S.D. Admin. R. 74:54:02:18
The ambient water quality contaminant concentrations shall be determined prior to and specified at the time the groundwater discharge permit is issued provided that no data prior to March 27, 1973, exist.
New facilities submitting applications for groundwater discharge approval after the effective date of these rules shall, at a minimum, collect four groundwater samples from each applicable well within site boundaries over a six-month period with no two samples taken in the same month. The arithmetic mean plus one standard deviation of the sample data shall represent ambient water quality at the time of permit issuance. Thereafter, ambient water quality contaminant concentrations shall be updated to reflect natural fluctuations in concentrations by including applicable up-gradient, on-site groundwater monitoring data for the biennial water quality permit variance review.
Existing facilities discharging before or within 120 days after the effective date of these rules shall collect groundwater samples from applicable up-gradient wells within site boundaries. The arithmetic mean plus one standard deviation of applicable parameters shall represent ambient water quality at the time of permit issuance. Thereafter, ambient water quality contaminant concentrations shall be updated to reflect natural fluctuations by including applicable up-gradient, on-site groundwater monitoring data at the water quality variance biennial permit review.
S.D. Admin. R. 74:54:02:18
General Authority: SDCL 34A-2-28, 34A-2-30.
Law Implemented: SDCL 34A-2-22.