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INSPEC42302
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INSPEC42302
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Last modified
8/24/2016 9:45:56 PM
Creation date
11/18/2007 11:25:50 AM
Metadata
Fields
Template:
DRMS Permit Index
Permit No
C1981041
IBM Index Class Name
Inspection
Doc Date
9/28/2001
Doc Name
COAL INSPECTION REPORT
Inspection Date
8/14/2001
Media Type
D
Archive
No
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III. COMMENTS -COMPLIANCE <br />Below are comments on the inspection. The comments include discussion of observations made <br />during the inspection. Comments also describe any enforcement actions taken during the inspection <br />and the facts or evidence supporting the enforcement action. <br />(6) Blending ofregraded land to undisturbed areas--- <br />(7) The functioning of reconstructed drainages with regard to knickpoints, blending at disturbance <br />boundaries and channel erosion--- <br />(8) Erosional features--- <br />Items (I) through (8) were evaluated for each of the areas wherebackfilling and grading had been <br />completed, and observations pertinent to these factors for the various final graded areas are addressed here <br />below. <br />North Decline <br />The North Decline map as amended in the revised bond release application accurately depicts the area of <br />completed backfilling and grading, with certain areas to be excluded from the bond release request. The <br />areas delineated on the map as being subject to further work, and thus excluded from the bond release <br />request properly include the east and west SAE sumps, Sediment Pond 7, and a small area to be used for <br />stockpiling of soil from the mine de-watering drilling project approved in TR-33. <br />Settling of the portal decline fill in the vicinity of the lower segment of the permanent channel has resulted <br />in a lowering of the original contours, and creation of a shallow depression in the channel which pools <br />water when the channel flows. Over time, the depression will fill in with sediment, but in the interim the <br />settlement has resulted in the creation of a small wetland area, with no evident negative ramifications to <br />channel stability. Permit Exhibit 21 specifies a steep channel segment (7.5%) and a low gradient channel <br />segment (2.5%) with design parameters for each segment. The original channel construction was certified <br />by Larry Reschke of PCC, in 1995, and a segment reconstructed in 2000 in association with Ute Water <br />Line installation, was certified by Jim Stover in July, 2001. Representative channel bottom widths of 35' <br />and 38' were measured during the bond release inspection, with representative depths of 34", 36" and 38" <br />(including berm height), and 22" and 27" (not includingberm height). Required bottom width is 35', with <br />depth of 24". The low gradient channel segment of the Ute Water reconstruction reach was estimated using <br />an abney level to be approximately 5%. ]im Stover's surveyed grade for the segment was 3.2%. Given the <br />relative precision to be expected with an abney, the surveyed grade is considered reasonable. This <br />compares to design gradient of 2.5%. In his certification, Mr. Stover included a table relating flow depth to <br />velocity, showing that [he design ramifications of the discrepancy between the design specification and the <br />surveyed gradient were insignificant. The high gradient segment of the channel, immediately downstream <br />from the Ute Water reconstruction reach, was estimated with theabney level to be approximately 8%, <br />which is comparable to the design specification of 7.5%. The channel has functioned well since original <br />construction in 1992, with no significant erosion and no instances of storm flow escaping the channel. <br />During the field inspection on August 15, it could not be discerned from visual observation whether the <br />upper segment of the North Decline permanent channel would meet design depth requirement of 24", <br />
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