WORK PLANS FILE 2 - Laserfiche WebLink

Home Browse Search

20 October 2011 AGE-NC Project No. 96-0236 Page 4 of 7 Duration (and cost)of enhanced bio-remediation is dependent on the volume of saturated soil and water to be remediated, the number of injection points/wells, the average concentrations of contaminants and nutrients, ground water gradient, and the permeability of soil. Theoretically, the radius of influence of the injection points should increase rapidly at first, then gradually decline as the affected volume increases and the ORC-advanced ® media encounters decreasing hydrocarbon concentrations toward the margins of the hydrocarbon plume. Shorter-chain hydrocarbons are typically consumed first and longer- chain hydrocarbons later. ORC is considered to be a moderately favorable remedial alternative for the site. However, ORC does not appear to be the best available technology based on the following: • Enhanced bio-remediation is dependent on the natural bio-substrat set, already active on the site. • Remediation at sites with similar soil compositions and hydrocarbon-impact typically takes between 24 and 48 months. • Adsorbed and dissolved concentrations at the site would generally require an initial dose of a stronger oxidant to reduce concentrations to levels where ORC can treat the plumes. • A large number of borings and several treatments would likely need to be performed to achieve cleanup goals. • Additional monitoring costs would be incurred to track the progress of the injections, driving up the overall cost to complete the project. 4.0. SELECTION OF REMEDIAL TECHNOLOGY 8t SCOPE OF WORK Based on the above evaluation of remedial technologies, it is AGE's opinion that the most applicable technology to remediate residual"drowned", hydrocarbon impact to soil and the core of the dissolved plume is a form of Fenton's Reagent. Prior to design of a full scale remedial action plan, AGE is recommending performance of a limited ISCO pilot test utilizing a solution of 5% hydrogen peroxide and common muriatic acid. Results from the pilot testwould be used to evaluate the overall performance of the selected technology and to design a full scale application plan of the proposed media. For the pilot test, AGE proposes to apply a hydrogen peroxide and acidified solution to the area surrounding the former under ground storage tank area near well DPE-1 and MW-1 A/B and east near well DPE-2, to evaluate the response of the ground water to ISCO remediation. The proposed solution is proposed to be applied to wells DPE-1 and separately to well DPE-2, by gravity injection techniques. Advanced GeoRnvironmental,Inc.