2021-06-01_HYDROLOGY - M1977436

• Permit No: M1977436
• IBM Index Class Name: Hydrology
• Doc Date: 6/1/2021
• Doc Name: Substitute Water Supply Plan
• From: DWR
• To: DRMS
• Email Name: ECS
• Media Type: D
• Archive: No

Aggregate Industries South Platte Combined SWSP June 1, 2021
Plan IDs 3614, 4773, 3624, 4772, 4616, 3437, 3376, 3650, 3668, 5475, 5829, 8t 6090 Page 6 of 23
Depletions
The lagged depletions resulting from evaporation, water lost in mined product, dust control,
concrete batching, and dewatering operations at each site are shown in Table C below:
Table C - Depletion Summary (all amounts in acre-feet)
Lagged
Water Lost in Dust Concrete Lagged Dewatering Total
Site Name Evaporation Mined Product Control Batching Total Depletions Depletions Lagged
Impacting Depletions
the River
Jeronimus Pit 15.00 0 0 0 15.00 15.66 0 15.66
Hazeltine Pit 0 0 0 0 0 1.69 47.33' 49.02
Brighton Pit 2.73 0 0 0 2.73 5.48 2.17b 7.65
Tucson South Pit 27.35 10.60 0.51 0 38.45 33.58 0` 33.58
(360,000 tons
Wattenberg Pit 108.38 0 1.98 0 110.36 93.31 0` 93.31
Platte Valley Pit 169.15 13.15 19.07 8.37 209.74 214.14 0 214.14
(893,638 tons
Distel Pit Oa 0 1.54 0 1.54 1.54 0.011, 1.55
Tull Pit 10.32 18.13 0.99 0 29.44 22.65 0` 22.65
(616,153 tons)
Irwin-Thomas Pit 6.43 3.36 0.74 0 9.28 4.54 0` 4.54
(114,286 tons
Fredstrom Pit 0 0 0 0 0 1.23 0` 1.23
W.W. Farms Pit 178.56 14.56 0.99 0 194.11 189.51 O` 189.51
(494,648 tons
F-Street Pit 71.79 0 0 0 71.79 71.79 0 71.79
Total I I 1 - 682.44 704.63
'Evaporation is replaced by the City of Longmont under their augmentation plan decreed in water court case no. 09CW271.
b Lagged Dewatering Depletions, as shown in the table, are from past dewatering operations that have ceased but continue
to impact the stream system.
So long as the pit is continuously dewatered, the water returned to the stream system is considered to be adequate to
offset depletions attributable to the dewatering.
A stream depletion model using either the Glover method, or Stream Depletion Factor (SDF)
method (for the Brighton Pit) was used to calculate the lagged depletions to the river. The Glover
method uses four aquifer input parameters for each site as follows: 1) X - distance (ft) from centroid
of exposed groundwater to river, 2) W - distance (ft) from the aquifer boundary through the well to
the river channel, 3) T - transmissivity of the alluvial aquifer (in gallons per day per foot) between
the well and the river, and 4) S - specific yield (0.2 was used for all wells). The parameters used in
the model for each site are listed in Table D below.