Updated 7/3/14 with a link to the state's finalized Incident Management Plan for the Bridgeton Landfill.
State agency officials are concerned that the underground fire at the Bridgeton Landfill could break through to the surface.
That scenario was raised in a recent memo by landfill fire expert Todd Thalhamer, who has been consulting for the Missouri Department of Natural Resources.
In his memo to MDNR, Thalhamer said some of the highest underground temperatures so far had been recorded at the landfill in May and early June.
Thalhamer was particularly concerned about measurements at one temperature monitor, where readings above 200ºF were recorded just nine feet below the landfill’s surface.
That monitor, TMP-13, is located in the narrow neck of the landfill, between the north and south quarries. If you zoom in on the diagram below, it’s visible right in the center of the neck. This map is part of the first figure in this infrastructure report.
The monitor TMP-13 is in the middle of a line of gas interceptor wells; the closest one is labeled GIW-9.
Those wells are supposed to keep the underground fire in the south quarry from spreading to the north, in the direction of radioactive waste at the adjacent West Lake Landfill.
Thalhamer said based on the latest temperature readings, “one might conclude the subsurface fire/smoldering event is past the last line of gas interceptor wells.” But, he said, he would need to see the next round of carbon monoxide data to know for sure.
In a written statement, Republic Services spokesperson Russ Knocke said “with respect to the notion of daylighting, we do not consider it to be a risk.” He said MDNR’s consultant Todd Thalhamer was “either misinformed or irresponsibly sensationalizing limited data.”
About the temperature monitor that Thalhamer said showed high, near-surface readings ― the thing he was most concerned about ― Knocke said: “Mr. Thalhamer ;is aware that TMP-13 is currently inoperable.”
The last set of carbon monoxide data for the landfill, issued for May, suggested the underground fire had not moved farther north into the neck. Landfill owner Republic Services is required to test for carbon monoxide in the neck area of the landfill every month, according to the company’s latest agreement with Mo. Attorney General Chris Koster. That means June’s readings should be available in a couple of weeks.
Chris Nagel, who directs MDNR’s Solid Waste Management Program, sent Thalhamer’s memo to Republic Services, along with a letter expressing the agency’s concerns.
In it, Nagel wrote that the subsurface fire had now spread to encompass “the majority” of the south quarry, and that “the southern portion of the neck” was also experiencing elevated temperatures.
Nagel said that his staff has been working with first responders and staff from the landfill to draft an “Incident Management Plan” for the Bridgeton Landfill, which has now been finalized.
It lists the steps that landfill staff will take in the event of a surface fire (see p.9), including calling the Pattonville and Robertson fire departments, and notifying MDNR.
In his letter to Republic Services, Nagel said first responders will be preparing “Incident Action Plans” in preparation for an “Incident Management Strategies Meeting” this month. He said fire district command staff will also visit the landfill to familiarize themselves with the facility.
In addition to developing a plan of action, Nagel said the following steps had been taken to prepare for a potential surface fire:
- Purchase of firefight foam;
- Outfitting of an ATV as an “all-terrain ambulance;”
- Purchase of a “storz connection” to allow the facility’s water truck to connect to the fire district’s pumpers;
- Development of a web portal to provide Material Safety Data Sheets and updates to the response plan, “such as quarterly maps of landfill infrastructure;”
- Identification of soil stockpiles on the maps (presumably for use in smothering a potential fire); and
- Marking of roadways.
Still, the Missouri Coalition for the Environment’s Ed Smith is worried about what could happen if the underground fire breaks through the surface, producing flames and smoke.
"Because there's a host of unknown materials in the south quarry,” Smith said. “You could have the release of different types of [toxic substances]. This isn't just a typical brush fire you're talking about."
Follow Véronique LaCapra on Twitter: @KWMUScience