Soil and Groundwater Remediation at Pier A West, Wilmington, CA
The Port of Long Beach acquired a 90-acre oil field and intended to develop the property for future beneficial use; however, the property has to be cleaned up before development. Oily wastes were buried in 19 sumps in the 1950s. Groundwater contaminated with chlorinated solvents and petroleum hydrocarbon compounds were found in two isolated plumes. Accord Engineering played a critical role throughout the entire design phase of the contract. Our professional staff provided consulting and design services to assist with the project needs in terms of conceptual and detail design and bench and pilot testing since 2004.Bio-augmentation and chemical oxidation technology were considered to remedy the groundwater which contains high concentrations of chlorinated solvents, especially vinyl chloride. Accord Engineering is currently conducting a pilot-scale chemical oxidation test in the field using sodium permanganate, ozone gas, and hydrogen peroxide. Our engineers have developed a unique approach to apply the oxidation agents to avoid costly vapor recovery near ground surface using soil vapor extraction technology.
Installation of chemical injection and groundwater monitoring wells were performed using a Mobile B61 hollow stem drill rig and a tracked rig because of the soft and muddy ground. Photo ionization detectors and drager tubes were used to monitor the volatile organic compounds and vinyl chloride, respectively, in the breathing zone. When the vinyl chloride concentrations exceeded the pre-established threshold in the Health and Safety Plan, the site level was upgraded to level C.
During the chemical oxidation pilot test, a total of 120,000 lbs of sodium permanganate will be injected into the first shallow aquifer and the clayey layer using direct push technology. Ozone gas and hydrogen peroxide solution will be injected into the second aquifer using 20 well points. This pilot test will last approximately 6 months. Extensive groundwater and soil vapor monitoring will be conducted during the test.
