A 1.8 million gallon leak of partially treated sludge at the John E. Egan Water Reclamation Plant near Schaumburg occurred June 19, not June 5 as officials originally reported this week.
Bruce Yurdin, manager of the field offices of the Illinois Environmental Protection Agency's Bureau of Water, said the date of the major leak was confused with that of an unrelated and less significant event involving the discharge of primary effluent from a vent pipe at the same facility.
In both cases, officials from the Metropolitan Water Reclamation District of Greater Chicago properly responded and notified the IEPA within 24 hours as required, Yurdin said.
The sludge that leaked from the facility, 550 S. Meacham Road, came from a break in the pipe that transports the material from the James C. Kirie Water Reclamation Plant at 701 W. Oakton St. in Des Plaines, said Allison Fore, public affairs specialist for the water reclamation district.
Sludge is a nonhazardous waste material that is a byproduct of the treatment process that occurs at the plants, she said. The pipe that broke carries only sludge that has been through secondary treatment and is more than 99 percent water.
The staff at the Egan plant discovered a hole in the pipe located in a fenced-in area on the district's property and immediately stopped pumping to allow for repairs, Fore said. The IEPA was immediately notified and sent officials to monitor the repair and cleanup work, she said.
The water reclamation district conducted a bacteriological investigation at six locations along the nearby Salt Creek and Busse Woods Lake and found no effect on the water quality, Fore said.
Most of the leaked sludge ended up in a quarry on the district's property, she said. A smaller amount went into a section of Salt Creek also on the district's property.
All recoverable sludge from the bed of the creek and adjacent area was removed by the water reclamation district for proper disposal, Fore said. The broken pipe has since been repaired, tested and put back into service.
Yurdin said a leak of this magnitude requires the IEPA to maintain oversight of the environmental impact for an indefinite period likely to last for several weeks or months.
The chief concern is the impact on aquatic life, though there has been no evidence of a fish kill from the leak, he said.