The old margarine commercial warned against fooling Mother Nature. If you’re in industrial painting, you might not want to gamble with her, either.
That’s the lesson that town officials in Ithaca, NY, have learned since being saddled all winter with a slow-curing water storage tank paint that has been releasing VOCs from m-xylene, o-xylene and ethylbenzene into the town water supply.
After months of testing showing the chemicals above New York State’s Maximum Contaminant Level (MCL) of 5 ppb, the town’s latest tests, conducted March 31, showed all but one sample below the limit. The other sample tested at 11 ppb, but had declined from 14 ppb, officials said.
The town has completely drained the 500,000-gallon tank once, partially drained it once, and has been overflowing it for two weeks to flush out the contaminants. At this point, officials expect that the warmer weather will allow the curing process to finish and resolve the VOC release. No recoating is expected.
‘Pushing the Envelope’
“It was more an issue of timing,” town public works director Jim Weber said Thursday (April 7) in an interview. “If we had had two or three days—or maybe three or four days—we wouldn’t be in this situation.”
Officials knew the timing on the project would be tight. Budget deliberations held up approval on the project until July, when most tank painting in the area is completed. That meant advertising the job in August and pushing the work into the fall.
Still, Weber said, the project could not be put off: The town’s staff was already overwhelmed by a full list of 2011 projects, and the repainting job was considered critical.
“We knew we were going to be pushing the envelope on the warm weather to get this done,” said Weber. “We knew as part of this that the curing of the paint was critical and that it had to be done during the warmer weather.”
But he added: “We thought we still had a window to complete the project and get it done.”
The project drew three formal bids. In addition, several companies phoned to discuss the project but declined to bid when they learned how late the project would run, Weber said.
Officials at the Bolton Point Municipal Water System, which includes Ithaca and four other municipalities, say they advised against the project.
Ithaca Public Works Department
|Painting on the Ridgecrest Road water storage tank was completed Nov. 15.|
Bolton Point general manager Paul Tunison said in an interview Thursday that the commission had had a brief curing problem with one of its own tanks painted in September 2007. Then, too, the MCL levels exceeded the state limit. A week’s warm-up resolved the issue.
However, the experience taught the commission a lesson, he said: “Don’t paint it in October, because it’s too cold.”
Tunison said the commission “expressed concern” about the Ithaca project during the bidding period, “but we don’t have any control over their project schedule.”
Township officials, who had budgeted $150,000 for the project, accepted the $115,800 low bid of JNP Construction Corp., of South Hackensack, NJ. No third-party coating inspector was used or considered, Weber said.
The project involved removing the old wax coating and replacing it with Sherwin-Williams Macropoxy 646 PW, which Sherwin-Williams describes as a “high-solids, high-build, fast-drying, polyamide epoxy classified by UL to ANSI/NSF 61 as a tank lining for potable water storage tanks.”
Two coats of 4-5 mils each were applied.
Weber said he would have preferred another wax coating, but the Health Department opposed it, saying the wax occasionally plugged customers’ pipes and looked bad when it leaked into the water.
‘They May Not Have Had Enough Staff’
The work began “within a reasonable time frame once the notice to proceed was issued,” said Weber. Although progress was steady and met the terms of the contract, the crew was limited.
“When they were sandblasting the wax off the interior, would we have liked to see more than one or two people there? Yes,” said Weber. “They had one person in sandblasting where they could have had two.”
He added: “We tried to work with the contractor. But you can’t tell them they’re doing it wrong if they’re working within the parameters of the contract.”
He added: “The product was good and it was sound … They may not have had enough staff on it all the time.”
The project was completed Nov. 15, just a couple days after a long stretch of beautiful weather abruptly nosedived into 24-hour freezing temperatures, Weber said.
The coating requires ambient temperatures above 40 degrees Fahrenheit to cure—and, when the cold hit, said Weber, “it just shut the process down.”
Blowers and, later, heaters were brought in to help speed drying and curing. JNP had to pay about $1,600 to rent the equipment. When the water was sampled and found to be within acceptable limits, the contractor’s role ended.
However, subsequent sampling showed results above the MCL, so the town took the lead from there.
‘We Have Plenty of Experience’
Jery Pariaros, of JNP, said Thursday that the cold snap came after the painting was done and that it had been warm enough for the paint to cure throughout the job. “This company started in 1983,” he said. “We have plenty of experience.”
Pariaros said his company has painted many water tanks in the Northeast in the fall and early winter without curing issues. He said he did not know about Ithaca’s curing problem.
Ithaca has not drained the tank again, saying it needs the water for fires and other emergencies.
Officials also note that the federal Environmental Protection Agency sets a maximum level of 700 ppb for ethylbenzene and 10,000 ppb for xylene.
“We are following all the appropriate rules and regulations of the state and of the industry,” said Weber.
And while the issue should be resolved soon, he said, the experience has left a lesson and a reminder:
“We pushed our luck just a little bit. And Mother Nature still holds the purse strings and calls the shots.”