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L~ <br /> <br />12/20/79 Memo, p. 3, #1 <br />Road Drainage <br /> <br />"1. Page 816-194. Peak flow estimate for road culverts <br />assumes that runoff is decreased from reclaimed areas. <br />Calculations should be redone using a higher curve <br />number. Peak flow estimates should also make slope and <br />basin shape adjustments." <br />The firm of Leonard Rice Consulting Water Engineers <br />(LRCWE) has re-calculated culvert peak flows and <br />culvert sizes for EFC. Curve Number 90 (AMC-II) <br />was used for disturbed areas, and basin shape and <br />slope adjustments were made. Backup calculations <br />are contained in Appendix C which has been added <br />to Exhibit 13. EFC Maps 13, 14, 35 and 36, have <br />been revised accordingly. <br />12/20/79 Memo, p.3, #2 <br />(Class I) <br />"2. Judging from the map, culvert spacing is not in <br />compliance with Federal Regulations." <br />The culvert spacing referred to here is that <br />spacing referred to in 30 CFR 816.153 (c) (2) (i) <br />for "road-surface drainage only." EFC requested a <br />clarification of this regulation on August 22, <br />1979, in a telephone conversation between EFC's <br />John Gates and OSM's John Hardaway. John Hardaway <br />said an example of a culvert that passed "road- <br />O~ surface drainage only" would be a culvert that <br />drains the ditch on the roadside of the safety <br />beams. It can be determined from examining <br />Figures 40, 41 and 42 and Map 37 that the Road <br />Surface Drainage Culverts (RSDC) are spaced in <br />accordance with 30 CFR 816.153. <br />12/20/79 Memo, p. 3, #3 <br />"3. For class I roads, the road-surfacing material is <br />to be removed rather than covered with topsoil as is <br />