Hydraulic Cut-off Wall at Market Street - Seattle, WA

A funnel and reactive iron gate cut-off wall system was installed for this project. The system was desgined for treatment of chlorinated solvents in groundwater adjacent to and underneath an Burlington Northern Railroad right of way. This challenging project was located in a sensitive area, 200 feet north of the Lake Washington Ship Canal and adjacent to the Ballard Ship Locks, the third most popular tourist destination in the city.

The project site was located on a city block previously used for metal anodizing, painting and light manufacuring. Chlorinated solvents such as tetrachloroethylene (PCE), trichloroethylene (TCE) and vinyl chloride (VC) were detected at depths of 32 feet in ground water beneath the site. The objective behind installing the remediation system was to treat the impacted water as it migrated down gradient from the contamination source area. The remedial system consisted of a 325 foot long wall, which included two 45 foot long, permeable gates filled with reactive iron sand mixture. A 100 foot long section of the Burlington Northern railroad line and electronic gate control was removed and replaced.

Project Performance

The successfully completed project was the first of its kind in Washington State. A letter of commendation was received from A&B Jacobson that stated in part, "The crew was very competent… Jacobson would highly recommend..."