Gunnison gets update on gas clean-up effort
By John Hales
12-12-07

GUNNISON—The bulk of last week’s meeting of the Gunnison City Council was taken up by a discussion of the current situation of the Top Stop gas leak cleanup effort.
Lance Hess, the environmental consultant hired by the city to help with remediation efforts, gave the city council an update.
Hess began by recapping the testing done for elevated levels of toxic chemicals potentially released by the gas plume underneath the city.
“We’ve performed approximately 170-180 individual tests—not locations, but tests. There’s probably five or six homes that have been evacuated either by recommendation or decisions made on the parts of residents,” he said.
In addition to testing, he said, “We’ve been working on a lot of public education.” He indicated that the great concern manifested by the community had opened the door to disseminating a great deal of information.
“Most consultants that I work with don’t know what a Summa canister is; but everybody in Gunnison knows what a Summa canister is now,” he said.
For those outside of Gunnison, a Summa canister is a device used for collecting air samples for analysis to detect levels of toxic particles and fumes.
Hess said the canvass-style testing he had been performing had “caused a stimulating dialogue on exposure levels.”
He said there was still “general angst” in the community about people not getting testing results quicker, but that he was “trying to identify the causes of some of those delays.”
Hess and the council discussed the idea of creating a website where information about the gas leak, remediation efforts and related topics could be collected. He indicated earlier this week that he hoped to have such a website up and running by week’s end.
Hess said he was continuing to test locations, even, when requested, locations outside the known impact zone of the underground plume.
“We explain where the impact zone is and ask if they’d still like a test. We’re still testing without prejudice, but it’s understandable,” he said.
Hess described a method, called a residential soil-vapor extraction system, that was being used to clear some buildings of fumes. Simply, a hole is drilled through the concrete floor of the basement of a building, a pipe is inserted down the hole into the ground, and then a vacuum/blower extracts the vapor and vents it into the atmosphere.
Hess said that nine such systems had been requested, and that Wasatch Environmental, the company hired by Top Stop to perform the remediation work under the direction of the state Department of Environmental Quality, had concurred with all nine requests.
Until now, focus on toxic chemicals has centered on benzene, a known carcinogen. Council member Lori Nay, however, asked, “Are there other chemicals that we need to be aware of?”
Hess said he had also started to look for naphthalene, which occurs naturally in gasoline.
Brad Johnson, director of the DEQ’s Division of Environmental Response and Remediation who also attended the meeting, said that focusing on the most serious contaminant, in this case benzene, is standard.
“Even though we test for those other chemicals, we have found that if we take care of the exposures from the most serious chemical, it takes care of the rest as well,” he said. “We are aware that there are others out there that we need to be looking at.”
Johnson answered another of Nay’s concerns, which she expressed when saying, “I think it’s time for some new legislation. I have some people that are very interested in some new legislation.”
Johnson indicated that he and others at DEQ had already scheduled a meeting to discuss policies and regulations called into question by the incident.
“I don’t know [if] legislation is necessary, but perhaps some rule changes,” he said.