More work on the heating, ventilation and air conditioning unit at The Centre's indoor swimming pool was authorized by the Rolla City Council Monday night.

"With the original RFP and additional tasks the total contract is $466,842," Parks and Recreation Director Scott Caron explained in the written agenda commentary.

The council on Nov. 5 approved selecting Jarrell Mechanical Contractors of Earth City "for contract negotiations to construct natatorium mechanical upgrades."

Jarrell's response to the request for proposal was $400,442 for replacement of the pool HVAC. Since then, Jarrell has identified other areas that need attention, and Caron outlined four areas he recommended adding to the original work:

Air balancing the entire air distribution system for $30,500.

Cleaning of the duct bank for $19,800.

Increasing temperature, humidity and chloramines monitoring for $8,350.

Replacing two six-inch manual shut-off values with electric-operated valves for $7,750.

Jarrell also recommended, but Caron did not go along with, the following:

Encapsulating the duct bank with a sealing material on the concrete surfaces for $14,500. Caron said debris in the ductwork appeared to be from construction, and "with additional awareness and maintenance excessive issues will not occur in the future."

Installing an exterior sump pit for $2,500. "The existing duct bank is currently dry," Caron said. "This project can be completed later by staff if deemed necessary.

Replacement of the water pump on the supply line of the leisure pool for $4,850. "Our staff has replaced the seal on the pump," Caron said.

Caron said the work will be done in late March to early April.

"The pool will not be accessible during the construction, which is expected to take less than seven days to complete," Caron said.

This project was estimated to cost $600,000, and Caron told the council he had expected it might reach $750,000 based on work done at other municipal pools.

The $466,842 will be paid out of the recreation center depreciation account, the reserve account left over after payment of the bonds that raised the money to construct The Centre and SplashZone. That account will continue to grow as the city collects the half-cent sales tax through the end of 2013.

There were no negative votes voiced on the motion to approve the contract. Councilwoman Fran Mazanec was present Monday night. She was mistakenly tagged as absent at the last council meeting by this reporter, who again apologizes to her and her husband, Richard, who pointed out the error in an e-mail.

Also present were Councilmen William Lindgren, Monty Jordan, Greg Sawyer, Steven Leonard, Gary Hicks, Don Morris and Tony Bahr and Councilwoman Carrolyn Bolin.

Absent were Councilmen Lou Magdits, Kelly Long and J.D. Williams.

In other business at the meeting:

The council approved participating in a cooperative buying agreement with Independence for sanitary sewer line reconstruction.

An ordinance to work with the Missouri Highways and Transportation Commission on lane additions and traffic light replacement at Highway V and Interstate 44 was approved.

Task Order No. 6 for HDR Engineering was approved. This is for improvements at the Southeast Wastewater Treatment Plant.

The council approved a motion in support of working with the Phelps County Commission and the Phelps County Emergency Services Board on a pictometry imaging project. This is an enhanced aerial photo program.

Purchase of crack filling material from Sasco Pavement Coating Inc. was approved. A full truckload will be purchased to receive the lower price per pound; the surplus will be stored.

The council heard a semi-annual progress report from the Frisco Line Neighborhood Association, presented by Rhonda Myers.