EM surveys maps : South Bay Mine site : final report 1995.

Abstract

The February 1995 survey was carried out over essentially the same grid as was established in March 1992. This year, two lines were added at both the east and west ends, and the complete grid surveyed with receiver - transmitter coil separations of 10 m, 20 m and 40 m. In the March 1992 survey, only 10 and 20 m coil separations were used. The 1992 results are presented on Maps MS-1 to MS-3 and the 1995 results on Maps MS-4 to MS-8. Differences between two sets of results are on MS-9 and MS10. Although the 1995 survey recovered the same 10 anomalies initially identified in 1992, differences in both horizontal and vertical positioning, as well as changes in the levels of conductivity, imply that significant changes have occurred in the groundwater regime in the area of the Mine Site. Some of these changes appear to be directly related to the presence of the Backfill Raise Diversion Ditch which was constructed shortly after the 1992 survey.