APPCOR10885

• Permit No: C1981034
• IBM Index Class Name: Application Correspondence
• Doc Date: 4/2/1980
• Doc Name: RED CANYON #1 MINE FILE #77-232
• From: MLR
• To: GRAND MESA COAL CO
• Media Type: D
• Archive: No

N
Mr. Larry Reschke
April 2, 1980
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8. On page 86 of Design of Small Dams, the text states "The inflow
design flood most critical- .. sTwuld be used for final design.
Often it is necessary. to route floods fran both thunderstorm
rainfall and general storm rainfall to determine which flood
type is critical." As thunderstorm rainfall will yield a higher
cfs in this waterbed, it should be routed.
9. In sizing ditches, using a peak runoff/acre figure derived fry
total peak flow divided by total area assumes uniform slope,
land conditions, and other factors, so disturbed and undisturbed
areas should be conputed separately, or the SCS or rational formula
used.
"Coumazts on Surface Water Monitoring:
Please clarify that any discharge from the mine area will be
•monitored per the NPDES standards.
2. The irrigation water flowing over the property fran the north,
if sufficient to cause discharge of itself (keeping storage volume
for the 10 year event open in the pond), should be monitored above
and below the mine disturbance. Applicant should suggest a
schedule and parameters, probably including those critical to
agriculture (Baron, Chlorine, Selenium, Sodium Absorption Ratio).
Enclosed is amain concerning design and construction requirgnaits for Reten-
tion Dam ~~1.
Exhibit E Rec]"amation Plan
Cartnents on approximate original contour and subsidence problems will
follow when reviewed by technical staff.
Will regrading be done along the cauntour? (717.14 (F))
On page D-11 of the permit application submitted January 11, 1980, it
is mentioned that an MSHA refuse permit area was filled and compazted.
Will this be included in general reclamation?
It is mentioned an page E-1 of the permit application that topsoil berms
will be used on recontoured slopes. Are these to be permanent? Why would
they be used?