In Situ Soil Neutralization and Stabilization
Trihydro implemented a cost-effective in situ soil neutralization and stabilization system to address residuum and low pH conditions at an active refinery corrective action management unit.
Due to the co-mingling of spent sulfuric acid, Trihydro identified widespread residuum and low pH conditions at an active petroleum refinery in southern Wyoming. The client tasked our team with evaluating the efficacy of an in situ soil treatment solution using industrial byproducts compared to the excavation and disposal of the contamination in an onsite corrective action management unit.
Trihydro’s evaluation of in situ neutralization and stabilization and initial pilot testing showed that soil pH could be increased to about 5 by mixing a 20% volume of a neutralizing agent. We identified precipitated calcium carbonate (PCC) as a potential neutralizing agent. Our team tested PCC, which is a non-reusable byproduct from sugar facilities, at pilot-scale and selected it as an effective and financially beneficial neutralizing agent for the acidic soils.
In addition to neutralizing the acidic soils, we mechanically stabilized in place the asphaltic wastes/free residuum to reduce its mobility in soils. Our team undertook stabilization by mixing impacted site soils with material from the surface (e.g., PCC, Portland cement, fly ash, or onsite soils) using an extended reach track hoe.
