A new screening system/grinder is now in place at the Eastern Reception Diagnostic Correctional Center (ERDCC) in Bonne Terre. The system has been discussed several times in the past due to the issues the city was having with the original screen which wasn’t designed to accept plastics.
Alex Dunker with MECO Engineering Company, Inc. discussed the project with the city council recently. He said they are done with the grinder project.
“I don’t think there are any other loose ends, but if something comes up we will get with Alliance,” said Dunker. “We aren’t running away when we are done. If something comes up we will be sure it gets fixed.”
Dunker presented the council with a letter describing the work they did with the project and also discussed the contract with the correctional center. Due to what is in the contract between the city and the correctional center, the city should have never had to install a grinder, he indicated.
The correctional center is not supposed to send trash through the wastewater and should have equipment set up on their end to filter it out. Alliance has repeatedly found items in the wastewater including jumpsuits, Ramen noodle plastic wrappers, and various materials.
“It associates a dollar amount with that and when you guys ask them for money, if you ask them for money for reimbursement ..." Dunker said. “I can’t get into the legal end of things ... that is where the attorney will come in ...but what I can do is provide a letter on my end.”
Dunker said the letter would represent his opinion and describe the circumstances. He added according to the contract it shouldn’t have been necessary.
“That is what that letter entails,” said Dunker. “From what I understand, approximately 92 percent of the wastewater comes from the prison to that treatment plant ..."
MECO Engineering entered into a contract with the city of Bonne Terre in September 2016 and the services included design and construction observation/inspection for new screening equipment.
“The Northeast Wastewater Treatment Plant (WWTP) treats 100 percent of the wastewater coming from the nearby correctional facility and a small amount of residential wastewater from homes in the area,” Dunker reported. “It is estimated by operators that the daily flow of the plant consists of approximately 90 percent prison flow and 10 percent residential flow.”
Dunker said a majority of the flow and trash is coming from the prison. He added initially they were presented with a contract between the city and the Missouri Department of Corrections, which clearly outlined the wastewater quality sent to the plant from the prison.
“In other words, there is a contractual agreement in which composition of the wastewater, including soils or trach, that the city is obligated to treat is specifically outlined,” Dunker said. “In the design of new screening equipment for the facility, the volume and type of trash to be removed was considered for proper design.”
Dunker said during multiple site visits and discussions with operators in city personnel, MECO Engineering Company saw that wastewater quality standards outlined in the contract were not being adhered by the prison.
“On two separate occasions, MECO personnel saw trash passing through and around the prison’s channel grinder and going downstream where it was eventually collected by the city’s primary bar screen,” Dunker said. “A routine inspection by the Missouri Department of Natural Resources (DNR) also noted similar deficiencies and an abundance of trash which could be reasonably assumed to have come from the prison.”
Dunker said due to the overwhelming amount of trash in the system, the city has been unable to properly treat wastewater according to DNR standards and has been notified to fix the deficiencies.
“History and preliminary conversations with the state of Missouri personnel led us to believe that the prison does not intend to fund any treatment equipment to help adhere to the contractual wastewater effluent requirements,” said Dunker. “These initial conversations with the state to help fund improvements were not effective.”
MECO Engineering was required to design improvements under the worst-case scenario in which the city will continue to receive untreated, high solids wastewater from the prison.
Dunker said their final decision included a heavy duty, in-channel grinder, which is specifically designed for the worst solid loadings, such as prisons, as well as a fine screen auger to remove the shredded trash from the waste stream.
“It is our opinion that if the prison was delivering contractual-quality effluent to the Northeast WWTP, which specifies a half inch or less solids, with no plastics, the grinder portion of our design would not be needed,” Dunker said. “If the WWTP was receiving a half inch or less solids and no plastics, on a reliable basis, the only equipment needed would be a fine screen.”
Dunker explained there are many variations of fine screens that would have been acceptable if the prison was in compliance. If they would have only installed fine screen with the current trash coming through it would have failed in a very short period of time.
“The city and MECO Engineering had to design improvements in an effort to maintain compliance with DNR wastewater standards,” said Dunker. “The grinder, which shouldn’t have been needed, costs $40,000 from the manufacturer.”
He explained that contractor markup is typically 15 percent of the equipment cost and proper installation and labor by a qualified contractor is usually 80 to 100 percent of the cost of the equipment.
“It is my estimation that approximately $82,000 to $92,000 of this project should not have been needed if the incoming wastewater was of contractual quality,” Dunker said. “In addition, the city will now have to maintain this piece of equipment at costs which will be realized once the equipment is in use.”