On-Call Contaminated Materials Management


Client: Tulalip Indian Tribe & the City of Everett (Joint Board)
partners: Parametrix & MWH Americas, Inc.

Pre-design water quality monitoring.

Pre-design water quality monitoring.

View of Segment 2 installation through the Lowlands Cleanup Area.

View of Segment 2 installation through the Lowlands Cleanup Area.


The Joint Board contracted the Parametrix and MWH Americas, Inc. (Team) to provide an 8-mile water pipeline connecting the City of Everett water distribution systems to the Tulalip Tribe’s water system. The project involved the installation of 36-inch and 48-in diameter steel water transmission pipeline in several segments. The Joint Board and Team selected Pacific Stormwater to provide material handling expertise to prepare for and mitigate known contaminated media located adjacent to portions of the pipeline.


Segments 2 and 3 of the pipeline were located within the Everett Smelter Lowlands Area, currently under remediation by Department of Ecology for extensive soil and groundwater arsenic contamination. The contamination impacted both the design and the construction of the project as well as soil, surface, and groundwater impacted during construction resulting in special handling and disposal requirements as specified by Pacific Stormwater.  


To begin, an exhaustive review of historical documents and analytical data was completed. Identified data gaps were investigated through soil and groundwater investigations in conjunction with Ecology and in coordination with BNSF Railroad. Pacific Stormwater was responsible for providing technical specifications and guidance to the Team for inclusion in the construction documents. Pacific Stormwater solicited solid waste, hazardous waste, and water treatment vendors to find a cost-effective solution for disposal of contaminated construction spoils. Pacific Stormwater was responsible for identifying contaminated areas along the proposed pipeline route, and for providing material handling specification on 60%, 90%, and final design documents. Additional Technical Information Reports were submitted to internal and external stakeholders to facilitate project coordination and advance the schedule.


• Historical Research
• Environmental Review and Documentation
• ROM Cost Estimates
• Regulatory Agency Coordination


• Soil and Groundwater Quality Sampling
• Water Tightline System Design
• Surveying
• Technical Information Reports
• Construction Ready Plans


• Soil and Groundwater Investigation
• Soil and Groundwater Quality Sampling
• Performance and Compliance Monitoring and Reporting