Notes
Memorandum dated 04/06/98 from Paul Tappel to Jim Kelley (fax) identifying minor inconsistencies and technical questions in the SeaTac JARPA permit application, AR023893–AR023895. Issues noted include: misaligned V-shaped bypass structure on Sheet 4 of 44; stream buffer width discrepancies (50′ vs. 25′); missing airport security road on Sheet 9; elevation mismatches on Sheets 10, 11, 12, and 18; incorrectly drawn channel cross-section Sheet 18; Sheet 10 showing Miller Creek relocation in a 10′-deep cut with questionable existing grade; Sheet 13 hydraulic cross-section using Manning’s equation with n=0.035 (questioned as too low, suggested 0.06+); log structures vs. rock weirs on Sheet 23; Section 3.3 language on sinuous reconstructed channel described as misleading; Table 4.1-1 average base flow of 5 cfs inconsistent with Sheet 13 cross-section; Section 6.3.4 channel design methodology criticized; Sections 6.5.1.3 and 6.5.1.4 described as unrealistic; conflicts between WDFW riparian planting requirements and bird strike/wildlife attraction concerns; and ponded area drainage criteria eliminating small-scale retention/detention storage and potentially offsetting 61 acre-feet of wetland fill.