Hydrogeology of the Clear Hills-Chinchaga River area, Alberta

The 20-year safe yield for about four-fifths of the area is 0.1 to 0.4 l/sec (1 to 5 igpm). Only in small isolated alluvial areas along the Peace River is the potential yield greater than 8 l/sec (100 igpm). Tertiary and Quaternary sands and gravels are capable of yielding 0.4 to 2 l/sec (5 to 25 igpm), most notably at Whitelaw. Along the northeastern margin of the area, the Dunvegan sandstone may yield 0.4 to 2 l/sec (5 to 25 igpm). A 20-year safe yield of even 0.1 l/sec (1 igpm) is not probable in portions of the area's lowland and along the steep slopes of the upland. Generally, the relatively productive and conveniently located aquifers are composed of surficial deposits. Marginal aquifers may be the Lower Kaskapau, Dunvegan and the Wapiti Formations. The former, however, proved to be unsatisfactory at several places, and the latter is situated in an unpopulated upland.

The shallow groundwater is of good chemical quality over most of the central and northern parts of the area. This water is a calcium or sodium bicarbonate type and generally contains 500 mg /L or less total dissolved solids. Shallow groundwater quality is less than satisfactory in extensive areas in the south due to a high dissolved solids content (2000 to 4000 mg/l), high sulfate concentrations, or both. The quality of the formation waters is undesirable. These waters are of sulfate or chloride type with total dissolved solids concentrations up to 30 000 mg/l.