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I '. I I I I I II I I I I I I I I I I I I I Woodward.clyde Mr. Je1fBruggink u.s. Forest Services August 9, 1996 Page 2 Clearly, the are previously selected by the USFS on the attached map (Exlnbit A) meets all, if not most ot: these criteria The slopes on the east side of the County Road 126 are ofhighly erosive, decomposed granite and are without vegetative cove to prevent dislodgment and transport by rainfiill. Movement of sediment from these areas during significant rainfiill events has already been documented during the July storm. Many of the aIiverts beneath the road are currently plugged with sediment, exacerbating the flood and hazard condition along the road bed. Application of the BFM and subsequent vegetation estab1ishment will reduce the potential for erosion and sediment delivery downslope from these areas. SimiIarly, slopes on the west side of the road and adjacent to the creek have the potential to conlIibute significant sediment loads to the creek itself; bulking the flow above nonnallevels, imperi1ing downstream properties in BuffiIlo Creek and ~~g the water supply system a1ready damaged by the July stann events. Application of the BFM and eventual revegetation of these slopes, coupled with contour tree felling and roto-breaking in the upper watersheds, will reduce this area's contribution to the overall amount of sediment going into the creek. It is our Wlderstanding that the USFS estimate is for approximately 50 acres for BFM application. Although we did not have access to maps of sufficient scale to planimeter the area (and "wheeling" to establish size is, as you are aware, inappropriate) it is the consensus of the group that the actual area identified by the USFS is probably somewhat less than 50 acres, perhaps 40 to 45 acres. ApDlication. Timing and Logistics It is suggested that a pre-bid walk-tbrough of the bonded fiber matrix application areas be conducted with hydraulic seerl~ contractors who wish to bid on the work. It has been our experience that the amount of effort on the part of man and machine for post-fire remediation is - typically\1lldew.i;...lItPrl by contractors who are nnflmn1iarwith the special conditions this type.>f work entails. n,e application should be based on the specifications, supplied as Exhibit B, by a contractor trained and certified by the mamm."lurer of the BFM. The appropriate seed mixture should include a sterile ammal and should be applied hydraulically as a first step before the complete application of the BFM. This is to ensure contact of the seed with the ground. Application should be by hose to ensure 100"10 ground coverage, unless safety and access preclude their use: For example, slopes directly above the road on the east side of County Road 126 can probably be more efficiently and safely treated from the turret or cannon of a hydraulic seeder. 2 INlATAlIUFALOllOC _lAM)