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Builder’s Aggregate SWSP August 18, 2017 Page 4 of 7 The accretion reaches described in Paragraph 20.1 of Riverside’s decree in case no. 02CW86 are as follows: • River Reach No. 1: Riverside Inlet Ditch headgate to the Fort Morgan Canal headgate • River Reach No. 2: Fort Morgan Canal headgate to the Upper Platte and Beaver Canal headgate • River Reach No. 3: Upper Platte and Beaver Canal headgate to the Lower Platte and Beaver Canal headgate • River Reach No. 4: Lower Platte and Beaver Canal headgate to the North Sterling Canal headgate The Applicant’s depletions impact the South Platte River in Riverside’s Reach 3. Replacement supplies must be provided to Reach 3 or above the next downstream calling water right. As of the accounting filed for June of 2017, Riverside does not project any augmentation accretions from the available sources to Reach 3. In months where accretions to Reach 3 cannot be leased to BA and the call is such that replacement must be provided to Reach 3, Riverside will need to coordinate with the water commissioner in order to bypass supplies from Reach 2 to Reach 3 and will need to pay transit loss on those accretions. If the call is downstream of Reach 3, Riverside may have excess credits that can be applied within Reach 4 without a need to apply transit losses. Pre-1981 Exposed Area The Applicant described that a portion of the potential mined area was exposed to evaporation prior to 1981 and was naturally filled during flood events. The Applicant’s Figure 2 shows the pre- 1981 exposed area that is within the currently mining permit boundary. This area totals 0.76 acres, and it is not clear if any of this area is currently exposed to evaporation, since the stream channel has undergone a number of changes in recent years. Pursuant to Section 37-90-137(11)(b), C.R.S., a gravel pit operator does not need to replace depletions that occur due to evaporation from ground water exposed prior to January 1, 1981. BA is not claiming the pre-1981 area to offset any of the planned exposed groundwater during this SWSP approval period. In order to claim the pre-1981 exemption in future years, the Applicant will need to comply with the requirements described in the Guidelines for SWSPs for Sand and Gravel Pits, including providing a pre-1981 aerial photo, a topographical map showing the pre-1981 area, and a shapefile of the area. DWR does not allow pre1981 areas to be re-allocated to different locations within the permit boundary. Long-term Replacement In accordance with the letter dated April 30, 2010 (copy attached) from the Colorado Division of Reclamation, Mining, and Safety (“DRMS”), all sand and gravel mining operators must comply with the requirements of the Colorado Reclamation Act and the Mineral Rules and Regulations for the protection of water resources. The April 30, 2010 letter from DRMS requires that you provide information to DRMS to demonstrate you can replace long term injurious stream depletions that result from mining related exposure of ground water. The DRMS letter identifies four approaches to satisfy this requirement. As described in the SWSP request, BA plans to operate at the site for another 20 years and then plans to reclaim the area with a complete backfill of the exposed area. In accordance with approach no. 1, you have indicated that a bond has been obtained for