House Bill H643-Injection of Wastewater
Onslow Water and Sewer Authority is pushing a bill in the N.C. General Assembly that would allow it to pump treated sewage into the ground, overturning a longstanding law protecting vital drinking-water sources and potentially posing a significant health risk to the thousands of Onslow County residents who depend on clean groundwater for use in their homes and businesses.
Because of the risks, injecting treated sewage into groundwater is currently illegal in North Carolina. But Rep. Russell Tucker (D-Duplin) introduced House Bill H643, which would allow operators of any sewer system in the state to apply for permits to inject treated sewage – called “reclaimed water” in the bill -- into aquifers for “temporary” storage. ONWASA proposed the bill and hired an expensive lobbyist, Sandy Sands, to push its passage. The bill is awaiting a hearing before the House Committee on Water Resources and Infrastructure.
As population growth continues to deplete groundwater sources throughout the country, injecting treated surface water or drinking water into the ground to recharge aquifers is becoming more common. At least 48 states, however, ban or discourage using treated sewage for that purpose.
Even using more benign treated surface water or drinking water has its risks.
• The National Research Council, part of the National Academies of Science, found in 2001 that using chemically treated surface water posed a significant risk to groundwater quality. The report noted that treated water could still contain a higher concentration of bacteria and contaminants than the native groundwater. The study also found an increase of heavy metal concentrations, including mercury.
• The Army Corps of Engineers found arsenic levels exceeding safe drinking water standards in areas where surface water or drinking water was injected into the ground.
• The U.S. Geological Survey found that less than 25 percent of injected water would be available for reuse after studying a proposed project in South Carolina, suggesting that pumping treated wastewater into an aquifer may risk contaminating drinking water for very little potential recovery.
If the groundwater is contaminated, there is currently no law in North Carolina that requires nearby private well users to be notified. Even the best wastewater plants have treatment failures, and once it’s in the aquifer, there’s no getting it back out.
State agencies recently permitted two N.C. cities, Greenville and Wilmington, to pump treated drinking water into the ground to recharge aquifers.
The legislature needs to kill this flawed bill. If they intend to embark on this hazardous path, legislators should first appoint a study committee to answer several critical questions:
• What type and degree of water treatment is necessary to ensure that no pathogens will survive in groundwater?
• Will disinfectants such as chlorine lead to the formation of carcinogenic compounds that will move to broader groundwater areas?
• What information is needed to ensure that the water being recharged is geochemically and microbiologically “compatible” with native groundwater? Unanticipated reactions may lead to poor-quality water, biomass formation, pathogen growth and well clogging.
• What monitoring is required to ensure that unforeseen water quality problems don’t affect broader groundwater resources? Who will pay for it?
• What are the impacts of on property values? On land-use patterns?
Until questions such are those are answered, we should assume that pumping treated sewage into our aquifers poses a significant health risk.
We have asked ONWASA to pull H643 and ask the legislature to assign a study committee to the task of investigating potential benefits and risks and make recommendations to the next legislature. A bill to create such a committee was considered by the legislature in 2007 but never passed.