Air Carrier on final to Runway 16R at SEA received a TCAS RA; apparently resulting from ATC issued traffic operating at Boeing Field traffic.

Narrative

Location: Approximately 5.2 NM final; Alt.: Approximately 1600 FT. AFL. ILS 16R approach. SEA. ATC had given at least two traffic advisories for traffic off of Boeing Field (one as a departure at Approximately 600 FT.) Traffic never visually acquired during evolution. Aircraft in final landing configuration. Received TCAS climb RA. Immediately implemented and executed QRH procedure for climb RA in landing configuration. During GA received increase climb RA. Almost immediately into procedure clear of conflict resolution received. GA for TCAS RA reported to ATC with a request to pass to company. Subsequent vectors for another approach and uneventful landing accomplished. Coordination occurred with FTWD; ATC; Flight Attendants; NTSB; Tech; Chief Pilot on duty; etc. At gate; immediately after gate arrival; notified SEA Tower that evolution satisfied criteria for categorizing as a NMAC event. Also; followed up with a radio call to FTWD. Cb. F-6 pulled as precaution. Jump seat rider stated TCAS display showed 200 FT initially and 100 FT when Clear Of Conflict received. While distance was less than 500 FT and technically satisfied criteria for NMAC because prescribed procedures were not delayed safety of flight was not jeopardized and evasive maneuvers were not required. For the same reason; while a risk of collision existed; due to timely implementation of prescribed procedures substantial risk of collision was averted. For any reader of this report it is important to emphasize that less than a timely response to TCAS RAs could potentially result in an undesired outcome.