There are two hazardous materials, petroleum and trichloroethylene (TCE), which have been identified at a twelve-foot depth, in concentrations which exceed state and federal maximum levels, according to Utah Department of Environmental Quality scientist Mark Novak:
Novak said the city's second round of soil and groundwater tests showed petroleum concentrations as high as 520 parts per million. The regulatory limit is 10 parts per million. Concentrations of tetrachloroethylene, a solvent used in dry-cleaning and metal degreasing, were as high as 13 parts per billion, more than twice the limit.In other words, a third round of tests has now been demanded by the DEQ, and the agency isn't quite ready to give the Rec Center project the "thumbs up" -- at least not until the real tests have been performed and evaluated. They're going to have to drill deeper, as the headline says.
Not knowing how to interpret John Wright's new data, I put in a call to a scientist friend that I mentioned in the comments to another article, and spent about 30 minutes discussing the situation with him this afternoon. My friend has been employed as an environmental quality scientist in the State of Florida for most of his post-collegiate adult life; and I regard him as an expert on the subject. I asked him whether any conclusions could be reasonably drawn from the information contained in the two newspaper articles. I'd already emailed the earlier Kristen Moulton article, and we went over John Wright's article over the phone.
The short answer: No final conclusions can yet be drawn solely from the data in the two articles, except that a serious contamination problem can't yet be ruled out, without more information. On the other hand, high TCE levels at twelve feet creates a high probability that higher TCE concentrations may exist deeper in the ground, and this could be the "tip of the iceberg," in the words of my expert, for the following reasons:
The problem with TCE relates to its unique physical properties, he explains. It's liquid, heavier than water, and quite volatile. It can cause lots of peculiar problems once it's leaked into the soil. What happens is that it drains with gravity through the soil until it meets an impermeable barrier layer like rock, where it will either continue to flow downward and laterally -- if there's a downward slope -- or start forming an underground pool, if it comes to rest on a flat or concave underground surface. If it forms such a pool, then it exhibits another property -- volatility. Once it starts to pool up, it begins to evaporate (just as water does at room temperature,) and will permeate the soil again as a gas, moving both upward and outward. After that, it will again condense and return to a liquid state, where it will again pool up, once it drains through the soil to an impermeable layer. The process repeats over and over again over time, and a fairly localized spill can thus saturate and contaminate the soil and bedrock in a wide area around the original spill.
Two other physical properties, toxicity and oderlessness, are the real problem. The stuff can't be detected by odor, (by the human olfactory system,) even when it's reached harmful levels. Here the substance's volatility comes into play again. The tiny TCE molecule can even permeate relatively porous concrete foundations when in gaseous form, and cause serious health problems to occupants of buildings located on TCE-contaminated sites.
It's nasty and tricky stuff, according to my friend, the expert.
My friend just laughed when I asked whether the problem might be resolved before the end of the year mall project "drop-dead date." He explained that the environmental quality cops are really wary of TCE right now, and the perceived danger level keeps rising as the scientific data flows in. "Don't expect Utah DEQ officials to go easy on the Ogden City project just because of a tight time-line." he said.
The good news: the oil contamination is apparently no big deal. It can be cured by simply hauling off all the contaminated dirt.
And more good news! The "brownfield" designation that Ogden City officials seek will be very helpful in the long-run, my expert says, if the mall-site turns out to be environmentally dirty. The EPA has lots of federal money available for site cleanup, as long as Ogden City doesn't mind waiting in a very long line. That's what many other cities like Ogden are doing right now, he adds. The Feds are somewhat serious about TCE cleanup, I guess.
There it is, for what it's worth.
Oh yeah. There's one more thing. There's even a blog that's dedicated to discussing TCE contamination. The Ogden situation is even mentioned there, too. I haven't had time to check it out myself; but maybe some of our gentle readers would like to do so.
Comments anyone?
Update 9/06/05 -- 10: 24 a.m. MT: Please take note that I've added The TCE Blog, (the blog mentioned in the preceding paragraph,) to the Weber County Forum National Blogroll, which is located in the right sidebar. You'll find an abundance of information on TCE contamination there. As an added bonus, you'll find that a new article, concerning Ogden City's situation, has been posted there today, along with a very gracious welcome to all Weber County Forum readers.
