&EPA
              United States
              Environmental Protection
              Agency
             Region 5 Noise Program
             230 South Dearborn Stree:
             Chicago, Illinois 60604
905R81113
The Review Of Residential,
Commercial, And Industrial Project
Related Environmental Impact
Statements For Noise Concerns:
A Brief Outline And Checksheet

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    THE REVIEW OF RESIDENTIAL, COMMERCIAL,  AND
INDUSTRIAL PROJECT ENVIRONMENTAL IMPACT STATEMENTS
FOR NOISE CONCERNS:  A BRIEF OUTLINE AND CHECKSHEET
                    By
              Gale R. Hruska
         Noise Control Specialist
   U.S. Environmental Protection Agency
        230 South Dearborn Street
         Chicago, Illinois  60604

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                                   PREFACE

Many projects, especially those involving Federal  actions  or Federal  funding,
require the submission of environmental impact statements  (EIS's).   To  assist
the people responsible for EIS preparation, many useful  sources  of  information
have been developed.  However, almost no attention has been given to assisting
the person who has to review one.  It seems to be implied  that the  same
material used in the preparation of the document is adequate for its review.
Unfortunately, as people who have had to review EIS's know, this is not
quite the case.  The different perspectives of the preparer and  the reviewer
require that they approach the EIS from different directions.  The  EIS  pre-
parer strives to include sufficient information to provide a complete de-
scription of the noise impact of the project, while the reviewer must be
able to ask the right questions to pinpoint any inadequacies.

In response to requests from both professional EIS reviewers and the public,
the Region V Noise Program has assembled a list of concerns that it feels
every EIS should address.  This particular document is concerned with non-
transportation related projects.  It is our hope that, in  spite  of  its
brevity, it will be a basis from which a competent noise review  can be  effected.

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                                   CONTENTS





INTRODUCTION                                                       Al  - A2



CHECKSHEET                                                         81  - B8



COMMENTARY ON CHECKSHEET CONCERNS                                  Cl  - C12



REFERENCES                                                         Dl

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                                 INTRODUCTION

Anyone who reviews Environmental Impact Statements (EIS)  for  noise
considerations is certain to discover that there is no single set of  questions
that can be used to judge EIS adequacy.  The reasoning behind this  conclusion
is that each project (and the environment that the project  either impacts or
is impacted by) is unique.  What is a major concern for one project can  often
have minimal impact on another.  However, this is not to say  that there  is  no
systematic way to evaluate an EIS.
After reviewing many EIS's for noise impact, the Region V Noise Program  has
come to feel that there are five basic areas in which an EIS  should provide
information:
     1.  Site description
     2.  Project description
     3.  Existing and future noise levels
     4.  Noise impact caused by the project (or to the project)
     5.  Mitigation measures necessary to reduce noise impact to
         acceptable levels
To assist the reviewer on determining whether or not a non-transportation
related EIS has adequately addressed these concerns, an EIS Review  Checksheet
has been prepared.  The purpose of this exercise is not to set standards, but
only to provide a systematic list of concerns that the well prepared  EIS will
address.  Therefore, there is no discussion of quantitative aspects of environ-
mental review.  There are no tables, graphs, or equations for predicting how
much noise will be produced or how serious the noise impact will be.    If
the reviewer wants to corroborate this type of information, he will have to
go to the other sources, such as those given in the references,

                                     A-l

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The checksheet consists of six major questions relevant to the adequacy  of
the noise portion of the EIS.  Associated with each question are a number of
minor aspects which can be used to determine if the question is adequately
addressed.  It is suggested that the reviewer checkoff the minor aspects as
he encounters them in the EIS.  Those that are poorly discussed should be
noted.  For those aspects that are not discussed at all, the reviewer should
determine if they are relevant to the particular project.  Those that are  not
discussed but are relevant should be noted.  After the adequacies and
inadequacies of all of the minor aspects have been examined, the reviewer
then uses the accumulated findings to determine how well he feels the major
question has been answered, i.e.  Has the EIS addressed the question
adequately, adequately with reservations, or not adequately?
Those who are not familiar with environmental noise assessment may find the
checksheet rather terse.  For these people, a brief commentary dealing with
each of the six basic questions has been included.  Should one want to probe
deeper into this subject, he must go the literature.
                                         A-2

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RESIDENTIAL, COMMERCIAL. AND INDUSTRIAL PROJECT EIS REVIEW CHECKSHEET

Project 	
Date    	
(Note:  If the project is primarily a noise receiver, go to Section A.
        If the project is primarily a noise generator, go to Section B.

SECTION A - NOISE SENSITIVE PROJECTS
1.  IS THE SCOPE OF THE PROJECT ADEQUATELY DESCRIBED?
    [  ] Adequate    [  ] Adequate with reservations     [  ] Not  adequate
    [  ] Physical description of site
         [  ] Buildings, main use areas
         [  ] Remainder of site grounds
    [  ] Site usage
         [  ] Population involved:  number of people, pertinent  characteristics
         [  ] Hours of use
     [  ] Ultimate development plans
     [  ] Alternatives
2.  IS AN ADEQUATE VISUAL DESCRIPTION OF THE SITE AND ITS ENVIRONMENT  PROVIDED?
    [  ] Adequate      [  ]  Adequate with reservations     [  ] Not adequate
    [  ] Type of visual overview
         [  ] Aerial photograph
         [  ] Drawn schematics
         [  ] Other
         [  ] None
     [  ] Adequate map scale:  explicitly identified, reasonable size
     [  ] Project buildings and boundaries superimposed on site  map
                                      Bl

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    [  ] Existing potential  noise sources located  and  identified
         [  ] Roads and highways
         [  ] Railroad tracks and yards
         [  ] Airports and flight path tracks
         [  ] Recreational activities (parks,  boating,  race  tracks, etc.)
         [  ] Industrial  noise sources
         [  ] Commercial  noise sources
         [  ] Other
    [  ] Future developments located and identified
3.  IS ADEQUATE QUALITATIVE AND QUANTITATIVE  DATA  ABOUT THE  POTENTIAL NOISE
    SOURCES PROVIDED?
    [  ] Adequate        [  ]  Adequate with  reservations     [  ] Not adequate
    [  ] Roads:        distances to site, traffic  volumes, car-truck mix,
                       speed limits
    [  ] Railroads:    distances to site, day-night  operations mix, train lengths,
                        switching operations,  parking  of idling locomotives and
                        refrigerator cars
    [  ] Airports:       traffic volumes, distances to  site,  jet-nonjet mix,
                        day-night mix, flight  path descriptions, distance to
                        site
    [  ] Recreational:  usage patterns,  distances  to site
    [  3 Industrial:    types of noise producing  equipment, locations of equipment,
                       distances to site, loading  dock  locations, parking
                       locations, hours  of operation
    [  ] Commercial:    Noise sources, distances  to site, loading dock locations,
                       hours of operation
    [  ] Other
                                      B2

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4.  ARE ADEQUATE QUANTITATIVE NOISE PREDICTIONS PROVIDED?
    [  ] Adequate     [  ] Adequate with reservations      [  ] Not  adequate
    [  ] Noise descriptors used
         [  ] Day-night equivalent sound level  L(dn)
         [  ] Hourly equivalent sound level Leq(h)
         [  ] Maximum A-Weighted levels L max
         [  ] Other
    [  ] Predicted Noise levels at site provided
         [  ] Noise levels from individual sources
         [  ] Overall noise levels
    [  ] Ambient noise measurements provided
         [  ] Adequate times of day
         [  ] Adequate duration of measurements
    [  3 Predicted and measured noise levels agree with reviewer's corroborating
         calculations
5.  IS THE NOISE IMPACT ADEQUATELY DISCUSSED?
    [  ] Adequate   [  ]  Adequate with reservations  [  3 Not adequate
    [  ] Discussion of noise measures and their relation to impact
         [  3 Definitions
         [  3 Explanation of the relations between noise levels and degrees
              of hearing loss and annoyance
    [  3 Discussion of degree of impact on project
         [  3 Number of people affected at various noise levels
         [  3 Impact from individual  sources
         [  3 Combined impact from all  sources
                                     B-3

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  6.  ARE MITIGATION MEASURES ADEQUATELY CONSIDERED?
      [  ] Adequate  [  ] Adequate with reservations  [  ] Not  adequate
      [  ] Explicit documentation with regard to the need (or no need) for  noise
           Mitigation measures
      [  ] Specific mitigation measures considered
      [  3 Barriers or earth berms
      [  3 Restrictions on the locations of noise ssensitive activities
      [  3 Construction design measures:  insulation, sealed windows,  etc.
      [  3 Other
[  3  Commitment to use of mitigation measures (if needed)

  SECTION B - NOISE GENERATING PROJECTS
  1.  IS THE SCOPE TO THE PROJECT ADEQUATELY DESCRIBED?
      [  3 Adequate  [  3 Adequate with reservations  [  3 Not  adequate
      [  3 Physical parameters relating to the project
           [  3 Building construction:  site layout, type of construction,  etc.
           [  3 Delineation of potential noise sources
           [  3 Description of parking facilities
           [  3 Description of truck routes and railroad tracks associated  with
                facility
           [  3 Description of loading and unloading areas
      [  3 Number of people involved at site and number of motor vehicles
           expected
      [  3 Projected hours of operation of site
      [  3 Ultimate development plans of project
      [  3 Alternatives to proposed project
      [  3 Construction activites
                                       B-4

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2.  IS AN ADEQUATE VISUAL DESCRIPTION OF THE SITE AND ITS SURROUNDING ENVIRONMENT
    PROVIDED?
    [  ] Adequate   [  ] Adequate with reservations   [  ] Not adequate
    [  ] Type of visual description
         [  ] Aerial photographs
         [  ] Drawn schematics
         [  ] Other
    [  ] Map scale adequate:  reasonable size, explicitly given
    [  ] Project site
         [  ] Site boundaries located and identified
         [  ] Individual noise sources located and identified
         [  ] Parking areas located
         [  ] Loading-unloading areas located
    [  ] Surrounding area exected to be impacted by the project
         [  ] Location of noise sensitive activities (school, parks, churches,
              residences, etc.
         [  ] Location of roads impacted by traffic to and from project
         [  ] Location of land affected by site related railroad tracks and
              yards
    [  ]  Zoning and land-use profiles of land surrounding project identified
3.  IS ADEQUATE QUALITATIVE AND QUANTITATIVE DATA ABOUT THE POTENTIAL NOISE
    SOURCES PROVIDED?
    [  ] Adequate  [ ] Adequate with reservations  [  ] Not adequate
    [  ] Information on specific noise and vibration generators provided
         [  ] Distances to boundary lines and affected noise sensitive sites
         [  ] Expected hours of operation
                                     B-5

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         [  J Typical noise levels produced by noise sources (including
              sources of information)
    [  ] Roads and highways:  distances to residential  and noise sensitive
          sites, traffic volumes before and after construction, car-truck
          mix before and after project
    [  ] Parking lots:  locations, usage patterns, capacities, distances
         to affected sites
    [  ] Truck loading facilities:  locations, day-night usage patterns,
         traffic volumes, types of vehicles, idling vehicle and
         refrigeration unit areas
    f  ] Railroad facilities:  freight volumes, day-night operations
         usage, idling locomotive and refrigerator car areas, switching  areas
    [  ] Construction activities:  types noise sources, duration of
         construction phase of project, night operations
    [  ] Other
4.  ARE ADEQUATE QUALITATIVE NOISE PREDICTIONS PROVIDED?
    [  ] Adequate   [  ] Adequate with reservations  [  ] Not adequate
         [  ] Noise descriptors used
              [  ] Day-night equivalent sound level L(dn)
              [  ] Hourly equivalent sound level Leq(h)
              [  3 Maximum sound level L max
                   [  ] A-Weighted (dBA)
                   [  ] Octave bands (dB)
              [  ] Other
                                     B-6

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         [  ] Noise level  predictions provided for individual  noise  sensitive


              sites


              [  ] Before project


              [  ] After project - from individual  sources
    y,

              [  ] after project - overall  level


              [  ] Construction noise levels


         [  ] Noise level  predictions provided at project boundary lines


              [  ] Before project


              [  ] After project - from individual  sources


              [  ] After project - overall  level


         [  ] Ambient noise measurements provided


              [  ] At site boundaries


              [  ] At individual noise sensitive sites


              [  ] Taken at representative times of day


              [  ] Taken for adequate lengths of time




         [  ] Predicted and measured noise levels agree with reviewer's


              corroborating calculations


         [  ] Vibration problems considered


5.  IS THE NOISE IMPACT ADEQUATELY DISCUSSED?


    [   ] Adequate  [  ] Adequate with reservations  [  ] Not adequate


         [  ] Discussion of noise measures and their relation to impact


              [  ] Definitions


              [  ] Explanation of the relations between noise levels and


                   degrees of hearing loss and annoyance


         [  ] Discussion of impact on population:  number affected,  degree of


              impact


                                      B-7

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          [  ] From individual noise sources
          [  ] From combined overall impact
          [  ] At individual noise sensitive sites
          [  ] At project boundary lines
     [  ] Construction noise impact discussed
     [  ] Vibration impact discussed
     [  ] Comments from public and other governmental  agencies included
          and discussed

ARE MITIGATION MEASURES ADEQUATELY CONSIDERED?
[  ]  Adequate  [  ] Adequate with reservations  [  ] Not adequate
       [  ] Explicit documentation with regard to the need (or no need)  for
            mitigation measures
       [  ] Specific measures considered
            [  ] Project design considerations: quieted equipment, sealed
                 windows, noise insensitive locations, etc.
            [  ] Noise barriers or berms
            [  ] Land use restrictions
            [  ] Time use restrictions
            [  ] Other
      [  ] Commitment to use of mitigation measures where needed
                                 B-8

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BRIEF COMMENTARY  ON  CHECKSHEET CONCERNS
Site specific construction  projects can usually be partitioned into two classes
relative to  noise considerations.  In the first class, there are those projects
that are treated  as  noise receivers.  This would include housing developments,
schools, hospitals,  apartment complexes, etc.  The second catagory comprises
those projects that  are  basically  noise producers, examples of which are shopping
centers, industrial  parks,  military facilities, and race tracks.  The main
concerns for the  two projects classes turn out to be nearly the same; however
i'.htf questions that must  be  answered to ascertain adequacy are often quite
different.   For this reason we have prepared a checksheet for each of the
project types in  which the  main questions are identical but the supporting
data required may be quite  different.

1,  IS THE SCOPE  OF  THE  PROJECT ADEQUATELY DESCRIBED?
NOISE SENSITIVE PROJECTS:   In most EIS's, the physical description of the
proposed project  is  adequately described.  The reviewer should focus on those
project aspects that will help to minimize noise problems as well as those
that could exacerbate the problems caused by noise intrusion from the
surroundings.  For example, if a residential development is backed up against
a freeway, it is  a bad situation an it should be noted.  However, if there is
a hill  that  shields  the  complex from the highway noise the situation is now
good and this fact should be noted.

The EIS should provide data on site usage. How many people will be involved
with the facility?   Are  any special noise sensitive groups, such as children,
the elderly, hospital patients, etc., expected, to utilize the facility?  At
what times will  it be in use?
                                     C-l

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Information should be provided as to what is anticipated as  the  ultimate
development of the project.  The reviewer should investigate the possibility
that while the proposed project might meet acceptable noise  criteria,  subsequent
development might not.  We have seen EIS's where developers  have acknowledged
the existence of noise problems on one segment of a project, but asked for  a
variance on noise requirements because an earlier portion of the project  had
already been completed.  The reviewer should also consider the possibility  of
future off-site development which would cause the site to be impacted. The
presence of large undeveloped tracts of land near the site of a  housing
project is an example of a situation which would give cause  for  concern,
especially if the land was zoned other than residential.

NOISE GENERATING PROJECTS  The project that generates noise  as a by-product
of its operations needs to be looked at as a collection of individual  noise
sources which add together to produce an overall impact.  Its description
should be complete enough so that it will be evident to the  reviewer where
and from what sources noise problems are likely to surface.   In  addition  to
particulars about the main use activities of the facility, attention must
also be given to noise sources that are associated with supporting  operations,
such as parking facilities, truck routes, railroad tracks, and loading docks.
A complete description of the scope of the project includes  estimates of  the
number of people involved at the facility, the amount of motor vehicle traffic
expected to be generated as a result of the facility, and the hours the
facility will be in operation.  If alternate development plans are  under
consideration, a description of how they differ from the preferred  alternative
should be clearly presented.
                                     C-2

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Construction noise can often be a serious temporary problem.   The EIS  should
provide a description of construction schedules, types of equipment  to be
used, and hauling routes.  Finally, there should be a definite statement
regarding the ultimate development plans for the project.  The reviewer should
examine the possibility of a scenario where the proposed project meets
acceptable noise criteria, but a future expansion may not.   Large vacant
areas on the site map should cause one to consider this concern.
2.  IS AN ADEQUATE VISUAL DESCRIPTION OF THE SITE AND ITS ENVIRONMENT  PROVIDED?
An EIS should provide an overview of the site and its environment.   A  pictorial
representation seems to be the best choice to meet this need.   It should be
of sufficient scale and clarity to provide unambiguous information about the
concerns listed in the checksheet.  It will be used in corroborating the EIS
noise predictions and in pinpointing areas where noise problems could  surface.
Although blueprints an other drawn graphics can provide much needed  information,
the aerial photograph is by far the most useful tool.  It allows the reviewer
an independent look at the site area.  There have been many instances  where
the study of an aerial photograph has located potential noise problems that
were not discussed in the EIS.  Close scrutiny of this photograph should
always be made if it is provided.
NOISE SENSITIVE PROJECTS  For this situation, the most useful  method of
visualization would be to have a ground plan of the project structures and
the site boundary lines superimposed over a map of the area.   Noise  sources
that could potentially affect the project would be identified and a  map
scale would be included so that distances from the noise sources to  the
project could be determined.
                                     C-3

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NOISE GENERATING PROJECTS  For this type of project, a site plan (to scale)
having the locations of noise sources identified is needed.  Additionally,
the property boundary lines should be superimposed on the overall  area  map.
The noise sensitive activities that could be affected by the project should
also be identified.  This information is needed to locate the noise sources
relatfve to the noise affected areas in order that calculations of noise
impact can be made.  Vacant land within the project boundaries can also be
identified by the reviewer as to its potential  for future development.

3.  IS ADEQUATE QUALITATIVE AND QUANTITATIVE DATA ABOUT THE POTENTIAL NOISE
SOURCES PROVIDED?
NOISE SENSITIVE PROJECTS  The EIS should supply sufficient data so that all
of the potential noise sources in the vicinity of the project are  described
in enough detail to allow the reviewer to make his own calculations of  noise
levels.  The particular information requested in this question should be
sufficient for him to make corroborating calculations using the methods given
in the references.

Construction noise problems are rare in this type of project.  However, if
the project is large enough, the reviewer may feel that the same type of
information that is asked for in the next section is applicable here*

NOISE GENERATING PROJECTS  In this situation the EIS needs to be concerned
with three categories of noise generation:   facility operations, transportation
noise associated with the facility, and construction noise.
                                     C-4

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The noise from facility operations is often hard to characterize  prior  to
construction because of the wide variety of often exotic noise sources  that
may be present.  However, many manufacturers, especially those involved with
air handling and conditioning equipment, provide noise specifications for
their "products.  This information should be included in the EIS when it is
available.  Where octave band noise levels are given, they may easily be
converted into the A-weighted noise levels that are used to assess  impact.
The sources of the  noise levels information should be provided so  that the
reviewer can verify any noise levels that appear to be unreasonable.
Estimates of the noise expected from untested equipment may be included in
the EIS even though the degree of uncertainty in their true levels  may  be
significant.  A "best estimate" is better than no information at  all; it
will at least give the reviewer a "ball park value" as to what noise levels
to expect.

Hours of operation of the facility are needed to estimate noise impact  and
should be included in the EIS.  In certain situations, such as with drop-
forge or punch-press facilities, ground transmitted vibrations can  cause
problems.  The EIS should address this problem if it is applicable.  Fortunately,
the effects of vibration usually can be expected to die out very  quickly  as
the distance from the source to the receiver is increased.  Thus, most
vibration sources will affect only those sites very near to the source, and
will only pose problems to the surrounding community when they are  located
close to the property lines.
                                     C-5

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Railroad and motor vehicle traffic in and out of the facility can cause  a
significant noise problem, especially if the tracks or roads  pass through
residential areas.  Information sufficiently detailed to allow estimates of
this impact should be provided.
Construction activities can cause temporary noise problems.   The most  common
complaints are those from truck hauling, earth moving equipment, and pile
driving operations.  It is especially important that hauling  truck routes  be
identified, along with the expected traffic volumes, when residential
development is located near the site.
4.  ARE ADEQUATE QUANTITATIVE NOISE LEVEL PREDICTIONS PROVIDED?
Noise level predictions are usually given in one of three metrics:  the
maximum A-Weighted sound level (dBA), the hourly equivalent  sound level
Leq(h), or the equivalent day-night sound level L(dn).  The  A-Weighted should
level provides a measure of the instantaneous volume of a sound as it  would
be perceived by the human ear.  The maximum A-Weighted level  gives the loudest
level that occurred during some particular period of time.   A-Weighted levels
can be used to characterize impact in situations where the sound is either of
very short duration, or is a single event.  However, if the  noise level
fluctuates over longer periods of time, an averaged sound level will correlate
better with degree of impact.  The hourly equivalent sound level is an energy-
averaged sound level over a one hour period,  L(dn) is similar to Leq(h) in
that it is also an energy-averaged sound level.  However, in this case the
sound energy is averaged over a 24 hour period, with a 10 decibel penalty
added to all noise ocurring between the normal sleeping hours of 10 p.m. to
7 a.m.  U.S. Environmental Protection Agency has correlated  annoyance  and
hearing loss to L(dn) values, which makes this metric useful  in assessing
noise impact.
                                     C-6

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How should noise levels be presented?  When a wide impact  is  expected,  noise
contours can be superimposed on a site map.  A noise contour  is  a  line,
together with a sound level, such that the land enclosed by the  contour can be
expected to experience noise levels as great or greater than  the given  sound
level.  It is analogous to a topographic map where points  at  a specific height
are connected together to make an equal height contour, only  in  this  case  it
is equal noise level points that are connected.  If only a small area or only
a few sites are affected, it is sufficient that a listing  of  sound levels  be
orovided at representative points.
NOISE SENSITIVE PROJECTS  Noise levels produced by the various noise  sources
can either be calculated or measured.  If the levels are calculated,  the EIS
should provide, in addition to the overall level, the relative contributions
of each noise source.  This information is useful in determining where  the
major problems originate.  Also, if the results of the reviewer's  corroborating
calculations disagree with the EIS values, the reviewer can pinpoint  which
source levels are in question.
Measurements of existing noise levels can be substituted for  calculations  in
this situation, since the same noise sources affect the site  both  before and
after project completion.  The measurements should be taken at representative
times of day and for long enough periods of time so as to obtain an accurate
estimate of the noise environment.  The reviewer should also  be sure that
measurements were taken during those times when the major noise sources were
operating and producing maximum noise levels.
                                     C-7

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NOISE GENERATING PROJECTS  In this type of project it is esspecially  important
to have noise predictions (or measurements) for the site prior to construction
as well as for the period after the project is completed.   The reason for  this
requirement is that the severity of noise impact is stongly dependent on what
noise levels the people in the area are acclimated to.

Noise levels should be provided at the lot lines of the site as well  as at
the locations of individual  noise sensitive activities.  The lot line values
are important in areas where vacant land borders the project site.   They will
permit a city to zone the vacant land so that future projects will  be compatible
with the noise from the present project.

It is much more difficult to accurately predict vibration levels than it  is
to predict airborne noise levels.  For this reason we do not normally expect
an EIS to provide quantitative vibration levels.   However, we do expect  at
least a qualitative discussion of the problem.  Is there machinery at the  site
capable of causing a major vibration impact?  If so, does the EIS expect  the
vibrations to be great enough to be perceived by a person located at  the
property line or at one of the noise sensitive sites?  If the answers to
these questions are strongly affirmative , it may be necessary to require
quantitative data.

Construction noise levels should be included if there is any likelihood of
impact.  This data can be obtained by actual measurement or it can be estimated
by consulting the literature.  Remember that truck hauling noise can affect
people large distances from the site, so that expected  levels along hauling
routes should be included if this is a major activity.
                                     C-8

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5.  IS THE NOISE IMPACT ADEQUATELY DISCUSSED?
A discussion of noise impact involves more than simply providing  noise  levels.
The EIS should discuss how the noise measures used in the EIS relate to
hearing loss and annoyance.  General relations between noise levels  and the
degree of impact on people (e.g. noise levels vs percent of people annoyed)
can be obtained from the literature and should be included.  The  annoyance
aspects are most important since there are very few sites at which operations
will be so loud as to cause physical hearing damage.

It should be noted that "the degree of impact" is a relative concept.   If
ambient noise levels are low to begin with, the impact of a project  could be
significant in spite of the fact that the new noise levels might  not exceed
normal standards.  For example, consider a factory built in a rural  area
which originally experiences L(dn) noise levels in the 40 decibel  range. If
the post-project levels turn out to be 10 dB greater, they would  still  be
acceptable for most residential areas.  To the people living in the area,
however, the new levels would be subjectively twice as loud as they  originally
were.
For our considerations of noise impact, we generally feel that outdoor  L(dn)
levels of 55dB or less are quite reasonable in residential areas,  while
levels above 65-70dB are definitely excessive.  In term of identifiable
changes in impact, a 3-4 dB increase in L(dn) is noticeable, while increases
greater than 7-8 dB are considered major.

Good sources for locating potential noise problems are letters from the public
and from governmental agencies.  They are usually printed in an appendix
associated with public comments.  The EIS should provide specific  replies to
their concerns.
                                     C-9

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NOISE SENSITIVE PROJECTS  The reviewer must verify that the EIS relates  the
noise levels expected at the site to the requirements of the project,  since
site usage plays an important part in determining what noise levels  are
acceptable.  For example, a convalescent home would require a quieter
environment than could be tolerated by a housing development.  The EIS should
provide an analysis as to what degree the people at the site will  be affected
relative to these suggested maximum levels.
NOISE GENERATING PROJECTS  The EIS should detail the impact on those noise
and vibration sensitive sites affected by the project.  Given the  calculated
noise and vibration levels, what will be their effect on the populace?  Will
ground vibrations be strong enough to cause structural damage?  Questions
such as these should be answered both at the specific noise sensitive  sites
previously mentioned and at the project boundaries.  The boundary  line
considerations are important when there is vacant land adjacent to the
project site that could be developed.  Although it is usually evident, it  is
also good practice to identify which sources are the major contributors  to
the noise impact.  This knowledge is needed in order to specify effective
mitigation measures.
The impact of construction noise, although it is only temporary, can be
substantial.  In the immediate neighborhood of the site earth moving and pile
driving activities can generate substantial annoyance.  Hauling truck  traffic
can extend the impact to areas far beyond the project boundaries.   The reviewer
should ascertain that the EIS has assessed these impacts.  Too often only  a
token effort is made.
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ARE MITIGATION MEASURES ADEQUATELY CONSIDERED?
After all of the noise analysis has been presented it may become evident  that
mitigation efforts are warranted.  The EIS should explicitly identify such
situations, provide a discussion of applicable mitigation measures,  and
their benefits, and provide a clear-cut statement of the degree of commitment
in implementing them.  We see more than a few EIS's that simply dismiss
mitigation with a wave of a hand and with unsupported statements that mitigation
would be either too expensive or ineffective.  It is possible that these
conclusions are accurate, however, the EIS must provide supporting documentation.

The reviewer should view the inclusion of a well  prepared mitigation chapter
into the EIS as an indication of the project sponsor's commitment to minimize
noise problems.  This assumes, of course, that the sponsor has indicated  that
he intends to implement some of the measures.

NOISE SENSITIVE PROJECTS  There are many ways that a developer can lessen the
intrusive noise impact on his project.  The choice of a quiet location to
begin with is, of course, the best way.  If this  is not possible, there are
design and construction practices that can ameliorate the problems.
"Soundproofing" buildings or constructing noise barriers can be effective.
The adoption of land use codes by the local government can insure against
future problems.
We see housing projects, in particular, where only a part of a
project will  experience excessive noise.  It is not uncommon for the EIS  to
ask for an exemption from normal standards based  on the fact that some other
portion of the project has already been completed or that only a few people
would be affected.  The reviewer must use his own judgement as to whether
such arguments are justified or whether they are  simply a smoke screen to
avoid further expense irregardless of the need for mitigation.
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NOISE GENERATING PROJECTS  Most (non-transportation)  noise problems  related  to



a project can be controlled by proper design considerations prior to the



construction phase of the project.  Choosing equipment locations with regard to



noise considerations, providing mufflers for air handling machinery, vibration



isolating heavy equipment, and using the facility itself as a noise  barrier



are examples of mitigation measures that can be designed into a site at a



fraction of the cost that refitting would require.  If the project is by



nature one that the noise would be difficult to control (e.j. a racetrack or



an amusement park), it is possible to minimize noise impact by restricting



operating hours.
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APPENDIX - REFERENCES

1.  Information on Levels of Environmental  Noise Requisite  to  Protect Public
    Health and Welfare with an Adequate Margin of Safety, U.S.  Environmental
    Protection Agency, Washington, D.C.  EPA 550/9-74-004,  1974

2.  Guidelines for Preparing Environmental  Impact Statements on Noiser
    Commitee on Hearing, Bioacoustics, and  Biomenchanics, National Research
    Council, National Academy of Sciences,  Washington,  D.C.  1977

3.  Design Guide for Reducing Transportation Noise in and Around Buildings,
    D. Pallet, et al, Department of Commerce, National  Bureau  of Standards,
    Washington, D.C. 1978  Stock Number 003-003-01687-0

4,  Department of Housing and Urban Development:  Noise Abatement and Control
    Policy, USEPA, EPA 550/9-77-354, 1977
5.  Noise From Industrial Plants. USEPA, NTID300.1 1971
6.  Noise from Construction Equipment and Operations, Building  Equipment,  and
    Home Appliances, USEPA NTID300.1, 1971
7.  Handbook of Noise Control, Cyril Harris, Editor,  McGraw-Hill, 1957
8.  Noise Reduction, Leo Beranek, Editor, McGraw-Hill,  I960
9.  The Audible Landscape:  A Manual for Highway Noise  and  Land Use, U.S.
    Department of Transportation, Federal Highway Administration, Washington, D.C.
    20402  Stock Number 5000-0007
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