REP15581

• Permit No: M1977378
• IBM Index Class Name: Report
• Doc Date: 8/10/1982
• Doc Name: SANITARY LANDFILL 2 MANAGEMENT AND OPERATION PLAN
• From: UTE ENGINEERING AND SURVEYING CO
• To: TOWN COUNTRY COORDINATOR
• Media Type: D
• Archive: No

The Landfill Operator, under supervision of the Town of SiLverton,
' will be required to police the access road and the highway from
Silverton to the landfill site.
Site Geolo and Soils. The landfill site is located on a:n alluvial
' fan at t e southern ase of Storm Peak at elevation 9,440 :Feet. The
al uvial fan is of unknown depth but is estimated to be in excess of
50 feet. It overlies the Eureka Rhyolite formation which :in turn
overlies Precambrian Rock. T e Animas River flows in the •~allev Boor
about 30 feet below the e. Refer to e ollo~aing map
showing eneral Geology of the area for more details, and to
Appendix A for a copy of a Geotechnical Investigation of tailings
pond no. 3, the proposed landfill site, prepared by Fox in Rpril, 1976.
Test holes in the landfill site in addition to the holes d:cilled by
F.px in 1976, were dug with the Town backhoe on July 15, 1982. The
holes, a total of four (4), extended to depths of approxim,stely seven
(7) feet. The locations of the test holes are shown on the=_
' Togography Map, page 19. Data obtained from the excavation is as
follows;
' TEST HOLE: 1 2 3 4
ELEVATION 9,442 9,440 9,441 9,441
DEPTH (feet) 7 3 5.5 5.5
SAND (feet) 7 0 0.5 to 3.5 see below
' SLIMES (feet) none 1.2 1.5 to 4.5 4.5
NOTES: Test Hole No. 1: Dug to 7 feet. Generally all well drained
sa wit small, isolated lenses of clay. Material stable
and well drained. Backsloping of 1:1 required for trench
excavation. No free water.
' Test Hole No. 2: Dug to 2.6 feet. Hole was located on extreme
edge of clay surface. Dug through 1.2 feet of slimes and
' encountered well drained sand. Correlates well with hole No.l.
Test Hole No. 3: Surface was well drained sand. Northern part
o t e trenc length of 10 feet, had 6-inches of sand over
clay. Southern part of trench had 3.5 feet of san3 over clay.
Dug to 5.5 feet, hole kept filling with wet clay, no indication
of extent of clay.
' Test Hole No. 4: Surface was well drained sand. Excavation
s owe foot of sand, 4.5 feet of clay, and sand again.
' Unable to excavate deeper. Clay appers limited in extent
and could be moved during operation of the landfill.
Conclusions from test hole excavation. Considering the location of
' clay and sand found in each hole, compared with the assumed cross-
sections shown by Fox, we conclude that a section through test holes
1 and 2 shows this portion of the pond was constructed using the
' downstream method of tailings pond construction. This means that
sands will underlie most of the clay material, with the clay
increasing in depth toward the decant tube. Test holes 3 and 4

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