The aggregate materials present in the south half of Peerless Lake (NTS 84B) and in the north half of Lesser Slave Lake (NTS 83O) map areas were studied in 1985 to provide information on the distribution and characteristics of the resource. The study area is 1,300 kmï¿½ in size and was investigated at a reconnaissance level. The program consisted of: compiling existing information, air photo interpretation plus some site and laboratory analyses. Sand and gravel materials are distributed unevenly and are of variable quality. High quality, quartzite-rich preglacial sand and gravel commonly is present at elevations greater than 1,000 m in the area. Overburden is thin, volume probably is large and the material currently is unexploited. Further investigation is recommended. Major glaciofluvial kame and esker features located southwest of Whitefish Tower and south of Utikuma Lake are primary sources of aggregate material. Meltwater channels and outwash deposits in the west and northeast portions of the study area also are potential sources of aggregate. Glaciolacustrine coarse beach sand is located north of McMullen Lake. Recent sediments have little promise for aggregate exploitation.