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Chapter IV, Section 1 - Noise Impacts
General.
Introduction to Comments on Chapter I. Our comments on
this Chapter are in two groups. In the first group, Comments
I-A through I-F, we include six studies of certain issues
included within the scope of the Chapter; these studies
present materials, data, findings, & analyses not included
in the DEIS, which should be addressed in the FEIS. In the
second group, Comments I-G through I-N, are our comments on
particular points raised in the DEIS or suggested by it.
Listing of items included as Comments I-A - I-F:
Comment IV-1-A: A Comparison of FAA Integrated Noise
Model Flight Profiles with Profiles Observed at Seattle-
Tacoma by George W. Flathers, II December 1981 Report No.
FAA-EE-82-10
Comment IV-1-B: FAA Advisory Circular 36-1F Noise Levels
for U.S. Certificated and Foreign Aircraft, June 5, 1992
Comment IV-1-C: Preliminary Noise Analysis of the
Proposed FAA 4 Post Plan Noise Mediation Options
Subcommittee - January 4, 1990
Comment IV-1-D: FAA Decision and Order issued April 2,
1990 by Temple H. Johnson, Jr. Manager, Air Traffic
Division, Northwest Mountain Region, Federal Aviation
Administration
Comment Iv-1-E: Jorgen Bader, Letter to Editor Seattle
Times dated April 6, 1990 re: FAA Decision and Order
issued April 2, 1990
Comment IV-1-F: Letter from Laurene McLane former member
of SeaTac Noise Advisory Committee (SNAC) to SeaTac Noise
Advisory Committee dated August 16, 1993
Comment IV-1-G: Single Event Aircraft Contribution to
SeaTac Ldn Levels prepared for Regional Commission on
Airport Affairs by Errol Nelson, PE - Optimum Environment
Inc. - October 27, 1994
Comment IV-1-H: Comparison of Measurement Weighting
Metircs near SeaTac prepared for Regional commission on
Airport Affairs by Errol Nelson, PE - Optimum Environment
Inc. - April 17, 1995
Comment IV-1-J: Memorandum to Expert Arbitration Panel -
Puget Sound Regional council from Errol Nelson, PE - Noise
Consultant to RCAA Re: Testimony at August 11, 1994 hearing
of Expert Panel
Comment IV-1-K: RCAA Input to Attachment 2 to Procedual
Order Information Requests to the Public prepared by G.
Bogan & Associates, Inc.
Comment IV-1-L: Implementation of an LDA/DME Approach to
Runway 16R in Lieu of a Third Runway at SeaTac Airport
prepared for the Regional Commision on Airport Affairs by G.
Bogan & Associates Inc. June 26, 1995
Comment IV-1-M: Order on Phase 1 Noise Issues issued
January 9, 1995
Comment IV-1-N: Expert Arbitration Panel, Transcript of
May 4, 1995)
Comment IV-1-O: Interim Technical Addendum Regarding the
city of Chicago's Use of the Integrated Noise Model State
of Chicago ex. rel. Ryan vs. City of Chicago 18th Judicial
District Court Dupage County, Illinois
Comment IV-1-1 Noise is a complex phenomena and current
methods of measurement are crude. Although loudness can be
measured in decibels, existing instruments cannot determine
many of the physiological effects of noise. An example is
when the sound of finger nails on a blackboard causes human
beings to cringe.
A nationally recognized noise expert recently observed that
the measurement of noise does not occur for its own sake and
noted "most people understand that if aircraft noise did
not affect people, nobody would go to bother and expense of
measuring it".1 A fundamental conslusion which may be
gleaned from this assertion, is that the meaning of the term
"noise" is separate and distinct from the the effects which
noise produces, or the "noise impacts" on human beings and
their surrounding environment. In other words, a noise
level is not a noise impact.2 The central focus of the DEIS
must therefore be the effects of noise, both under the
existing conditions, as well as the proposed alternative
conditions, on people and their surrounding environment, not
on microphone diaphrams.3 Merely because some faceless
technocrat preparing (or revising) an EIS understands how to
spell decibel does not mean this person is appointed,
elected or in any way qualified to specify what is a
meaningful noise impact.
Comment IV-1-2 Sea-Tac airport sits on just 2400+ acres
in the middle of an existing densely populated area. The
North/South runways send heavy jet aircraft low over the
most densely populated metropolitan corridor north of San
Francisco and west of Minneapolis. Sea-Tac has the third to
the fifth worst noise exposure problem in the nation,
comparing the source of the noise (number of operations) to
the number of people living in the high noise areas. 4
Many thousands more live in the still bad 55 LDN area.
Still more live in the 45+ LDN upon which residential
neighborhoods are affected 5. The DEIS should address why
the third to fifth worst noise impacted mini-sized airport
in the US should be even further impacted with up to one
third more flights.
Comment IV-1-3 A large increase in the number of
operations occured At SeaTac during the 1970's and 1980's.
During this time flight operations increased from 114,372
per year in 1971 to 345,000 operations per year in 1990. 6
Also, in 1989 the FAA changed the approach and departures
flight tracks to SeaTac under the "Four-Post Plan" Both
actions have produced widespread complaints of increasing
airport noise produced by the airport operations at SeaTac.
Comment IV-1-4 FAA regulations require that the noise
impacts associated with the proposed actions and the
alternatives to those actions be considered in the E.I.S.
Accordingly, noise levels at all alternatives including each
of the supplemntal airport sites, Paine Field, McChord,
King County International Airport. and all other sites must
be considered in this DEIS. Accordingly, the E.I.S. must
examine the increased noise impacts that would result from
increased operations at Sea Tac under the Port's proposal
and under each alternative. Noise levels at the proposed
supplemental airport sites must be considered in the DEIS.
Despite efforts by PSRC's executive board (Resolution EB-94-
01) to delay a search for a supplemental regional airport
sites the study of alternative sites has not been foreclosed
by the Puget Sound Regional Council therefore, noise
impacts on populations areound each of the proposed
supplemental airport sites should be studied in this EIS.
As previously stated, the central focus of the DEIS must be
the effects of noise on people at each of the alternatives.
In Chapter 2, the results of the Major Supplemental Airport
Feasibility Study are included. The population exposed to
noise levels of 45 dBA, 50 dBA, 55 dBA, 60 dBA, 65 dBA, 70
dBA, 75 dBA, 80 dBA, 85 dBA, 90 dBA and above, using both
the DNL and SEL metrics, should be published in the FEIS to
show the relative population impacted under each of the
alternatives.
Comment IV-1-5: This impact statement must discuss and
fully disclose the existing, actual noise levels (not just
computer generated predictions,) at SeaTac. It must also
address projected increases, and detailed mitigation plans
including costs, timing, etc.
The impact of aircraft and surface transportation noise
levels upon the communities surrounding the Airport is
presented in this section. The analysis includes
determination of impacts on the surrounding area in 1994 and
as forecast for the years 2000, 2010 and 2020.
The difference between the noise impacts of the three "With
Project" alternatives are very small:
Aircraft Noise (DNL 65 and Greater)
Population Housing sq- mi.
1994 31,800 13,620 9.31
2000
Altern. 1 8,790 3,510 3.40
Altern. 2 9,890 4,020 2.87
Altern. 3 9,890 4,020 2.86
Altern. 4 9,890 4,020 2.86
2010
Altern. 1 9,450 4,060 3.54
Altern. 2 9,870 4,190 2.97
Altern. 3 9,860 4,190 2.98
Altern. 4 9,860 4,190 2.98
2020
Altern. 1 10,800 4,610 3.97
Altern. 2 11,270 4,760 3.31
Altern. 3 11,240 4,740 3.34
Altern. 4 11,270 4,760 3.34
Note: Altemative 1 = Do-Nothing,
Alternative 2. 3 & 4 are "With Project".
All "With Project' alternatives include a new dependent
(2,500 ft separation) parallel runway with a length up to
8.500 feet. Area is non-airport land.
Comment IV-1-6: The DEIS states "[t]he difference
between the noise impacts of the three "With Project"
alternatives are very small:" The DEIS should quantify and
define the meaning of the term "small."
After dismissing the noise impacts under all proposed
alternatives as "small" with no prior analysis, the DEIS
immediately assumes the use of the metric DNL and
establishes the metric "DNL 65 and greater" as the threshold
which establishes the population, housing, and area
subjected to noise "impact". No explanation, methodology,
or reference is provided explaining:
Comment IV-1-7: The FEIS should provide a comprehensive
search of the literature, which cites all references,
documentation, and the scientific basis explaining:
(a) Why the DEIS establishes the metric DNL as an adequate
descriptor of noise impacts.
(b) Why DNL 65 establishes the threshold of impacts using
the DNL metric.
(c) What noise metrics are useful in determining the
impacts of noise upon people.
(d) Using metrics other than DNL, what metrics are useful
in determining the effects of noise impacts upon human
beings, residences, and the natural environment.
(e) How metrics for comparing noise impacts are related and
how they are distinguished
Comment IV-1-8: In a recent rule making,7-- the FAA
apparently endorsed the EPA's position that it should
"modify the definition of (noise study area] so as to
eliminate the perception that the area with the DNL 65 dB
contour is the sole area to be considered for noise impacts,
while retaining the flexibility of extending beyond the DNL
65 dB contour. We note that the daily LDN for a stick of
dynamite (194 decibels) would be zero. This mathematical
phenomenon explains why people who live with aircraft noise
find the LDN metric so inadequate as the sole measure. The
DEIS must acknowledge, therefore, that relatively low
average noise levels (lower than 65 DNL) can adversely
affect a community when pre-existing noise levels were
comparatively low or when single noise events are
particularly intrusive. It must further explain the effects
of these noise levels below DNL 65 on a community.
Comment IV-1-9: The authors of the DEIS are responsible
for researching and articulating existing standards,
methodologies and thresholds used to determine whether the
impacts of noise assiciated with the project and
alternatives are sufficiently addresed in the DEIS. Many
authorities hold that metrics supplementary to the DNL are
necessary to determine the impacts of aircraft noise upon
populations. For a detailed synopsis of these authorities
see RCAA comments on DEIS Chapter IV, Section 7 titled Human
Health. This section should discuss in detail, how project
and alternatives, would affect the SEL noise contours
surrounding SeaTac airport and show maps protraying the 80
SEL, 85 SEL, 90 SEL, 95 SEL, and 100+ SEL noise contours.
For example, show how the diversion of commuter air traffic
to rail would affect the noise impacts on the population
exposed to noise levels of 45 dBA, 50 dBA, 55 dBA, 60 dBA,
65 dBA, 70 dBA, 75, dBA, 80 dBA, 85 dBA, 90 dBA using both
the DNL as well as the SEL noise metric. Also provide a
compaison of the same decibel levels using the C-weighted
noise metric and the incidences and cumulative amount of
time during which noise levels occur which exceed these
levels (TA) using both the A-weighted and C-Weighted noise
metrics.
Comment IV-1-10: Recently, a panel of experts reviewing the
issue of noise reductions in communities affected by noise
from SeaTac airport noted "the use of the DNL metric by
itself, is inadequate to show the required reduction in
noise impacts because, taken alone, as an aggregate value it
does not permit us to review the intensity, duration or
frequency of single noise events or to consider when, during
the day or night, they occur (even though all of these
attributes contribute to teh measured DNL) As a result, we
encourage the POS [Port of Seattle] to develop a method that
supplements the use of the DNL observations with various
additional metrics(including sound exposure level (SEL),
Time Above (TA) an appropriate sound level threshold, and
unweighted sound pressure levels). The revised mothod should
also explicitly report changes in the total number, as well
as in the composition and day/night mix, of aircraft
operations at the Airport. Unless the reduction in sound le
vels is more fully characterized than the use of only DNL
allows, we will be unable to find that there has been a
meaningful reduction in real on-the ground noise impacts,
...". 8
Comment IV-1-11: This expert panel also found that areas
subjected to noise impacts "should include sites beyond the
boundaries of the predicted 65 dB DNL contours" and "farther
out along major flight corridors and farther out to the east
and west of the airport." 9 We agree and the Final EIS
should do so.
Comment 1-8:
SUTER
Other authorities have also held the findings of the expert
panel on the sbject of both noise metrics as well as the
threshold detrmination of what populations are affected by
noise impacts. For a detailed exposition of current
scientific literature on the subject of the effects of noise
on humans see Chapter IV, Section 7. The FEIS should
contain all references to the literature which substantiates
its claim that DNL 65 is the threshold for determing
aircraft noise impacts.
Comment IV-1-12: In studying the effect of noise in the
classroom one of the authors of the present EIS recently
admitted "...[N]oise levels up to 35 dBA will allow
satisfactory speech communication in a normal voice level up
to a distiance of 32 feet. The sound level of 45 dBA is
used since it represents average teacher to student distance
of 16 feet, where a normal voice level is satisfactory for
communication. 10
Comment IV-1-13: In discussing the issue of various noise
levels on specch interference inthe classroom, the preparer
of the current EIS discussed the relationship between
interior and exterior noise in the classroom teaching
environment"
[Ms. Vigilante] A. I can't speak to the ability to
conduct education at a sound level. I can speak to the
normal criteria for speech interference. And in any
instance where the sound levels are in excess of 65 Ldn
the interior sound level would be in excess of 45
decibels, and, therefore, speech would be interfered
with.
Q. So you are saying, when you have an exterior of
65, it is normally considered the fact that the
resulting interior will be in excess of 45, and that 45
interferes with normal speech pattern?
A. In excess of 45 will interfere with normal speech
communication.
Q. All right. So that we have this straight now.
The sequence then is as a rule of thumb, an outside or
external of 65 or greater will produce an internal of
45 or greater, is that right?
A. In a normal northern climate structure with the
windows closed, you normally will get a 20 decibel
attenuation.
Q. With the windows closed?
A. Yes.
Q, What attenuation do you get with the windows
open?
A. It can vary, but normally around 15.
Q. Normally around 15 and can it be less that?
A. It can be less.
Vigilante deposition, page 141 (emphasis
added) 11
Q. So that if you have a decibel level of 60 with the
windows open, you can have interference with speech
communication, can you not?
A. If those conditions exist, presumably yes.
Vigilante deposition, page 142 (emphasis
added)
Relying solely on its "contour" map and no actual
witness or actual measurements, the preparer of the
DEIS has suggested that the schools outside SeaTac's
INM "contour" map are not adversely affected by noise.
But on examination, Mary Vigilante
admitted that her INM model showed many hours per day
of noise interference at the schools which had not yet
been soundproofed. 12 As to those schools, Exhibit 11
shows the hypothetical average number of minutes per
day that the aircraft noise level at these schools is
estimated by Chicago's INM model to be above 65 dBA:
The Court should be aware that these values are most
likely bogus. They are based on an INM model, the
inputs to which produce the classic "GIGO" ("Garbage
In, Garbage Out") (see discussion below). But they are
the numbers that Chicago claims represent "scientific"
and "objective" measures of the noise experienced at
these schools. Accepting arguendo these numbers, it
means that for each of the schools, the aircraft
induced noise totals several hours per day above the
level that Chicago's own witness says causes
interference with speech communication in the
classroom. For example:
Q. For Medinah South, according to your computer
model, Medinah South has these numbers time above 65
which represents the minutes in a day, isn't that
right?
A. That is correct. Minutes in a 24-hour period.
Q. And with respect to the minutes in the 24-hour
period, that would be 214 minutes for 1983, would it
not?
A. That is correct.
Q. That is according to my arithmetic about three
and a-half hours?
A. Approximately.
Q. In the day?
A. Yes.
Q. And according to the way you calculate the INM,
that's the average number of hours per day over a year
that school --
A. That's correct, it is an average annual condition.
Q. So there are days by definition, because it is an
average annual, where the number of hours that that
school gets hit with, the numbers of minutes are less
than 214; and, there are also days where the number of
minutes is greater than 214, isn't that tight?
A. That would be correct.
Q. That would be true for the minutes of exposure in
Exhibit 11 for any of the schools mentioned, isn't that
right?
A. They would represent average conditions, yes.
Q. So my statement and your answer with respect to
the fact that by using an average, it necessarily means
that all of the schools are exposed to 65 decibels on
some days less than the number shown in Exhibit 11 to
Vigilante Deposition Exhibit No. 9, and on other days
more than the number of minutes shown on Exhibit 11 to
Vigilante Deposition Exhibit No. 9?
A. That is correct.
Q. So for Sandburg Junior High for example, which is
school 22, you show in 1983 that it experiences noise
at -- is that two and a-half hours a day above 65?
A. Approximately 152.7, which is about two and a-half
hours.
Q. All right. Based on the use of the annual
average, that necessarily means that some years or some
days I should say within the year, that the noise
exposure at Sandburg in 1983 was less than 152 minutes
and on other days it was more?
A. That is correct.
Q. Do you know the range, for example, for Sandburg
Junior High School, take for example 1983, the range,
the minimum number of minutes that it would be affected
by aircraft noise on a given day versus the maximum
number of minutes, 152.7 being the average?
A. I do not know the minimum or the maximum.
Vigilante deposition, pages 142-44 (emphasis
added)
Thus the DEIS's own witness demonstrates its admission
-- hoist by the petard of its own "scientific" computer
model -- that all of the schools (including the schools
not yet soundproofed) suffer from several hours per day
-- some days more, some days less -- of significant
noise interference above the levels which its authors
say interfered with speech communication in classrooms.
Yet the author suggests in its DEIS that these schools
are not adversely impacted by noise.
The FEIS should identify and locate on a map all schools
where classroom interior noise levels caused by each of the
proposed alternatives would exceed 45 dBA. The FEIS should
discuss the relationship between interior and exterior noise
in school classrooms, especially in classrooms not equipped
with air conditioning where exterior windows must be opened
to provide adequate ventilation in classrooms. The FEIS
must identify the total number of aircraft noise incidences
and total minutes per school year for each school where
exterior noise levels exceed 60 dBA, and interior noise
levels exceed 45 dBA.
Comment IV-1-12: In order to gain a satisfactory
understanding of the meaning of the term "noise impacts" the
preparer of the correct DEIS should visit each of the
schools presently impacted with aircraft noise levels of 60
dBA and above.
Because the new dependent parallel runway is proposed to
reduce poor weather delay, which is predominantly arrival
related, the runway would be expected to be used primarily
for arrivals. About 12.1 percent of arrivals in a south
flow would occur on the new runway, with about 2.6 percent
of departures. Greater departure use would not be expected
due to the distance of the runway from the terminal complex.
Comment IV-1-13: The DEIS states "because the new dependent
parallel runway is proposed to reduce poor weather delay,
which is predominantly arrival related, the runway would be
expected to be used primarily for arrivals." Recently
however, FAA officials have disclosed that the delay
calculations for the 3rd runway in the DEIS are based on a
computer simulation model (SIMMOD) which has not correlated
the relationship between the airport's demand profile and
weather variations when calculating the delay figures
published in the DEIS.13 Additionally, a recent study has
challenged the 44% "bad weather" figure cited in the DEIS.14
This study proposed the addition of existing navigation
technology in the form of a Localizer Directional Aid (LDA)
aircraft navigational system to allow parallel dual stream
arrivals under weather conditions with ceilings as low as
2200 feet, a system which obviates the need for a third
runway. (For a detailed exposition of LDA see Chapter II,
Purpose and Need.) The FAA's 1993 Aviation System Capacity
Plan LDA recommendeds LDA as an impreovement to SeaTac's
existing airfield including provision on an LDA approach to
Runway 16L/34R 15 The DEIS must consider potential noise
impacts caused by implementation of this FAA recommended
approach procedure which according to the recent study
referenced above, would obviate the need for a third runway
at SeaTac. Care should be take to analyze the noise impacts
of LDA approaches only when capacity needs required such
approaches. The study cited above concluded this would
ooccur less than 2% of the time.
Comment IV- 1-14: The foregoing discussion raises concerns
about the accuracy of noise predictions based upon
consideration of weather conditions different from those
projectsed in the DEIS as well as the effects which
implementation of the FAA recommended LDA navigational aid
would have on noise impacts. This in turn raises the issue
of the impacts of proper utilization of flight tracks used
to develop the INM noise contours for the proposed third
runway. If the need for the third runway is obviated by
the use of an LDA system and instead is used instead
predominantly for takeoff's, then the noise contours
related to a third runway are obviously not modeled
correctly in the DEIS and must be recalulated.
As shown above. the number of people, housing units, and
area affected by DNL 65 and greater sound levels are
expected to decline in the future in comparison to 1994
noise exposure regardless of future development at Sea-Tac
Airport. This decline in impacts is expected due to the
Port's noise reduction program and the Federal mandate to
phase-out Stage 2 aircraft no later than the year 2000.
This analysis focuses on the impacts within DNL 65 and -
greater noise exposure; however, areas exposed to DNL 60-65
were evaluated and are presented for information purposes.
Comment IV-1-15: The DEIS states the number of people,
housing units, and area affected by DNL 65 and greater sound
levels are expected to decline in the future in comparison
to 1994 noise exposure regardless of future development at
Sea-Tac Airport. The DEIS states this decline in impacts is
expected due to the Port's noise reduction program and the
Federal mandate to phase-out Stage 2 aircraft no later than
the year 2000. This DEIS further confines its analysis to
"the impacts within DNL 65 and -greater noise exposure;
however, areas exposed to DNL 60-65 were evaluated and are
presented for information purposes."
Comment IV-1-16: The phase out of stage 2 aircraft is
currently required under 14 CFR pt. 161, the Airport Noise
and Capacity Act (ANCA). Under an exemption to the ANCA
Act, the Port of Seattle is conducting a program to phaseout
existing stage 2 aircraft operating at SeaTac which do not
meet noise certification requirements specified in 14 CFR
pt. 36 titled Noise Standards: Aircraft Type and
Airworthiness Certification. At present SeaTac's fleet is
comprised of approximately 83% Stage 3 aircraft. 16 the
FEIS should provide a detailed analysis explaining how
signifigant noise reductions will occur if the remaining 17%
of SeaTac's existing Stage 2 fleet is phased out through a
33% increase in Stage 2 and Stage 3 flight operations
predicted in the DEIS.
Comment IV-1-17: The DEIS assumes that all Stage 2
aircraft are quieter than Stage 3 aircraft. In fact many
cases stage 3 noise certifications reduce aircraft engine
noise by only 3 dBA to 5 dBA forequivalent aircraft. 17 The
statement in the DEIS that noise levels will be reduced due
the conversion of the remaining 17% of its fleet to Stage 3
aircraft, while expnding operations to a level of 38 million
passengers per year from its current level of 20 million is
not rational, and must be substantiated with a detailed
explanation and documentation.
Comment IV-1-18: Also equivalent stage 3 aircraft produce
noise levels which vary signifigantly in noise depending on
engine configuration and other characteristics including
aircraft weight. For example, a Stage 3 Boeing 767-200
aircraft equipped with Model CF6-80A2 engines with a mean
take off weight of 279.9 thousand pounds produces an
Equivalent Perceived Noise Level (EPNL) of 84.2 dBA during
takeoff. 18 However the same aircraft with the same engines,
loaded with a mean take off weight of 360.0 thousand pounds
produces an EPNL of 91.7 dBA ( 7.5 decibels higher) during
takeoff.
The statement in the DEIS that noise levels will be reduced
due the conversion of the remaining 17% of its fleet to
Stage 3 aircraft, while expanding operations to a level of
38 million passengers per year from its current level of 20
million is not rational, and must be substantiated with a
detailed explanation and documentation.
Comment IV-1-19: Additionally, comparing noise levels
between Stage 2 and Stage 3 aircraft, a Stage 3 Boeing 747-
100 with a mean takeoff weight of 710 thousand pounds
produces an EPNL noise level of 104.6 dBA on approach 19
while a Stage 2 Boeing 727-100 produces an EPNL noise level
of 97.8 EPNL on approach, 20 a 6.8 decibel difference. The
statement in the DEIS that noise levels will be reduced due
the conversion of the remaining 17% of its fleet to Stage 3
aircraft, while SeaTac's operations expand to a level of 38
million passengers per year from its current level of 20
million is thus non-sequitur, and must be substantiated with
a detailed explanation and documentation.
The development of a new parallel runway would be expected
to result in as much as a 4.4 percent increase in dwelling
unit impacts over the Do-Nothing altemative in the year
2000. However, in all instances, these future impacts would
be less than the current noise exposure. A 7,000-ft long,
new runway would result in lesser noise impacts in
comparison to the longer 8.500-foot. However, a 7,000-foot
longer runway, with a north threshold staggered south. could
result in even less impacts than the shorter 7,000-foot long
runway.
Comment IV-1-20: The DEIS states development of a new
parallel runway "would be expected to result in as much as a
4.4 percent increase in dwelling unit impacts over the Do-
Nothing altemative in the year 2000. However, in all
instances, these future impacts would be less than the
current noise exposure." As discussed above decreasing
noise impacts must be predicated upon the validation of the
INM model noise contours and certification of the noise
levels in the affected areas by independent means. The
Noise Expert Panel recently rejected the Port of Seattle's
proposed noise reduction methodology including the Port's
Nighttime Limitations Program and phaseout of Stage 2
aircraft as a valid method of producing reductions of noise
impacts on the affected communities. 21 Mediation Agreement.
used in conjunction with the Port's of the existing noise
levels by a in the affected
The DEIS also states "a 7,000-foot longer runway, with a
north threshold staggered south. could result in even less
impacts than the shorter 7,000-foot long runway."
Ground noise associated with North Unit Terminal (Altemative
4) would result in the greatest noise exposure, while
Alternative 3 (South Unit Terminal) would produce the least
"With Project" impacts. Detailed information relative to
the level of aircraft noise impacts within each jurisdiction
surrounding the Airport is presented in Chapter IV, Section
2 .Land Use".
While this analysis has focused on the areas exposed to DNL
65 and greater sound levels, it is anticipated that changes
in noise exposure could also occur outside the DNL 65. For
residents that are disturbed bv noise less than DNL 65,
these impacts could continue and change slightly. As is
shown by the assessment of noise impacts caused bv aircraft
flying at altitudes between 3,000 feet and 18,000 feet
(provided in Appendix C), these impacts are not expected to
be significant.
The proposed Master Plan Update alternatives would affect
the volume of traffic using area roadways. To evaluate the
impact on area roads, the Federal Highway Administrations
noise model STAMINA-2.0 was used to assess the peak hour
average sound level [Leq peak-h,,]. The proposed new
parallel runway would not affect area roadway,,, noise.
The terminal and landside development within the Master
Plan, Update alternatives would alter the use of roads, and
result in increased noise at some residential/incompatible
locations and decreased noise at other locations. The
roadway noise analysis indicates that the greatest change in
roadway noise would occur with the development of the SR-509
Extension and South Access Road (a Do-Nothing and "With
Project" action that is expected to be undertaken bv the
Region). The greatest increase in noise and "With Project"
alternatives relative to the Do-Nothing would range between
1.0 dBA and 2.8 dBA and would occur in the corridor of the
South Access Road, Without the South Access Road, the
greatest increased noise, in comparison to the Do-Nothing
would occur along International Blvd., south of 188th.
(1) AIRCRAFT NOISE EFFECTS
For the purpose of this evaluation, aircraft noise impacts
represent the land area and number of people and residences
exposed to aircraft noise above predetermined levels.
Contour lines representing average annual noise conditions
were generated showing the Day-.night Average Sound Level
(DNL or Ldn) of 60, 65, 70 and 75 dBA for aircraft
operations. The number of existing residents and dwelling
units located within the noise exposure pattern of cur-rent
and each future altemative condition were identified.
The DEIS presents aircraft noise impacts represented only as
land areas and numbers of people and residences exposed to
aircraft noise above predetermined DNL noise levels. Contour
lines representing average annual noise conditions were
generated showing the Day-.night Average Sound Level (DNL or
Ldn) of 60, 65, 70 and 75 dBA for aircraft operations. The
number of existing residents and dwelling units located
within the noise exposure pattern of the noise levels of 60,
65, 70, and 75 Ldn were calculated for each of the the
current and each future altematives. There are many
problems with this approach. First, the selection of the
population residing in areas subjected to 60 through 75 DNL
as the only population affect by aircraft noise woefully
underestimates the extent of the impacts of aircraft noise
upon human beings. Our comments responding to Chapter 4,
Section 7 of the DEIS (Health Effects) explain the
tremendous amount of reaseach on the human health effects
which exist caused by the impacts of noise levels of 45 DNL
and above.
The following sections provide a brief summary of the
methodology-used and the resulting impacts. Appendix C
provides detailed information related to the methodology
used in preparing the noise analysis, statistical
information used in the development on noise contours, and
information related to the impact of noise on people
residing in the vicinity of SeaTac. Chapter IV. Section 7
contains a summary of the human health effects due to noise.
(A) Methodology
Day Night Sound Level (DNL) contours were developed using
the Integrated Noise Model (INM), Version 4.11. The INM is
a sophisticated computer model that evaluates the
cumulative noise exposure of all aircraft operating to and
from the Airport on an average annual day. Noise associated
with the aircraft while on the runway or in flight has been
available since the introduction of the model in 1978.
Version 4.11 of the INM, released by. the FAA in December of
1993, has some new features that allow a standard evaluation
of aircraft noise to include the effects of-.
* Ground terrain
* Run-up noise
* Departure climbs adjusted for local elevation and
temperature
* Aircraft taxiing noise
The new features of the Integrated Noise Model were used in
this analysis.
Comment IV-1-21: See Chapter 4, Section 7
The INM Noise Modeling Program
The DEIS preparer states that the noise contours used in
this part of the report were developed using Version 4.11 of
a computer program developed b the FAA called the Integrated
Noise Model (INM).
The INM computer modeling programs relies, as all computer
models do , upon the accurate input of information into the
to the model used to simulate the physical event or events
modeled. The purpose of any modeling effort is to repoicate
the real world -- i.e. to insure that the results estimated
by the model accurately reflect the real world. In the
field of computer modeling, the process of confirming that
the model accurately mimics the real world is called
validation. 22 As in a recent Chicago case, the preparers of
this DEIS, have failed to validate the INM model to see if
it produces accurate results. As in Chicago "[t]his lack of
validation is made even more egregious by Chicago and
Vigilante's failure thus far to provide the step by step
back-up material and sequencing for the running of the model
so that [commenters] can determine of the model results can
be replicated." 23 Accuracy of the INM relies upon the
periodic calibration of the model to verify that the
physical event or eventsfs modeled comport with the physical
world. If these important steps are not taken and verified,
the results of any computer model will be subjected to
criticism, potential ridiclue, and recitations of the
familiar nostrum: "Garbage In = Garbage Out. The computer
generated noise levels and contour maps produced in the DEIS
are supplied with no evidince or assurance that the results
can be substantiated. Among the backup materials currently
missing are:
a. The sequential steps assigning flights to various runways
and flight tracks.
b. The stasistical and data basis for selection of the
flight tracks used.
c. The data basis for the flight track profiles made in hte
model.
d. The data basis for assigning sircraft and engine types in
the model.
e. The data basis which verifies the physical distance and
height of aircraft used in the model relative to the
recepter site (i.e. rader track data - ARTS data) for the
annual period during which the INM model is calculated.
f. The validation that the above paramters have been
accurately enterd into the input file of the INM modeling
program.
As indicated below, a signifigant body of evidence exists
showing first that the purported noise levels in the DEIS,
under the "Do-Nothing" option have not been substantiated or
corroborated by scientific methodologies, or indepedent
means, and second, that the purported noise levels under the
alternatives are predicated upon a methoological appriach
which casts doubt as to their validity.
According to the DEIS, features allowing the INM model to
include the effects of ground terrain, run-up noise,
departure climbs adjusted for local elevation and
temperature, and aircraft taxing noise were used in this
DEIS analysis.
The following sections provide a brief summary of the
methodology-used and the resulting impacts. Appendix C
provides detailed information related to the methodology
used in preparing the noise analysis, statistical
information used in the development on noise contours, and
information related to the impact of noise on people
residing in the vicinity of SeaTac. Chapter IV. Section 7
contains a summary of the human health effects due to noise.
(A) Methodology
Day Night Sound Level (DNL) contours were developed using
the Integrated Noise Model (INM), Version 4.11. The INM is
a sophisticated computer model that evaluates the
cumulative noise exposure of all aircraft operating to and
from the Airport on an average annual day. Noise associated
with the aircraft while on the runway or in flight has been
available since the introduction of the model in 1978.
Version 4.11 of the INM, released by. the FAA in December of
1993, has some new features that allow a standard evaluation
of aircraft noise to include the effects of-.
* Ground terrain
* Run-up noise
* Departure climbs adjusted for local elevation and
temperature
* Aircraft taxiing noise
The new features of the Integrated Noise Model were used in
this analysis.
Comment IV- 1-22:
Comment IV-1-23: One of the key assumptions used in
developing the INM noise model foar a particular airport are
the flight tracks locations. The INM model allows the user
to assign the route of departing and arriving aircraft
according to a systematic process which assigns aircraft to
particilar flight tracks. Until very recently aircraft
flight tracks, from the standpont of the INM, have been
hypothetical concepts. They are not railroad tracks in the
sky. 24 The locations of flight tracks are subject to the
discretion of the operator of the INM program and much
controvery has existed on the issue of whether the flight
track assignments used in the INM model have accurately
reflected the actual airport situation. 25 The FEIS must
include valid and statistically signifigant flight track
information for annual periods, indicating aircraft type per
operation for each of the alternatives.
Comment IV-1-24: Accurate flight track data from the
FAA's Aircraft Radar Traffic System (ARTS) has only been
available for the past several years. Prior to this time
"consultants for years have exercised considerable latitude
in trying to represent these flight tracks, and its only
been within the last few years that the FAA released the
information which one needs to pin them down." 26 Such
latitude is illustrated In a infamous recent case the court
found that (the preparer of this DEIS may remember) the
preparer of an INM model for a proposed runway expansion
project in the Chicago area, had used flight tracks in the
INM model which did not comport with the tracks she observed
during her observations from a control tower. Flight tracks
used to produce INM noise model contours in the FEIS must be
be verified with ARTS data by aircraft type and statisically
correlated to the INM model input file.
An FAA study 27 has compared INM flight profiles with flight
profiles observed at Seattle-Tacoma airport. This report
noted that the INM database has a set of defined profiles
for wach aircraft type "which were constructed under the
assumption that the FAA procedure is being followed by all
arcraft." 28 the report noted "the INM estimates departure
weight by using stage length". 29
In studying flight profiles this report observed departure
flight tracks and noted that observed altitude profiles for
B-737 aricraft were much lower than the INM profiles for the
portion of the departure within 3 nautical miles of the
Brake Release Point (BRP) 30 In comparing B-727 departures,
this study found and that "the assumption that weight
estimation can be based on stage-lengths may not always be
true." and "differences between INM profiles for the
shortest and longest stage-length tend to be masked by
variation from other sources." 31 and were several times
greater than the sensitivity of the INM to stage length.
This study also observed effects of varying departure
procedures of different airlines including differences of
1000 feet in altitude at 8.5 n.m from SeaTac. 32 The report
recommended that the number of stage-length categories for B-
727 aircraft in the INM noise modeling program be reduced to
two or three. 33
This report came to the stunning conclusion "a possible
reasin for this observation is that the procedures used by
the pilots of these ... aircraft types are not fashioned
after the FAA profile which the INM assumes." 34
A subsequent FAA study of INM flight profiles at SeaTac
Airport also noted that "assumed departure altitudes and
thrust do not comport with the real owrld behavior of planes
actually taking off for commercial airports: .." 35 This
study confirmed that during departures at SeaTac airport :
"At cutback thrust, the INM underestimated observed noise
levels by a considerable margin. This underestimation was
explained by the fact that most airlines do not emply the
deep thrust cutback assimed by the INM, but use the higher
normal climb thrust." 36
Comment IV-1-25: Obviously, the author of the DEIS has
(intentionally?) failed to correct flight profiles in the
DEIS. the authors of the DEIS were aware of these studies
yet have failed to acknowledge or incororate their findings.
The FEIS must provide a detailed explanation of how the
flight profiles in the INM noise model have been validated
with actual flight conditions at SeaTac and recommendations
of FAA studies which recommend modifocations to the standard
INM database flight profiles.
Comment IV-1-26: Chicago's consultant has admitted that the
INM model has not been used in a takings case.
Comment IV-1-27: The EIS claims that the INM model is
widely used as a generic planning tool. However, it ignores
the fact that the quality, accuracy and representativeness
of what is put into the model severely impacts its utility.
Given the demonstrated problems of Chicago and its
consultant in providing accurate inputs to the model, as
well as the admitted limitations of the model itself, it is
little wonder that Chicago's consultant admitted that the
model results have not been used to establish the presence
or absence of a taking:
Q. Have you ever engaged in the use of the INM model
-- have you yourself ever engaged in the use of the INM
model to locate or to determine the amount of noise
that has impacted, on property for purposes of eminent
domain proceedings?
A. No, I have not.
Q. Last (sic: Has) Landrum & Brown?
A. To my knowledge, no.
Q. Are you aware of any judicial proceeding where the
INM values, such as the ones shown in Exhibit 11, have
been used for the basis of the awarding eminent domain
damages?
A. I'm not aware of any.
Vigilante deposition, pages
146-47
The INM is simply a computer program. And, as one
commentator noted, the "final printout -- 'the deceptively
neat package in which the computer [displays] its work
product' -- can be a shield behind which is hidden a
multitude of programming sins. Here, as the INM's shield is
being removed, a multitude of sins are becoming quite
apparent. And those sins show that the INM is, in this
action, irrelevant, inappropriate, and inaccurate. " 37
Comment IV-1-28: Steps must be taken to validate the data
used in the computer program to verify that the results can
be calibrated by recognizable standards, especially those
established by the National Institite of Standards.
Comment IV-1-29: It is extemely important to note there
is no substantiation in the DEIS that changes in the NM
input file have been accomplished and factoed into the INM
input file used to produce the noise levels in the DEIS.
(a) Ground terrain
(b) Run-up noise
(c) Departure climbs adjusted for local elevation and
temperature
(d) Aircraft taxiing noise
(e) Existing INM Data
The Port's noise remedy programs are predicated upon decling
noise levels. This assumption is based upon noise contours
based upon these noise contour maps.
Public information request to the Port of Seattle have
disclosed INM noise modeling data used to produce the Port's
1991 and 1996 noise exposure maps. An anlysis of these
files has revoealed that many of the concerns raisedin hte
the 1981 FAA report have not been addressed.
Comment IV-1-30: At a minimum, an appendix must be added
in the DEIS which includes a complete listing of the input
file information used to produce the INM noise contours for
each of the exhibits in the DEIS. The input files should
include all of the parameters included in each input file,
including those describing ground terrain, run-up noise,
departure climbs, adjusted for local elevation and
temperature, aircraft taxiing noise.
Comment IV-1-31: Airfield layout and operational fleet
mix for each condition were drawn from data produced for the
Airport Master Plan Update. Runway utilization was
developed from Airport records and material made available
during the FAA's Capacity Enhancement Plan Update for Sea-
Tac. The detailed statistical information related to these
and other factors important to the development of the noise
contours are presented in Appendix C.
Appendix C contains a detailed description of the following:
Measurement of Noise
+ Noise footprints of aircraft types (SEL contours)
+ Historical Noise Studies at Sea-Tac
+ Noise Modeling Assumptions
+ Noise Screening of Track Chances above 3,000 feet
altitude
+ Locational Impact analysis
+ DNL levels
+ Time Above a threshold of Aweighted Sound level
+ Peak Sound Exposure Level (SEL)
+ Equivalent Sound Level (Leq)
(B) Existing Aircraft Noise Reduction Programs
The Port of Seattle was one of the first airport operators
in the U.S. to focus on ways to reduce aircraft noise
impacts on the residents surrounding its Airport. This
section summarizes the noise abatement and airport/aircraft
operation actions that have been implemented by the FAA and
the Port of Seattle. Each noise contour developed for this
Environmental Impact Statement assumes that the existing
noise abatement program will remain in effect in the future.
The program is the result of many years of continuous noise
abatement and mitigation planning efforts which have
occurred at Sea-Tac. Among these have been the Sea-Tac
Communities Plan, the original and subsequent Part 150 Noise
Compatibility Plans. and the innovative Noise Mediation
Project. These efforts have resulted in a series of long-
term and short-term measures expected to reduce aircraft
noise by at least half by the year 2001, as well as to
mitigate the effects of such noise on residences.
Existing noise abatement programs include:
Noise Budget
Nighttime Aircraft Limitations
Ground Noise Control
Flight Corridor Noise Abatement Procedures
Flight Track and Noise Monitoring
A noise budget went into effect on January 1, 1991. It sets
forth limitations on the amount of aircraft noise energy
which may be generated bv the airlines serving the Airport.
This level is gradually reduced until an allStage 3 fleet is
reached. This program and others are monitored on a
quarterly basis by the Port of Seattle Noise Abatement Staff
and reported to the public through Port publications and a
noise advisory committee.
The DEIS states that a noise budget went into effect on
January 1, 1991 which sets forth limitations on the amount
of aircraft noise energy which may be generated bv the
airlines serving the Airport. According to the program,
this level is gradually reduced until an all Stage 3 fleet
is reached. This program and others are monitored on a
quarterly basis by the Port of Seattle Noise Abatement Staff
and reported to the public through Port publications and a
noise advisory committee. Explain what portion of the
aircraft noise energy is exempted by International flights.
Also perform a colculation of the relative decrease of
annoyance according to the FICON caused by changes in the
total amount of noise energy generated by the airport since
1991.
Comment IV-1-32:
A nighttime limitations program was implemented in October.
1990, to phase-out all noisier aircraft (Stage 2) during the
nighttime hours. During the first two years, only pre-
existing Stage 2 flights were allowed between midnight and 6
a.m. In succeeding years, the restricted hours have
expanded. Bv October 1995, no Stage 2 will be allowed
between 10 p.m. and 7 a.m. without special permission.
A nighttime limitations program was implemented in October.
1990, to phase-out all noisier aircraft (Stage 2) during the
nighttime hours. During the first two years, only pre-
existing Stage 2 flights were allowed between midnight and 6
a.m. In succeeding years, the restricted hours have
expanded. Bv October 1995, no Stage 2 will be allowed
between 10 p.m. and 7 a.m. without special permission.
Explain how the exemption of international flights under the
nightime limitations program affects the communites exposed
to single event aircraft noise levels of 80 SEL and above .
Comment IV- 1-33: The so-called "Mediation Agreement" may
not be used as mitigation in Part 150 communities. The
Port's purported "Noise Mediation Agreement" between the
airport proprietor and the citizens in the noise impacted
communities both inside and outside the current DNL noise
impacted area. This agreement between the Port of Seattle
and the airlines is described most clearly, by a member who
participated as a citizen in the Port's "mediation" process. 38
As the author indicates, shortly after the Port and the
airlines agreed to its provisions , the FAA changed all
flight tracks into SeaTac, by implementing the "four-post"
plan. The program did not meet Part 150 requirements for
both process and substance, has no representative
constituency, no signatures, does not comport with the
requirements of commercial mediation, and has elicted public
renunciations by citizens. The term "agreement" is a
misnomer, insofar that there were no signatories appointed
by the respective communities to the agreement. The process
did not include consideration of iincreasing air traffic
levels at Sea-Tac from either the 4-Post routing or through
additional runways at SeaTac. The DEIS should provide a
detailed analysis, including and INM analysis with flight
tracks, fleet mix, aircraft type with engine configuration
and weights, which demonstrates how a "50% reduction in
noise" will be accomplished under the Port's "Noise
Mediation Agreement" despite a 30% increase in flight
operations.
Comment IV- 1-34:
The ground noise control program is intended to reduce both
the peak levels and duration of -ground noise events.
Although the focus of the program is to restrict noise
events during- the nighttime hours. other benefits accrue
from the measure. The measures include the prohibition of
power back operations at the gates and restrictions on
maintenance ennine run-ups at night.
The DEIS states the ground noise control program is
intended to reduce both the peak levels and duration of -
ground noise events. The DEIS further states the focus of
the program is to restrict noise events during- the
nighttime hours, and that measures include the prohibition
of power back operations at the gates and restrictions on
maintenance ennine run-ups at night. King County code
exempts aircraft noise levels completley during daylight
hours (between and 7:00 AM. Explain how this program
prohibits peak noise levels during the daytime. Explain
how the ground control noise program restricts .
Comment IV- 1-35: Flight corridor procedures are in place
which provide departure instructions to pilots of jet
aircraft to follow departure headings which place aircraft
along and either side of the extended centerlines of the
runways until reaching positions several miles to the north
or south of the Airport. During periods of low activity
(late night), the northbound Duwamish/Elliott Bay departure
procedures provide for slight turns at Boeing Field toward
Elliott Bay and Puget Sound to depart the local airspace.
During periods of high activity, runway heading is
maintained until reaching an established altitude.
The Port has installed a sophisticated flight track
monitoring, system which allows its Noise Abatement Office
to observe compliance with the noise abatement procedures.
The system has the capability to track individual flights.
The DEIS states the Port's "sophisticated flight track
monitoring system" has the capability to track individual
flights, and allows its Noise Abatement Office to observe
compliance with the noise abatement procedures. Other
airports regularly impose monetary penalties for aircraft
operators who violate noise abatement procedures. Explain
what steps the Port has taken to secure complaince. List
any incidences where the Port has levied or assessed a fine
or penalty against a pilot or airline not following noise
abatement flight corridor procedures.
The Port also maintains a permanent noise monitoring system
which provides continual noise measurements at 11 stations
located around the Airport.
The DEIS notes that the Port maintains a permanent noise
monitoring system which provides continual noise
measurements at 11 stations located around the Airport.
Further as stated above this system has not been calibrated
in accordance with WAC requirements. 39 The data collected
by the Port's noise monitoring program during periods
exceeding the annual period during which the Port's
equipment was calibrated to a recognized source is subject
to verifiication and therefore unusable for the purpose of
calibrating the INM noise contours.
Comment IV- 1-36: Chapter IV, Section @- "Land Use"
describes the Noise Remedy Program which has reduced noise
and surrounding land use incompatibilities.
Although Chapter IV, Section 2-"Land Use" describes the
Noise Remedy Program which purportedly "has reduced noise
and surrounding land use incompatibilities." several
comments are in order. The Port of Seattle's Noise
Insulation program has recently been subjected to intense
criticism. Port of Seattle employee Rick Herz who
supervises the Port's Noise Insulation program recently
testified the Port has found that the STC 35 windows
installed on homes were not adequate to meet the noise
reduction goals of the program. 40 a recent analysis by a
Citizens Watchdog Organization has raised concerns about the
effectiveness of the Noise Insulation Program. Explain when
the STC 35 windows installed on homes which have previously
undergone the Port noise insulation program will be
replaced.
Comment IV- 1-37:
(C) Area Affected by Noise
Table IV.1-1 summarizes the area within each contour range
for each altemative evaluated.
1. Existing Conditions
The aircraft noise exposure patterns for the average annual
day in 1994 is presented in Exhibit IV.1 The noise levels
represented by the contours range from 75 DNL nearest the
Airport to 60 DNL furthest from the Airport. The 60 DNL is
provided for informational purposes only to assist the
reader in better understanding the aircraft noise exposure
patterns in the community.
On the basis of scientific surveys and analysis, the FAA has
established 65 DNL as the -,critical level for the
determination of noise impacts. 41 The 65 DNL contour
incorporates 12.23 square miles (7,827 acres), including
much of Airport
property. The predominant use of southerly traffic flows at
the Airport results in a larger portion of the contour
pattern falling, south of the airfield due to the prevailing
winds. Owing to the greater thrust levels used, departures
are typically several decibels louder than approaches at the
same distance from the aircraft, resulting in larger noise
contours in the principal direction of departing traffic.
Therefore, the noise contours for the existing condition
reach farther into communities south of the Airport than
into those to the north.
The DEIS citing Federal Aviation Regulation Part 150 and the
Federal Interagency Committee on Noise (FICON) states "[o]n
the basis of scientific surveys and analysis, the FAA has
established 65 DNL as the -,critical level for the
determination of noise impacts." There is simply no
substantiation for this claim. Neither Part CFR pt. 150
or FICON make this statement. The literature is replete
with references Provide a detailed explanation of the
source of the statement "[o]n the basis of scientific
surveys and analysis, the FAA has established 65 DNL as the
-,critical level for the determination of noise impacts."
including all references to scientific litierature.
Comment IV- 1-38: The 65 DNL contour incorporates 12.23
square miles (7,827 acres), including much of Airport
property. The predominant use of southerly traffic flows at
the Airport results in a larger portion of the contour
pattern falling, south of the airfield due to the prevailing
winds. Owing to the -greater thrust levels used, departures
are typically several decibels louder than approaches at the
same distance from the aircraft, resulting in larger noise
contours in the principal direction of departing traffic.
Therefore, the noise contours for the existing condition
reach farther into communities south of the Airport than
into those to the north.
The contour shape also reflects the predominant runway usage
during north or south flow. When traffic is in south flow,
Runway 16L (the east parallel runway) is used for most
departures, while the west parallel runway (16R) is used for
most approaches. In north flow, Runway 34L is used for most
departures while Runway 34R is used for most approaches. -
The resulting pattern of existing noise exposure indicated
in Exhibit IV.1-1 clearly, shows greater noise exposure
along the centerline of the approach to Runway 16R to the
north and along the extended centerline of the approach to
Runway 34R south of the Airport. This characteristic is
further emphasized bv compliance with the Standard
Instrument Departure headings which are slightly to the left
of the extended centerline when in either north or south
traffic flow.
The 65 DNL noise exposure contour extends from its north end
over the Duwamish River, just south of the Boeing plant at
Boeing Field southward to terminate near 280th Street South.
To the east. the contour generally follows Pacific Highway
(SR 99) south of the passenger terminal complex. North of
the terminals, the contour tapers from southeast to
northwest across developed residential neighborhoods. West
of the Airport, the 65 DNL contour tapers southeasterly
across residential neighborhoods from the vicinity of 188th
Street and 8th Avenue to its southern end. It remains
generally east of and parallel to State Road 509, north of
the Airport. Directly-east and west of the runway ends, the
contour bulges outward from the Airport, reflecting the
locations at which thrust is initially applied to begin the
takeoff roll for departing aircraft. Between the runway
ends, the contour curves in toward the Airport as a result
of greater attenuation rates applied to noise dispersion for
aircraft which are on the ,around.
The 70 DNL contour reaches to between South 112th and 116th
Streets at the Rainier Golf Club on the north and nearly to
Kent-Des Moines Road on the south. It extends from 12th
Avenue on the west to the passenger terminal complex to the
east. The shape characteristics demonstrated by the 70 DNL
generally repeat those of the 65 DNL, although over a
smaller area. The area between 70 and 75 DNL contour covers
1,933 acres, including Airport property.
The 75 DNL contour remains over Airport property or public
right-of-way to the east, west and south. To -the north,
the 75 DNL extends into a residential area just north of
136th Street along the centerline approach to Runway 16R and
reaches 215th Street South along the centerline approach to
Runway 34R. The effect of noise generated bv aircraft
taxiing on taxiways is evident in the small protrusions of
the east side of the 75 DNL contour over the terminal
complex. Elsewhere, the noise levels from aircraft related
ground activity are masked by the overflight noise levels.
2. Future Impacts
The following, sections summarize the impact of the
alternatives in years 2000, 2010 and 2020. FAA Order
5050.4A, Chapter 5, Paragraph 47e (1)(d)2 states: "FAA's
threshold of significance has been determined to be a 1.5
Ldn increase in noise over any noise sensitive area located
within the 65 Ldn contour". The following sections
summarize the changes in the noise exposure contours and
identifies any 1.5 DNL (Ldn) change of noise within the 65
DNL noise exposure contours.
(a) Alternative 1 (Do-Nothing)
Aircraft noise exposure patterns for the future Do-Nothing
condition were prepared for the Nears 2000, 20 1 0, and
2020, and are shown-n in Exhibits IV.12, IV.1-3 and IV.1-4,
respectively. In each case, the noise exposure represents
projected noise levels generated bv an all Stage 3 fleet,
with average daily operations levels growing from current
946 to 1,038, 1 @ 140 and 1.280 respectively.
The noise exposure patterns for interim-cars are expected to
be less than the current impacts- In each future case. the
fleet is expected to be composed of less noisy Stage 3
aircraft (e.g.. B-757, B-737-300, and MD-80). The
operating flight characteristics (runway use, flight track
use. approach and departure procedures. etc.) now in place
are assumed to be continued with one exception. During
good weather conditions (which are predominantly north
flow). Runway 34R would be the predominant departure
runway,while Runway 34L would be the principal arrival
runway.
The level of operations in the year 1-@0'-O is expected to
sustain sufficient pressure on the capacity of Sea-Tac to
cause a small number of evening operations (4 arrivals and 3
departures on an annual average day) to be delayed into the
nighttime hours. A discussion of this affect is provided in
Appendix C. The effect during average (all-weather)
conditions is not anticipated in the earlier years
evaluated.
The land area exposed to various sound levels for each
future year are presented in Table IV.1-1. The table
indicates that within each contour range, the land area
(while less than existing conditions) increases with time
'and number of aircraft operations.
By the year 2000, the area within 65 DNL would shrink from
the existing levels to 3,910 acres, a reduction of 50
percent. The 65 DNL extends from just west of Pacific
Highway South on the east and lies along 12th Avenue to the
west. It reaches from just south of West Marginal Wav on
the north to 244th Street South @t its southern end. Its
greatest width is approximately 5,600 feet at South 188th
Street. The 70 DNL contour reaches from 128th Street South
at its northern end to 216th Street at its southern
extremity. Directly east and west of the Airport, the
contour remains over the Airport or compatibly-used
properties. The 75 DNL contour reaches from 146th Street
South southward to a point just north of 200th Street South.
The contour remains entirely on Airport property or public
right-of-way.
The noise contours for the year 2010 and 2020 Do-Nothing
alternative are only slightly larger than those of the year
2000 f)o-Nothing alternative. yet are smaller than the
existing condition. Bv the year 2010, the 65 DNL would
increase to 4, 032 acres or by 3.9 percent from the year
2000 Do-Nothing- By 2020, the 65 DNL contour would include
4,358 acres and be 11.3 percent larger than the year 2000
contour Between 2000 and 2020, the north end of the 65 DNL
contour would move northward by approximately 1,000 feet and
the south end will extend bv approximately 1,200 feet. -The
70 and 75 DNL contours would exhibit similar small increases
in their lengths over the 20 year period between 2000 and
2020. However, in no future case would the contour approach
the size of the 1994 contour.
In each future year Do-Nothing case, the presence of
aircraft ground activity is noticeable in the shape of the
75 and 70 DNL contours in the vicinity of the various
terminal facilities, but would generally be masked by flight
noise in the 60 and 65 DNL contours.
Among the sites impacted by noise in all three future years,
the predicted noise levels associated with the Central
Terminal Altemative would result in minor adjustments of
peak hour noise levels of one decibel or less in comparison
to the Do-Nothing.
(c) Alternative 3 (North Unit Terminal)
Roadway, modifications related to the new North Unit
Terminal include the development of new- access roadways to
and from the airport Expressway, and access from 176th
Street. in addition to the new northern-dnal
road%vaN-s. 156th Wav/154th Street would @e relocated north
of its existing alignment. and SR 5 18 entrance and exit
ramps NNith 24th Avenue would be construct,-d. Ile
majority of these changes are scheduled to occur after the
Near 2010. and therefore would be reflected in @e 2020
scenario. Also. the '-O-@O analysis incorporates the
proposed SR -509/South Access Road.
Changes in roadway. noise impacts for the North Terminal
Altemative are nearly- identical to those of the Central
Terminal Altemative with the exception of a few locations.
All increases in noise would be less than 1.0 dBA except
along South 170th Street. east of lnternational Blvd.. where
a peak hour Leq increase of 2.8 dBA would be experienced.
(d) Alternative 4 (South Unit Terminal)
Under @s altemative, alterations @-would be made to the
roadways @stem which relate to the development of new
temiinal structures to be located between the existing
terminal building and South 188th Street. In addition to
terminal roadway modifications, South 156th Way-/ 154th
Street would be relocated north of its existing alignment.
Also, the 2020 analysis incorporates the proposed SR
509/South Access Road. Because of the location of the new
terminal building. no critical receivers
ill be located i 500 feet of e
Within the preposed South Urlit Te@nal roadway
modifications.
In comparison to the Do-Nothing., the largest average
noise level increase associated with Alternative 4 (1.1 dBA)
would occur near the new South Access Road in Near 2020.
(3) CUMULATIVE IMPACTS
As is identified in Chapter III "Affected Environment" a
number of non-airport related developments are planned in
the airport vicinity. These actions would not likely affect
aircraft operations or aircraft fleet, Mix. There
could. however, affect surface transpor tation volumes in
the airport area. As additional surface traffic would
occur, increased roadway noise levels beyond those forecast
by- this analysis would result. However. until specific
project plans are completed for these developments, the
total cumulative impacts can not be identified. The roadway
project that is likely to have the greatest impact on noise
conditions @m the airport area is the development of a SR
509/South Airport Access Road. The impacts of
this roadway, which would not likely be available until the
year 2020 has been included in the vear 2020 Do-Nothing and
'With Project" roadway noise analysis described in the
preceding paragraphs.
(4) MITIGATION
Two key findings of the aircraft noise analysis are:
+ Future impacts will be less than the current noise
exposure regardless of which Master Plan Update altemative
is pursued-, The "With Project" alternatives would result in
slightly greater noise exposure m comparison to the Do-
Nothing.
Given the above information it is clear there is no
substantiation for the DEIS claim that "future impacts will
be less than the current noise exposure regardless of which
Master Plan Update altemative is pursued" or that "the 'With
Project' alternatives would result in slightly greater noise
exposure m comparison to the Do-Nothing." Please comment on
what approach the Final EIS will take to address these
unanswered issues.
Section 2 "Land Use" presents the population and dwelling
unit impacts associated with each of the alternatives. In
each case. the 'With Project" alternatives would result in
an increase over the "Do-.Nothing" altemative in the number
of persons and residences exposed to significant aircraft
noise.
In all cases, the properties which would be newly
incorporated into the 65DNL contour by the 'With Project"
alternatives already fall within the boundaries of one or
more of the Port's Noise Remedy Programs designed to
mitigate existing noise levels. (Not true - The program
only addresses year 2000 noise levels.) Therefore. no
additional mitigation would be needed.
Nevertheless, measures now in effect to reduce aircraft
noise within the community would be continued in an effort
to assure the minimization, to the extent practical, of
existing and future noise levels. Appendix C provides a
summary of previous noise abatement planning efforts and
programs which have been periodically conducted since the
early 1970's. The measures now m effect include:
+ Noise Budget - limiting the total noise energy carriers
may generate at the Airport until the fleet is substantially
all Stage 3.
+ Nighttime Limitations Program - limiting the hours of
operation for Stage 2 aircraft.
+ Ground Noise Control - reducing the noise of ground
events such as powerback operations and run-ups.
Flight Corridorization - maintenance of runway heading
flight tracks bv departing jets until reaching, specified
altitudes.
Flight Track and Noise Monitoring - maintenance of
records of noise levels and fligh track location information
for identification of deviations and communication with
public and users.
As none of the Master Plan Update alternatives would create
significant increased roadway noise levels, no mitigation is
needed.
The attached reports were available and well-known to the co-
authors of the DEIS and should have been addressed in the
DEIS, especially in responding to our comments above but
also in toto.
SCOPING COMMENTS
The FAA must examine the effect of aircraft noise on
newly exposed and noise-sensitive areas, as well as the
dispersion of noise over a over King County and North Pierce
County. Such areas include the following:
parks and recreation areas;
historic structures and locations,
residential communities;
schools;
health related facilities;
cultural resources;
businesses; and
houses of worship.
The noise analysis must include an examination of impacts
within the LDN, contour of 65 dB and the effect upon noise-
sensitive areas outside the LDN, contour of 65 dB. The EPA
has stated that "limiting noise analysis to the LDN 65
contours does not provide adequate disclosure of all
significant noise impacts."
Flight paths for the proposed runway likely would cause
aircraft to over fly many areas that do not currently
experience unacceptable levels of aircraft noise, thereby
subjecting new properties to the effects of airport noise.
The noise effects of the proposed third runway would be most
acute in residential neighborhoods in South Seattle,
Tukwila, Federal Way Des Moines, Normandy Park, Burien and
the North Hill communities, together with the Minority
neighborhoods in the Rainier Valley area of Seattle Many of
the potentially affected residential neighborhoods are not
included in the Port's noise mitigation program (which
provides for installation in residences of sound insulation
materials). Even residences that are eligible for the
Port's sound insulation program would obtain relief only
from high interior noise levels. High outdoor noise levels
would continue to erode the enjoyment of property and the
quality of life in these and other communities.
The third runway proposal also would increase noise levels
in area schools. The Port's most recent noise exposure map
indicates that a large number of schools currently are
located within the 65 LDN contour for 65, 70 or 75 dB.42
Interior single event noise levels in excess of 85 dB have
been measured in at least one school district.43 With
approximately 6,000 students enrolled in schools within a
few miles of Sea Tac, increased aircraft operations and
altered flight paths would harm the quality of education in
local schools.
Current operations at SeaTac subject many other noise
sensitive resources -- such as hospitals, nursing homes and
churches to average noise levels of 65 dB or greater.44 The
Port has estimated that the number of noise sensitive areas
exposed to LDN in excess of 65 dB would decline by 1996, a
prediction upon which cities and residents have relied. The
construction and operation of a third runway at Sea Tac,
however, likely would prevent a number of hospitals, nursing
homes and churches near Sea Tac from realizing significant
reductions in their noise exposure levels. Moreover, many
locations could be expected to be exposed to even higher
numbers of over flights and to greater noise levels than
they experience today.
The E.I.S. must investigate and fully disclose studies of
existing conditions, including actual measurement of
existing noise levels. The Flightplan E.I.S. used only the
heavily criticized and recently revised theoretical "INM"
computer generated noise model, and did not document any of
the assumptions (such as fleet mix) in constructing the
model. Further, noise impacts missing from the model, such
as all ground noise (from "runups" and airport ground
activities), noise from aircraft from foreign carriers and
others exempt from Stage III requirements, weight and flight
profiles appropriate to Sea-Tac, land & atmospheric effects
at Sea-TAC etc. were not included. All sources of noise
must be fully disclosed and raw measurement data and
assumptions used must be included. All sources of
assumptions must be fully documented and properly cited per
our earlier comment.
The E.I.S. must investigate and fully disclose all impacts
of noise to human health and to the education of children.
We specifically reference Hansen & Sanders report titled The
Adverse Health Impacts of Airport Expansion with Particular
Reference to Sea-Tac International Airport. previously
submitted.
Techniques for measuring noise are called "metrics."
Because no one metric can measure noise and because noise
studies use a variety of metrics, existing and projected
noise levels must be displayed in--at minimum--the following
metrics:
1) Maximum decibels (both A & C weighting) plus the number
of events. Maximum decibels should include values for each
aircraft in the fleet mix, including heavy jets and must be
displayed for any aircraft, such as foreign carriers, exempt
from Stage III, as well as ground noise.
This metric defines the loudness of the noise and the number
of noise intrusions. Maximum decibels are the most widely
used measurement of noise and are required to compare noise
levels to most studies linking noise to hearing loss, to
measure construction and insulation standards and as well as
establishing maximum levels required by hospitals and other
noise sensitive structures and areas. The E.I.S. should
show maximum noise levels down to 35 dBA and identify all
noise sensitive structures in that area.
2) SEL (Single Event Level), including all SEL (both A & C
weighted) above 50 in increments of 5 plus the number of
events. Maximum decibels should include values for each
aircraft in the fleet mix, including heavy jets and must be
displayed for any aircraft, such as foreign carriers, exempt
from Stage III, as well as ground noise. The method for
calculating the noise including the assumed event length
must be documented along with the rationale and a fully
cited bibliography justifying those assumptions.
This metric represents not only the loudness of the noise
but the length of time the noise lasts. It is used in most
sleep disturbance and school disruption studies, most
particularly the N.A.S.A. sleep disturbance studies.
3) Ldn (both A & C weighted) above 45 Ldn at 5 decibel
intervals and the and CNEL(Combined Noise Event Level)
equivalent. The Ldn must include ground noise and document
the assumptions about aircraft fleets.
Both of these metrics--although much in dispute- for the
measurement of aircraft noise--attempt to average noise on
24 hour basis and then on an annual basis. They have been
used to define the 65 LDN area subject to Part 150
requirements and for EPA standards at 55 Ldn, and are used
in studies documenting blood pressure, heart disease, and
mental illness.
4) Unmeasurable, but annoying noise. The impact statement
should identify noises which, like finger nails on a
blackboard, have unwanted impacts and to display them. High
scream noises, back up whistles for airport loaders, etc.
would fall in this category.
The LDN metric obscures the true noise impacts and does
not provide any useful information about the level of noise
attributable to individual over flights. The effect of
noise upon a number of noise-sensitive areas in the vicinity
of Sea-Tac cannot be described adequately or analyzed solely
using the LDN metric. Activities that take place primarily
during the day or in the early evening when the number of
Airport operations are at their peak can not be represented
accurately by an LDN contour. Therefore, the impact of
noise on citizens, public schools, on health care and
retirement facilities, or on the normal business activities
of commercial establishments cannot be evaluated through the
exclusive use of the LDN metric. A number of different
noise metrics must be used to examine the effects on these
noise-sensitive institutions and activities.
All noise studies and projections should include ground
noise, runups and maintenance operations. Runups, in
particular, produce high decibel noise (over a hundred
decibels) lasting many minutes and can be heard over four
miles from the airport.
All noise measurements and projections must be given in
both the A-filter frequency and the C-filter frequency. C-
filter frequency identifies low rumble noise sources such as
made by many jet engines. Noise at these frequencies are
more penetrating--like the baseline on the neighbor's stereo-
-and therefore must be given.
The "Noise Remedy Program" may not be used as mitigation in
Part 150 communities. This program was offered as
mitigation in 1976 for noise created by the second runway,
is incomplete and a source of controversy--including a
lawsuit. Completing previously promised mitigation cannot
be used as mitigation for new noise created by 30% more
operations.
_______________________________
1 Dr. Sanford Fidell, Expert Arbitration Panel, May 5,
1995, pg. 75, line 6
2 Dr. Sanford Fidell, Expert Arbitration Panel, May 5,
1995, pg. 74, line 14
3 Dr. Sanford Fidell, Expert Arbitration Panel, May 5,
1995, pg. 75, line 9
4 See attached Appendix #1--Aircraft Noise Coalition Press
Release dated March 24, 1993
5 See Report to the Administrative Conference of the U.S.,
Suter, Alice. 1990.
6 Favro et al v. Port of Seattle, Second Amended Compaint
for Violation of Constitutional Rights and Trespass, U.S.
District Court No C92-C1634 , pg. 4
7 Letter from Richard E. Sanderson, Director, Office of
Fed. Activities, U.S. Envt'l. Protection Agency, to Office
of the Chief Counsel, Fed. Aviation Admin. (Jan. 18, 1989)
.
8 Order on Phase 1 Noise Issues issued January 9, 1995, pp.
3-4
9 Ibid, pg. 2
10 Vigilante deposition, Exhibit No. 22 (emphasis added)
11 In point of fact, measurements taken by Chicago at a
variety of schools scheduled for soundprooflixg show that
the attenuation between the exterior and interior of the
schools can be considerably less than 15 decibels -- e.g.
less than 5 decibels attenuation. See School Noise
Monitoring Analysis (July-September 1991) (Hamill
deposition, E@bit 6). Ms lack of attenuation means that
exterior levels less than 65 dBA can have a-n adverse impact
on speech communication in the classroom, since the level
for interference is considered by Vigilante to be 45 dBA.
12 These schools are Medinah South, Lake Park East
(partially soundproofed entirely at owners expense), Lake
Park West, Edison, Emerson, Field, Sandburg, and
Churchville.
13 Expert Arbitration Panel, May 4, pg. 68, line 14)
14 Implementation of an LDA/DME Approach to Runway 16R in
Lieu of a Third Runway at SeaTac Airport prepared by G.
Bogan & Associates Inc. June 26, 1995
15 1993 Aviation System Capacity Plan Report DOT/FAA/ASC-93-
1 Appendix C-53
16 SeaTac Forum December 1994
17 Comments of Noise Aspects of the Regional Airport System
Plan by Dr. James D. Chalupnik January 12, 1993 pg. 1
18 FAA Advisory Circular 36-1F Noise Levels for U.S.
Certificated and Foreign Aircraft, June 5, 1992, pp.16-18
19 Ibid, Appendix 3, pg. 4
20 Ibid, Appendix 1, pg. 5
21 Order on Phase 1 Noise Issues issued January 9, 1995, pg.
2
22 Interim Technical Addendum Regarding the city of
Chicago's Use of the Integrated Noise Model State of
Chicago ex. rel. Ryan vs. City of Chicago 18th Judicial
District Court Dupage County, Illinois, pg. 9
23 Ibid. pg. 11
24 Expert Arbitration Panel, May 5, 1995, pg. 137, line 6
25 Expert Arbitration Panel, May 5, 1995, pg. 136, line 10
26 Expert Arbitration Panel, May 5, 1995, pg. 137, line 12
27 A Comparison of FAA Integrated Noise Model Flight
Profiles with Profiles Observed at Seattle-=Tacoma by George
W. Flathers, II December 1981 Report No. FAA-EE-82-10
28 Ibid. pg. vii
29 Ibid.
30 Ibid.
31 Ibid. pg. x
32 Ibid. pg. viii
33 Ibid. pg. x
34 Ibid.
35 Flathers, FAA Integrated Noise Model Validation: Analysis
of Air Carrier Flyovers at Seattle- Tacoma Airport, FAA
Report FAA-EE-82-19 (September 1982) pp. v
36 Ibid, pg. vi
37 Interim Technical Addendum Regarding the city of
Chicago's Use of the Integrated Noise Model State of
Chicago ex. rel. Ryan vs. City of Chicago 18th Judicial
District Court Dupage County, Illinois, pg. 9
citing Elliot, Computer-Nourished Experts: An Evidentiary
and Procedural Perspective, 43 Brooklyn L. Rev. 1119,1132
(footnote omitted).
38
39 Letter to Expert Panel dated May 1995 from the Pork
Patrol
40 Expert Arbitration Panel May 5, 1995, page 66, line 9
41 Federal Aviation Regulation Part 150 and the Federal
Interagency Committee on Noise
42 Sea-Tac International Airport, Noise Exposure Map Update
(Draft) (i 991) App. D ('l 991 NEM Update)
43 RCAA, James C. Chulupnik, Noise from Sea-Tac Airport:
Adverse Affects on the Heath of Puget Sound Citizens (Jan.
26, 1993) at 2.
44 1991 NEM Update at D-10, Table D-3. Order 5050.4A 11 85&