Notes
AR023797. Letter dated October 21, 1999 from Kevin C. Fitzpatrick, Supervisor, Industrial Wastewater Permit Unit, NWRO Water Quality, Washington State Department of Ecology to Tom Hubbard, Surface Water Program, Port Of Seattle, regarding the Dissolved Oxygen De-Icing Study (Final Draft) submitted August 16, 1999 in response to an anticipated 401 Certification monitoring requirement. Reviewers Lisa Austin and Tom Luster co-reviewed. Ecology identifies deficiencies including: BOD5 discharges to NW Ponds and Lake Reba; absence of Streeter-Phelps analyses for Des Moines and Miller Creeks; highest BOD5 concentration of 1,176 mg/l in Des Moines Creek East Basin; glycol drip from aircraft as constant stormwater BOD5 source; erroneous use of Class A dissolved oxygen criterion instead of Class AA (9.5 mg/L) per NPDES permit and 401; inadequate sample size (two de-icing events); background based on single day December 9, 1998; use of tributaries as controls instead of upstream/downstream points; correction factors for in-stream DO measurements ranging from -1.43 mg/l to +5.2 mg/l; and general DO criterion non-compliance in upper watersheds. Port outfalls SDE4 and SDS1 identified as potential BOD5 sources. Ecology declines to make a fully informed decision and invites resubmission with addendum. NPDES permit, PCHB Third Runway EIS administrative record.