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Dam must ~e free of frazil ice, as it will flow directly to the Foothills Treatment Plant." This factor was clearly recognized in the FES which stated, with respect to the low dam and upstream alternatives, "winter icing problems would cause this diversion structure to be operative for only seven months of the year and necessarily change the Foothills treatment plant operation strategy." (FES 8-13) The change in strategy, as noted at page 8-12 of the FES, would require the plant to be operated as a peaking rather than a ~ase load plant as it has been designed to operate. In response to questions posed at the USBR ~riefing on its official memorandum, officials of that agency, notwith- standing the opinions of their own experts, asserted that they disagreed with the FES and believed that year-round operation was feasible so that the use of small diversion structures could be feasible. Those same officials admitted, however, that they gave no consideration to the fact that the filter plant could not handle ice-laden water. The fact is, no competent utility engineer would attempt to make a filter plant accommodate ice conditions 1 instead, the universal industry practice is to design and locate filter plants so as to avoid ice in the water to be treated. A comprehensive description of the extraordinary pro~lems ice-laden water could cause in the Foothills Treatment Plant is contained in Exhibit 10, prepared by the noted water utility consulting engineering firm of CH2M Hill. If any Federal decision-maker doubts the validity of the conclusions stated by the USBR Ice Research Management Team in Exhibit 9, a perusal of Exhibit 10 should dispel those doubts in the mind of any reasonable individual. Apparently the USBR took the position that the frazil ice pro~lem was merely one of avoiding conditions which would plug up the diversion structures; representatives speaking for that agency at the briefing on their report, asserted that they could solve the "problem" by heating the trash rack and raising the crest of the originally designed diversion dam by fifteen feet. Such an incredibly shallow assessment of the pro~lem is shocking when made by one who is assumed to be a responsible public official. This is so ~ecause of the extraordinary nature of the problem which does exist and which cannot really ~e understood unless one has actually observed the conditions which occur in the Canyon. Because the ice problem is so poorly understood by those who are not regularly confronted with solving it, Denver employed the services of an internationally-famous snow and ice expert, Mr. Walter U. Garstka, to evaluate the problem from his vast experience and to report on it so that the Federal decision-makers might gain a clearer insight into the pro~lem. His report (Exhibit 11) and an addendum -12-