|
S12f6S Wis Executive Branch Mail - Colovvyo RN -06 Cost Estimate Questions
<br />Tate
<br />Of
<br />„ lo�f d
<br />Colowyo RN -06 Cost Estimate Questions
<br />Stark - DNR, Jim <jim.stark @state.co.us> Wed, Dec 19, 2012 at 11:44 AM
<br />To: "Tennyson, Tony (Colowyo)" <tennyson @tristategt.org>
<br />Cc: Rob Zuber - DNR <rob.zuber @state.co.us >, Alysha Hernandez - DNR <alysha.hernandez @state.co.us >, Mary
<br />Rodriguez - DNR <mary.rodriguez @state.co.us>
<br />Tony,
<br />am working on the cost estimate for Colowyo's RN -06 and I have several volume question for the worst -case
<br />disturbance. As I attempt to put together the cost estimate, these volume numbers are extremely important, as
<br />they account for the vast majority of the mine's liability costs.
<br />1. You provided a "Table 1 - Summary of 2017 Bond Volumes" with the renewal materials. The volume listed for
<br />the Eastern and Western stockpiles (South Taylor stockpiles) is 52,822,000 CY. Based on the changes to these
<br />stockpiles in TR -81 (South Taylor /Lower Wilson - Rule 4, page 20), there is a total temporary volume of
<br />approximately 43,700,000 CY and a permanent volume of approximately 47,400,000 CY. This gives a total
<br />stockpile volume of approximately 91,000,000 CY. These numbers differ significantly from those shown in "Table
<br />V (both the temporary volumes and the permanent volumes). What is the correct volume of out -of -pit spoil for
<br />each of the temporary stockpiles. If the stockpile volume numbers differ from those listed in the permit, a revision
<br />will need to be submitted to update these numbers. Further, since these volumes are for a constructed fill,
<br />stability analyses and construction plans will need to be provided as well.
<br />2. In the "Table V you provide a volume for "Area 1", which is the facilities area, the West Pit and the Roads, of
<br />approximately 10,300,000 CY. Based on the TR -81 cost estimate, there was a West pit reclamation volume of
<br />approximately 13,100,000 CY (not including approximately 3,000,000 CY for highwall reduction), a facilities area
<br />volume of approximately 500,000 CY and a road volume of approximately 70,000 CY. This gives a total volume of
<br />approximately 13,700,000 CY. Since the West Pit was at a steady state when the estimate was calculated with
<br />TR -81, the TR -81 volumes should still be accurate. The volumes the Division believes are accurate are the
<br />numbers in the TR -81 estimate. These volume are approximately 3,400,000 CY more than what is given in "Table
<br />V. Do you know why there is a discrepancy in these numbers? Please remember that the Division can not give
<br />any "credit" for any backfilling and grading work that has been completed but not released in a Phase I Bond
<br />Release.
<br />3. There are no volumes listed for the East Pit in "Table 1 ". As I stated in question 2 above, credit for backfilling
<br />and grading can not be given until a Phase I Bond Release has been applied for and approved. Additionally, there
<br />is still backfilling and grading work that needs to be completed in the East Pit. The volume for the East Pit
<br />reclamation, from the TR -81 estimate, was approximately 1,300,000 CY. The Division believes that this volume is
<br />still accurate. This volume should be added to "Table V.
<br />4. The topsoil volume for the South Taylor area, included as part of the RN -06 responses in Table 2.09.9 -7 is
<br />approximately 1,650,000 CY (including future topsoil stripping operations). The volume used in the TR -81 cost
<br />estimate is approximately 2,300,000 CY (including future topsoil stripping operations). The total topsoil
<br />replacement at the Colowyo Mine was approximately 4,800,000 CY in the TR -81 cost estimate. This total
<br />volume closely matches the overall mine's topsoil balance in Table 2.05 -1 (also included in the RN -06
<br />responses), which is approximately 4,300,000 CY (the 500,000 CY difference may be accounted for in future
<br />topsoil stripping, which is not included in Table 2.05 -1). Based on these topsoil volumes, there appears to be a
<br />shortage of topsoil, as shown on Table 2.04.9 -7, in the South Taylor Pit area, of approximately 600,000 CY.
<br />Please review the topsoil available for replacement on the South Taylor Pit and the entire mine site and correct
<br />the above referenced tables as necessary. If you believe that the lower volume is correct, please provide a
<br />https: / /mail.google.com/ mail / ?ui= 2 &ik= 4546421a5a &vievu =pt& search = inbox &th= 13bb47b903a92f8b 1/2
<br />
|