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The table shows, not the active operating capacities but only the total storage capacities of the various alterna- tives and shows the high dam with,a 7700-acre foot capacity and the low dam with a 4300-acree foot capacity. The implica- tion is that the quantities stated represent the full, active regulatory capacities of the two structures. This is not true; the USBR, for some mysterious reason, chose not to compare the reservoir capacities in the way it normally makes such compari- sons for its own structures. That technique, described in excerpts from the USBR's own agency manual (Exhibit 16), would have broken down the increments of storage in both facilities and by doing so, have given a true picture of the drastic re- duction in the active operating capacity which would result from the selection of the low dam alternative. When asked at the briefing on the document what the operating capacity relationships were, the USBR officials did not know, because they didn't know how many acre feet of capacity was located above the outlet for the low dam. They could have discovered this by simply asking Denver for a copy of an area capacity table for the site (Exhibit 17). If they had done so, they would have discovered that the true relationship would have shown the high dam with 4400- acre feet of active regulatory capacity while the low dam would have only 950-acre feet of such capacity. Again, if they had sought the correct information, the statement appearing on page four of their document would have pointed out that the low dam would reduce the regulatory capacity by 79.5%, not the misleading said 62% reduction which appears in the memorandum. But, more important than the misleading description, is the fact that the 950-acre feet of active capacity pro- vided by the low structure is only slightly more than one- third of the absolute bare minimum of operating storage which good utility practice dictates must be provided for a project of this magnitude on a stream such as the South Platte River. (see Exhibit B) In view of those absolute minimum needs, the USBR comment that the reduction in capacity would produce "*** some minor reduction in future M & I water delivery ***" appears ludicrous. It is even more ludicrous in light of the statement by the agency's repre- sentatives at the briefing session that there had been no operating study made to find out just how much water would be lost nor how much operating capacity would be required for sound, safe operation. Surely no responsible decision-maker could conscien- tiously choose a structural alternative which doesn't even meet minimum requirements for reliable plant operation. But the loss of operating storage would not be the only disadvantage of a low dam. Both Garstka and Borland (Ex- hibits 11, 12 and 14) indicate serious reservations about -15-