TOSC finds flaws in Xcel contamination study

Company says TOSC misunderstood its report

Steve Tomasko - The Daily Press
Last Updated: Wednesday, July 11th, 2001 11:26:53 AM

An independent review of two Ecological Risk Assessments of the Ashland lakefront contamination site has found fault with the study performed for Xcel Energy.

The report concludes a Department of Natural Resources ERA is valid in showing likely ecological impacts from contamination and that the Xcel Energy-sponsored report contained errors in calculations rendering its conclusions invalid.

The report comes from the Technical Outreach Services for Communities based at the University of Michigan. TOSC is a U.S. Environmental Protection Agency-funded organization that provides technical expertise to communities with environmental problems.

TOSC was called in by the Ashland/Bayfield County League of Women Voters and the Lake Superior Alliance to provide independent information to the community about the contamination issue.

Xcel disagrees with the conclusions of the TOSC report on several points.

The two ERAs TOSC studied were a report produced by Short Elliot Hendrickson, Inc. for the DNR and one by Dames and Moore for Xcel. Both are engineering firms.

Although based on the same data, the two ERAs came to different conclusions on the extent of the contamination and its effect on organisms in Lake Superior.

The SEH report concluded that the area of impact in the bay would be large and natural recovery is unlikely. The D&M report concluded that a smaller area would be affected and natural recovery would be possible.

The TOSC review of the ERAs was authored by Christopher Marwood, a specialist in PAH toxicity at Miami University in Oxford, Ohio. PAHs are the main contaminants at the lakefront site.

Marwood said the D&M report used a mathematical model to determine the effects on biological organisms in the portion of the bay contaminated with PAHs.

However, he said, D&M did not use the model correctly.

"A careful examination of the D&M calculations revealed several deviations from the model and mathematical errors in calculations. When the calculations were performed correctly, the model estimated substantial toxicity to organisms from PAHs in all but a few sediment samples, a result similar to SEH's findings," Marwood wrote in the summary of his review.

Marwood also found that the SEH study more closely adhered to the structure suggested by the U.S. EPA Guidelines for ERA, while the D&M assessment was missing important sections of the analysis and risk characterization.

Jim Musso, Xcel siting and land rights manager, disagrees with the TOSC conclusions.

"TOSC really misunderstood what Dames and Moore's role was. We never purported this to be an independent ERA," Musso said.

Their report was simply a response to the SEH report, he said.

Musso said their report found flaws in the SEH study that were consistent with EPA's criticisms of SEH.

For example, D&M concluded the SEH study improperly extrapolated the results of a small data base to the whole contaminated area.

"We feel that was a critical error that was never acknowledged by TOSC," Musso said.

The company also said the SEH study was based on samples and species not representative of Chequamegon Bay.

Despite the feuding reports, Musso said Xcel will continue working with the DNR, EPA and the City of Ashland on resolving the contamination issue.

Marwood said the issue of a small data base was a "minor" flaw in the SEH study, but more samples have been taken since that report came out.

He said the issue of whether the D&M study was a full-fledged ERA or just a response doesn't matter in his review.

The review "was not on the basis of whether they were doing a full assessment," Marwood said. "The fact is, the science they used was flawed."

Jamie Dunn, project leader for the DNR said he was happy to see the TOSC review. He said it was similar to their response to the D&M report.

League of Women Voters president Kathy Allen said the TOSC review helped to clarify things in her mind.

"Its good to get an unbiased review from scientists in the academic world that didn't have any connection with either party," she said. "That's not to say anyone was good or bad. But it adds another piece of information the public can use."

TOSC director Kirk Riley said the review makes it clear that the ecological risk from PAHs should be taken seriously. He said TOSC will stay involved in the issue and may produce further reviews of other lakefront studies.

ASHLAND LAKEFRONT CONTAMINATION BACKGROUND

Several years ago, the DNR discovered an area on Ashland's lakefront was contaminated by coal tars.

Coal tars are a mixture of hundreds of chemicals classified as volatile organic compounds (VOCs) and polyaromatic hydrocarbons (PAHs).

The contaminated area comprises about 20 acres of lake sediments, soil and groundwater in an area between Kreher Park and the city marina.

According to the DNR, the contamination stems from at least 100 years ago when a coal gasification plant occupied the site where Xcel Energy's offices now lie on Hwy. 2.

But Xcel contends that at least some of the contamination could have come from a lumber treating operation that used to operate nearby. The contamination is consistent with cresote that was used to treat lumber, the company says.

The U.S. Environmental Protection Agency is involved in the site and is deciding whether to add the site to the National Priorities List, or Superfund list. That decision could come by mid- to late August.

More information

To see detailed copies of the TOSC review and a summary, visit their website at: http://www.egr.msu.edu/tosc/ashland or call them at: 800-490-3890.