Notes
Email chain (Exhibit 2061, AR031718-AR031720) dated February 26, 2001, from Jerald LaVassar (Ecology Dam Safety Office) to Ann Kenny (Ecology), responding to Andrea Grad (Helsell law firm, representing ACC/Airport Communities Coalition). LaVassar explains why the Mechanically Stabilized Earth (MSE) wall at Sea-Tac Airport’s third runway project does not qualify as a dam under WAC 173-175-020, citing the 10 acre-feet impoundment threshold, free-draining backfill design, and the requirement that stored water be above natural ground level. Ann Kenny’s February 8, 2001 email confirms Ecology’s Dam Safety Office determined the MSE wall does not require a Dam Safety permit, identifies two proposed stormwater facilities (25.5 acre-foot SDW1A pond and 37.91 acre-foot SDW1B pond) that may require Chapter 173-175 WAC review, and notes ISW Lagoon #3 expansion was already reviewed. Andrea Grad’s February 15, 2001 PDA (Public Disclosure Act) request seeks all documents relied upon by Ecology in making the MSE wall dam safety determination. The 401 water quality certification process and NPDES permit are also referenced.