HYDRO23244

• Permit No: M1979191
• IBM Index Class Name: Hydrology
• Doc Date: 6/23/2006
• Doc Name: Approval Period
• From: Applegate Group Inc.
• To: OSE
• Permit Index Doc Type: Correspondence
• Media Type: D
• Archive: No

Mr. Richard Raines
June 22, 2006
The total depletions for the four sites are shown in the following table:
TABLE B -DEPLETIONS
Page 2
Evaporation Lost in Dust Total lagged New Permit
Site Name Losses Product Control
(ac-ft)
Required?
ac-ft ac-ft ac-ft
61.45
15.85 (for 22.13* Yes
Three Bells Pit the (800,000 tons 1.88* 94.29
additional 7 of material)
acres
12.8 (435,000 No
Kyger Pit 25.2 tons of 0.8 38.8 (53502-F
material) valid)
Port of Entry Pit 65.6 0 0 65.6 No
60890-F valid
Weizel Pit 135.1 0 0 135.11 Yes
Total 303.2 36.4 2.68 333.8
*Note: Mining at the Three Bells Pit site has started in February of 2006
It should be noted that the only consumptive use at the Port of Entry Pit and Weizel Pit
sites is the evaporation of exposed ground water. Mining is complete at the Weizel Pit site. Port
of Entry Pit site is currently undergoing reclamation. Lafarge West, Inc. filed for a plan for
augmentation for the Port of Entry Pit site in case no. 2004CW 111. Lafarge West, Inc. also filed
for a plan for augmentation for the Weizel Pit site in case no. 2002CW205. The Kyger Pit is an
active mining site and will continue to include evaporation, water retained in the product and
dust control. The mining operation at the Kyger Pit has continuously dewatered directly back to
the Cache la Poudre River since 2000. The estimated dewatering rate at the Kyger Pit site is
approximately 1,200 gallons per minute.
The Three Bells Pit has been a mining reserve. According to the information provided,
mining will start at the Three Bells Pit in February 2006 in an area of approximately 20 acres.
This site will be continuously dewatered at a rate of 1,200 gallons per minute. The dewatering
trench will be approximately 4,000 feet in length and approximately 5 feet in width. The
estimated exposed surface area in the dewatering trench is 0.5 acres and the collection area is
0.5 acres. The estimated size of the planned wash pond is approximately 6 acres. Thus the
total exposed area at the Three Bells Pit mining site will be 7 acres, which will be in addition to
the existing 24.4-acre unlined pond. The timing of the lagged depletions from the dewatering
operations was determined through a stream depletion model for the Three Bells Pit. The
model addresses the lagged depletions at the Kyger Pit, Port of Entry Pit and Weizel Pit by
accounting for the net accretion credits at the river that occur due to the dewatering operation at
the Three Bells Pit. These accretions are applied to this plan against depletions from the Kyger
Pit, Port of Entry Pit and Weizel Pits. The attached Table 7 summarizes the accretion credits
from dewatering at the Three Bells Pit.
The estimated production rate at the Three Bells Pit is approximately 800,000 tons of
mined material annually, which results in 23.6 acre-feet per year of water lost with the mined
product. The total annual consumptive use for dust control at the Three Bells Pit will be