Aldermen approved a contract with CM Archer Group PC, St. Louis, for design and bidding construction administration services for sludge removal in the city’s waste water treatment facility on Denton Road.

Cost of the engineering for basic services is not to exceed $23,330.

Under the agreement, CM Archer will prepare contract documents for the sludge removal process, oversee bidding of the work and provide administration of the actual construction.

If the city desires the firm to observe construction, there would be an additional $5,000 charge.

Sludge removal at the lagoon has been discussed in a series of meetings involving the city sewer system and was recommended in the Wastewater Master Plan finalized earlier this year.

The intent under this agreement is to remove sludge at Cell 2, in advance of the aeration equipment repairs and upgrades currently in design.

Sludge removal was discussed during budget preparation, but was not included in the final budget, according to City Administrator Steve Roth.

Robert Brueggemann, public works commissioner, estimated the cost to remove sludge from Cell 2 would be $400,000.

The city had initially talked with Burns-McDonnell Engineering about consultation services for the sludge removal. But that firm, which was awarded a contract for engineering for the $1.3 million flood damage repair project, suggested that the city contract separately for the sludge removal planning.

CM Archer was the second-ranked firm in the wastewater treatment facility engineering selection process.

Roth said the city does not have funding to remove sludge from all lagoon cells, but does have available funds for the Cell 2 removal, which would help complete the aeration upgrades contemplated for later in the year.