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Actual engineer's certifications that features of the fills were constructed as designed <br />generally were unavailable for review. We reviewed an engineer's certification for the <br />CRDA-2 permanent diversion at the mine office. It certified that the diversion meets <br />required capacity despite not being constructed as designed in the permit. Though <br />DMG and the permittee believe a certification exists for the underdrains in CRDA-1, we <br />couldn't find it. According to the permit, underdrains 1, 2, 2A and 3 were constructed in <br />1980. The permit describes their respective lengths as 350', 700', 580', and 380'. It <br />also notes that the underdrains were filled with riprap and covered with filter fabric as <br />shown in Detail D of Exhibit 20. Engineer's certifications of other critical construction <br />activities did not accompany information and reports that I reviewed. 1 noted, however, <br />that DMG verified compliance with approved depths of non-toxic, noncombustible <br />material cover on the refuse piles during inspections it conducted on June 29, 1994, <br />and June 8, 1995. DMG documented its verification of cover depths in the reports for <br />those inspections, which I reviewed. <br />also reviewed 20 reports of compaction test results that typically were submitted to <br />DMG with quarterly reports. Compaction results were available in reports of tests <br />conducted in 1986, 1989, and each year from 1990 through 1997 to date. Of 120 <br />samples tested (82 of which were from CRDA-2 and 38 of which were from CRDA-1 ), <br />results showed that all but 7 samples attained at least 90% relative compaction (of the <br />maximum dry density). Three sample locations that failed were located on CRDA-1 <br />and four were located on CRDA-2. Those seven locations were retested and all <br />achieved at least 90% relative compaction the second time. <br />According to OSM's records, the requirement at section 4.09.1(11)(c) that color <br />photographs be included with any certified report addressing underdrain systems and <br />their protective filters was proposed in its entirety on September 9, 1988, and was <br />approved by OSM effective December 11, 1989. Underdrain construction completed <br />prior to that approval date would not have to be recorded on color photographs <br />submitted with engineers reports. Only CRDA-1 was designed with underdrains at the <br />Roadside Portals mine. If completed when initially built in 1980, the underdrains' <br />construction prelates the requirement for photographs. <br />We reviewed results of piezometric monitoring at the mine office. Our review focused <br />on the static water levels in 100, 200, 300, and 400 series piezometers and in <br />piezometers number CRDA-01, 01 A, 02, and 03 in CRDA-1 as recorded for the first, <br />second, and third quarters of 1997. We also checked monitoring results of <br />piezometers CRDA-04, 05, and 06 in CRDA-2 for the same period. Static water levels <br />measured were below critical target depths. The third quarter 1997 water level in <br />piezometer 307 shown in the permittee's field notes as 26.46' exceeded the critical <br />target depth of 84.19'. Mr. Reschke explained that the measured level was the depth to <br />which the sensor could be lowered in the hole and wasn't the depth to water, noting <br />that the borehole for this piezometer is not straight. He asserted that piezometer 307 <br />5 <br />