Page 27a: Two Greyscale Photos [5/8/75] Downstream right abutment and zone 1 showing workmen cleaning up the abutment for 1 material. [6/16/75] Right keyway station 4+20 showing caves in downstream wall bring back filled with concrete using crane and 2 cu. yd. bucket. Page 27b: Two Greyscale Photos [7/17/75] View of the right abutment key trench, station 8+50, looking towards auxiliary outlet works tunnel access shaft and spillway inlet. [7/9/75] Right abutment keyway trench being backfilled with compacted Zone 1 material.