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. . . The baseline is based on a 70R spill avoidance strategy (70R strategy). The 70R baseline strategy involves assuming a 70-percentile inflow into the system subtracting out the consumptive uses and syslem losses and checking the resuhs to see ifall of the water could be stored or ifflood control releases from Lake Mead would be required. If flood control releases from Lake Mead would be required, additional water is made available to the Lower Basin states beyond 7.5 maf. The notation 70R refers to the specific inflow where 70 percent of the historical natural runoff is less Ihan this value (17.4 mat) for the Colorado River basin at Lee Ferry. In praclice, the 70R surplus determination trigger elevation would be made during the fall of the preceding year using projected available system space. The 70R strategy trigger line gradually rises from approximately 1199 feet above mean sea level (ms!) in 2002 to 1205 feet msl in 2050 as a result of increasing water use in the Upper Basin. Under baseline conditKlns, when a surplus conditKln is determined to occur, surplus water woukJ be made avaihble to fill all water orders by holders of surplus waler contracts in the Lower Division states. Reclamation has utilized a 70R strategy for both planning purposes and studies of surplus determinations in past years. When Reclamalion reviewed previous surplus detemlinations as part of the Draft Environmental In~act Statement (OElS) effort, the data indicated that the 1997 swplus deternlination did not precisely fit the 70R strategy. As a result, Reclamation selected the 75R strategy as representative ofrecent operational decisions for use as the baseline condition in the OEIS. However, based on further review and analysis, public connn~'lt, and discussion with representatives of the Basin Slates during the DEIS review period, Reclamation selected the 70R strategy for the baseline condition in the FEIS. While the 70R strategy is used to represent baseline conditions, it does not represent a decision by Reclamation to utitize the 70R strategy for determination of future surplus conditions in the absence ofimerim surplus guidelines. It should be noted that the 70R strategy and 75 R strategy produced very similar modeling results for the pwpose of determining impacts associated with the action alternalives analyzed in this FEIS. The primary effect of simulating operation with the 70R strategy would be that surplus conditions would only be determined when Lake Mead is nearly full. 2. Basin States Alternative (Preferred Ahernative): The Basin States Alternatives is similar to, and based upon, information submitted to the Secretary by representatives of the Governors of the stales of Colorado, Wyoming, Utah, New Mexico, Arizona, Nevada and Calirornia. After receipt of tlus infornntion (during the public connnent period), Reclamati:lI1 shared the submission with the public (through the Federal Register and Reclarration's surplus guidelines web sites) for consideration and comment. Reclamation Ihen analyzed the states' submission and crafted this additional alternative for inclusion in the FEIS. Some of the inrormation submitted for the Department's review was oulside of the scope of the proposed action for adoption of interim surplus guidelines and was therefore not included as part of the Basin States Alternative (e.g., adoption ofshortage criteria and adoption ofsurplus criteria beyond the 15-year period) as presented in the FEIS. The Basin States Alternative specifies ranges of Lake Mead water surface elevations to be used through 2015 for determilung the availability of surplus water through 2016. The elevation 5