PERMFILE116538

• Permit No: C1981034
• IBM Index Class Name: Permit File
• Doc Date: 12/3/1979
• Section_Exhibit Name: APPENDIX A Fox Part 2
• Media Type: D
• Archive: No

i,
' gradation curve for the material should generally be parallel to that
of the relatively pervious strata as shown in Figure 8. These criteria
' may have to be revised if a more coarse grained material or more per-
vious strata is encountered during construction.
' The top of the filter material should be sealed against infiltration at
' the top of the relief wells. The perforated pipe should discharge away from
the embankment by gravity means. Refer to F igure 5 for a cross section through
a typical dam showing the proper design rec ommendations.
Based on the dam construction following the recommendations outlined
' above, we have calculated the stability for the structure utilizing all the
' criteria obtained during this investigation. For purposes of the stability
analysis, and because the foundation of the structure consists of a layered
' soil system, we conducted a "sliding wedge" analysis for failure of the down-
stream toe along the weak foundation layers. Our analysis shows that the
' dam constructed as outlined above will have a sufficient factor of safety
against a wedge type failure. Total settlement of the structure, as planned,
is expected to be minimal; however, some differential settlement may occur
' due to the offset design of the cutoff trench. The downstream slope, especi-
ally near the crest should be periodically inspected for signs of cracking
' due to settlement, and repaired if necessary.
COF2STRUCTION RECOh1F1EFlDATIOFlS
' 1. Prior to constructing the dams, the foundations should be properly pre-
pared by cleaning and grubbing all organic material within the areas of
' the foundations.
2. The positive cut off trenches should be excavated down to the top of
' the medium hard bedrock. Particular care and supervision should be
' utilized so that the bottom of the cut off trenches are founded below
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