Voluntary Remediation Program – Industrial Site

The challenge:

A facility formerly used to manufacture staplers and staple components covers a city block and is surrounded by residential, commercial, and industrial buildings. Paints, thinners, solvents, and cleaners were used as part of the manufacturing process. The source is suspected to be an unlined sump in the center of the basement. The client wanted aggressive remediation of the site to avoid the long-term cost of leasing the basement area from the new owner while slower remediation methods were employed.

The GES solution:

Site investigation activities formed the basis for an effective and versatile remediation action workplan to collect soil and groundwater for treatability tests and refine the contaminant distribution. A membrane interface probe (MIP) was used to log volatile organic compounds in the subsurface. An electrical conductivity system was used to classify soils. A combination of physical and chemical in-situ remediation technologies were applied to aggressively treat each of the four zones in the impacted area: soil vapor extraction (SVE) followed by ambient air and ozone sparging, and potassium permanganate injection. The mass of recovered vapors included 165 gallons of TCE. Dissolved-phase potassium permanganate consumption was greater than 90% throughout the majority of the treatment area at five months after injection. Dissolved-phase TCE concentrations showed reductions of 83% - 99%.

The benefits:

The use of leading-edge investigative and remediation technologies saved the client over $1 million in lease payments in comparison with the more conservative approach taken by others. Future strategies include continuing operation of the low-flow SVE and ozone sparging system, targeting remaining “hot spots” in the tool and electric room, evaluating dosages for other areas, and implementing off-site remedial actions.