Geologist proposes solution for sinkhole prob.

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Daily photo by John Godbey
A motorist navigates a depression caused by a sinkhole on Old Alabama 24 near West Morgan Elementary School.

Geologist proposes solution for Trinity sinkhole problem

By Ronnie Thomas
[e-mail]· 340-2438

TRINITY — The sinkhole problem on Old Alabama 24 began Sept. 27 when Troy Terry called police after watching a portion of the road dip under the weight of a passing school bus.

Terry lives about 200 feet from the sinkhole.

Trinity Mayor Vaughn Goodwin estimated the sinkhole at the time to be 20 feet deep with a 10-foot radius.

"It slanted under the highway," he said. "We could have buried a school bus in there."

From that moment until now, the sinkhole has been a nuisance as town and Morgan County officials play a cat and mouse game with the cavity through a series of closings, rerouting traffic, filling, patching — and reopening.

The town consistently purchases cold mix for the area to build it back up as the sinking continues. Officials are looking for a permanent fix.

On Monday, the state Department of Transportation's chief geologist, Willard L. Sitz, met at the scene with Goodwin and Town Engineer Sonny Wright.

"He suggested that we take a drill rig and see how far we can drill down and hit solid ground," Goodwin said.

"He said that if we're close (to hitting solid ground), we should continue filling (the sinkhole) and that it will eventually settle."

Goodwin said Sitz told them if they did not get close to solid ground, they should dig beside the road and pump in concrete to form a solid plug.

"He said that now, all the rocks that we've used to fill in the hole are lying in there loose, and could be dropping one at a time, causing the road to sink," Goodwin said. "He said that the concrete ties all that stuff together and that it will hopefully take hold along the edges down in the hole, basically sealing it."

Goodwin said that on Nov. 1 during yet another time the sinkhole caved in and caused Trinity to close a portion of the road, crews dug down about 45 feet and dumped more than 200 tons of rock.

"At that point, we did not hit solid ground," he said.

Sitz told Goodwin that state officials have used the plugging method for most of the sinkhole problems they've encountered.

"He also said he won't guarantee that it will work, but it's something we can try. At this point, I'm all for it," Goodwin said. "After having seen the site, he told us he would check with his people and that if others have suggestions, he'd pass them along, too."

Goodwin said Wright will check pricing for the work. The mayor said he anticipates getting construction under way within a couple of weeks.

"And, yes," Goodwin said, "it will mean closing the road again, but this time, we don't expect it to be for long."

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