REV93955

• Permit No: C1980003
• IBM Index Class Name: Revision
• Doc Name: TABLE OF CONTENTS EXHIBIT VOLUME II
• Type & Sequence: MR13
• Media Type: D
• Archive: No

March 1998 Slrrmp Investigation and Mttigation Report ~ /'age 14
7.0 RECOMMENDATIONS
As described in the previous section, installation of permanent surface and subsurface drains
and grading modifications to promote positive drainage are the recommended nex[ steps for
this site. The specific recommendations and purposes are listed below, and the locations of the
features are presented in Exhibit I-L.
ACTION PURPOSE 'I
Monitor each piezometer quarterly for the Evaluate hydrogeologic conditions in the vicinity
presence and depth of groundwater. of the slump.
Install upper French drain -depth greater than 12 Intercept subsurface water from the south and
feet; drain rock to 1 .5 feet bgs; length at 200 west, near the slump head scarp.
feet.
Install middle French drain -depth greater than 12 Intercept subsurface water that may enter from
feet; drain rock to 1.5 feet bgs; length at 170 the head scarp or mid-slump area, and to drain
feet. the main slum mass.
Install slot toe drains; 2 drains to 8 feet bgs; drain Allow drainage of trapped water from the toe of
rock to 1 .5 feet b s; length at 50 feet. the slump.
Perform surface regrading and shallow surface Minimize infiltration into the sliding mass and
ditches to approximately 1 foot bgs-10,000 ft' of direct water away from the area.
re radin and 500 linear feet of surface ditch.
Revegetate with the seed mixture approved for Soil surface stabilization.
ponds 001 and 002.
Install a perimeter fence around the slump. Prevent access by livestock or wildlife.
Install Inclinometers. Slump mass movement monitoring.
Montgomery Watso>t Americrss ' P.O. Box 774018 'Steamboat Springs, Colorado " 80477 (970J 879-6260
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