Perc Tests and Soil Evaluations in South Carolina

Called here: Site Evaluation (SCDES or Professional Soil Classifier) (this state no longer performs a literal perc test)

First verify whether public sewer is accessible, because SCDES cannot issue a new onsite permit where connection is available. Clear and mark boundaries and corners, stake the building, and mark the plumbing stub-out, tank, drain field, well, and other structures on the site sketch. Submit the application and $150 site evaluation fee. Under the standard path, SCDES evaluates the site and prepares the layout; under a private route, submit the required soil report and layout. SCDES decides whether site conditions support the requested permit. Do not construct, upgrade, expand, cover, or operate the system before the required permit, inspection, and approval. The installer arranges final inspection, and SCDES issues approval to operate after compliant installation and documentation. A permit generally remains valid for five years if the property and original conditions have not changed.

South Carolina uses a site evaluation, not a timed water-drop percolation test. Its current regulation does not use the words percolation test; the evaluation considers soil, geology, the seasonal high water table, and surrounding site features, with soil borings or backhoe pits as required and mandatory backhoe pits above the Fall Line. South Carolina also has no blanket acreage exemption: lot size alone does not remove the permit-and-evaluation requirement. SCDES may grant a written, case-specific variance or exemption from particular requirements when relief will not compromise health or environmental protection and site characteristics make strict compliance impractical or infeasible. A complete variance request is processed within three business days, but approval is discretionary and is not tied to acreage.

South Carolina's private-evaluator cost evidence is thin. Every applicant pays SCDES's flat $150 site evaluation fee, regardless of who performs the fieldwork. A PSC's fee is separate. A Department-contracted evaluator may charge no more than three times the state fee, so $450 is the legal ceiling for that specific referral arrangement, not a market average. R.61-56 states no equivalent ceiling for a privately hired PSC, and the firms checked did not publish South Carolina evaluation prices. Budget at least the $150 state fee and, if a private evaluator is required or chosen, get quotes from two or three professionals. Ask whether the evaluator is SCDES-contracted or privately engaged because that determines whether the $450 ceiling applies, and independently verify the license before hiring.

SCDES's permitting guidance says weather may affect processing times because saturated soil conditions negatively affect soil evaluations. SCDES does not publish a guaranteed statewide turnaround time, so plan for weather-related uncertainty rather than assuming a fixed number of business days. Hiring a licensed evaluator before applying, or hiring both an evaluator and a professional engineer to evaluate and design the system, may reduce application processing time depending on staff availability, but SCDES does not promise that result or provide a sourced statewide processing figure. Confirm current scheduling with SCDES and any private professional involved.

Under South Carolina's standard homeowner path, a certified SCDES staff member performs the site evaluation. A private evaluator is required after an SCDES evaluation does not pass for a conventional system or for a subdivision of ten or more lots without full utility access; otherwise private hiring is optional and may reduce processing time depending on staff availability. The private credential is Professional Soil Classifier (PSC), licensed by the South Carolina Department of Labor, Licensing and Regulation with advice from the Soil Classifiers Advisory Council. The rule also permits certain Professional Engineers and Registered Geologists to work within their own licenses without a separate PSC license. Verify a PSC through LLR's lookup and confirm service area directly; a roster address alone does not establish where a licensee works.

South Carolina Department of Environmental Services (SCDES), Onsite Wastewater Program · Verify a license