and mixed into the soil. Soil moisture was adjusted to an optimal content using standard irrigation and watering equipment immediately prior to the injection of hydrogen peroxide into the surface soils. After the first application 50 % of the treatment area met or exceeded treatment goals with DDT and Dieldrin levels at or below the standard.

AAPG Search and Discovery Article #90906©2001 AAPG Annual Convention, Denver, Colorado