At a glance
Location: New Jersey
Geology: Coarse (sand/gravel)
Contaminant(s): Light petroleum
ETEC Solution(s): CBN, PetroBac, DO-IT system
Unique challenge(s): Ecologically sensitive area, Under structure
The site consisted of a large, thick heating oil plume that extended underneath an existing structure. The site was located within an area with very stringent groundwater standards.
Our core petroleum hydrocarbon remediation solution, including Custom Blend Nutrients (CBN™) and our PetroBac™ Stimulant Bundle were used. The bioremediation products were delivered using our 10-gpm Dissolved Oxygen In-situ Treatment (DO-IT™) equipment through horizontal wells underneath the structure.
Within 18 months of active remediation, soil and groundwater cleanup goals were acheived. An unrestricted No Further Action (NFA) was issued and the regulatory case closed within 24 months following the treatment.
Site conditions and remedial goal
The site consisted of a heating oil plume that extended underneath an existing structure. The target treatment area was approximately 3,500 square feet with a saturated thickness of 11 feet.
Lithology in the impacted zone consisted mainly of sand. Free product was assumed to exist below the structure.
Due to the site's location in the NJ Pinelands, the Groundwater Remediation Standard (N.J.A.C. 7:9C-1.7(b)) for monitored organic compounds was the Practical Quantitation Limit (PQL) and was the background concentration for monitored inorganic compounds (nitrates and sulfates included).
Our core products for petroleum hydrocarbon remediation: Custom Blend Nutrients - CBN™ (macro-nutrients, micro-nutrients, and electron acceptors) and our PetroBac™ Stimulant Bundle (enzymes and bacteria) were used for the project.
A 10-gpm Dissolved Oxygen In-situ Treatment (DO-IT™) System was used to deliver the bioremediation products using horizontal wells underneath the structure. This is how the process worked:
- Groundwater was extracted from four extraction wells (shown on the figure as EX-1 through EX-4).
- It was automatically amended with 45-ppm dissolved oxygen, CBN™, and PetroBac™.
- Then it was distributed into the subsurface via 5 horizontal injection wells (IW-1 through IW-5).
Over 4 million gallons (gal) of groundwater were recirculated in 18 months and amended with 1,500 pounds of dissolved oxygen, 7,600 pounds of CBN™, and 200 gal. of PetroBac™. Following 18 months of active remediation, the following goals were achieved:
- PQL concentrations for organics in groundwater
- Natural background concentrations for inorganics in groundwater
- 5,100 mg/kg Extractable Petroleum Hydrocarbons (EPH) in soil
Within two years of starting the remediation, the NJ Department of Environmental Protection issued an unrestricted No Further Action and Covenant Not to Sue determination, closing the regulatory case.