REV103226

• Permit No: C1994082
• IBM Index Class Name: Revision
• Doc Date: 1/18/2002
• Doc Name: REVIEW OF PERMITTEES RESPONSES TO ADEQUACY LETTER OF DEC 28 2001 SENECA COAL CO THE YOAST MINE DMG
• From: DAN HERNANDEZ
• To: MIKE BOULAY
• Type & Sequence: MR16
• Media Type: D
• Archive: No

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STATE OF COLORADO
DIVISION OF MINERALS AND GEOLOGY
DeUarlmenl o! NaNral Resources
1313 Sherman SL, Room 215
Denver, Colorado ft0203
Phones (3031 P~66-3567
FAX: [phone] U6
DIVISION OF
MINERALS
GEOLOGY
RECLAMATION
MI NING•SAFETY
Date: January 18, 2002
Bill Owens
To: Mike Boulay Governor
Greg E. Walther

~ Executive OueUUr
From: Dan Hernandez
~'~ Michael B. Long
Dwis~on Duenor
Re: Review of Permittee's Responses to Adequacy Letter of
December 28. 2001, Seneca Coal Company, The Yoast Mine,
DMG Perini[ No. C-92-084, Minor Revision No. MR-16
As per your request. I have reviewed Seneca Coal Company's responses to our December 28, 2001
adequacy letter for this Minor Revision. The permittee's responses are dated January I5, 2002, and
were submitted to us on the same day.
Response to Adequacy Question #1
In the original MR-16 application, the permittee had provided calibration certificates for all
bu[ one of the seismographs used in the 11/29/01 ground attenuation study. DMG requested
[he calibration certificate for this remaining seismograph. The permittee provided the
certificate in the 1/15/02 response package. The certificate indicates the seismograph was
calibrated approximately nine months before the study, which is acceptable. I therefore
recommend the following comment to the pern3i[tee:
The Division is in receipt of the calibration certificate for seismograph
"BC5536". This instrument was calibrated approximately nine months before
the 11/29/01 study. This is acceptable. No further response is necessary.
2. Response [o Adequacy Question #2
In the original MR-16 application, values for Distance, Scaled Distance, and Peak Panicle
Velocity associated with seisrnograph "BE6516" from the third test blast were not provided
in the Appendix IV data table. In the January 15, 2002 response, [he permittee explained
that the ground motion trigger level for this seismograph had been set at 0.05 inches per
second, and that the ground motion from the third test blast at the seismograph was
apparently less than this, as the seismograph did not record any motion. The permittee
provided a revised Appendix IV data table to ret7ect this. The permit[ee's response is
acceptable. I therefore recorntnend the following comment to the permittee: