MARENGO – City officials still are developing a plan to salvage their $12 million upgrade to the aging wastewater treatment plant, while they brace for a one-year construction delay and looming project changes.
Officials from Marengo and the Illinois Environmental Protection Agency confirmed that the long-awaited plant upgrade will be downsized or relocated to an area that has better soil than the project’s current location, northeast of the existing plant along Route 23, near the Kishwaukee River.
Marengo halted the project Sept. 5, after learning from the construction firm, J.J. Henderson, that an old landfill underneath the expansion site contained solid waste that would complicate construction and significantly add costs to the $12 million project.
H.R. Green, the city’s engineering firm, confirmed last week through various test results that the expansion site had a high metallic count and unknown volumes of solid waste, including refrigerators and washing machines, buried underneath it.
“Do we anticipate building on this landfill area? Absolutely not,” City Manager Gary Boden said. “It’s just not cost-productive.”
The old, capped landfill sets back a project that already has encountered numerous delays. In 2011, the city received construction bids that would have cost the city between $15 million and $19 million, exceeding Marengo’s budget for the project.
Bidders claimed then that the high bids were related to the plant’s proximity to the Kishwaukee River and raised questions about the durability of the soil, along with other environmental and safety issues.
The project’s designer, McMahon and Associates, then stripped the project, and the city had to rebid the project. The council in April finally selected Gurnee-based J.J. Henderson to build the $12 million project.
But the bidders, city staff, aldermen and the McMahon group never publicly questioned the old landfill, a review of city minutes shows.
Boden said the city was aware of it, especially since the IEPA in the mid-1970s ordered Marengo to close and cap the unregulated garbage dump.
But the city proceeded with McMahon’s design to build on top of the landfill because staff relied on the project engineer’s expertise, Boden said.
Last fall, McMahon conducted a soil test to ensure the site was safe for construction, Boden said. The results revealed that the old landfill contained only construction debris and was an affordable problem to overcome, he said.
It wasn’t until almost a year later when J.J. Henderson crews found solid waste in the landfill after starting to excavate the site. The holes since have been refilled.
Officials now are trying to figure out whether McMahon’s design can work elsewhere or determine whether another stripped-down redesign still provides enough pumping capacity to meet the city’s future needs.
The city also will need to assess its relationship with McMahon. Boden would not comment on the matter, and representatives from McMahon did not respond to calls for comment.
“We relied upon their expertise,” Boden said. “We hired them as engineers who have expertise in building sewage treatment plants. No city carries that kind of expertise. That’s why you hire engineering firms to do what they do.”
The city hired McMahon for $1.1 million to do design and project inspection work. The city so far has paid $400,000 in design costs to McMahon.
The city also will have to decide on terminating its contract with J.J. Henderson, as the project will be delayed for at least a year. The city currently owes the Gurnee firm $158,000 for on-site work.
With the project delayed, city staff has suspended the wastewater rate increases that went into effect to finance the $12 million project. The city in 2011 doubled rates from $3.44 per 1,000 gallons to $6.44 for residents and commercial users.
City administration is proposing cutting the increased rates by 50 percent for 18 months. The temporary reduction could last longer if the project is delayed for more than a year, Boden said.
The rate increase has generated $760,000 this year, which mostly has gone to paying McMahon and J.J. Henderson. The 50 percent reduction would knock that revenue total to $380,000 a year.
The council will provide direction on the modified water rates during its regular meeting at 7 p.m. Monday in City Hall. The council also will meet in a closed session to discuss potential legal action concerning Marengo’s latest setback to its plant upgrade.