Deadly gas leaking from old, underground coal mines in Rock Springs forced the evacuation of several Ash Street homeowners for a few days' stay in a local motel, residents said Tuesday.

The gas seepage into her home was so strong that it caused Kelley to seek medical attention, she said. Her doctor told her she was experiencing symptoms of exposure to hydrogen sulfide gas, or H2S.

"It's been horrible, just a nightmare ... This is one of the things we feared the most would happen," Kelley said in an interview Tuesday afternoon while waiting for state officials and consulting engineers to arrive at her home.

"They moved stuff around down there with this (subsidence) project, and now we've got black gas coming up from the ground ... They've opened up a volcano down there, and it's getting worse and worse," she said.

"The H2S gas is literally seeping through the floor of my house, and it's making me physically sick to my stomach every time I go back in," said Kelley, who has been living in a local motel since leaving her home Thursday.

Hydrogen sulfide gas is normally heavier than air, but when agitated, it can erupt from underground coal mine voids in levels of toxicity that can paralyze the lungs. Low-level exposure to the gas can cause sore throats, respiratory infections and other medical ailments.

Wyoming's new Abandoned Mine Lands director, Todd Parfitt, could not be reached for comment Tuesday. Office personnel said former director Evan Green, who oversaw the ground-pounding project, took early retirement last month and is no longer with the agency.

Kelley said a consulting engineer from Colorado placed gas monitors in her home's bedroom, front room and under the house on Thursday. On Tuesday, engineers were back to place five additional, "more sensitive" gas monitors in her house.

Kelley and several area homeowners believe the gas seepage was caused by the now-defunct mine subsidence project conducted on nearby vacant lands. The project aimed to free up those lands for much-needed housing development.

Residents near the work site expressed outrage at the ground-pounding project that used a new process called dynamic compaction. They contend the project severely damaged their homes and is now causing mine gas to seep into their homes, rendering them virtually worthless at this point.

"I just bought my home, and it looks like I'm going to have to move now ... But who's going to buy it now with all this?" said exasperated homeowner Dwayne Shafe.

Shafe said his family stayed in a motel Thursday and Friday nights after gas monitors placed in his home by engineers showed higher-than-safe levels of hydrogen sulfide.

"We just got our first new-homeowner loan, and now am I going to have to sell, which I can't, and move again?" he wondered. "We just don't know what we're going to do. We've been jerked around in so many different directions, we just don't know anymore."

For several weeks beginning July 17, the state's Abandoned Mine Lands division used dynamic compaction to collapse underground mine voids on a 61-acre tract of land near downtown Rock Springs. The process involved lifting large, 25-ton weights and dropping them repeatedly on undermined areas.

The land lies over what was known as the nearly century-old Excelsior/John Park coal mine that was leased by the Union Pacific Coal Mine in 1911.

A housing shortage in Rock Springs, spurred in large part by a natural gas boom in southwest Wyoming, prompted city officials to take another look at undeveloped lands within city limits that had not been scrutinized before because of mine subsidence possibilities.

Sink into the void

At the request of city officials, the state began the $2.4 million pilot dynamic compaction project in July with an eye toward making about 840 acres available for affordable housing with about 190 acres of mine void mitigation work.

AML engineers said the weights were dropped more than 2,700 times before work was halted Aug. 6 after residents complained to city officials about vibrations and noise from the project.

Residents said cracks were appearing in some homes' walls, ceilings, driveways and foundations as a result of the ground pounding. Kelley said her house alone suffered more than 80 cracks and other kinds of damage since the project began.

State officials met with residents in a packed, sometimes contentious town hall meeting Aug. 14 to hear their concerns. After getting an earful from residents, the agency shut down the project for good the next day.

Doug McIntosh -- who organized a homeowners group to fight the project for his ailing, elderly mother who lives on Ash Street -- said he is worried that the recent shakeup at the top level of the AML program may jeopardize a "handshake" agreement with agency officials last month in which the state pledged to pay for any damage resulting from the project.

During the Aug. 14 town meeting in Rock Springs, John Corra, director of the Wyoming Department of Environmental Quality, which oversees the AML division, said repairs to all houses suffering from damage from mine subsidence -- whether caused by the dynamic compaction or not -- would be paid by the state through the AML division's insurance program.

McIntosh said residents were upset that they weren't informed about Green's departure.

"Our homeowners' agreement was with (former director) Green, who we thought was acting as a liaison between us and the state," McIntosh said Tuesday afternoon.

"We had a gentleman's agreement on his handshake," he said. "Now he's gone, and we've haven't heard any kind of progress report or anything from anybody at the AML. A lot of people are upset."

Kelley said she is unsure now if she'll ever get back into her home.

"Before this is all over, I fear we're going to get sunk ... and I mean literally have my house sink down into the void," Kelley added. "My biggest fear is I'm going to go up there one day and everything is going to be in a big hole in the ground. It's just awful what they've done to my home. With a gas leak, you just don't know what can happen next."

Southwest Wyoming bureau reporter Jeff Gearino can be reached at 307-875-5359 or at gearino@tribcsp.com.