New septic system technology to clean Cape Town’s waters



As Jennifer Loughran led a tour of the Barnstable Clean Water Coalition’s Shubael Pond Project, she called a newly installed NitROE sewage septic system a “living laboratory.”

“Maybe looking at a septic system isn’t always exciting,” said Loughran, project manager at the coalition. “But just thinking about the possibilities these systems offer is mind-blowing. “

Zenas Crocker, executive director of the coalition, noted that across Cape Cod, “80-85% of water problems are related to septic tank problems. We believe that this system will be one of the key solutions to clean the waters of the region. “

The coalition, formerly Three Bays Preservation Inc., is working to provide 15 NitROE systems to the Shubael Pond neighborhood of Marstons Mills as part of a collaborative project with the Town of Barnstable and others that include the Protection Agency. United States Environmental Protection Department, Massachusetts Department of Environmental Protection. , the US Geological Survey and The Nature Conservancy.

The project is part of a two-year pilot program designed to test and monitor the system’s ability to reduce nutrients in groundwater in the region. The project will also identify problems related to storm water.

The initiative is one of the few that the Barnstable Clean Water Coalition is pursuing, with the help of grants and environmental departments and organizations, to make a difference in Cape Cod’s water clean-up efforts. While cities are in various phases of wastewater planning that could take years to complete, alternative technologies are being pursued at the same time – potentially making a difference sooner and in some areas. What works at Barnstable could have applications elsewhere.

A new “elegant” system

Although the concepts behind the Shubael Pond project began in 2019 – in an area already troubled by intermittent water quality issues that have closed ponds in the area – the NitROE has received a permit of approval. provisional from the Massachusetts Department of Environmental Protection in June. Starting in August, the coalition installed six NitROE units in the 350 household area that contributes to the Marstons Mills subwatershed, all at the expense of the coalition. With the Title 5 septic system modernization and complete replacement procedures, the cost was between $ 20,000 and $ 30,000 per parcel of land.

Crocker calls the NitROE system, developed by a local company called KleanTu, “elegant in its simplicity”. The machine, which can fit into an existing Title 5 septic system, is located between the septic tank and the leech chamber, where it focuses on removing nitrogen, carbon and suspended solids.

The 2,000 gallon NitROE tank relies heavily on gravity and small amounts of electricity for its air pump, and has two sections – the first a limestone aeration chamber, which converts ammonia to nitrate; and the second containing wood chips, which converts nitrate into nitrogen gas.

With sampling ports also located closer to the ground surface, the project can also focus on emerging contaminants, including around 200 different chemicals, Crocker said.

According to coalition statistics, current Title 5 septic systems in use in Cape Town remove only 20-30% of the nitrogen generated. % to 90% of nitrogen generated by systems.

“We don’t think this will replace any sewer expansion – there are high density areas and commercial sites for buildings that still need municipal treatment,” Crocker said. “But we are focused on delivering nature-based solutions without waiting for municipal treatment that could take 20 to 30 years to get to this area.”

If the data confirms that the NitROE systems can keep nitrogen levels in the region’s groundwater below about 10 milligrams – a number Crocker calls “the gold standard” – the coalition may seek “approval. general use “. This type of approval could eventually bring NitROE systems to Cape Town cities, integrating them into wastewater management plans.

The proponents say this strategy could have an impact on the health of lakes, streams, estuaries and waterways in the region.

Start new discussions

Brian Baumgaertel, senior environmental specialist and director of the Massachusetts Alternative Septic System Test Center in Buzzards Bay, said the data “looked promising” before the Shubael Pond project began. It provides technical support to the coalition and develops individual monitoring protocols for the pilot program.

NitROE systems were originally developed by KleanTu at the test center, where the technology was refined with a grant provided by the Massachusetts Clean Energy Center. Baumgaertel said he was part of the process for about five years.

“We sampled the NitROE here as a third party – and we’ve seen a lot of data from the field that indicates the system is working fairly well,” Baumgaertel said. “Certainly compared to many other innovative alternative technologies. “

Historically, Baumgaertel explained, first-generation alternative septic systems did not perform “much better” than existing Title 5 septic systems and were expensive to install and maintain. With the most recent versions of innovative alternative systems, he said, homeowners can move – at a fraction of the cost – to a range of what processing plants are capable of.

This device is used to monitor the water quality in Shubael Pond at Marstons Mills by the Barnstable Clean Water Coalition.

“Because older technologies didn’t work at this level, I think a lot of cities were starting to write off the technology as an option,” Baumgaertel said. “But I think at this point the NitROE system and the Shubael Pond project have started new discussions about how all of these systems are helping people.”

As the coalition works at Barnstable, Loughran said it’s important to remember that water quality isn’t just an issue at Barnstable. “We are all independent cities and we will do independent things to help our own cities, but when it comes to the health of our water, we have to be in the same boat,” she said.

“No time to wait”

Barnstable County Commissioner and Yarmouth Breeder Mark Forest recently visited the Shubael Pond Project and said Cape Town as a whole needs to ‘invest a genuine interest’ in the work of the Barnstable Clean Water Coaltion.

“The real focus is where can we expand our role in the county to help support more of these projects – which is what we want to do,” Forest said. “We need to validate the performance of an innovative technology, and essentially we need to have an organization in place that has significant credibility with regulators. Because at the end of the day, it will be the regulators who will make the decision whether or not to allow alternative septic system technology. “

As new septic system technology continues to prove itself, Baumgaertel said, Cape Town cities are already starting to re-examine the integration of systems like NitROE into city-by-city wastewater management plans.

Wellfleet’s wastewater management plan, for example, “relies heavily” on the use of innovative systems, he said, and Falmouth plans to use such systems in parts of the city with its large sewage system.

Although the Town of Barnstable is working with the coalition to incorporate alternative approaches to wastewater treatment, Bill Weston, 78, a resident of Marstons Mills and a participant in the Shubael Pond project, said there was “no time to wait for the Town of Barnstable Complete Wastewater Management Plant. – a plan in several stages over 30 years estimated at 1.4 billion dollars.

“Everyone knows there’s this 30-year plan, but I think something needs to be done before that,” he said. “I lived 50 years on Cape Cod and the number of people has tripled so as a result the amount of pollution comes with it. If something is not done quickly, we will go to the point of no return.

Shubael Pond and other Cap kettle ponds already facing intermittent summer shutdowns due to PFAS contamination and cyanobacteria-inflamed algae blooms, he said, leaders of the city have to “find a better way quickly”.

PFAS, or per- and polyfluoroalkylated substances, are a group of thousands of man-made chemicals linked to health problems ranging from immune system problems to cancer.

NitROE technology “seems to be state of the art and I think that is a game changer,” Weston said. “I’m glad the coalition is doing something – they’re taking a logical step and I’m happy to see how it turns out.”

Despite the compelling initial data, Crocker said, there is “no silver bullet” for the contaminants already present in the region’s groundwater. He said he would work closely with the EPA’s research and development office, which has a network of monitoring wells that will begin to project changes in groundwater quality as systems neighborhood septic tanks will be deployed.

“The work of the EPA is critical to understanding how NitROE technology will impact the region’s water supply systems,” said Crocker.

A cranberry bog project

As the pond project progresses and those involved wait for data, the coalition is pursuing other water sanitation initiatives as well. One concerns restorations of cranberry bogs.

With a recent grant of $ 750,000 from the EPA’s Southeastern New England program, coalition deputy director Casey Chatelain said the organization can begin to develop a pilot restoration program. 56-acre peatland, which will include water sampling at 10 stations along the Marstons Mills River.

Because every peatland restoration is different, based on a myriad of goals and projected outcomes, Chatelain said, she will work with local cranberry growers to discuss conservation easements and possible peatland buybacks.

Still in its infancy, peatland restoration is the first pilot watershed grant in history, with the coalition receiving $ 150,000 per year for five years. For Chatelain, who will be the spearhead of the pilot project, the “main driver” of peatland restoration is to improve water quality, but also to raise awareness through advocacy and education.

“A lot of people look at the water and see nothing wrong with it, but we need more people to advocate for clean water,” she said.



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