The Board of Mayor and Aldermen Monday hired a Jackson-based consultant to determine the cause of a problem that made one of the two clarifiers at the city’s wastewater treatment plant on Rifle Range Road pop out of the ground.

CDM Smith of Jackson, which specializes in environmental projects, was hired by the board at a cost of $28,000 to examine the problem and recommend a solution. The board also approved a resolution declaring an emergency to repair the clarifier once the problem is determined.

The clarifier was forced out of the ground Feb. 12 by water from an unknown source that pushed the 20-foot deep, 100-foot diameter pool from its pilings and burst several pipes under it, including a 30-inch water line. The clarifier is used in the wastewater treatment process.

The board Feb. 25 authorized contractor J S Haren, which is upgrading the clarifier, to plug a ruptured 30-inch water line and repair other lines broken when the clarifier popped out the ground at a cost of $31,990. The repair is supposed to remove water from the site so engineers can examine it.

“What we want is for the contractor to try to stop sewer from flowing out and fix the sludge line so we can go back to normal operation,” Public Works Director Garnet Van Norman said. “Once that’s done, then CDM Smith can come in and take a look at the situation we have, and advise the city on the best path to follow. What that is at this point, I don’t know.”