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Exhibit A-2 CT2015-73 (C154219) Statement of Work Rio Grande Cooperative Project (Amended August 2015) BACKGROUND The San Luis Valley Irrigation District(SLVID)owns and operates the Rio Grande Dam and Reservoir on the Rio Grande in southwest Colorado.The dam is a 111-foot high earth and rock fill embankment with a crest elevation of 9470 feet. Key features of the project include the dam with a crest length of approximately 450 feet,an un-gated spillway at the right abutment of the dam, and a low level outlet that includes an 11-foot high by 15-foot wide tunnel with a multiple sluice gate control structure near the middle of the tunnel. The reservoir is approximately six miles in length and 0.50 miles in width, oriented in a roughly northwest-southeast direction and has a capacity of 52,192 acre-feet. A comprehensive study for rehabilitation and/or enlargement of the dam and reservoir was conducted by D&A and CDM in 2007 and 2008 ("Rio Grande Multi-Use Rehabilitation and Enlargement Study, " CDM, 2008). That study estimated costs of$19.2 million for rehabilitation and $33.2 million for enlargement. In addition, the District has previously conducted studies regarding operations of Rio Grande Reservoir. The Rio Grande Reservoir Multi-Use Project Studies(collectively "Multi-Use Studies") identified basin-wide benefits from the use of storage and re-operations of Rio Grande Reservoir.These studies also concluded that CPW can particularly benefit from storage in Rio Grande Reservoir as it relies upon storage to manage some of its water resources. In recent years, under a non- permanent lease agreement, CPW, the San Luis Valley Water Conservancy District and others have stored up to 10,000 AF of water in Rio Grande Reservoir. In addition,the benefits of compact storage for Rio Grande Compact compliance and basin administration were outlined. The Multi-Use Studies revealed that Rio Grande Reservoir must be rehabilitated in order to provide long-term regulation of CPW water rights and other basin water supplies as well as storage for compact compliance. Construction of the dam began around 1908 with completion in 1914.The dam was constructed in a narrow valley between a massive volcanic formation known as Fish Canyon Tuff(at the right abutment) and a large rock slide that is a mixture of clays, sands, gravels, and large blocks of tuff(at the left abutment). The highly permeable rock slide material at the left abutment has been problematic since the first filling of the reservoir where seepage of the order of 1,500 gpm has been measured in the left abutment, with a total combined seepage of 2,500 gpm downstream of the dam. The seepage flow is responsive to reservoir elevation with flows increasing significantly at higher reservoir elevations(at gage 60 and above). The dam was originally constructed with an unlined spillway at the right abutment. The spillway has been modified since its original construction by lengthening the crest of the spillway and lining the spillway deck and walls with concrete. A recent analysis on the spillway, performed by CDM in 2008, suggests that the spillway training walls are insufficient in height to pass the required 6,600 cfs design flow. The training wall height deficiencies exist at the entrance of the structure and continue throughout its length. The greatest concern with the spillway training wall heights exists on the left side. Any overflow of the left training walls has the potential to threaten the right abutment of the main dam. Based on the 2008 study,this appears at flows below the design flow of 6,600 cfs. The dam safety and operational issues described above combined with the value of the reservoir for optimizing water use for multiple stakeholders in the basin have driven the District to move forward with the rehabilitation of the Rio Grande Dam and Reservoir. The District is a proponent of the Rio Grande