2020-03-16_INSPECTION - M1974069

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14.2.1 Depletions caused by the gross evaporation from the Gravel Pits were estimated using the gross lake evaporation rates obtained from the National Oceanic and Atmospheric Administration Evaporation Atlas (NOAA Technical Report NWS 33), which averages 3.15 acre-feet per acre per year. 14.2.2 Historic natural depletions occurred due to consumption by preexisting natural vegetative cover on the land which is now, or will be, permanently replaced by an open water surface at the Gravel Pits. The historic natural depletions associated with the lands covered by irrigated crops is equal to the effective precipitation for irrigated land, which is equal to 70% of total precipitation. The historic natural depletions associated with the lands covered by phreatophytes (cottonwoods)was calculated using the Blaney- Criddle analysis with growth stage coefficients obtained from USGS Professional Paper 600-D, assuming an average depth to water table of five feet, and medium density growth. The historic natural depletions associated with such lands historically covered by shallow rooted (non-phreatophytic) non-irrigated vegetation is equal to the effective precipitation for non-irrigated land, which is equal to 90% of total precipitation. For the lands at the Larimer Pits to be mined subsequent to entry of this decree, the historic natural depletion associated with those lands shall be equal to 70043 of total precipitation. 14.3 Larimer Pits Net Evaporation: All ground water exposed to the atmosphere from mining operations at the ponds which will require replacement at the Larimer Pits site as shown on Exhibit A and B pursuant to the augmentation plan decreed herein occurred subsequent to December 31, 1980. Mining operations are ongoing at the Larimer Pits. 14.3.1 Up to 52.29 acres of ground water surface area were, or will be, exposed to the atmosphere by mining the Larimer Pits 13, 14, 15, 18 and 20 resulting in net evaporation averaging 109.24 acre-feet per year(gross evaporation less historic natural depletions)as shown on Exhibit C. Pits 2, 7, 8, 10, and 12 at the Larimer Pits were completed by December 31, 1980 and therefore the evaporative depletions from exposed ground water at those pits do not require augmentation pursuant to C.R.S. § 37-90- 137(11)(b). Case No. W-7412 continues to govern the augmentation and use of pits 1, 3, 4, 5, 6, 9 and 11 at the Larimer Pits. Larimer Pits 16 and 17 (aka Loveland Ready Mix Ponds 1 and 2 as described in Paragraph 16.2 below) do not require augmentation as these pits are lined. Larimer Pit 19 has been backfilled and does not require augmentation. 14.4 Baer Pit Net Evaporation: All ground water exposed to the atmosphere from mining operations in the Baer Pit occurred subsequent to December 31, 1980. Mining operations are complete at the Baer Pit. 14.4.1 17.2 acres of ground water surface area were exposed to the atmosphere by mining the Baer Pit resulting in net evaporation averaging 36.44 acre feet per year (gross evaporation less historic natural depletions) as shown on Exhibit D. 6 of 14