_INSPECTION - C1980005 ‎(9)‎

• Permit No: C1980005
• IBM Index Class Name: INSPECTION
• Doc Name: Inspection Report
• Inspection Date: 7/14/2009
• Email Name: DTM
• Media Type: D
• Archive: No

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III. COMMENTS-COMPLIANCE
Below are comments on the inspection. The comments include discussion of observations made during the
inspection. Comments also describe any enforcement actions taken during the inspection and the facts or
evidence supporting the enforcement action.
operator by construction of a"V" shaped TRM lined extension of the PM-10 channel, extending
approximately 45 feet up through the slope segment that had eroded (Photo Ws 468 and 469).
The regraded landfill terrain does not precisely conform to the grades depicted in approved
designs. Map Exhibit 13-2A shows Channel PM-10 extending up through the upper valley
almost to the drainage divide, and design Exhibit 7-20 indicates a grass lined "V" shaped
channel, 1.1' deep for Channel PM-10, with a 13.9% slope. In actuality, the PM-10 channel
extends only through the short lower reach of the graded landfill site, while the remainder of the
upper PM-10 drainage could be described as a moderately steep valley headwall slope at the
upper end near the drainage divide, a low gradient swale feature through the middle section, and
the short, steep, gully repair channel section at the lower end. Inclinometer field measurements
indicate a 16% slope through the steep upper segment near the divide, and a 21% slope through
the steep TRM channel segment at the lower end of the site (in both cases, approximately 6% to
8% steeper than design grade). The steep west facing valley sideslope was measured at 3 1% in a
typical location, which corresponds closely to slope grade indicated on Map Exhibit 13-2A.
Photo#465 is a view from the low gradient middle segment of the drainage looking up toward
the valley headwall slope and the drainage divide; Photo Ws 466 and 467 are views down
drainage from the headwall slope. Photo #470 is of the west facing side slope.
Despite the observed variations from approved designs, the regraded landfill area appears to be
stable and adequately blends into the adjacent terrain. Good to excellent first and second
growing season vegetation cover has been established in all areas, except the TRM channel
segment that was only recently installed. Minor rills were noted in some locations along the
slope in the upper reaches of the drainage, but initial (first growing season) vegetation
establishment is good and it is expected that vegetation cover will be sufficient by next growing
season to prevent further erosion. Based on observed performance of TRM lined channel
segments in similar locations, it is expected that the TRM section of PM-10 at the lower end of
the reclaimed landfill site will function well, and prevent recurrence of the gully erosion
observed in the location earlier in 2009. Channel capacity conforms to the approved PM-10
design. For the reasons described,based on site inspection the Division's preliminary
determination is that the reclaimed landfill site has been regraded to approximate original
contour, and qualifies for Phase 1 bond release.
Permanent Channel PM-12A
The final area included in the SL-4 bond release request is a narrow corridor that extends from
Road E-1 down-slope to the vicinity of the South Road, in the southern part of the permit area.
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