ILLINOIS POLLUTION~CONTROL BOARD
October
6,
1983
IN THE MATTER OF CHAPTER
8:
NIOISE
)
POLLUTION,
RULE
206,
SITE SPECIFIC
)
OPERATIONAL LEVELS FOR FORGING SHOPS
R82—31
Amforge Division of Rockwell
)
Dockets
A,
B,
and C
International
)
Modern Drop Forge Company, and
)
Wyman—Gordon Company
FINAL ADOPTI9~_
OPINION OF THE BOARD
(by 3.
D.
Dumelle):
On November
3,
1982,
the Amforge Division of Rockwell
International
(Amforge), Modern Drop Forge Company
(Modern) and
the Wyman-Gordon Company
(Wyman-Gordon)
individually petitioned
for site—specific operational
levels for their forging
shops, as
alternatives to compliance with the noise
limits contained in
Rule 206 of Chapter
8:
Noise Pollution.
All three petitions
were accepted by the Board on November
12,
1982.
By Board Order
Amforge was assigned to Docket A of this proceeding,
Modern to
Docket
B,
and Wyman-Gordon
to Docket
C.
That Order also served
to incorporate the record
in R76—14,
the general rulemaking on
impulsive noise
from
forging shops.
The
Illinois
Environmental
Protection
Agency
(Agency)
filed
its
Recommendations
on
February
9,
1983.
The
requisite
pub’Lic
hearings
were
held
in
Harvey,
Illinois on February 15,
1983.
No
members
of
the
public
attended and no public comments were received on any of the three
Dockets.
First Notice was adopted on May 19,
1983 and was
published at
7 Ill.
Reg.
7243,
On July
22,
1983 the Board ordered
the proposed rules
to Second Notice and the Joint Committee on
Administrative Rules certified no oblection on September
22,
1983.
Each petition was filed pursuant to subparagraph
(d)
of Rule
206:
Impact Forging Operations, which was adopted on July
21,
1982 as a part of the R76—14 rulemaking, and became effective on
September
1,
1982.
As indicated above,
Rule 206 contains the
numerical limits for noise generated by forging
shops.
It also
provides
an alternative.
Specifically, subparagraph
(d) allows an
existing forging
shop to petition the Board for a site—specific
operational plan which in effect will,
limit the shop’s noise
emissions.
The petitioner, must demonstrate that
it is
L.echnically
and
economically impractical
for
its
shop
to meet
the numerical
limits.
Each petitioner
muse.
not only explain
its inability to
comply with the numerical
limits,
but must also propose the means
for reducing impulsive noise
as much as possible and assess the
consequential health and welfare impacts on the sur:rounding
community.
Subparagraph
(d)
also sets out the procedural format
for this type of relief.
The petition must include the nine
points of information delineated in the Rule;
the Agency
is to
54-197
2
submit a Recommendation on the petition;
and
a public hearing
must
be held.
For each Docket,
all three requirements were satisfied.
Following
is a separate discussion
of:
each Docket,
including
a description of the individual facility, its inability to abate
noise through structural
or operational
changes,
its past abate-
ment efforts,
and its proposed plan,
if
any,
to reduce impulsive
noise.
The economic ramifications and
accept;~l’i.i~.tyof
each
proposed plan are also discussed.*
DOCKET A:
AMFORGE DIVISION OF ROCK~ELE~
INTEPJThTlONJ~
The Amforge complex
is
located on 119th Street, between
Loomis and Racine Avenues
in Chicago, covering appprosirnately
four city blocks, or seventeen acres.
Two buildings,
the axle
and hammer shops, house the An~forgeforging operation which
manufactures,
among other items,
parts
for the agricultural, off
highway equipment,
trucking,
railroad, and construction industries.
Amforge has twelve hammers ranging from 3,000
to 12,000 pounds to
manufacture forgings ranging
in size ~rom three to three hundred
pounds.
Very simply a forging hammer consists of two dies,
each
of which is attached
to
a guided ram
and
an
anvil.
The
metal
to
he
shaped,
i.e.
forged,
is
placed
between
the
ram
and
anvil.
The
guided ram with its die is then driven against
the
lower die atop
the anvil.
The impulsive sound is generated by the resulting
impact.
Fifteen furnaces service Amforge’s hammers, each with the
capacity of heating approximately 5,000 pounds of metal per hour.
To bring the steel
to forging temperature,
the furnaces must reach
2,350 to 2,400 degrees Fahrenheit.
(Pet.
3,4, and R.21).
The hammer shop is forty feet high,
ninety feet wide and one
hundred and seventy feet
long.
The axle shop
is likewise
forty
feet high, but fifty feet wide and one hundred feet long.
Both
buildings are similarly structured with fiber—glass doors on the
bottom, windows above
that, and
roofs of corrugated
sheet metal.
The buildings have been designed to create the “stack effect”,
that.
is natural ventilation of the furnaces’ heat.
Inside air, heated
by the furnaces, induces the outside cooler air into the building
through the multiple large door openings, causing air currents
to
rise and exhaust through vents
on the roofs.
The shop’s noise,
impulsive and otherwise,
is also emitted through these vents.
The axle and hammer shops were built about forty years
ago.
At that time the surrounding area had few residential houses.
Now,
the areas south and east of the complex are primarily
industrialized,
including a lunkyard, a railroad switching yard
and other
noise generating industries.
(Exs.
D
& E).
Only to
the north and west are there residential properties, most of them
constructed since
1945.
(Pet.
2,3 and R.19).
These residential
areas qualify for Class A protection.
Petitioner estimates, based
*While ~Eh~seamendments were in First and Second Notice,
pending
final
action,
Chapter
8:
Noise was codified pursuant
to
the Administrative Procedure Act
(Ill.
Rev. Stat.
1981,
ch. 127,
par.
1001 et ~
Chapter
8 is now contained
in
35
Ill. Adm.
Code SubtitTe H:
Noise, and Rule 206
is at Section 901.105 of
thai~.
Subpart.
The remainder of this Opinion uses the codified numbers.
54- 198
3
on the daytime noise
limits of 58.5 Leg,
that its operation’s
noise levels could affect one hundred and fifty-five residences.
If the nightime level of
53.5 Leq
is used,
this number is
increased by four hundred and eighty-eight possibly affected
residences
(Pet.10),
Amforge currently ernployes 145 persons.
It employed as many
as 600 in 1979.
It can operate three shifts,
six days a week;
that
is from 7:00 a.m.
until 3:00 p.m.,
3:00 p.m. until
11:00 p.m.,
and 11:00 p.m. until
7:00 a,m..
It has not, however,
since 1979
operated the third shift,
and
as of January
19,
1983 the facility
was mothballed for at least six months,
The chart below provides
the approximate number of
forgings,
the
total
tonnage
of
forgings,
and number of blows creating impulsive noise
for the years
1979
through 1981
(Pet.5),
At hearing Arnforge added that 10,142 tons
were forged in 1982 and estimated that less than
5,000 tons would
be forged this year.
(R,25).
No.
of
Forgings
No,
of
Tonnage of
All
On
Hammers
Blows
_~~ns
1979
1,016,744
14,234,416
26,422
1980
698,025
9,772,350
15,806
1981
474,940
6,649,160
14,566
Having
monitored
its
noise
levels
in 1980 Amforge represented
that the highest level
recorded at nearby
residences
was
70
Leq.
(Ex.C,
R.27).
In order
to reduce this
level
to
that
required
at
Section 901.105(c).
Arnforge investigated three different means
for abating the impulsive noise,
The
first
would have required
that the ground level openings, the windows,
and the roof vents
be enclosed.
This alternative would have meant that the “stack
effect”
of the buildings would he forfeited and replaced with
mechanical ventilation.
Mechanized ventilation would entail
exhaust fans
and silencers placed
on the rooftops.
A single
fan
and silencer would weigh approximately 2,410 pounds.
(R.37),
Amforge estimated that eight fans with silencers would have to
be installed atop each building.
The cost per ventilator was
estimated at $4,325 apiece, or $69,200 total, while the cost per
silencer was estimated at $2,650 apiece,
or $42,400 total
(Ex,I).
Regardless of cost,
Amforge did not believe that the rooftops of
either building could
support the weight.
(R,37).
In addition to mechanical ventilation,
Arnforge considered
building barriers outside of the building
to obstruct the noise
emitted through the ground
level
doors.
The barriers were
proposed to be one hundred to two hundred feet to the north,
west,
and east of the shops.
Not only do personnel and air move through
these doors some eighteen feet wide,
but also materials to and
from the operation, e.g. fuel oil,
steel used
in the operation,
and cooling forgings.
Should the barriers be constructed, Amforge
testified that they would obstruct these essential movements
thereby impairing the shop’s operations.
(R31—34).
Amforge also
54-199
4
cited testimony given by forge shop workers during the R76—14
rulemaking.
That testimony indicated that should the doors be
closed and barriers be constructed, the shop employees would
suffer from the furnaces’ heat and experience
a discomforting
effect from the loss
of natural
light, which
in turn would
greatly affect productivity (R.76—14, February 23,
1981,
pp.
270—274 and 429—431).
(R.34—35).
Initially the barriers were proposed by Amforge’s noise
expert.
Their distance and height from the shop were based on
the classical diffraction theory for optics.
However,
sound
measurements have since indicated that the wind changes the
diffraction patterns so significantly that the barriers would not
be effective downwind
(R.59).
This same phenomena means that
should the bottom half of the shop be enclosed and the sound
directed upwards through the roof and towards the
sky, the wind
could direct the noise waves towards the ground.
Thus
the
shop
would have to be totally enclosed.
The last alternative considered by Amforge was to pad the
hammers.
Absorbent pads made out of Fabrika, could be placed on
the hammers’ mechanical parts when each individual hammer
is
overhauled.
(R.39).
AiTiforge’s noise expert believed that proper
placement of the pads might reduce the acceleration forces,
thereby reducing some of the forge frame’s vibrations,
Reducing
the ringing on all
the structures may seem to somewhat lower the
total sound omitted, however, the pads would not effectively
reduce the highest sound level
impacts, that
is the
inpuisive
sound.
(R. 57),
This same noise expert took the noise readings
in the area
of the Amforge
shop.
As stated earlier,
these measurements
indicated the highest Leg to be 70,
The isopleths developed from
these measurements demonstrated that residences downwind suffered
from higher noise
levels.
The difference between downwind and
upwind was as much as approximately two decibels per 100 feet
from the
shop.
Therefore,
at 1000 feet the difference between
a
downwind or upwind location would be twenty decibels.
Given
this, the number of affected residences mentioned above must be
qualified.
During the daytime
it is likely that only a part of
the one hundred and fifty-five residences,
those directly down-
wind, would experience
levels greater than the allowable 58,5 Leq
whereas the levels upwind may be below that
level.
The same
holds true for the additional four hundred and eighty—eight
residences originally considered
to be exposed
to levels greater
than the nightime level of 53.5 Leq.
The Agency’s Recommendation assessed the ability of the
Amforge facility to abate
sound, and the health and weltare
effects on the nearby community should
it not,
Principally, the
Agency considered acoustical strengthening.
This would require
reducing the number of ventilation openings, installing duct
silencers at ventilation openings and gravity ventilators
at the
54-200
5
roof openings.
The
Agency agreed with Amforge that these three
efforts would hamper the “stack effect”
this ~ihopdepends on.
As for the impact on the nearby community, the Agency found that
only thirteen homes would receive levels as high as 70 Leq, while
an
additional
thirty—six
would
receive
levels
as high as
65
Leq;
101 a level
as high as 60 Leg,
and 119 homes impacted at levels
as
55 Leg.
The Agency’s Recommendation also notes that since
1972,~no citizen complaints have been received about the Amforge
facility.
In assessing the health and welfare effects,
the
Agency’s Recommendation cited the
United
States
Environmental
Protection Agency’s document “Information on Levels of Environ-
mental Noise Requisite to Protect Public Health and Welfare with
an Adequate Margin of Safety”.
(Recommendation,
Ex,8)
This
study acknowledged that it
is difficult to access the effects on
health caused by impulse noise because
it is necessary to take
into account other factors such as the background noise, and the
number and duration
of
the
daily exposure.
The study found that
impulse noise exceeding background noise by 10
dF3 is potentially
sleep disturbing
and
startling.
However,
the study concluded
that no threshold level could be
identified, or that there was
any clear evidence of permanent effect on public health and
welfare.
As its
alternative
compliance
program,
Arnforge proposed
three operational changes.
It has agreed to reduce
the number of
operating hammers from twelve to ten;
limit operations
to two
shifts which will mean the forging
shop
will
operate from 7:00
a.m.
until
11:00 p.m.,
and occasionally from 6:00 a.m.
until
12:00
midnight;
lastly,
as
the hammers are overhauled (approxi-
mately every three years),
the sound absorption pads described
above will be installed,
Aimforge estimates that removing two
hammers
from
operation
and
curtailing
the hours of operation to
sixteen per twenty—four period its potential forging operation is
reduced by 39.1,
It could not,
however, express this cutback
in
a dollar amount,
It should be noted that the Amforge petition
lists sound
abatement measures taken at the facility since
1972.
For
instance,
mufflers,
silencers,
and
snubbers were installed on
hammers, presses,
and on air compressors;
eleven hammers were
removed from service; part of the hammer shop was rebuilt with
noise insulating materials; and the ground level doors were
repaired or replaced.
Some of these efforts
directly
reduced
the
amount of impulsive noise,
while other abated other manufacturing
noise.
The costs of these improvements ranged from $1,803,000
for rebuilding part of the hammer shop,
to $3,800
for the work
done on the ground
level doors,
The economic impacts to the individual
shops, to~theState
and otherwise were initially considered in the R76—14 proceeding.
The Economic Impact Study submitted by
the
then
Institute
of
Natural Resources did investigate
the
cost
of abatement for ten
individual
forging shops.
Ainforge was one
so
studied.
The
54-201
6
combined capital and operating costs for reducing noise emissions
by successive
5 dB increments in 1978 dollars was estimated to
range
from $424,000 for a 5 dB(A) reduction to $714,000 for a 15
dB(A)
reduction.
(INR Document No.
78/03, pp.
39-40)
Although
Nnforge along with nine other shops, was individually examined,
these dollar amounts were standardized for purposes of the
report.
DOCKET
B:
MODERN DROP FORGE COMPANY
Modern’s facility occupies approximately four blocks
immediately northwest of the intersection of 139th Street and
Western Avenue in Blue Island,
Illinois.
The first
forge shop
was constructed
in 1918,
and
a second built in the
1940’s.
Since
then numerous support buildings have been added.
Modern operates
twenty—one hammers and numerous furnaces,
The air drop, air
driven hammers range
in size from 2,000 pounds to 8,000 pounds,
while each furnace can heat up to 1.3 tons of steel per hour to
a
temperature of nearly 2,000 degrees Fahrenheit.
The forgings
produced range in size up to forty pounds and include among other
items connecting rods for engines, pinions, and gears
for the
railroad industry, and shifting levers
for transmissions.
Modern currently employs 263 persons
(R.
16).
Historically,
Modern operated two shifts from 6:00 a.m.
until
midnight, with
occasional Saturday shifts from 6:30 a,m, until
7:30 p.m.
Currently,
the forging operation is from 6:30 a.m.
to 10:15 p.m.
five days a week.
The chart below provides the approximate
number of forgings manufactured, the total tonnage of forgings,
and the number of blows creating impulsive noise for the years
1979 through 1981
(Pet.
5).
At hearing, Modern estimated that
7,200 tons were forged in 1982 and approximately 8,000 tons would
be forged in 1983
(R.
17),
No. of Forgings
No. of
Tonnage of All
On Hammers
Blows
Forgings
1979
24,800,000
109,282,000
15,900
1980
18,800,000
92,475,000
13,350
1981
12,746,000
67,477,000
9,780
Modern is primarily surrounded by other industrial
facilities.
Directly north is
a warehouse and trucking
operation, east
a roofing company,
and directly south in one
industrial park is another roofing company, a potato processing
plant, incinerator manufacturer, and pattern works.
Numerous
scrap yards and railroad switching yards
are also
in the
vicinty.
A girls school is directly east of Modern, while trailer parks
are northeast,
east and southeast of Modern,
Like Modern,
however,
these residential areas are surrounded by industrial
54-202
7
complexes and switching yards (Ex.
A).
Nevertheless, these
residential areas qualify for Class A protection under Subtitle H.
wore specifically, impulsive sounds impacting them must not be
more than 58.5 Leg during daytime hours, and 53.5 Leg during
nighttime hours pursuant to Section 901.105 Cc).
Bound measurements were taken by
Modern
using
both
the Leg
measure and 63(A)
(fast meter response).
Data taken on dB(k) was
converted to Leg by deducting 5 U.
Excluding
two
residences
owned by Modern, the highest emission at the closest Class A Land
measured 67
Leg
(Pet.
9).
Using concentric circles, Modern
illustrated the different noise parameters effecting the various
residential locations.
The diagram indicates that the
girls’
school,
the northern trailer park,
and part of one to the
southeast of
Modern
fall within the 65 Leg or greater range.
The
two
smaller trailer parks to the east
and
the remainder of
the southeastern park are within the 55 Leg. to 65 Leg
(Ex.
A).
Petitioner estimated that 1,639 residences are potentially
exposed to sound levels greater than 53.5 Leg
(Pet.
9).
Modern’s two forging shops are of similar design.
The lower
level is composed of brick with ldrge roll—open doors.
Above that
are wire glass panels on one building, and corregated fiber glass
and steel panels on the other.
One
roof is
gypsum
board and
asphalt with a corrugated transite peak, while the other is a cor-
rugated transite roof.
Atop
both
buildings are large open roof
ventilators while along with the buildings’ design provide for
natural ventilation of the furnaces’ heat, commonly referred to
as ‘stack effect’.
The impulsive sound from the forging hammers
also exits through the roof ventilators; thus, the relationships
between adeguate ventilation and sound emitted.
Modern considered two abatement strategies.
The first
entailed totally enclosing the shops and installing mechanical
ventilators.
Structural analysis of both buildings indicated
that the present trusses and related structures would have to be
extensively modified to support the deadweight associated with
additional exhaust units.
Seven additional units weighing 1,300
pounds apiece would be needed for the older, smaller shops which
currently has six trusses.
Ten
units weighting approximately
7,740 pounds apiece,
in addition to the present eight, would be
needed at the newer and larger of the two buildings
(Ex. F).
Modern
claims that for the same structural reasons, sound
absorptive material cannot be installed.
A second means for abating sound would be to construct
barriers between the shops and receiving Class A areas.
Since
1976, Modern has built five structures between itself and the
southern and eastern perimeters, and is currently erecting a
sixth.
In locating these buildings, Modern had inteqded to
obstruct the impulsive noise caused by its operations.
In
building these new structures, Modern used sound absorptive brick,
at an increased cost of approximately three and a half times that
of normal building material.
One
structure was also constructed
to a height recommended
to
obstruct sound movement
(R. 20—21).
54-203
8
Lastly,
Modern enclosed the upper side vents
on its larger
building
(R.
22).
This was intended to direct noise skyward, and
also to improve the “stack—effect’~. While it did improve the
natural ventilation,
the workers objected
(R.
38).
Modern also considered constructing barriers.
To be
effective,
it was thought these barriers would have to be close
to the forging shops.
They would thus interfere with the
facility’s craneway and forklift routes
(R.
28,
29,
Ex.
D,
E).
Modern also
introduced
testimony
from the R76-14 proceeding,
as
to the effect such barriers would have on its employees.
Since
the barriers would have to be
constructed close
to the shops,
they would in effect cut off light and air
(R.~ 30),
Two employees
of forging shops, one from Modern, testified that would create
intolerable working conditions
(R.
76—14, February 23,
1981,
R.
270—274;
R. 429—431).
In taking
the sound measurements, the buildings and
other barriers were found ineffective at distances greater than
200 feet beyond the barrier because weather conditions affected
the noise pattern.
Locations downwind registered higher noise
levels than those upwind from the source,
Even without wind,
weather conditions interfered with the barriers’ intended
effectiveness.
On sunny days,
the heated ground causes the noise
to be diffracted upwards very rapidly
(R.
43—96),
Thus, the
barriers,
regardless of height or material specifications,
failed
to stop impulsive noise
from reaching
Class
A
Land.
Evidence
of
this diffraction pattern,
incidentally,
is the reason Modern used
concentric circles rather than irregular isopleths to illustrate
noise patterns.
Modern was only aware of one complaint about the impulsive
noise generated from its neighbors; which was made in 1977 in
response to 2:00 a,m.
operations.
Modern has since discontinued
the then experimental early morning third shift
(R.
24).
During
the R76~-14proceeding Modern also conducted a survey of the
affected residences and only one complaint was registered
(R.
76—14, February 24,
1981,
R.
433—435,
441—444).
The
Agency~s
Recommendation cited
no
known
complaints.
Furthermore,
the Agency
estimated that only
5
to 10
of the 1,639 homes considered by
Modern would receive levels as high as 67 Leg.
Pursuant to Section 901.105(d) (2) (G) petitioners
for a
site—specific rule are to include proposed operational
levels and
physical abatement measures,
if
any, which are intended to reduce
the facility’s impulsive noise.
Modern does not propose to change
its operations or,
in the
future,
install
or
construct
sound
abatement mechanisms.
However,
since 1976,
Modern has undertaken
six
construction projects which directly and indirectly were
intended to reduce impulsive
noise,
Modern
not
only
designed
and
located building construction to act as barriers, but also used
sound absorptive material on those walls facing the forging shops.
Modern also closed the upper vents on the larger shop and the
southern end of the smaller shop
(R.
23).
Modern is also in the
process of installing sound attenuators on its dust collectors.
54-204
9
This last measure will not reduce impulsive noise, but should
effectively reduce other noise emitted to nearby residences,
Cumulatively, Modern estimates that the sound abatement measures
associated with these construction projects have cost approxi-
mately $24,000
(Pet.
7—8).
The R76—14 Economic Impact Study
estimated that
it would
cost
Modern $424,000 to reduce impulsive
noise by
5 dB(A) and up to $1,231,000 to reduce
it by 20~dB(A)
(INR Document No,
78/03,
p.
39-40).
A
20 dB(A)
reduction was
then considered necessary for Modern to comply with the numerical
noise limitations.
Modern represents that future efforts to reduce impulsive
noise to compliance
levels would require total enclosure of its
two shops,
thereby eliminating the buildings’
‘~stackeffect”.
Replacing natural ventilation with mechanized ventilation is not
feasible given the buildings’
current structure.
Enclosing the
shops
is also unacceptable from
a productivity viewpoint.
Large
materials must constantly be moved
in and out
of the buildings,
and the shops’
employees would not accept conditions
which would
shut out natural
light
and air.
Historically, Modern has not operated an early morning third
shift.
It cannot,
therefore,
propose
to eliminate
it.
Modern
does request that
it be allowed to operate between 6:00 a.m.
until midnight, although
it ordinarily operates
no later than
10:15 p.m.
Therefore,
those residences located only
within
the
nighttime noise
limit parameter,
will be adversely affected for
no more than two hours per week day.
Impulsive sound
is
considered disruptive to sleep according
to the
tJSEPA document
“Information on Levels of Environmental Noise Reguisite to
Protect Public Health and Welfare With an Adequate Margin of
Safety”.
(Agency Recommendation,
Ex.8)
That same document,
however, did not establish
a threshold level
for health or
welfare impairment.
The Board notes that no complaints have been
filed in the recent past concerning Modern’s forging operations.
Perhaps the industrial character of the area renders Modern’s
impulsive noise
less obtrusive.
DOCKET
C:
WYMAN-GORDON COMPANY
Wyman—Gordon’s facility
is located
on approximately
66 acres
immediately north and northwest of the intersection of 147th
Street
(State Highway
83)
and Wood Street
in Harvey,
Illinois.
Ten forging units, each consisting
of two hammers,
are housed
in
four separate buildings,
identified
as Nos.
6,
7,
67 and
75.
The
steam driven hammers range
in size from 10,000 pounds to 30,000
pounds, and produce forgings ranging
in size from twenty—five to
over 1,000 pounds.
The forgings produced include among other
items crankshafts
for agricultural and off—road equipment,
parts
for the aircraft,
the aerospace and the under sea exploration
industries.
The table below provides the approximate number of
forgings manufactured on these hammers, the number of blows
54-205
10
creating impulsive noise, the total
number of
forgings and the
total tonnage of
forgings for the years 1979 through 1982.
(Pet.
6,
R.17).
At hearing, Wyman—Gordon projected that 11,000 tons
would be forged in 1983.
No.
of
Forgirigs
No.
of
Total No.
Tonnage of
All
On Hammers
Blows
Of Forgings
Forgings
1979
319,136
6,382,720
475,260
55,646
1980
220,684
4,413,680
344,863
42,732
1981
163,485
3,169,700
285,657
38,629
1982
1,175,980
58,799
7,590
Wyman—Gordon began its operations on 1919,
Although four
buildings previously contained hammer units,
the single unit
in
Building
67 has been shut down.
Therefore,
three buildings
constructed before 1940 now house the remaining units and thirty
to forty furnaces,
Individually,
these furnaces are capable
of
heating up to 16,000 pounds
of steel per hour to a minimum
of
2,200 degrees Fahrenheit.
To exhaust the tremendous heat
generated,
all
three buildings were designed to create a “stack
effect” for natural ventilation.
The end walls are partially
made of brick with some upper
level windows and corrugated
asbestos siding.
The principal walls have numerous grade
level
doors
and side wall windows.
Roofs
are of federal cement tile
with
a monitor containing
operable sash windows.
The
ground
level doors,
side windows,
and roof windows are all necessary
openings for ventilation.
It
is
through these same openings that
impulsive sound
is emitted.
Currently, Wyman-Gordon employs
380
persons,
and
at the time of petitioning
it employed 600 persons.
(R.15,
Pet.4).
At this time the forging hammers are operated
between 7:00 a.m.
and 3:00 p.m.
Historically, the hammers were
operated during two shifts,
from 7:00 a.m. until 11:00 p.m.
six
days per week.
Occasionally,
isolated units begin at 6:00 a.m.
or end
at midnight.
A third shift has not traditionally been
utilized.
Wyman—Gordon’s facility is surrounded by residential
property which qualifies for Class
A protection under Subtitle H.
The plant and Wood Street
is bisected by two railroads.
An
average
of eighteen trains operate daily,
which
along with
a
manufacturing complex to the west contribute
noise to the area.
Wyman—Gordon estimated that 1,263 residences
are potentially
exposed to levels
in excess
of
58.5 Leg. and
794 additional
residences exposed
to levels exceeding
53.5.
These measurements
are respectively the daytime and nighttime maximum exposure
levels allowed under Section 901.105(c).
54-206
11
The highest noise
level, measured and therefore anticipated
at the closest Class A Land is
74 Leg.
The 74 Leq. measurement
was taken
in the vicinity of only three to four homes, which were
just north of Building 75.
Wyman-Gordon qualified this as the
worst case condition, only occurring on days when these
residences were downwind.
The total number of residences was
likewise qualified;
only those in downwind quadrants receive
levels greater than allowed by Section 901.105.
Therefore,
the
entire number of potentially affected residences would not be
subject to excess levels at any one time.
(Pet.
9,
10,
R.
19).
Wyman—Gordon has over the years already taken
steps to
reduce the noise,
impulsive and other,
emitted beyond
its peri-
meter.
Between 1952 and 1978 it expended $462,937 to acquire
approximately twenty—one acres contiguous to its property.
This
land is vacant and acts as
a buffer between the plant and nearby
residences.
Secondly,
in 1979 Wyman—Gordon installed two roof
ventilators at Building 75,
at
a cost of $84,000,
not including
internal engineering and labor costs.
Each vent is nine feet
wide by ninety feet long and directs heat and impulsive sound
upward.
Each ventilator contains two vertical panels,
each lined
with glass
fiber sound absorptive material.
Installation of the
ventilators allowed the openings on Building 75’s north
side to
be
closed.
Northern residences, when downwind, benefit by a
sound reduction of approximately
4 decibels.
(Pet.8).
In 1982,
Wyman—Gordon shut down two hammer units,
each consisting of two
hammers.
Both units were contained in buildings on the
facility’s southern boundary.
In eliminating one of two units
in
Building
7,
and the only unit
in Building
67,
the potential for
excess
levels impacted residences
to the south was reduced.
(R.18,
Pet.8).
Lastly,
between 1974 and 1979 Wyman-Gordon
installed mufflers
to reduce non—impulsive noise
from all
its
steam vents at
a cost of $32,000.
Wyman—Gordon considered totally enclosing the three
remaining forging shops,
Buildings
6,
7,
and 75.
However the
cost,
size and weight of the necessary exhaust fans,
silencers
and duct systems were prohibitive economically, but more
important,
structurally.
(R.26).
For example,
two silencers
would be required at Building
75 costing
a total of $12,000,
along with four ventilation fans at $84,000.
Duct work
for
Building 75 was estimated
at $181,700.
(Ex.H).
Regardless
of
the high cost, Wyman-Gordon testified that the three buildings
would be unable
to support the weight associated with mechanized
ventilation without substantial reinforcement
of the present
structures.
(R.26).
Wyman—Gordon also considered constructing four barriers.
The one proposed at the facility’s north end would, however,
obstruct
a craneway and the roadway providing access far street
trucks to and from its principal steel
yard.
A new roadway was
estimated to cost
a total
of $114,365.
(Ex.F,
R.22).
54-207
12
Construction of a second barrier at the southern end of the
facility, would interfere with the movement of steel
in and out
of one building.
To maintain production levels,
an additional
truck and driver would be needed at an estimated annual cost of
$125,398.
(Ex,6,
R.23).
Yet two more barriers at the southern
end would obstruct
a craneway and the shops’ natural ventilation
and light.
(Ex.E,
R.24).
Wyman—Gordon proposed both physical
changes and operating
changes in order to reduce impulsive sound received at nearby
Class
A Land.
Primarily, Wyman—Gordon will concentrate
its
forging operation to Building
75,
which is approximately
one-fifth of
a mile north
of its southern forging shops.
Buildings
6 and
7 will therefore not be used for more than 20
of
the total operation. Already Petitioner has eliminated two units
operating in Buildings
7 and 67, which are located at the
southern edge of its property.
It is further willing by
January
1,
1984,
to remove another unit from operation.
That
will mean
a 40
reduction of the ten units previously operated.
As noted above,
it was Building
75 which had its northern
facade closed to reduce noise emitted
to northern residences.
In
an effort to further reduce noise
to the north, Wyman-Gordon
proposes to consolidate two existing steel stockpiles into one
which is to be located north of Building
75.
The consolidated
yard is to act as a noise barrier during ideal atmospheric
conditions.
(R.29,Pet 13).
Like other barriers,
its intended
purpose
is defeated whenever wind or heat diffracts noise over
it.
(P.41,
44).
At best,
the stockpile should reduce noise
levels by
1 dR or more.
(Pet.13).
Wyman—Gordon is aware of the ineffectiveness
of barriers
because four other buildings are already located just north of
Building 75.
These building shield all but one of the units
in
Building 75.
In theory,
these buildings should produce an
approximate
20 dB reduction.
However, measurements indicate that
noise is reduced by just
3 dB (R.45).
Nevertheless, Petitioner
proposes to consolidate
its steel yard
in a location to shield
the one unit not already blocked to the north.
Lastly, Wyman-Gordon proposes to limit the amount produced
during its hours
of operation.
Forging operations will continue
as before, primarily between 7:00 a.m. and 11:00 p.m. six days
a
week,
and occasionally begining
at 6:00 a,m. and ending at
midnight, with occasional Sunday shifts.
However,
it proposed to
restrict operations during the latter to 2
of its annual
total
hammer productions.
(P.27,30,54).
In addition to these efforts,
it
is noted that Wyman—Gordon has already invested money and
action towards consolidating production at Building
75.
Building
75 was itself renovated and partially enclosed, and Building 67
eliminated
as a forging shop.
54-208
13
The past efforts and future consolidation Wyman-Gordon
estimates will cost nearly $2,000,000.
(R.30).
The Economic
Impact Study estimated that for the Wyman-Gordon facility to
reduce impulsive noise emissions by 25 dB(A), the amount
necessary to be
in compliance with numerical limits, was
$1,715,000.
That was based on 1978 dollars, which also had been
standardized in a study of ten forging shops.
(fliP Document No.
78/03, pp.
3940).
The plan now proposed by Wyman-Gordon will
cost approximately the same amount, but is anticipated to reduce
the noise
level by
1 to
3 dB(A).
The difference in cost is due
not only to inflation,
but because
it has now become apparent
that shops
like Wyman—Gordon cannot be totally enclosed and that
sound barriers do not perform in actuality as formerly believed
in theory.
Inability to enclose and inefficiency of barriers
accounts for the difference
in noise reductions anticipated.
CONCLUSION
In adopting the alternative of site—specific operational
levels in P76—14, the Board concluded that given these figures
and other information made it apparent that a number of small
Illinois forging shops could not achieve the necessary noise
abatement for reasons technical and economic.
Therefore,
instead
of
a standard noise
level the shop’s operational plan becomes the
rule within Subtitle H and the individual shop must comply with
it.
In no instance may such
a plan allow an increase
in existing
decibel
levels, rneasuredin Leq.
In the matter of Docket
A, the Board accepts
Aniforge’s
assertion that the two buildings could not structurally bear the
weight mechanized ventilation would entail.
Therefore, the only
means
for totally enclosing the hammer and axle shops would be
to
rebuild the existing buildings.
Secondly, the formerly
acceptable abatement measure of barrier construction has been
discredited as
an effective method to reduce impulsive sound.
It
then appears that impulse forging noise can only be reduced
in
this case through operational changes.
Aniforge has agreed to
eliminate its late night work shift as well
as two of the twelve
hammers.
In addition,
Amforge has agreed to reduce the noise
generated by the remaining hammers by installing absorption
material.
The operational changes are directed at reducing
impulsive sound, while installation of sound absorptive pads on
the hammers
is intended to reduce the shop’s other noise level.
This plan, along with the other noise abatement measures taken
over the preceeding ten years should provide relief to the nearby
Class A lands.
The plan as set out in the accompanying Order is
incorporated into Subtitle H at Section 901.105(f) (1), and 2\mforge
is, therefore, required to comply with it.
As for Docket B,
the Board must conclude that short of
totally enclosing the shops,
Modern has already installed noise
barriers to the furthest extent possible.
Although these have
54-209
14
proven inefficient on windy or sunny days, they will hopefully
provide the community some protection from impulsive noise,
if
only during days of no wind or sunshine, and during nighttime
hours.
At this time,
Modern will not be required to make any
specific physical changes to reduce impulsive noise, but is
encouraged to continue replacing or locating new structures
conducive to reducing noise
levels.
Lastly,
Modern will be
restricted to operating its forging hammers between the hours of
6:00 a.m. through midnight on weekdays, and 6:30 a.m. through
7:30 p.m.
on Saturday, with no Sunday operations, pursuant to the
plan adopted at Section 901.105(f) (2).
In the matter of Docket
C, Wyman—Gordon proposes to move its
operations to Building 75 at the northern perimeter of its
facility.
As mentioned above, the 74 Leq.
reading was measured
at three to four residences just north of Wyman—Gordon’s
facility.
Enclosure of the Building 75’s north side, the
existence of the four buildings just north of it, and the
doubling the size of the steel stock pile should minimize these
incidents.
Impact on southern residences should be reduced by
Wyman—Gordon limiting operations in Buildings
6 and
7 to no more
than 20
of its annual production.
Finally,
since Wyman-Gordon
should routinely operate no more than one hour during nighttime
hours as defined by Subtitle
H, the probability of sleep being
disrupted should be reduced.
To insure these noise reductions
andlimitations, the plan proposed by Wyman-Gordon and found
acceptable to the Board is adopted at Section 901.105(f) (3)
This Opinion supports the Board Order in this matter,
adopted this same day.
I,
Christan
L. Moffett, Clerk of the Illinois Pollution
Control Board,
hereby1 c~ertifythat the above .Opinion and Order
was adopted on the
(c
L
day of
t~~--ft
l983byavoteof
4~c
.
Christan
L. Mof~J/~,Clerk
Illinois Pollution Control Board
54-210
