Maximum overdrive?

By Rob Marino
Friday, October 24, 2003

As concerns continue to be raised about the capacity of Newburyport's wastewater treatment plant, the city's sewer super insists the plant is well within its limits


Is the Newburyport wastewater treatment plant up to snuff?

Perhaps Newburyport Sewer Commissioner George Succi said it best recently when he went before the Salisbury Board of Selectmen to discuss the plant's capacity.

"Well, it depends on who you ask," Succi said.

In fact, while some are seriously calling into question the plant's capacity, others maintain that's just another tactic by opponents of the Plum Island water and sewer project to further stall the multi-million-dollar undertaking.

Either way, neither side is giving up without a fight.

On Monday, project opponents questioning the plant's capacity made their concerns known to the Salisbury selectmen, courtesy of Newburyport resident Jeff Robertson, who was able to get the topic placed on the board's agenda. Robertson spearheaded efforts in Newburyport this past summer circulating a petition to place a question on the November ballot as to whether a lot-by lot analysis should be conducted on Plum Island.

Robertson, who believes the plant is already at capacity, handed out a large packet to the selectmen Monday, which included letters and comments from members of the Islands Futures Group, the main project opponent.

Along with other members of the Newburyport Sewer Commission, Brendan O'Regan, the city's sewer superintendent, attended the discussion and fielded questions from the Salisbury selectmen (see related story).

Agreeing with O'Regan, Succi maintained the plant consistently meets permit requirements.

"Some people have suggested this plant has operated poorly. I'm not here to suggest that," Succi said. "There are occasional violations that have occurred, but on the whole, the requirements are met consistently on a month-by-month basis."

However, it's the flow coming into the plant and its capacity where O'Regan and Succi differ. In documentation to Salisbury selectmen, Island Futures Group members maintain "the plant exceeded 80 percent of its designed flow for over 90 consecutive days in early spring 2001 and then exceeded or reached its flow design limit of 3.4 million-gallons-per-day for three consecutive months during which time it also exceeded the plant's maximum hourly hydraulic capacity with a daily average flow of 9.6 million-gallons-per-day."

In a recent letter to the Current, Robertson cited a more specific example based on data obtained through the Environmental Protection Agency (EPA). Robertson said, "the treatment plant's average flow peaked at 4.2 million gallons a day on March 30, 2001, which is 800,000 gallons a day higher than the maximum permissible flow under EPA regulations."

In and out

While O'Regan admitted the EPA data confirms Robertson's claim, he strongly questioned the validity of the numbers, because at the time there was a significant discrepancy between the influent meter, which measures the flow entering the plant, and the effluent meter, which measures the flow leaving the plant.

Shortly after O'Regan came onboard to the department in 1996, he noticed the effluent meter was reading approximately 500,000 gallons per day higher than the influent meter.

Correcting the discrepancy was put on the five-year capital plan, and the process to fix the problem began in early 2001. Weston and Sampson Engineers, Inc. was hired to investigate the discrepancy, working with New England Instruments, Inc. to identify the problem and recommend a solution.

Weston and Sampson concluded that the influent meter was recording more accurately than the effluent meter. At the request of the sewer superintendent, the Department of Environmental Protection (DEP) in June 2001 approved using the influent meter for reporting purposes, rather than the effluent meter.

"We were using the effluent meter because we didn't know the effluent meter was faulty at the time," O'Regan said, explaining why the flows were reported to be so high in March 2001. "We proved three months after the fact that it was false and too high a number to report."

O'Regan added that significant rainfall events also attribute to higher flows and suggested such an occurrence happened in March 2001. Most treatment plants are typically built to handle significant weather events that happen once every 50 to 70 years, but not beyond that.

"When you get out of those numbers, like the 100-year event, in order to handle it, this treatment plant would have to be four times the size it is, and it would only work efficiently once every 100 years," O'Regan said.

Treatment plants, he said, are typically designed to last 20 to 30 years, "if you don't make improvements to them like we've been doing, so those unusual events where high amounts of flow occur, yeah, we're going to be outside our permit and the DEP and EPA typically realize that."

O'Regan further said that the meters are now calibrated once a year by an outside vendor. Although the meters were calibrated last spring, O'Regan said the meters were calibrated again this week. Because the spring tends to be a more hectic time of year, the superintendent said the decision was made to start conducting the annual calibrations in October.

During a recent tour of the plant (see related story), O'Regan was quick to point out the meters recording the influent and effluent don't always jive. For instance, at the time of the tour, the influent meter read 2.489 million gallons per day, while the effluent meter read 3.089 million gallons per day.

"We'll see a slight discrepancy between the two," O'Regan pointed out. "The reason for the discrepancy is because at any instantaneous time, we recycle certain flows, so you're going to have a discrepancy between the two meters. You just don't have water coming in and water leaving. You have water returning into certain areas and the two numbers won't jive all the time. But at the end of the day it equals out."

A third meter records the total flow coming through the plant, O'Regan pointed out. The difference between the flow coming through the plant at the beginning of the day and the end of the day is what's used to calculate the amount of daily flow.

The sewer superintendent said the efforts to correct the discrepancy between the meters has resulted in reporting the flows more accurately. The Island Futures Group isn't convinced, however, and has asked in its comments to state environmental agencies that both meters be replaced.

As far as O'Regan is concerned, new meters would still require an annual calibration. Replacing the existing meters would also require diverting the flow elsewhere, potentially backing up the system and causing environmental damage.

In addition to being environmentally risky, O'Regan said replacing the meters would cost hundreds of thousands of dollars, whereas annual calibrations typically cost between $1,000 to $2,000.


Right and wrong

Opponents of the project also claim that the estimated discharge associated with connecting sewer to the island has risen at least 40 percent - from 273,000 gallons per day to 424,500 gallons per day.

O'Regan said the initial number of 273,000 gallons per day was filed in the original application for the sewer extension permit with the DEP. The number, which is the average daily flow estimated for Plum Island, was submitted because the state agency in its permit application also asked for the average daily flow of the treatment plant. However, it was learned after filing the initial permit that DEP required maximum daily flow estimates for the actual project rather than average daily flow estimates. Therefore, a second permit was filed with the appropriate change, O'Regan explained.

Opponents of the project, including the Island Futures Group, filed an appeal, contesting whether the maximum daily flow could be added to the sewer extension permit. Essentially, opponents wanted the permitting process to start all over again, O'Regan said. In their appeal, opponents also questioned whether the DEP could set conditions on the treatment plant's permit.

However, opponents of the project were dealt a double blow this month when an administrative law judge ruled that the maximum daily flow could be added to the permit and that the DEP had no authority to set conditions on the plant's permit.

This summer, the city filed a motion to dismiss the appeal filed by the opponents based on lack of standing. However, the judge denied the motion to dismiss the appeal, ruling that the opponents did have standing as aggrieved persons.

As for the maximum flow rate, the judge returned the matter to the DEP to figure out, suggesting that the state entity collect information provided by the petitioners and the city before making such a determination.

"Once it does so, the matter can be returned to the Office of Administrative Appeals for a hearing on the correct maximum amount," wrote Administrative Law Judge James Rooney in his Oct. 10 ruling, "if petitioners are not satisfied with the figure ultimately determined by the department."

From a two-fold perspective, O'Regan also challenges claims made Monday night that the plant in the past has operated at above 80 percent capacity for at least 90 consecutive days.

"If you're above 80 percent capacity for 90 consecutive days, you have to begin the process of expanding the plant or getting the flows down," O'Regan said. "They may be correct if they're basing the information on the effluent meter, but that's the wrong meter to use. Even if somehow we were over the 80 percent criteria, which we're not, the rule says begin the planning process. Not only have we begun the planning process, we've down the follow up design and construction to get our flows beneath 80 percent.

"Even if they're right, they're still wrong, because we've met the obligation of the permit, which says either expand your plant or get your flows down - and we chose to get our flows down like most people would," O'Regan says.

Room for improvement

In the last six to eight years, more than $6 million in improvements have been made to the plant, including a $3 million project just completed last month in which a quarter of the city's sewer collection system was rehabilitated, resulting in a significant reduction in flows coming into the plant. Currently, O'Regan said flows coming into the plant range from around 2.0 million gallons per day to 2.3 million gallons per day, well below its 3.4-million-gallons-per-day capacity.

"We had a drought year in 2002, which resulted in the flows being lower than we expected on a regular year, but this year we had a relatively wet year," O'Regan said. "Preliminary indications are that the rehabilitation project has been very successful in reducing hundreds of thousands of gallons of flow."

As for other improvements, O'Regan said $1 million in upgrades to the plant's aeration tanks is in the works, which will break down the wastewater more efficiently. Furthermore, O'Regan said a study will be conducted to determine if modifications to the plant are needed. Another study will look at the presses to determine if there's a better way of getting the solids out of the system.

When asked about the status of the National Pollutant Discharge Elimination System permit, O'Regan said the EPA has yet to issue a draft permit. The plant is still operating under its old permit, which expired in 2002, and the process for a new permit has taken much longer than expected.

In the past, "It was a very simple process," O'Regan said. "This time, because there were certain issues raised, we had to hire consultants and lawyers and we have spent over $50,000 now on that - and that's something we would much rather spend on making improvements to the plant."

O'Regan emphasized that regardless of whether the Plum Island project moves forward, the Sewer Department is going to keep making improvements to the plant - improvements that have come as a result of the foresight of the Sewer Commission and not the forceful hand of some outside agency or court order.

"A capacity study done by Camp, Dresser and McKee showed that we could still handle the waste even without these improvements," O'Regan said. "But we're going to move forward with the improvements whether Plum Island takes place or not."

He also pointed to a study conducted in August 1972 from Coffin & Richardson examining the wastewater treatment plant, originally built as a primary facility in 1963 and upgraded to a secondary facility in 1984. The report stated that if Plum Island were to be serviced by a separate treatment plant, it should be sized to handle 0.39 million gallons per day, and the existing Newburyport treatment facility could be upgraded to handle a flow of only 3.01 million gallons per day. Those two numbers add up to 3.4 million gallons per day. Since the 1984 upgrade to the treatment plant, it can handle 3.4 million gallons per day.

For O'Regan, doing the math isn't complicated.

"This plant was always sized to handle Plum Island flows coming here," O'Regan said. "Even back in 1972, they knew that sometime Plum Island might be sewered and that it made sense to build a treatment plant so it can handle it."

When asked what his bottom line was about the plant's capacity, O'Regan responded, "There may be a need for a new plant whether Plum Island happens or not. If I knew the answer to that today, I shouldn't be a sewer superintendent in Massachusetts. I should be a gambler in Las Vegas or I should be on Wall Street on the stock market. If I can project today what's going to happen for sure - guaranteed - five or 10 years from now, that's where I should be.

"As far as the numbers and the way they're looking and normal growth, we should be fine for at least 10 years, probably closer to 20. But if we start having a large amount of growth coming in and if we don't take care of our collection system, we're going to have to re-evaluate that.

"People have said in the past, 'Well, we don't want to rehabilitate this, just build a new plant.' The DEP will not let you build an expansion until you've shown them that you've tightened up your collection system and that you're using what you have efficiently," O'Regan added.

"But based on what I know in the nine years that I've been here, do I think in the near future there's going to be a need to build a brand new plant? No, I don't."

 

 
 
(This article replicated online with permission of the Merrimack River Current.)
 
 
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