South Carolina Private Well Water Quality 2026

Military PFAS Contamination: The Primary Well Water Threat

South Carolina has a significant concentration of military installations — and at least four of them have been confirmed as contaminating surrounding groundwater with PFAS from decades of aqueous film-forming foam (AFFF) firefighting use. A 2019 Post and Courier investigation, based on previously undisclosed Air Force studies, found Shaw Air Force Base, Joint Base Charleston, the North Auxiliary Airfield, and the former Myrtle Beach Air Force Base were all saturated with PFAS — with some groundwater readings thousands of times above EPA advisory levels at the time.

Shaw Air Force Base (Sumter County) is the most documented source of private well contamination. The Department of Defense confirmed in September 2023 that Shaw’s activities have contaminated off-base residential wells. An EWG analysis of DoD data from late 2023 identified 205 wells near the base testing above the EPA’s 4 ppt standard — but below the old 70 ppt threshold, leaving hundreds of residents in a regulatory grey zone. By 2024, the remediation picture had grown significantly: the Shaw AFB environmental programme reported over 1,120 properties in the surrounding area had been surveyed, with more than 250 drinking water wells tested. Testing across 2019–2023 had found PFAS levels in some water supplies doubling or tripling the 70 ppt advisory limit. The Air Force has provided bottled water to residents with results above 70 ppt and is installing Point-of-Use Treatment (POUT) filters for affected properties.

Joint Base Charleston is ranked by EWG among the ten most PFAS-contaminated military bases in the United States. In 2018, Air Force testing found groundwater on base with combined PFOA and PFOS levels of 1.15 million parts per trillion. Independent sampling of a stream draining from the base runway recorded 2,997.6 ppt of PFAS — flowing directly towards the Ashley River approximately 4,000 feet away. Contamination has been confirmed in multiple areas of soil and groundwater on base, with surface water impacts extending into the surrounding waterway network.

Fort Jackson (Richland County, Columbia area) is a designated EPA Superfund site, with documented contamination including PFAS, RDX explosives residue, TCE and PAHs in soil and groundwater. Whole-house filtration has been supplied to some affected residents near the base perimeter. McEntire Air National Guard Base (Richland County) reported 16 wells above 4 ppt, and Marine Corps Air Station Beaufort reported a further three.

South Carolina has no state-level PFAS maximum contaminant levels of its own. The state relies entirely on the federal EPA rule, which applies only to public water systems — not private wells. Private well owners are entirely on their own for testing and treatment.

PFAS in South Carolina Surface Water — A Statewide Picture

The contamination problem extends well beyond military fences. Starting in 2022, SCDES began presenting results from its Ambient Surface Water Monitoring Project — a programme approved in April 2021 that tests more than 100 streams, rivers, lakes and coastal sites across the state for over two dozen PFAS compounds quarterly. PFAS have been detected at nearly all sites tested, with concentrations highly variable but many sites exceeding the EPA’s proposed 4 ppt limit. A peer-reviewed study sampling 40 locations across the state found 38 of 40 contained detectable PFAS. A 2022 Waterkeeper Alliance report identified South Carolina as one of six US states with the highest concentrations of PFAS in surface water.

This matters for private well owners because PFAS-contaminated surface water can infiltrate shallow wells — particularly in the Sandhills region and Coastal Plain where geology favours downward migration of surface contaminants into aquifers.

The Sandhills Region: A Zone of Elevated Risk

South Carolina’s Sandhills region — a band of ancient dune geology running through the midlands of the state — presents a distinct and serious groundwater vulnerability. According to SCDES, the Sandhills area has unusually high surface water infiltration rates due to its porous, sandy soils. Wells here are typically shallow and tap unconfined aquifers, which are directly susceptible to contamination migrating from the surface and through the soil.

Compounding this geology, the Sandhills region has a high density of older septic systems — many predating current regulatory standards — that were built too close to residential wells. SCDES has specifically identified this area as a priority zone for PFAS testing, noting that older septic fields can act as a direct pathway for surface contaminants to reach groundwater. Fort Jackson and McEntire ANG Base both sit within or adjacent to this region, adding military contamination risk to an already geologically vulnerable landscape.

Arsenic and Manganese in Coastal Plain Wells

Beyond PFAS, the South Carolina Coastal Plain presents a documented arsenic risk in private wells. A peer-reviewed study of Georgetown County well water found that while only 2% of samples exceeded the mandatory EPA limit of 0.05 mg/L, 72% exceeded the stricter health guideline of 0.01 mg/L (10 ppb). The same study found manganese exceeded mandatory limits in 37% of wells tested, and iron was elevated in 88% of samples — largely responsible for high turbidity in nearly half the wells sampled. SCDES notes that arsenic risk often correlates with well water pH above 8.5 in South Carolina aquifers.

Arsenic is colourless and tasteless — it cannot be detected without laboratory testing. Long-term exposure is associated with cancers of the kidney, bladder and skin, cardiovascular disease, and nerve damage. SCDES recommends arsenic testing for all private well owners, particularly those in Coastal Plain counties.

Nitrate and Bacteria Risks

In South Carolina’s agricultural lowlands — particularly the Pee Dee Basin — nitrate contamination from fertiliser runoff poses a documented risk to shallow private wells. Nitrate above 10 mg/L (the EPA MCL) is dangerous for infants under six months, causing methemoglobinemia (blue baby syndrome). Agricultural areas with intensive row cropping carry the greatest nitrate risk for nearby well owners with shallow wells.

Bacterial contamination (coliform, E. coli) can enter wells through cracked or poorly sealed wellheads, flooding events, and nearby failing septic systems. This risk is elevated throughout the Sandhills and Lowcountry, where older infrastructure and high groundwater infiltration rates combine. Annual testing for bacteria is the minimum recommended by SCDES for all private well owners.

Regulatory Situation for South Carolina Well Owners

Private residential wells in South Carolina are not covered by the Safe Drinking Water Act or its state equivalent. SCDES regulates well construction and permitting under Regulation R.61-44, but has no authority to test or mandate testing of water from completed private wells. There is no requirement for regular testing and no notification system when contamination is detected near a well.

South Carolina has no state-level enforceable PFAS maximum contaminant levels. The state relies entirely on the federal EPA rule — 4 ppt for PFOA and PFOS — which in any case applies only to public water systems. SCDES does offer a free voluntary PFAS testing programme for private wells, funded by a $10 million state PFAS allocation made by the legislature in 2022, prioritising areas near suspected pollution sources. Participation is voluntary and capacity is limited — SCDES accepts requests via its website.

One practical note: SC residents over 65 or receiving public assistance are entitled to one free annual coliform bacteria test and one free metals and minerals analysis through SCDES. All other well owners pay standard lab fees — approximately $75–$200 for a basic bacteria and nitrate panel, with comprehensive panels in the $200–$400 range.

Check our South Carolina municipal water quality page for city-by-city tap water data, or use our live boil water notice tracker for active advisories across the state.

Known High-Risk Areas in South Carolina

If you live near any of the following locations, well water testing is urgent — not precautionary.

How to Test Your South Carolina Well Water — and What to Do Next

Given South Carolina’s combination of confirmed military PFAS sources, Coastal Plain arsenic risk, and Sandhills geology, every private well owner in the state should test their water regardless of whether they live near a named contamination site. PFAS is colourless, odourless and tasteless; arsenic and manganese are undetectable without testing. Contamination can be present at harmful levels with no visible or sensory warning.

Start by contacting your local county health department or visiting SCDES at des.sc.gov to find a certified laboratory and check whether your area qualifies for the state’s free voluntary PFAS testing programme. If you live near Shaw AFB, Joint Base Charleston, Fort Jackson, McEntire ANG Base, or the former North Auxiliary Airfield or Myrtle Beach AFB sites, treat PFAS testing as urgent.

For filter options, our well water filter guide covers reverse osmosis systems for PFAS, arsenic and manganese, UV disinfection for bacteria, and whole-house well systems for comprehensive treatment. You can also browse our full water filter solutions page or check your ZIP code for local water quality context.

For other Southeast well water risks, see our pages on Georgia wells and North Carolina wells. Return to the private well water directory to find your state.