Environmental groups are challenging a state permit for a septic tank on Folly Beach amid worries the tank could leak into the ocean if the site erodes far enough.

The owner of the property said he's worried about erosion on Folly, too, and has done everything correctly in applying for the permit. 

Michael Corley of the S.C. Environmental Law Project said the state applies the same standards to septic permits on the coast as it would far inland, even though other development along the shore undergoes special environmental scrutiny.

That scrutiny also should be applied to septic systems, he said. 

"If we can’t keep sewage off the beach, what hope do we have of taking on the more difficult and comprehensive problems facing our coast?" Corley said. 

Septic tanks on Folly Beach are of particular concern to resident Matt Napier. The tanks serve nearly every home on the island and in some other beach communities even as they're vulnerable infrastructure that could create a contaminating mess in a serious storm. 

Napier argued the rate of erosion around the lot where the state has approved a new tank is so fast that it could easily be overwashed. The lot is the last one before the public park on Folly's east end, which is the fastest-disappearing part of an already vulnerable island. 

The buildable area of the lot is buffered by a rock revetment that is covered with sand after renourishment projects, but that wall has been uncovered before between deliveries of more sand, according to satellite images. 

"There is a zero percent chance it would have been approved before the renourishment this year," Napier said. 

Stephen Rawe, who owns the lot and one immediately behind it that already has a house, said he's done everything correctly in applying for his septic permit. 

His application shows a site drawing that includes a tank in the back part of the lot, where there are currently dunes, and a small house closer to the beach. Rawe said he doesn't have any plans to put anything on the lot soon — the timeline depends on the state of the economy, he said — and local officials confirmed he had not submitted any building plans to the city for review. 

"I've been out here 40 years and have great concern for the erosion of Folly Beach, and we obey all the rules and try to preserve the beach as best we can," Rawe said.

Septic tanks are among a host of land-use issues being discussed on Folly as officials try to develop a package of regulations for waterfront land along both the marsh and beach sides of the island. 

Those rules could end up affecting Rawe's future plans. One proposal would require new septics to be placed as far from the beach as possible within a lot. Another would allow development only on lots that have at least 10 feet of frontage on a public road — a stipulation that Rawe's lot, which is mostly surrounded by other private property, barely meets. 

Regardless of future city rules, Corley sees the case as crucial to future coastal projects. Similar to another ongoing SCELP effort to get the state to remove six homes from an eroding shore in Beaufort County, Corley said the Folly case will set an important precedent moving forward as sea level rise only exacerbates coastal erosion. 

"I see Folly as a forerunner for the rest of the coast," Corley said. "You're seeing these hot spots flare up, and we think they're going to become more common."

Bubbling beaches? South Carolina oceanfront septics cause stink

Reach Chloe Johnson at 843-735-9985. Follow her on Twitter @_ChloeAJ.