Notes:
ROBIN M. TOWNE AND ASSOCIATESJ INC. (RMTA)J IN ASSOCIATION WITH MANACOUSTICS
AND NOISEJ INC. (MAN)J BOTH FIRMS OF SEATTLEJ WASHINGTONJ HAVE
BEEN RETAINED BY THE PORT OF SEATTLE AND KING COUNTY TO CONDUCT THE NOISE
EXPOSURE PORTION OF THE SEA-TAC COMMUNITIES PLAN. THE PRIMARY DIVISION
OF WORK CONSISTSJ IN GENERALJ OF ROBIN M. TOWNE AND ASSOCIATES TAKING AND
REDUCING THE ACTUAL NOISE MEASUREMENTS AND MAN-ACOUSTICS AND NOISE PERFORMING
THE COMPILATION AND ANALYZATION .OF THESE NOISE MEASUREMENTS.
ALL AVAILABLE WEATHER AND AIRCRAFT OPERATIONAL DATA ARE BEING GATHERED TO
FORM A BASE FOR NOISE MEASUREMENT. INITIAL SURVEY MEASUREMENTS WILL BE
RECORDED AT VARIOUS TIMES AT SIX LOCATIONS IN THE COMMUNITY SURROUNDING
SEA-TAC. ANALYSIS OF THESE MEASUREMENTS AND FLIGHT PATHS WILL DETERMINE
LOCATIONS FOR FUTURE INSTRUMENT SITES. THE SIX SELECTED LOCATIONS ARE
AS FOLLOWS:
PARKING LOT OF RAINIER GOLF AND COUNTRY CLUB
PRESBYTERIAN CHURCH PARKING LOT AT S. 12~TH ST. AND 19TH AVE.
20TH AVE. SO. AT SO. 141ST ST. (SUNSET JUNIOR HIGH SCHOOL)
18TH AVE. SO. AT SO. 206TH ST.
SO. 222ND ST. AT 19TH AVE. SO. (SCHOOL PARKING LOT)
PARKING LOT AT HIGHLINE COLLEGE (APPROXIMATE INTERSECTION OF SO. 256TH ST. AND 22ND PL. SO. EXTENSIONS).
THE SIX LOCATIONSJ THREE NORTH AND THREE SOUTH ARE ALL C60SE TO THE RUNWAY
ALIGNMENT AND ARE AT DISTANCES OF 5JQQQJ 16J000J OR l~JQQQ FEET FROM
THE END OF THE RUNWAYS.
THE NOISE MEASU~EMENTS OBTAINED AT THESE SITES WILL BE COMPUTED TO ACTUAL
NOISE EXPOSURE {ANE) VALUES TO PROVIDE CONTOURS OF NOISE IMPACT. PREDICTIONS
FOR THE FUTURE WILL BE MADE AND A BACKGROUND NOISE SURVEY WILL HELP
DEFINE NON~AIRPORT-GENERATED NOISE (VEHICULAR TRAFFIC AND INDUSTRIAL NOISE)
AND COMPARISONS WILL BE MADE WITH THE INITIAL SURVEY MEASUREMENTS.
USING INITIAL SURVEY FINDINGSJ A MORE COMPREHENSIVE MEASUREMENT GRID USING
60 DIFFERENT SITES AROUND SEA-TAC WILL BE ESTABLISHED AND CALIBRATED RECORDINGS
WILL BE MADE. RESULTING WILL BE A SERIES OF TABLES SHOWING THE
NOISE DENSITYJ DURATIONJ AND FREQUENCY AT EACH MEASUREMENT SITE CAUSED
BY FLY-OVERS.
A RECOMMENDED ALTERNATIVE WILL BE PRESENTED AFTER ALL MEASUREMENTS AND
EVALUATIONS OF ALTERNATIVES ARE COMPLETED. ALTERNATIVE LAND USES WILL BE
EVALUATED IN CONJUNCTION WITH OTHER ENVIRONMENTAL DATA. PUBLIC PARTICIPATION
WILL BE IMPORTANT IN VALIDATING THE NOISE EXPOSURE CRITERIA AND
GUIDELINES. THE CONSULTANTS SHALL ALSO CONSIDER AND DISCUSS STRUCTURAL
VIBRATIONS CAUSED BY AIRCRAFT OPERATIONSJ INCLUDING EVALUATION OF THE
REPORT MATERIAL PREPARED BY THE SCHOOL OF PUBLIC HEALTH AND COMMUNITY MEDICAREJ
UNIVERSITY OF WASHINGTONJ AND THE HIGHLINE PUBLIC SCHOOLS
