Industrial mineral site no. 1486, known as "Penley Lake" is a site in Okanogan County, Washington. This site has been associated with sodium sulfate. A notation found in DGER Bulletin 37 on page 96 says "Area of 11 acres. Contains 24,350 tons of mixed crystalline salts, of which 23,700 tons are sodium sulfate. Brine contains 8,000 tons of mixed salts, of which 7,000 tons are sodium sulfate", and designates the value as "Warrants investigation".