<html> <head> <title>Rule 74:54:02:18 Ambient water quality determination.</title> <META NAME="Keywords" Content="Administrative Rules 74:54:02:18"> <META NAME="Description" Content="Administrative Rules 74:54:02:18 Ambient water quality determination."> <meta name=Generator content="Microsoft Office HTML Filter 2.0"> <meta http-equiv=Content-Type content="text/html; charset=windows-1252"> <meta name=Originator content="Microsoft Word 10"> <style> <!-- --> </style> </head> <body lang=EN-US> <div> <p><font size=3 face="Times New Roman">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <b>74:54:02:18.&nbsp;&nbsp;Ambient water quality determination.</b> 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.</font></p> <p><font size=3 face="Times New Roman">&nbsp;</font></p> <p><font size=3 face="Times New Roman">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 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.</font></p> <p><font size=3 face="Times New Roman">&nbsp;</font></p> <p><font size=3 face="Times New Roman">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 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.</font></p> <p><font size=3 face="Times New Roman">&nbsp;</font></p> <p><font size=3 face="Times New Roman">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <b>Source:</b> 14 SDR 86, effective December 24, 1987; transferred from §&nbsp;74:03:16:17, July 1, 1996.</font></p> <p><font size=3 face="Times New Roman">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <b>General Authority:</b> SDCL <A HREF="/statutes/DisplayStatute.aspx?Type=Statute&Statute=34A-2-28">34A-2-28</A>, <A HREF="/statutes/DisplayStatute.aspx?Type=Statute&Statute=34A-2-30">34A-2-30.</A></font></p> <p><font size=3 face="Times New Roman">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <b>Law Implemented:</b> SDCL <A HREF="/statutes/DisplayStatute.aspx?Type=Statute&Statute=34A-2-22">34A-2-22.</A></font></p> <p><font size=3 face="Times New Roman">&nbsp;</font></p> </div> </body> </html>