REV04444

• Permit No: C1981022
• IBM Index Class Name: Revision
• Doc Date: 9/8/2003
• Doc Name: Adequacy Responses
• From: Montgomery Watson Harza
• To: DMG
• Type & Sequence: TR43
• Media Type: D
• Archive: No

Oxbow Mining, 1 1 r'- Tirhnrrat Rcairi°n 7843
11 IVat Caa/Before Facility
ferbniral Adegnary C°mmnul Re. p°nnf
.September 5, 7003
Yage fi
The ore of keyway tuts to stabilize the fill was not noted in the application. Please include in the rert~ed derign report
the use of keyway tuk on slopes steeper than 36%.
Please have the stability analyser of Appendix C of the Environmental.Strateger Corporation rerti~ed by a registered
engineer.
Response: The ESC design report has been revised to include specifications for any required
keyways and coal refuse placement and compaction. As previously noted in the response to
Comment 17, appropriate certification is provided in this response package for the ESC design report.
Copies of the revised design information accompany these responses for replacement in the Mining
and Reclamation Plan document.
56) Please include in the application a certified derign, to the requirements of Rule 4.09.2(2), for the proposed
rubdrainage ryltem of the proposed II Wert Coal Refuse Facility. Please include this portion of the derign in the certified
derign report of the structure.
Res onse: A sepazate certified underdrain design report has been developed for inclusion in Exhibit
2.05-E4. Copies of this supplemental design information accompany these responses For replacement
in the Mining and Reclamation Plan document.
57J Please include in the certified derign report the rpeeiftratianr of Rule 4.09.2(3).
Response: The permit text and ESC design report have been reviewed and revised, as appropriate to
address the applicable regulatory requirements. Statements cross-referencing the relevant
requirements have been incorporated into both the permit text and the ESC design report. Copies of
the revised information accompany these responses for replacement in the Mining and Reclamation
Plan document.
58J Please modify the ftnirhed top surface of the proposed 77 Wert Caal Refuse Facility (Drawing 2.05-M1 Sheet 5 of
SJ into a mound or tent-like surface (presently a Ieve1 rutfaceJ that sheds frugeert a 3% grade) water to the perimeter
ditcher m lieu of over the outrlape of the fell ar per Rrr1e 4.09.2(5).
Response: The surface of the fmal bench (elevation 6,250') will be sloped at approximately 2-3
percent (o the west to drain to the permanent diversion ditch IIW-1. Maps 2.05-M1 (Sheet 5 of 5),
2.05-M4 (Sheet 5 of 5), and 2.05-M6 (Sheet 5 of 5) have been revised to reflect the drainage gradient.
Copies of the revised maps accompany these responses for. replacement in the Mining and
Reclamation Plan document.
59J Please include the drainage designs that demonstrate comp/ionic with the nyuirementr of Rule 4.09.2(7) in the II
lYlest Coal Refute Facility certified derign report.
Res onse: Please refer to previous response to Comment 52.