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DBMS Comment 2) - Piezometer Data - The GMR cover letter (page 2) states that
<br />"Piezometers inside the slide area tend to have higher psi readings than those outside
<br />the slide area." The data presented for 07-GI3 (inside the slide) are indeed higher than
<br />the measurements reported for 07-GX5 (outside the slide), but the pore pressure
<br />readings for 07-GI10 (also inside) are more similar to 07-GX5 than they are to 07-GI3.
<br />Please reconsider the statement referenced above and rephrase if necessary. The
<br />comment was merely an observation that is generally true. While the values for the
<br />deepest zone, Q seam, are similar for GI10 (inside the slide) and GX5 (outside the slide),
<br />the values in the middle zone are noticeably higher in GI10 than they are in GX5. I
<br />would prefer to leave the March 2008 cover letter as is; however, in the future I will
<br />refrain from making observations that may not add a lot of value to the report.
<br />DRMS Comment 3) - Piezometer Data - page 2 of the GMR cover letter states
<br />"Readings from the Z pit piezometer indicate insignificant amounts of pore pressure.
<br />This piezometer was inadvertently destroyed in September and is currently inactive."
<br />The Piezometer Data spreadsheet reports zero value for pore pressures in the Z pit
<br />piezometer (07-ZI2) prior to the date at which it was destroyed. Please provide the data
<br />(if any) that were collected for 07-ZI2 prior to the time the piezometer was destroyed.
<br />This piezometer was monitored in June, July and August of 2007. In June there was no
<br />pore pressure (the hole was dry as expected). In July there was a low reading of 0.09 psi
<br />in the deepest zone. In August, there was no pressure again. The zeroes that you see on
<br />the report are the readings for this piezometer.
<br />DRMS Comment 4) - Bench Marks - Page 3-27a describes the planned construction of
<br />19 holes, of which three (3) will be fitted with inclinometers and four (4) with
<br />piezometers. In addition, page 3-27a states, "all the sites will have surface benchmarks."
<br />The March 2008 GMR indicates that all 19 holes were drilled between late February
<br />and late July of 2007. Inclinometers and piezometers were installed as planned;
<br />however the actual number of benchmarks established is only nine (9) rather than the
<br />19 described in the permit. The number of surface bench marks installed is less than
<br />half the number that was committed ton (9 versus 19) in TR-99. Please explain to the
<br />Division both the reasoning behind and proposed justification for this variance.
<br />Trapper generally has not established benchmarks at sites where other instrumentation
<br />exists (GI2, GI3, GX5, GX6, ZIl, ZI2). Instead, Trapper has been monitoring additional
<br />sites as described below:
<br />Type
<br />Reflector
<br />Reflector
<br />Reflector
<br />Reflector
<br />Sign
<br />GI4 post
<br />Post
<br />Post
<br />05-Gl-CCR
<br />Location
<br />404,637N, 1,436,583E
<br />403,950N, 1,436,703E
<br />404,130N, 1,437,107E
<br />403,350N, 1,437,980E
<br />401,123N, 1,437,149E
<br />402,202N, 1,437,957E
<br />402,909N, 1,435,619E
<br />402,217N, 1,436,307E
<br />403,209N, 1,437,588E
<br />Multiple readings have been taken at these sites as is evidenced by the attached tables.
<br />Locations of these sites are shown on the attached photo (highlighted in green). When
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