PDFWAC 173-160-430
What are the minimum casing standards?
(1) The casing may not affect or interfere with the chemical, physical, radiological, or biological constituents of interest. The casing shall be resistant to the corrosive effects of the surrounding formations, earth, and water and shall be impervious to any contaminants encountered.
(2) The casing shall withstand typical forces which act upon it during and after installation. All resource protection well casing shall conform to ASTM Standards, or at least 304 or 316 stainless steel, PTFE, or Schedule 40 PVC casing.
[Statutory Authority: Chapter 18.104 RCW. WSR 09-01-125 (Order 08-10), § 173-160-430, filed 12/19/08, effective 1/19/09; WSR 06-23-121 (Order 06-08), § 173-160-430, filed 11/21/06, effective 12/22/06. Statutory Authority: Chapter 18.104 RCW and RCW 43.21A.080. WSR 98-08-032 (Order 97-08), § 173-160-430, filed 3/23/98, effective 4/23/98.]