StanTech conducted a remedial investigation, prepared specifications for waste stabilization, and supervised the remedial project. StanTech provided continuous consultation, performed field observation and testing activities, coordinated with ODEQ personnel, and provided assistance to legal counsel for hydrocarbon waste/acid sludge pit remediation, including RCRA waste characterization, neutralization, stabilization, and monofilling. StanTech continues to provide post-closure monitoring services to the client.
Unknown parties illegally discharged what are believed to have been petroleum exploration and refining wastes in this rural pond. Floating hydrocarbons and low pH water and sludge comprised the most obvious environmental threat.
Preliminary cost estimates consisted of a proposed multi-million-dollar contaminated media removal and off-site disposal work scope. StanTech was subsequently retained to perform an alternative lower cost solution. The project Remedial Action Plan (RAP) was approved by the regulatory authority, and consisted of three phases:
Phase 1 -Neutralization of Acid Utilizing Lime Slurry
A work plan and site Health and Safety Plan were prepared, and engineering calculations were performed to determine lime quantities and application rates. Neutralization was successful in eliminating the hazardous characteristic (corrosivity) which had resulted in the initial classification of the wastes as hazardous under RCRA Subtitle C. Following this step, it was possible to execute site remediation under Oklahoma Special Waste and RCRA Subtitle D regulations.
Phase 2 – Treatment and Land Application of Pond Water
Pond water was treated and land applied, pursuant to an ODEQ land-application permit.
Phase 3 – Construction of a Clay-Lined Monofill
Monitoring wells were constructed to define soil and groundwater impact. Sludge samples were collected for bench-scale bearing capacity testing using various Type C fly ash and Type I Portland cement mixtures. Based upon these results, treatability studies were performed, and a mixture was selected which passed TCLP (Toxicity Characteristic Leaching Procedure) analysis. Waste was then stabilized, monofilled, and capped.
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4300 N. Lincoln Blvd.
Oklahoma City, Oklahoma 73105-5106
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