International Dredging Review

International Dredging Review

Hart Crowser Inc. will provide consulting and design services to Occidental Chemical Corporation and the Port of Tacoma Washington for the proposed $20 million to $25 million Phase I cleanup of the outer Hylebos Waterway in Tacoma.

The project will be the third major cleanup in the Commencement Bay Nearshore Tideflats since the bay was declared a Superfund site in 1981. Hart Crowser has provided design services for all three projects including the Sitcum Waterway (for the Port of Tacoma) where work is still underway. If approved bye the U.S. Environmental Protection Agency the Hylebos project could begin this year and be completed in 2002.

This is an important project with many benefits” said Philip Spadaro Hart Crowser’s Director of Port and Harbor Services. “Moving forward with Phase I cleaning up the mouth of the Hylebos – is a significant step toward cleaning up the rest of the waterway will benefit Commencement Bay as a whole and will allow the Port to make effective use of Slip 1 while furthering its strategy for marine terminal expansion” he said.

Plans call for contaminated sediments in the Hylebos to be dredged and deposited in the Port’s Slip 1 facility at the north end of the Blair Waterway. The dredged material will be placed in a nearshore confined disposal facility (DCF) which will be covered and sealed with a thick cap of clean material and pavement. Hart Crowser provided similar services in the previous cleanup of the Sitcum Waterway for which dredged material was deposited in the Milwaukee Waterway and then paved over for use as a container terminal storage area.

On the current project Hart Crowser will design both the dredging proposed for several areas in the Hylebos Waterway and the CDF. The primary goals of the dredging design will be to remove contaminated sediments while maintaining the stability of existing waterway structures and limiting water quality impacts on the surrounding environment. The dredging design will also target the most efficient and cost-effective mode of sediment removal and transportation to the disposal site.

Primary objectives for the proposed nearshore CDF are to contain the dredged material prevent releases to the surrounding environment by providing a structurally sound storage facility and facilitate future container terminal expansion at Slip 1 on top of the completed CDF.

The project addresses the Puyallup Tribe’s concerns regarding the scope of the cleanup and is responsive to issues raised by Citizens for a Healthy Bay as well as concerns by other members of the public. The plan helps ensure that the Port of Tacoma will remain competitive and a vital part of the local economy well into the 21st century. The Hylebos cleanup and Slip 1 terminal expansion are important components of the Port’s strategy for increasing container terminal capacity in both the long and short term.

Founded in 1964 Hart Crowser is an environmental consulting and remediation engineering and design firm headquartered in Seattle with offices in Portland Oregon; Anchorage Alaska; Long Beach California; Denver Colorado; Chicago Illinois; Boston Massachusetts and Jersey City New Jersey. The firm’s sediment services division has completed more than 100 major projects for clients that include the U.S. Navy and ports shipyards marine terminals and waterfront industries of all types on the West and East Coasts.