Pinning It Down: Mapping an Underground Legacy from an Industrial Past

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The next phase of finding and cleaning up groundwater plumes under our urban campus begins July 27 with the drilling of wells.

Buried deep below the restored historic warehouses that today house classrooms and labs of UW Tacoma lies a historic legacy that must not be preserved: contaminated groundwater. Just as state-of-the-art architecture and community planning have been applied above ground since construction on the UW Tacoma campus began in 1995, a tremendous level of environmental expertise has been applied to tackle contaminated groundwater and soil below ground that originated more than 100 years ago. This underground environmental work began in 1997 when the University of Washington entered into a voluntary legal agreement with the state Department of Ecology to coordinate efforts to identify the extent of contamination so that it can be cleaned up. From July 27 through August drill rigs will appear on and around campus.  Pictured: crews digging a groundwater monitoring well near The Rock restaurant.

The next phase of the saga has begun. Drilling for monitoring wells starts July 27 and continues through August at several locations near and on the UW Tacoma campus. Neighboring residents and businesses can expect drilling noise and traffic control during work hours from 9 a.m. to 4 p.m. Monday through Friday. Work within the UW Tacoma campus footprint could begin as early as 7 a.m.  Drilling at each well location is expected to last no longer than two days.

During previous phases of the project, groundwater was tracked uphill to the campus border, which is marked by Tacoma Avenue to the West, 21st Street to the South and 17th Street to the North. The next phase looks off campus for the first time to understand the extent of plumes and determine whether any sources continue to feed hazardous materials into the ground.  Several wells will be drilled between Tacoma and Yakima avenues in the area uphill from campus. For details, see the Ecology website for the project.

The project turns the next page in a clean-up story that dates back more than 20 years.

“Back when the first phase of campus construction was underway in the mid-1990’s, some contamination was identified in one of our parking lots, so we did what you always do in those situations - we called on the experts at the Department of Ecology to guide our effort to clean it up,” says Dave Leonard, Director of UW Tacoma’s Environmental Health and Safety Department. “What we soon learned was that soil and groundwater contamination from businesses that were in the area many decades ago was not only in that parking lot, but different types of contamination was in the groundwater in areas across the campus footprint.”

In the environmental-cleanup playbook, the game begins with identifying the extent and source of contamination before you invest money in cleaning it up, otherwise the contamination might return after the cleanup work is done.  

Determining the shape and size of a groundwater plume is like sticking pins in a map. First, you drill a hole deep into the ground, create a little well, and pull samples of groundwater. If you find a chemical it’s a “hit,” so you place a pin on the map that provides a clue about where to drill the next well. After a series of hits and misses, you begin to learn the shape of the plume, which you follow until the extent of contamination is known. To do this properly requires environmental specialists, university staff in the Environmental Health and Safety Office in Seattle and Tacoma, along with hired consultants and project staff from Ecology, who have extensive training and experience in the field. The process is time-consuming, so the game plays out over years.

Back in the late 1990s, it became clear the contamination was fairly extensive and coming from multiple places. Because of this complexity, the university voluntarily entered into an “Agreed Order” with EcoloWork to identify and map a groundwater plume beneath the UW Tacoma campus began in, which is a legal document that lays out the rules and timelines for how the analysis of contamination will be done. One consideration in dealing with contamination deep in the ground is the potential for risk to human health, which in this case is very low and has been carefully monitored over time. Another concern is the potential for these contaminants to reach the Foss Waterway and Commencement Bay. Testing to date has shown contaminants may be heading that way very slowly, but they haven’t reached there yet.

“The explanation is that while groundwater may move quickly downhill, the chemical contaminants in the groundwater are ‘sticky,’ which means they move very slowly, but they do move downhill,” says Leonard.  “A major objective of the project is to keep these plumes of underground chemicals from eventually getting to the Foss Waterway, a former Superfund site downhill from campus that was successfully cleaned in 2006 after years of work by the City of Tacoma, Ecology and other partners.”     

Meanwhile, the eyes of those playing this environmental game of cat and mouse on the UW Tacoma campus have been gradually expanding their investigation uphill.

Groundwater knows no boundaries and the plumes found under the UW Tacoma campus are no exception. Phase one showed the groundwater plumes are flowing onto the campus from higher ground, so the research needs to move uphill beyond the campus border. A new Agreed Order finalized in May guides the process of investigating off campus.

Ecology has a playbook for these situations as well, which is based on state law. In the legal language of the Agreed Order, UW Tacoma is called a Potentially Liable Party (PLP) because it owns land where contamination was found, even though it didn’t cause the pollution. Because the investigators are tracking down contamination found at UW Tacoma, the university is required to pay for this part of the investigation as it moves uphill beyond its property, which it does the with funds provided through the state legislative process.  The City of Tacoma, as a partner in the project, allows wells to be drilled at the edges of city streets. As contamination is found on other properties, the owners may or may not play a role in how the investigation and cleanup proceed. 

Creating the new Agreed Order involved providing opportunities for public input. The Department of Ecology conducted a public outreach program that included contacting owners of property near where wells will be drilled, a public meeting and an open comment period that ran March 17 through April 18. During the week leading up to drilling, Ecology sent postcards to property owners and knocked on doors to inform residents and businesses about the project. Outreach to news outlets resulted in a story on KOMO TV and updates in several media outlets.

“The process that is playing out in this part of Tacoma has taken place in other communities across the state. Here in Tacoma, our objective is to protect the Foss Waterway and eliminate any potential risk to health,” says Leonard.     

Written by: 
Mike Wark / July 22, 2016
Media contact: 

Mike Wark, UW Tacoma External Relations, 253-692-5771 or