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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 />and maintenance response procedures employed by the City of Palisade, and the pipeline corridors were
<br />monitored on a regular basis during the period of mining. Subsidence impacts to the pipeline were not detected
<br />by the permittee during the period of mining, and have not been reported by the City of Palisade. The City of
<br />Palisade was notified of the bond release application and the bond release inspection, and did not comment on
<br />the application or participate in the inspection.
<br />Map Exhibit 46 (Man Made Features Map) depicts a power line (Xcel Transmission Line to Palisade Water
<br />Control Station) which closely parallels the Palisade Water Line along Cottonwood Creek. The powerline was
<br />not observed during the inspection, and subsequent investigation has revealed that the transmission line was
<br />removed during the 1990's.
<br />Hydrologic Features-South Portals Area
<br />Two intermittent streams, Rapid Creek and its major tributary Cottonwood Creek, were undermined by South
<br />Portals workings, and undermined segments of both streams were included in the liability release request area.
<br />Both streams are intermittent during most years, but flow continuously during wet years. Reservoir diversions
<br />and releases higher in the watersheds of both streams affect flow levels and seasonal duration of flows through
<br />the permit area. Possible subsidence related dewatering of the streams and associated alluvial aquifers was a
<br />concern during initial mine permitting, and surface flows and alluvial water levels have been monitored since
<br />1985. Pedestrian surveys were also conducted to document subsidence effects during the period of mining.
<br />Protective coal pillars were left in place beneath the streams to minimize potential subsidence effects.
<br />Monitoring indicated the presence of minor surface cracking and minor ponding of short duration along affected
<br />stream segments after undermining. The cracks and ponding persisted for a year or less, as the cracks and
<br />depressions filled in with sediment during the next high flow period. Monitoring of stream flow and alluvial water
<br />levels has not detected any significant water loss due to subsidence.
<br />During the bond release inspection on August 28, an upper segment of Cottonwood Creek in the NE'/a Section
<br />12, downstream from Surface Water Gaging Station (SWGS) 02, was viewed, by slowly walking along the road
<br />above the stream (dense brush along the streambank prevented walking closer to the stream). There was a
<br />modest flow in the stream (flow depth in the SWGS 02 flume was 4.2"). No cracking, ponding, or other possible
<br />subsidence features were observed. This segment of the creek had been undermined, and was included in the
<br />liability release area.
<br />An upper segment of Rapid Creek downstream of SWGS 03, in Section 6, was also inspected on August 28, in
<br />similar fashion. There was also a small flow in Rapid Creek (flow depth in the SWGS 03 flume was 1.5"). As
<br />with the upper segment of Cottonwood Creek, no cracking, ponding, or other possible subsidence features were
<br />observed. Detailed inspection was challenging due to dense riparian vegetation along the stream, similar to the
<br />segment of Cottonwood Creek described above. This segment of Rapid Creek had been undermined, and was
<br />included in the liability release area.
<br />A short lower segment of Cottonwood Creek immediately upstream of the Rapid Creek Confluence
<br />(approximately 300 feet), and a segment of Rapid Creek (extending from approximately 600 feet upstream of the
<br />confluence to 800 feet downstream of the confluence) in Section 1, were also undermined. These stream
<br />segments were not inspected during the initial inspection on August 28, but were inspected during afollow-up
<br />inspection on October 17. Both streams above the confluence and Rapid Creek below the confluence are
<br />stable, relatively high gradient, low sinuosity, "B" type channels, with basalt boulder/cobble substrate, within
<br />steep sided valleys. Channel banks support a narrow riparian zone, thickly wooded with shrubs, vines and small
<br />trees, including willow, dogwood, narrow leaf cottonwood, Russian olive, woods rose, skunkbush, and poison ivy.
<br />Upland vegetation in the confluence vicinity is pinyon-juniper woodland. The combination of steep slopes, thick
<br />brush, and large boulders, made travel along the channels difficult in most areas, but each of the segments
<br />above the underground workings was walked to check for evidence of subsidence. Both channels carried some
<br />flow; Cottonwood Creek flow was higher than Rapid Creek above the confluence, but both channels could be
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