HYDRO28685

• Permit No: M1989120
• IBM Index Class Name: Hydrology
• Doc Date: 10/23/2007
• Doc Name: Combined Replacement Plan
• From: OSE
• To: Applegate Group, Inc
• Permit Index Doc Type: DMG Sampling
• Media Type: D
• Archive: No

Kim Edwards Page 11
South Platte Combined Replacement Plan
October 23, 2007
(b) For fields not deep tilled or chemically treated to successfully kill alfalfa, records of
monthly monitoring of depth to groundwater at existing irrigation wells or existing or
new monitoring wells or piezometers within'/.-mile of each alfalfa or native grass
field must be maintained. Credits will be reduced according to the following table
when depth to groundwater is less than the depth assumed to provide no significant
contribution to alfalfa growth. Measurements taken at the start of each month will
determine the necessary reduction in credit to be applied during the following month.
The applicant may use another methodology upon review and approval by the State
Engineer and Division Engineer.
Depth to Ground
W
F Percent Reduction in CU Credit'
ater (
eet)
Native Grass
Alfalfa
1 85% 100%
2 50% 90%
3 30°h 75%
4 20% 50%
5 15% 35%
6 10°k 20%
7 5% 15%
8 0% 10°k
1. Adapted from EVAPOTRANSPIRATION AND AGRONOMIC RESPONSES IN
FORMERLY IRRIGATED MOUNTAIN MEADOWS, South Park, Colorado, March 1,
1990; Revised September 1, 1991
12. The replacement water, which is the subject of this plan cannot be sold or leased to any
other entity. As a condition of subsequent renewals of this substitute water supply plan, the
replacement water must be appurtenant to this site until a plan for augmentation is
obtained. A copy of this approval letter should be recorded with the county clerk and
recorder. All replacement water must be concurrent with depletions in quantity, timing, and
locations. The use of replacement water must be in compliance with all agreements with
the providers of replacement water.
13. Dewatering at the pits will produce delayed depletions to the stream system. As long as the
pit is continuously dewatered, the water returned to the stream system should be adequate
to offset the depletions caused by dewatering. However, once dewatering at the site
ceases, the delayed depletions must be addressed. At least three years prior to completion
of mining, a plan must be submitted that specifies how the post pumping dewatering
depletions will be replaced in time, place and amount.
14. Approval of this plan is for the purposes as stated herein. This office must first approve any
additional uses for which the water may be used.
15. The approval of this substitute water supply plan does not relieve the Applicant and/or
landowner of the requirement to obtain a Water Court decree approving a permanent plan
for augmentation or mitigation to ensure the permanent replacement of all depletions,
including long-term evaporation losses and lagged depletions after gravel mining operations
have ceased. If reclamation of the mine sites will produce a permanent water surface
exposing groundwater to evaporation, an application for a plan for augmentation must be
filed with the Division 1 Water Court at least three (3) years prior to the completion of mining
to include, but not be limited to, long-term evaporation losses and lagged depletions. If a
lined pond results after reclamation, replacement of lagged depletions shall continue until