REV99304

• Permit No: C1982057
• IBM Index Class Name: Revision
• Doc Date: 9/1/2004
• Doc Name: 2nd Adequacy Review Letter
• From: Seneca Coal Company
• To: DMG
• Type & Sequence: PR4
• Media Type: D
• Archive: No

Daniel Mol/iemr
Diviriau of Minerolr and Geolag)~
SeplemGer t, 2004
Page 4
•
2.06.9 A~e~ne
8. Item Resolved
9. Item Resolved
10. Item Resolved
11. Item Resolved
12. Item Resolved
13. This item requested certain Tab 79 narrative madifitationr related to barkfilling and grading xhedule. In general,
the revised narrative is aaeptable, however we have one substantive reguert, and we note one typographical error
The typo8raphica! error is that there are taro amended pager designated `3a'; the 2°^ should be `36". The
rabrtantive request pertains to the 'Redamation Scheduling" table on page 6. The 'Tina! Grading" action r fern
to Exhibit 79-1 for pertinent rchedule, and rhould in addition refer to Exhibit 19-1f7. In addition, a major
reclamation activity `permanent drainage channel reconstruction" Is not addressed in the table. It it not clear
whether channel constsuaion including nprap installation it considered a component of final grading to be
completed in accordance with Exhibit 19-1 dr lA rchedule, or whether an additional timeframe is assumed to
allow for final drainage construction within a final graded area. Please amend the narrative sections of
Tab 19 to correct page numbering and c/arify rimeframe for drainage chorine/:
construction. Permanent cham:el construction including tiptop installation should be
• completed within one year of completion ofrnal grading ofadjacent backlit/ s/apes, and
prior to topsoiling ofareas adjacent to the channel.
Response: The 2"d amended page "Sa" has been corrected to designate page "56".
The Reclamation Scheduling table (page 6) has been updated to include reference to the timing
of construction of permanent post mine channels.
14. Item Resolved
1 S. Item Resolved
16. Item Resolved
17. Item Resolved
2.05.30 Ponds. ImDoundmentt. other treatment jacilitier and diverrionr
18. The Division had requested a revised stability analysis jot Pond 017, due to apparent disvepancy between dry
density valuer recorded for comported embankment materials and dry densltier used in the stability analyrir.
Operator's response it that the stability analyrir density value war a mairt density, not a dry density, and that
corrrpaction test results could be adjusted to derive the moist density value used in the stability ana)~sir.
This it not a satisfactory rerponre. Standard engineering practice is to compare design dry density to quality
control dry density tests. Design dry density is deternrined by tenting with a range of moisture rontentr, with
appropriate compaction art, are prescribed. The ana~~sir should, without interpretation by the Division,