A wastewater treatment plant serving Glen Ellyn and Lombard will lift a seven-month ban on deliveries of outside food waste used for a system that creates biogas and caused a foul odor last summer.
An occasional smell is not uncommon with the Glenbard Wastewater Authority facility, but the summer stench lasted for weeks and drew dozens of complaints from neighbors who were forced indoors when the putrid odor became particularly offensive.
The culprit stemmed from a disruption in two digesters at the plant that treats sewage and wastewater for from more than 109,000 homes and businesses in and near Glen Ellyn and Lombard.
The authority last year implemented a new system that relies on biogas, a renewable energy source, to provide heat and electricity to the plant. The facility accepted fats, oils and grease from outside haulers to boost the production of biogas.
But during the first week of August, the authority received a higher-than-normal amount of grease from haulers, and operators ended up putting too much material into the system, upsetting the digesters.
The authority halted deliveries of grease until an executive oversight committee made up of Glen Ellyn and Lombard officials set new protocols.
"We have been working on this over the period of the time of the moratorium and worked with our consultants, asked for input from the community as well and developed a standard operating procedure to better regulate this entire process," Glen Ellyn Village Manager Mark Franz said Thursday.
That procedure stresses better monitoring of deliveries to the plant at 21W551 Bemis Road, Franz said. Though there were guidelines in place before, operators have now laid out a schedule tracking receipt of the materials and how much of the grease they're transferring to the digesters.
The plant also will only accept up to a certain volume of the fats, oils and grease per day, ideally from one hauler that can meet that threshold. The goal is to resume deliveries April 1, after re-recruiting a hauler and completing a permitting process, said Matt Streicher, who was appointed as executive director of the authority beginning in January.
"Probably the most significant change is that we've installed an additional pump which will allow us to have greater control of what we feed to the digester," Streicher said. Computer programming also will help manage the pump "so it's not just left up to operator control."
The authority expects to reduce energy costs by about 30 percent or anywhere from $100,000 to $200,000 in the first year the system is back online, Streicher said. In the long-term, those savings could grow to an estimated $400,000 to $500,000 annually. The environmentally-friendly system could eventually provide enough electricity to power the entire plant.
The authority also could receive roughly $200,000 in revenue from fees charged to haulers on a per gallon basis.
"For the first 12 months, we're approaching it very conservatively in order to demonstrate that we can do it very successfully," Streicher said.
Franz said officials are "very confident" that the changes will prevent another disruption to the system and the lingering odor that permeated the unincorporated neighborhood. But he cautioned that the operation will produce odors from time to time because of the nature of the biological process.