BRUNSWICK COUNTY — The number one question H2GO board member Steve Hosmer hears from the public is how the authority will provide enough water to customers based on the rapidly growing county.
READ MORE: H2GO pumping PFAS-free water to 40K customers, but some still wary
ALSO: H2GO says PFAS-free aquifer plant will be up and running by next year
The population of Brunswick County increased 32% between 2010 and 2019, marking it the fastest growing county in the state. H2GO is currently treating 3 million gallons of water per day but can handle up to 6 million gallons per day for its 45,000 customers in Leland, Belville and some unincorporated areas of the county.
“The most common question used to be: ‘Is the water clean or safe yet?’” Hosmer told Port City Daily.
H2GO launched a PFAS-free aquifer-based reverse osmosis water plant this year to tackle the pollution. While capacity was built into the new $42-million project, H2GO predicts it will reach daily peak demand, 6 million gallons per day, by 2027. So the board is preparing for the future by advocating for aquifer storage and recovery, a less expensive option to meet demand.
ASR is the direct injection of treated, drinkable water into the ground, which is safely stored until it needs to be pumped out for use. Using ASRs are more economical than above-ground RO skids, or processing units. Additional underground wells will add resiliency and capacity to H2GO’s current supply.
“These operations forgo the necessity to build and maintain traditional storage tanks to hold treated water, as the aquifer itself functions as a means of storage,” North Carolina Department of Environmental Quality spokesperson Laura Oleniacz told Port City Daily.
Also, there is no need to purchase more tracts of land and the underground storage adds useful life to the current RO plant, saving additional funds and delaying upgrades.
The use of an aquifer-sourced water has been contentious for over a decade, with various H2GO boards waffling in support and opposition. The project even led to a lawsuit between Belville and Leland, which took nearly four years to get sorted out, in the meantime freezing the utility authority’s assets until 2021.
Meanwhile, Hosmer has been fighting for using the aquifer system since 2017, forming a grassroots effort, Clean Water Team to challenge the H2GO board at public meetings. He was elected to the board in 2019 and has been at the forefront of bringing the project to fruition.
READ MORE: Case closed: H2GO pays Belville $100K in legal fees, brings years-long settlement to end
Hosmer said that once the water authority increases its storage capacity with ASR wells, the need to expand capacity with additional construction can be put off for years, helping to keep water costs lower. H2GO currently plans to create three ASR well sites with two wells on each site. The total storage available from those would provide up to 75 days of water to customers if something were to cause the RO plant to be out of service.
H2GO draws its drinking water from wells up to 600-feet deep, sourced from the Lower Peedee and Black Creek aquifers; the two have a combined ability to store 100 million gallons of water using the ASR well sites. Hosmer said H2GO estimates the solution could enable H2GO to handle peak demand for another eight to 12 years with its current RO configuration — based on an average 6% annual growth trend of customer base — before having to add more expensive processing capacity-building solutions.
The estimated cost to build an above ground storage tank with a 1-million-gallon capacity is $3 million. By comparison, it’s cheaper per gallon to utilize ASR wells; it would cost about $5 million to store approximately 100 million gallons of water.
In other words, the above ground storage is 60 times more expensive per gallon of water.
“Instead of physically building a structure, ASR makes use of the underground structure that already exists — the naturally-occurring aquifers,” Hosmer said.
One ASR well site will be developed initially where two wells and pumps would have to be installed. The exact price is not yet available. Hosmer said two additional ASR well sites will eventually be added, need and budget pending.
Most utility companies using an ASR system will siphon water during low-usage months for storage and draw it back out of the ground when it’s needed.
Currently, H2GO is using only roughly 3 million gallons per day, so with a 6 million-gallon-per-day capacity, it has room to reserve 3 million gallons per day into the wells.
Hosmer said H2GO is using two existing 6-inch wells that were drilled in 2013 for testing. The existing wells were originally used to estimate production capabilities for the RO system now in place.
“Since those tests, these wells have been standing idle while the aquifer-sourced reverse osmosis system was completed,” Hosmer said. “Now we are making new use of those wells again by using them to run the injection/withdrawal tests needed to help us design our future, full-service ASR wells.”
Tests should begin within the next few weeks, he added.
NCDEQ would have to approve an injection permit for the construction and operation of an ASR. Prior to issuing a permit, H2GO would have to complete water quality analyses of the water to be injected and stored, as well as the source water from the aquifer.
It also must model any potential reactions between the injected water and source water to ensure there are no unforeseen chemical reactions. This could result in deposits of minerals known as “scaling,” according to Oleniacz.
“Injected water may contaminate the aquifer with unknown emerging compounds, and the water is difficult to remediate once underground,” she added, which is why prior testing must be done.
However, the aquifers used by H2GO have “confining layers” — acting as a shield to protect stored underground water from surface water contamination seeping in, Hosmer explained.
The reason H2GO is equipped to use ASR wells is because it’s starting out with non-contaminated water coming from the same aquifers that will be stored, he added.
“The only contamination is salt, a naturally occurring element,” Hosmer said. “The clean aquifer water has no industrial contaminants to begin with so not even trace amounts of GenX and PFAS will be in the water.”
The wastewater coming off the RO screens contains the amount of salt equal to the annual average salinity in the Brunswick River, so it’s not increasing or decreasing the content.
Statewide, there are currently no active ASR wells, which would make H2GO’s the only one, Oleniacz confirmed. Though one was constructed in Pitt County in 2004 and tested in 2011 to 2012; it’s now offline.
Another inactive well from 2011 is located in New Hanover County. Cape Fear Public Utility Authority took the ASR — storage capacity of 150 gallons — offline in 2017 following the discovery of PFAS in the aquifer, spokesperson Cammie Bellamy said.
CFPUA had launched a pilot project to inject the ASR well with treated drinking water from the Sweeney Treatment Plant. At the time, the facility did not have PFAS-removing technology.
“We do not currently have plans to bring the ASR back online, but will continue to work with our partners at NCDEQ to evaluate a potential future use option for the aquifer,” Bellamy said.
ASR wells are better suited for sandy aquifers found in North Carolina’s coastal plains than in hard rock found in mountainous regions. Sandy conditions have more storage capacity, Oleniacz confirmed; water is stored in joints and fractures in rocky areas, resulting in lower water yield.
The neighboring state of South Carolina has successfully used ASR wells in Horry County and Florida also has more than 20 ASR facilities. Nationwide there were more than 100 ASR locations as of 2018.
Tips or comments? Email amy@localdailymedia.com.
Want to read more from PCD? Subscribe now and then sign up for our morning newsletter, Wilmington Wire, and get the headlines delivered to your inbox every morning.
