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002iL 4 steady flow (20k cfs, for example) was not evaluated beyond the patterns associated with the current operations since February 1997. The process associated with the matrix and accompanying supporting citations involved contacting researchers that had been directly involved with the 1996 BHBF (attachment a) as well as researchers recommended by program managers. Because funds limited the ability to bring researchers together for a workshop and the time of year also limited people's ability to participate, we decided to compile researcher opinions via fax and mail. A mailing was sent out in November 13, 1997 and researchers were asked to reply by December 3, 1997. Comments from scientists were received and scores for the matrix were averaged and provided to the TWO in their December 1997 meeting with a review provided by Barry Oold. The scientists rated effects to resources in a range from -3 (negative) to +3 (positive). The TWO recommended that that matrix be sent out again to the researchers for review and evaluation with a revised matrix availablel:?Y.!.lI!1u~l~Ll ~~8 to TWO and AM\\:'O. It \V~_ c1iscusse.c!,thata '-'meetingof the- scientistS providing information might be required to fully describe potential effects on resources. The matrix was sent out again prior to winter holidays with a request that evaluations be returned by January 9, 1998. Revised scores and comments were incorporated into the matrix and accompanying text. Included in the text were concerns voiced by researchers that pertain to resources such as sediment, the aquatic food base, Kanab ambersnail, and vegetation. The revised matrix, comments, notes and a summary of details were provided to the TWG in the January meeting by Barbara Ralston. Barbara explained how the values for the resources were obtained--via average scores and provided comments to the TWO member from the researchers regaroing specific resources. Among the comments by the researchers was vagueness of the scale associated with the matrix and a desire by the researchers to have an idea of what the anticipated flow volumes following a high flow event might be. The TWO and OCMRC agreed that researchers should be gathered to discuss the scale and to further develop the assumptions associated with the matrix. Researchers in areas that had negative impacts (-lor greater) associated with the resource were requested to come to OCMRC to discuss the rating scale and to clarify the assumptions. Prior to the meeting, the researchers were provided the previous matrices and text as well as a copy of the hydrologic trigger document, "BHBF Triggering Criteria" developed by the TWO Spike Flow Subgroup. Three groups of researchers were convened: sediment, aquatic biology, and terrestrial biology. In these discussions, the following assumptions were developed for the resources. Assumptions . A high flow would occur in the event that hydrologic triggering criteria were met. . A high flow would likely only be triggered in high water years so that flows preceding and flows following a BHBF would be high (e.g., 20-25,000 cfs). Directions to Developers of the Resource Matrix . The primary intent of the BHBF is sediment conservation with no harm to other resources. In effect, if sediment criteria are not met, then it is unlikely that a