CHESHIRE — Officials with the state Department of Energy and Environmental Protection are weighing whether to fine the town after missteps during a pipe rehabilitation project carried out last summer left some 150 fish dead and floating in gray, cloudy water along Cuff Brook.

Contractors hired and overseen by the town engineering department had been spraying a concrete fiberglass mixture to reline an aging culvert that carries the brook’s waters under Marion Road last July when the incident occurred.

The town and National Water Main Cleaning Co., the contractor hired to complete the work, both received notices of violation from the state Department of Energy and Environmental Protection for failing to prevent the uncured geospray concrete and fiberglass mixture from mixing into the brook, which the DEEP says altered the water’s pH levels and killed the fish.

The 150 dead fish, DEEP officials noted, might be an undercount. Town officials received the written notice from DEEP on Oct. 17.

DEEP officials were on scene inspecting the site on July 18, four days into the project, after a Marion Road resident reported seeing discolored water and dead fish floating in the brook.

According to the DEEP, the resident reported that an unknown substance appeared to have been discharged into the water. In addition to the dead fish, the resident also reported an oil sheen “and a strong chemical odor similar to lighter fluid coming from the stream.”

The fish killed were mostly small species — smaller than four inches — including brook trout, American eel, redfin pickerel and blacknose dace.

“Given the nature of the violations discovered during the inspection, this

department is proposing to enter into a formal enforcement action that will include assessment of a civil penalty,” wrote Oswald Inglese Jr., director of the Water Permitting and Enforcement Division, in the Oct. 17 notice. The division falls under the umbrella of DEEP's Bureau of Materials Management and Compliance Assurance.

The work was being carried out between July 15 and July 19.

Town officials solicited bids from contractors to rehabilitate the 54-foot-long pipe to restore its “hydraulic and structural integrity” last winter.

The bid request stated the project was to be completed over the summer when waterflow was expected to be low and “manageable by cofferdams, dewatering systems and bypass pipes.” The contractor would be responsible for making sure the work was successfully completed “under dry conditions.”

The successful bidder was to submit a plan that provided “specific details of the proposed water handling plan.”

DEEP investigators found that the mortar, containing fiberglass and concrete, that was sprayed to line the culvert was released into the stream, covering the bottom over a distance of about 100 yards downstream from where contractors had been working.

The fish kill extended from the work area to the Currier Woods road crossing, less than a quarter mile away.

Investigators found initial reports blamed the incident on the failure of a pump that was supposed to bypass the stream around the work area. “These reports claimed the release occurred when the pump was unable to keep up with the increased stream flow caused by heavy rain at the site. Specifically, that the overflow from the bypass system ran through the work area and pushed concrete downstream,” read a DEEP memo dated Aug. 6.

The project halted immediately upon the DEEP being notified, and would not be completed until early November.

Cleanup started on July 19, the day after the DEEP had been alerted, and continued throughout that weekend. Contractors flushed deposits of the stray concrete off the bed of the stream and area, extending around 500 feet, and pumped it out using vacuum trucks.

DEEP investigators met with the National Water Main Cleaning Co. site superintendent responsible for overseeing the project, who explained that the crew working the site did not run the stream bypass system at the time they were spraying concrete into the culvert. That allowed flowing water to wash concrete from the work area into the stream.

“... The soluble portion of the concrete would have raised the pH in Cuff Brook to levels that would be toxic to aquatic life,” investigators wrote. “Insoluble concrete sediment escaped the work area because the erosion and sedimentation controls and the approved stream bypass outlined in the project approved by the Town's Inland Wetlands Commission through the permit issued on May 28 were never installed.”

National Water Main Cleaning Co. was cited for “discharging Geospray Polymer to Cuff Brook without a permit, failing to properly operate the stream bypass pumps and failing to install the erosion and sedimentation controls in the work area in accordance with the approved project plan.”

According to investigators, Public Works Director George Noewatne said on the day the fish kill occurred, National Water Main Cleaning Co. was not scheduled to work, because of thunderstorms in the weather forecast.

Meanwhile, company employees informed town engineers they planned to patch areas of the pipe where previously sprayed material had “fallen off.” They planned to work “a short while,” and would leave the site if they found water flow “rates were too high to be managed by the bypass pump.”

Fisheries biologist Bruce Williams, the investigating biologist, wrote, the fish “most probably died due to changes in pH and particulates in the water column. Concrete used for centrifuge casting culverts may also contain additional components, like fiberglass or epoxy resins, which may have increased the lethal effects.”

Williams wrote the fish kill appeared to be the result of wet, uncured concrete washing into the brook.

“The largest amount of concrete in the brook was in the first 100 yards downstream of the culvert,” he wrote, “but there were signs of concrete and turbity all the way down to Currier Woods Road, approximately 0.2 miles downstream of Marion Road. There were also dead fish in the brook all the way down to the pool on the downstream side of the Currier Woods Bridge.”

“... The number of dead fish observed directly downstream of the culvert may be an undercount due to the turbidity and the amount of concrete in the brook,” Williams added.

The town's Inland Wetlands and Watercourses Commission issued a permit for the project under the condition that the project “would “not have a significant adverse effect on adjacent wetlands or watercourses.” The commission stipulated all “erosion controls shall be properly installed prior to the commencement of activities and shall be monitored, inspected and repairs made when needed.”

Town officials were made aware National Water Main Cleaning Co. had been working without the proper erosion controls in place. Town Engineering Operations Manager Don Nolte emailed the company's supervisor that without them, there could be “wetland enforcement problems and the need for [the crew] to clean up the stream bed.”

Nolte further advised: “I don't want to have to attend a violation hearing with you if not corrected and caught.”

Noewatne and Nolte did not respond to requests for comment.

In a written statement, Cheshire Town Engineer Walter Gancarz blamed the incident on National Water Main Cleaning Co.’s “failing to ensure that the dewatering system was operating properly as outlined in our plans while working on the Cuff Brook culvert.”

Gancarz added, “The town has the responsibility to monitor the contractor’s work and didn’t do so ... We have implemented additional protocols and improved communication to prevent this from happening again.”

Dennis Sullivan, vice president for National Water Main Cleaning Co., which has offices in Canton, Massachusetts, and Rocky Hill, acknowledged his company was at fault in the incident. Sullivan said the supervisor who had been overseeing the project has since been fired.

Town records show National Water Main Cleaning Co. was awarded an $89,500 contract last March to complete the project. Other communications and records show that dates for when the work would be completed had been pushed back over town officials’ concerns about the impact of rainfall on the project.

Sullivan said National Water Main Cleaning Co. has cleaned up the brook and remediated the culvert at no further cost to the town.

Sullivan said the company also has offered to restock the brook with new fish, an offer on which he said officials have not acted.

mgagne@record-journal.com

203-317-2231

Twitter:@MikeGagneRJ