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Burrows Yes There has been an increase in rodent activity since the last <br /> annual certification. Areas of previous activity (filled and <br /> compacted) were again burrowed, and additional areas <br /> have developed. No rodents were observed. The <br /> appearance of the burrows above the high water line <br /> suggest that the following species might be present: <br /> pocket gopher (Thomomys rnlpoides), prairie dogs <br /> (Cynomys spp), or Richardson ground squirrels <br /> (Spemtophilius richnrdsonii)(a dead Richardson ground <br /> squirrel was found in the pond in 1992). Three larger <br /> burrows, at and below the high water line, with entrenched <br /> runs in the bottom of the pond, suggest that muskrats <br /> (Ondntra zibethicus) are present. Due to the extent of <br /> burrowing activity, the locations of burrows were not <br /> plotted during this annual inspection. The width of the <br /> crest of the dam in the vicinity of extensive (ground <br /> squirrels and muskrats) and more threatening (muskrat) <br /> burrowing activity is approximately 10 feet. The muskrat <br /> burrows are located near or at low water levels <br /> (approximately five feet below the crest), in the range of 15 <br /> to 40 feet from the centerline of the crest. The extent of <br /> penetration of the burrowing activity through the dam has <br /> not been determined. No indication of seepage through <br /> the dam was observed. <br />Other Yes Erosion of the upstream face of the dam (at water level <br /> lines) has progressed at differing rates over the last five <br /> years. Some erosion is evident in an August 1989 <br /> inspection photograph. It appeared to have stabilized <br /> (good vegetation cover) in a July 1991 photograph. The <br /> October 1992 inspection report indicated a loss of some of <br /> the vegetative cover. The October 1993 report indicated <br /> that the vegetative cover was recovering. Horizon[al <br /> cutting into the face has now developed nearly a 2-foot- <br /> high vertical escarpment. The erosional scar is <br /> unvegetated. The crest edge has experienced minor <br /> wasting away. The intermittent erosion suggests that <br /> seeding in itself has been just slightly less than adequate to <br /> protect the embankment. <br />Structural: <br />Differential Settling No <br />Cracks or Slides No <br />Seepage No (The luxuriant growth of weeds observed in 1993 at the toe <br /> of the downstream slope, north of the primary spillway, <br /> was not evident during this inspection.) <br />Other No <br />Appurtenant Structures <br />Canadian Mine Pond # 1, Quarterly Inspection Report and Annual Certification, 24 October 1994 <br />Page 2 of 5 <br />