2012-12-27_REPORT - M1980244 ‎(17)‎

• Permit No: M1980244
• IBM Index Class Name: REPORT
• Doc Date: 12/27/2012
• Doc Name: QA Mon. & Test Results, Ph. 5 Berm Mod.-Apend. E Specs.
• From: CC&V
• To: DRMS
• Email Name: TC1
• Media Type: D
• Archive: No

Section 02200
Earthworks
amee
E. The CONTRACTOR will be responsible for the safety of temporary construction slopes.
CONTRACTOR shall inspect all temporary and permanent open -cut excavations on a regular basis
for signs of instability. Should signs of instability be noted, CONTRACTOR shall immediately
undertake remedial measures and shall notify MANAGER immediately. Permanent cut slopes shall
be left in smooth, safe, and stable condition at the end of the workday.
F. CONTRACTOR shall final grade excavations within the valley leach facility to establish positive
drainage to the Pregnant Solution Storage Area. In no case will depressions or bowls be permitted in
the valley leach facility area.
G. CONTRACTOR shall conduct all excavation and shoring operations in compliance with applicable
MSHA, Colorado State and Federal government laws and regulations.
3.05 SUBGRADE:
A. The MANAGER and CERTIFYING ENGINEER will inspect and approve the exposed subgrade
prior to any fill or Soil Liner being placed. CQA Monitor will confirm that the surface of the
subgrade is smooth and free of debris, grade stakes, angular rocks, roots, branches, vegetation, mud,
ice, or frozen material. If the subgrade is determined to be frozen, using the criteria identified in Item
3.06.10 of Section 2200, the CONTRACTOR may either remove and replace the frozen subgrade or
wait until subsequent temperature monitoring indicates the fill is unfrozen, at no cost to CC &V. The
subgrade shall have no sudden sharp or abrupt changes in grade.
B. CONTRACTOR is responsible for maintaining subgrades in a condition satisfactory to
CERTIFYING ENGINEER. CONTRACTOR shall protect prepared subgrades, including
previously approved subgrade, from weather, construction equipment, or other factors as outlined in
Part 3.06 of the SPECIFICATIONS. Subgrade surfaces, including previously approved subgrade,
that become softened or otherwise unsuitable for placement of fill, shall be repaired to
CERTIFYING ENGINEER's and MANAGER's satisfaction, at no cost to CC &V.
C. Prior to placement of fill materials, CONTRACTOR shall scarify all in -situ materials to a depth of 6-
inches, moisture condition, and recompact the subgrade. Compactive effort shall be adequate to
obtain a minimum of 95 percent of maximum dry density as determined by the standard Proctor test
(ASTM D698) for the particular fill material. Moisture conditioning shall be adequate to achieve a
uniform moisture and density. In rock areas, the CONTRACTOR shall prepare the subgrade by
removing loose rock fragments until competent foundation material is encountered as approved by
CERTIFYING ENGINEER.
D. If the underlying material is unsuitable to permit proper compaction of the subgrade,
CONTRACTOR shall loosen, aerate (or excavate and remove), and recompact the subgrade until the
top layer can be compacted as required. The recompacted surface shall then be scarified, as needed,
to provide a good bond between the foundation and fill materials.
3.06 FILL PLACEMENT:
A. The following general guidelines shall be followed except as noted elsewhere in this Section.
1. No fill materials shall be placed until the foundation and subgrade preparations have been
completed as specified herein, in Article 3.05 of this Section. The procedures for fill
placement shall be approved by MANAGER and CERTIFYING ENGINEER prior to
start of fill placement.
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