At a glance
Location: Mississippi
Geology: Coarse (sand/gravel)
Contaminant(s): Naphthalene, PCPs
ETEC Solution(s): CBN, DO-IT system, FeSolv
Unique challenge(s):
Site Summary
At a former wood treatment chemical manufacturing facility, the scale and challenging nature of the site resulted in a Federal Superfund designation. The chosen solution was to install two Dissolved Oxygen In-situ Treatment (DO-IT™) systems to recirculate and oxygenate groundwater along with ETEC's bioremediation amendments. Groundwater cleanup targets have been achieved for half of the site, with fantastic progress ongoing for the remainder of the site.
Site conditions and remedial goal
At a very large site formerly used as a wood treatment manufacturing facility, there were several unique challenges:
- Naphthalene and pentachlorophenol were detected at maximum concentrations of 7,290 µg/L and 112 µg/L, respectively
- Contamination extended over a very large area
- Significant volume of contaminated groundwater
- Sensitive human occupation and ecological surroundings
The significant and unique challenges led to the site's Federal Superfund designation.
ETEC Solution
Two 50-gpm Dissolved Oxygen In-situ Treatment (DO-IT™) systems were used to recirculate and oxygenate groundwater in the three areas. A total of 28,000 lbs of dissolved oxygen and 11,300 lbs of CBN nutrients were applied, including 6,780 lbs of nitrate and 5,080 lbs of nitrogen.
Two separate groundwater recirculation cells were used to control the distribution of oxygen, nitrate, and nutrients. The average flow rate was 30 gpm. A total of 96 million gallons of groundwater was recirculated over 71 months. Other operational milestones include increasing groundwater dissolved oxygen to 28 mg/L, raising the groundwater pH, and combating iron and mineral fouling with ETEC's Fe-Solv mineral sequestration product.
Remedial outcome
The site remains active. So far, Areas 1 & 2 have achieved groundwater cleanup goals and are in a monitoring phase. Area 3 continues to recirculate, but is on track to cleanup goals.