A state study of the proposed realignment of Trent Avenue has found soil and ground water contamination at several old industrial sites on the south bank of the Spokane River.
The polluted sites are in a half-mile corridor between the Riverpoint Higher Education Park and the James Keefe Bridge.
They include a former rail yard, a defunct tar company and a coal gasification plant that closed in the 1940s.
State and federal officials already knew there were pollutants in the ground at the site of the old tar and coal plants.
But the Department of Transportation study, completed Nov. 14, is the first to survey the entire industrial corridor where Trent Avenue could be rerouted by 2002.
Trent cuts through the 48-acre Riverpoint campus, and administrators are pushing for it to be moved south before thousands of new students arrive in the next decade. The project would cost $15 million.
The pollutants include petroleum hydrocarbons, organic chemicals and heavy metals, according to the Department of Transportation study.
Some of the industrial discards have seeped 15 to 20 feet into the ground, reaching the southern edge of the aquifer - the sole source of Spokane’s drinking water - near the James Keefe Bridge, the study found.
The pollution, however, hasn’t reached the city’s drinking-water wells, state and city officials say.
“We tested the nearest city wells and came up zero,” said Jim Prudente, regional environmental manager for the Department of Transportation.
Investigators now have to determine how far the pollution has spread, Prudente said.
One of the sites represents another environmental headache for Washington Water Power Co., which recently spent $13 million to contain a 75,000-gallon oil spill from its defunct downtown steam plant.
The new site that must be cleaned up is on land now owned by Brown Building Materials at 111 N. Erie. The property is near the Spokane River and over the southern boundary of the aquifer.
Most of the property belonged to a plant that turned coal into natural gas, a facility operated by Spokane Natural Gas Co. from the 1890s until 1948.
In 1958, WWP merged with Spokane Natural Gas and bought that property and their other assets, WWP spokesman Rob Strenge said.
“We didn’t use it for anything and sold it to the Brown family in 1978,” he said.
Contamination was also detected on the southwest portion of the Brown property on land leased from Burlington Northern Santa Fe Railroad. The land was occupied by Betts Roofing Tar Co. until the 1930s, when the company became American Tar Co.
The company refined coal tar from the coal gasification plant and made creosote, road tar and pitch. The property is already on the state’s hazardous waste cleanup list as “awaiting remedial action.”
The new state study found high levels of hydrocarbons in the soil and ground water at the Brown Materials site, and lower concentrations of volatile organic chemicals and heavy metals.
“The high-concentration contaminants are typically found at depths greater than five feet below surface,” the report states.
WWP has been working with state and federal environmental agencies to monitor the pollution, Strenge said. The company is spending $100,000 for test wells and lab work at the site.
“We knew we had a continuing liability as the former property owner,” he said.
When the Transportation Department was looking at the site as part of the Trent realignment, WWP contributed $50,000 toward the first phase of the $300,000 environmental study, Strenge said.
The utility is putting in several ground water test wells this week at five locations on the North Erie property to check further for contamination detected by Emcon, the Spokane consultant hired to do the state study.
“Based on Emcon’s results, we need to take a closer look at ground water,” said Hank Nelson, WWP’s environmental compliance coordinator. “Before the end of the year, we ought to know the water dynamics down there.”
There are 1,500 former coal gasification plants in the United States. All were located next to rivers, and many have required extensive environmental cleanups, Nelson said.
That usually involves removing contaminated soils down to the ground water, erecting a barrier to prevent tar from entering the river, and installing pumps and a monitoring well to track pollutants.
The Trent corridor study has been submitted to the state Department of Ecology, which oversees Washington’s strict toxic cleanup laws.
The contamination won’t halt the Trent realignment, but it can’t be ignored, experts say.
State law requires current and former owners of contaminated land to help pay for the cleanup. In addition to WWP, others already cooperating to solve the Trent pollution problems include the city of Spokane and Riverpoint Higher Education Park, Prudente said.
“There’s a good chance we can get in there and do what Ecology requires us to do (before) the design and construction of the Trent realignment,” WWP’s Strenge said.
A detailed look at all the corridor’s environmental impacts should be completed by next July, Prudente said.
If the state decides to move the road and can find money for it, construction on the Trent bypass could begin in 2001.
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