HomeMy WebLinkAbout2.0 BOCC Staff Report 11.04.1996BOCC 11/4/96.
PROJECT INFORMATION AND STAFF COMMENTS
REOUEST: Special Use Permit for a natural gas
compressor and related equipment.
APPLICANT: Snyder Oil Corporation (SOCO)/Southeast
Piceance Joint Venture
LOCATION: A tract of land located in Section 13, T6S,
R94W of the 6th P.M.; approximately two (2)
miles west of Rifle.
SITE DATA: 3.859 Acres
WATER: Will not be used
SEWER: Will not be used
ACCESS: Access to County Road 264; easement
EXISTING ZONING: R/L (Gentle slopes/lower valley floors)
ADJACENT ZONING: R/L
I. RELATIONSHIP TO THE COMPREHENSIVE PLAN
The subject property is located in District D - Rural Areas/Moderate Environmental
Constraints, as designated by the Garfield County Comprehensive Plan's Management
Districts Map (1981; 1984).
Il. DESCRIPTION OF THE PROPOSAL
A. Site Descrip_on: The subject tract is 3.859 acres in size, located approximately two
(2) miles west of Rifle, near the end of County Road 264, among other industrial
users. Questar, Public Service of Colorado, Williams Field Services and others have
similar operations near the SOCO natural gas compressor facility. There are two
washes that run across the property, one on the eastern boundary, the other on the
western boundary, and sage brush is found in and along the wash. There is currently
an existing, approved compressor, as well as a liquids gatheling system and some
associated drip tanks. A vicinity map is shown on page b
B. Project Description- SOCO proposes to install an additional natural gas compressor
unit, as well as a central dehydration unit, designed to streamline operations and
reduce overall air emissions from gas dehydration. The existing compressor unit is
a Waukesha (fueled by natural gas) with an Ariel JGK-4 compressor. The proposed
unit would consist of a Caterpillar 3516 engine, with an Ariel ME -4 compressor.
Except for scheduled maintenance, the facility would operate 24 hours/day, 365
days/year. See the attached Property Survey foldout map.
LU. MAJOR ISSUES AND CONCERNS
A. Easements: The applicant has been granted a surface facilities easement by the owner
of the tract, as well as an access easeinent across intervening land to County Road
264. See easements, pages 7- /I . Additionally, the owner of the tract has
submitted a Letter of Authorization, which approves of the land use proposed by the
applicant. See Letter, page it. .
B. Zonino: The site is within the R/L (Resource Lands - Gentle Slope/Lower Valley
Floor) zone district, which does allow the requested land use, upon the issuance of
a Special Use Permit.
C. Access: Access to the subject parcel is from an easement that intersects with CR 264.
Previously, an internal looped roadway was constructed to provide access to the
perimeter of the parcel. Staff has visited the site and contemplates no specific
problems associated with the access.
Water and Sewer: No water or sewer will be used for this proposed project.
However, given the existing liquids storage and drip tanks and proposed facilities,
there is a potential for accidental spill or release of hazardous materials. The applicant
has adopted a mitigation plan in the event an accident occurs, which staff recommends
be forwarded to the Garfield County Office of Emergency Management.
E. State and Local Health Standards/Permits: An application for a modification to the
Air Pollution Permit, for the existing facility, has been submitted to the Colorado
Department of Health. It appears the modification would allow the addition of the
proposed unit. See Permit application, pages / /9 . To date, the permit has
not been issued by the State, and staff recommends the permit be issued prior to
issuance of the Special Use Permit.
F. Drainage. The site does not exist in a designated flood zone; however, two (2)
washes do exist on the property, more or less forming the eastern and western
boundaries, and construction on the site should be done in a way to prevent further
erosion of the banks or slopes, consistent with the recommendations made in the
Lincoln DeVore soil study.
G. Fire Protection. The applicant addressees a number of fire control and suppression
techniques which should be sufficient to control or contain a fire at the site. There are
some existing drip tanks on the site and the applicant would be required to comply
with the National Fire Code in the storage of these items. See attached Fire Control
Measures, page % 5 . In the event of a fire or emergency, adequate access to the
site does exist. Staff recommends the applicant file an updated emergency plan with
the Rifle Fire Department and the Garfield County Department of Emergency
Management.
H. Noise: Noise assessments have been conducted for the existing compressor unit and
estimates for the new unit have been calculated to determine the amount of noise that
would result from the two (2) units operating simultaneously. The existing
compressor generates the following amounts of noise:
Distance: 80 feet
4300 feet
5000 feet
Sound Power Level:
71 dB(A)
36 dB(A)
35 dB(A).
When the two (2) units are operated simultaneously, the noise levels have been
calculated to increase by 4 dB(A), as measured at the same distances noted below:
Distance: 80 feet
4300 feet
5000 feet
Sound Power Level:
75 dB(A)
40 dB(A)
39 dB(A).
According to information submitted with this data, normal background noise created
by I-70 in the Rifle area is in the 40 to 50 dB(A) range. See attached documentation
on pages /L • 17. For comparison sake, normal, human conversation at three feet is
in the 60 to 65 dB(A) range. The report concludes that, based on these calculations,
no noise mitigation will be required for this expansion.
Traffic: The applicant expects traffic in the immediate area to increase during the
construction of the facility, but would return to levels consistent with the traffic levels
prior to construction. Daily trips to inspect the site will occur, but should not cause
a significant impact.
J. Wildlife Considerations. Impacts caused to wildlife from the construction and
operation of this site should be minimal or non-existent as the site is already
industrial in nature and probably not a part of migration patterns or habitat.
K. Vibration. The operation of the facility would likely cause vibration on and near
the site. According to regulations, the applicant shall be required to construct a
foundation that will make vibrations imperceptible, except by instruments, at any point
outside of the property boundary line where the unit will be located.
L. Soils: The Soil Conservation Service identifies the subject tract as being within the
Arvada loam class, having severe shrink -swell potential. Lincoln-DeVore, at the
request of the applicant, performed a soil study to determine specific soil
characteristics which will be encountered on-site, in an effort to determine the type
of foundation that would need to be built to support this compressor facility. Staff
has reviewed the report and recommends the foundation be built consistent with the
findings of the study. Specifically, control of the shrink/swell potential of the soil,
mitigation of drainage and erosion concerns by the installation of appropriate
structures and damping of vibration.
IV. SUGGESTED FINDINGS
That proper posting and public notice was provided as required for the meeting before
the Board of County Commissioners.
2. That the hearing before the Board of County Commissioners was extensive and
complete, that all pertinent facts, matters and issues were submitted and that all
interested parties were heard at that meeting.
That the application is in compliance with the Garfield County Zoning Resolution of
1978, as amended.
4. That for the above stated and other reasons, the proposed exemption is in the best
interest of the health. safety, morals, convenience, order, prosperity and welfare of
the citizens of Garfield County.
RECOMMENDATION
Staff recommends APPROVAL of the application, subject to the following conditions:
1. That all representations of the applicant, either within the application or stated at the
meeting before the Board of County Commissioners, shall be considered conditions
of approval.
2. Prior to the operation of the additional facilities, all air pollution emission permits shall
be issued by the Colorado Department of Health and operation of the facilities shall
be consistent with the conditions of approval of such permit(s). Upon receipt of the
permit(s), copies shall be submitted to the Planning Department for review.
3. The amount of noise to be generated by the operation of this facility be consistent
with the predicted amounts as contained herein. The predicted amounts will be used
as the maximum allowable level and if sound power levels exceed these limits,
immediate mitigation must take place at the sole expense of the operator of the
facility.
4. The construction of the foundation for the engine/compressor unit and all other
facilities shall be done in a manner to prevent perceptible vibration from occurring
outside of the property boundary as it exists on the Property Survey Map. Any
foundations shall be constructed with respect to the shrink -swell and erosive potential
of the soil, as identified by the Lincoln DeVore soil study.
5. Construction at the site shall be accomplished in a manner to control further erosion
of the parcel.
6. Reclamation and revegetation of the site shall be required when the operator ceases
use of the facility, in a manner that returns the site to its original, preconstruction
state.
7. The applicant file an updated emergency plan with the Rifle Fire Department and the
Garfield County Department of Emergency Management, prior to the issuance of the
Special Use Permit.
3. Any out-of-state vehicles used in the construction, operation or maintenance of the
facility shall be registered or apportioned in the State of Colorado.
9. The Special Use Permit shall be issued upon demonstration of satisfactory compliance
of all listed conditions of approval.
10. The applicant/operator of the facility shall control noxious weeds on the site.
EASEMENT GRANT
FOR SURFACE FACILITIES
FOR AND IN CONSIDERATION, of the sum of Ten Dollars ($10.00) and other good and
valuable consideration, the receipt of which is hereby acknowledged, W. F. Clough, 300 East 5th,
Rifle, Colorado 81650, hereinafter called "Grantor", hereby grants unto Southeast Piceance
Pipeline Joint Venture, a Colorado Joint Venture, 1625 Broadway, Suite 2200, Denver, Colorado
80202, hereinafter called "Grantee", its successors and assigns, an easement for construction,
installation, maintenance, inspection, operation, repair, removal and replacement of a natural gas
compressor, a vapor recovery compressor, glycol dehydration units, an air compressor with building
and tank and other equipment and appurtenances associated with Grantee's oil and gas production
and transmission business upon a tract of land in Garfield County, State of Colorado, described as
follows:
Township 6 South, Ranne 94 West 6th P.M.
Section 13: A tract of land in the NE1 describe as beginning at a point in the NE'/
of Section 13, T. 6 S., R. 94 W., 6th P.M. which bears S09°01'22"W
1491.82 feet from the northeast corner of said section (being a set
marked stone); thence S01°06'45"W 616.13 feet; thence S73°00'E
31.56 feet; thence N88°53'15"W 238.71 feet; thence N01°06'45"E
626.13 feet; thence 588°53'l5"E 268.71 feet to the point of beginning.
Basis of bearings is the east line of the SEY of Section 21, T. 6 S.,
R.93 W., 6th P.M., which is assumed from G.L.O. information to
Bear north. Containing 3.859 acres, more or less.
together with the right of ingress and egress to and from same.
IT IS MUTUALLY UNDERSTOOD AND AGREED BETWEEN THE PARTIES AS
FOLLOWS:
1. Grantee shall be responsible for all costs and expenses of effecting compliance with all
Garfield County zoning regulations to permit the Grantee's intended use of the tract of land
described above. Grantor agrees to cooperate fully with Grantee's efforts to effect
compliance with local and state laws and regulations applicable to Grantee's use of the
premises including, but not limited to, the procurement of a special use permit from the
Board of County Commissioners of Garfield County, Colorado.
2. Grantee agrees to maintain its equipment in a safe condition and agrees to indemnify and
hold Grantor harmless for any damages to persons, personal property and real property
caused by Grantee's operations on the premises.
3. The rights granted herein may be assigned in whole or in part. Any such assignment shall
relieve Grantee of any liability or obligation to Grantor created by this grant of easement.
- /r
4. Upon request by Grantor, the surface facility easement herein granted shall terminate and
all rights thereunder revert to Grantor, when the surface facilities located thereon have not
been used by Grantee for a period of one (1) year except when non-use is caused by acts or
circumstances beyond the control of Grantee.
5. Upon the termination of the Grant, Grantee shall have the right to remove all equipment and
structures upon the premises.
6. This grant of easement shall be binding upon the parties hereto, their heirs, successors and
assigns.
7. This easement is for the modification of an existing facility and the installation of additional
facilities on the tract of land described above.
IN WITNESS WHEREOF, Grantor and grantee have executed this easement effective this 1st day
of October, 1996.
GRANTOR GRANTEE
W. F. Clough Southeast Piceance Pipeline Joint Venture, by
SOCO Gas Systems, Inc., its Operator
By: David M. Posner
as President of SOCO Gas Systems, Inc.
STATE OF COLORADO
COUNTY OF GARFIELD mm�� D�
The foregoing instrument was acknowledged before me this 2 day of tJ
1996, by W. F. Clough.
WITNESS my hand and official seal-����7� "
My Commission Expires:
_7_rj 7 Notary Public
Malek SNYD:R C:!_ COFPORATION
43J 7tn St.: -_'..::t
Cone 1230
Rifle, Colorado 81650
STATE OF COLORADO
COUNTY OF DENVER
The foregoing instrument was acknowledged before me this 7A.. day of pecterooL.,
1996, by David M. Posner as President of SOCO Gas Systems, Inc.
WITNESS my hand and official seal.
My Commission Expires:
/0-7-97
Notary Public
ine rk . L. GU'%t
SNYDER OIL CORPORATION
400 7th St. South
Suite 1200
Rifle, Colorado 81650
481187 B-949 P-841 • 08/. 95 10:29A PG 1 OF 3 I DOC NOT
•MILDRED ALSDORF GARFIFO COUNTY CLERK AND RECORDER 16:00
RIGHT-OF-WAY GRANT
(ROADWAY)
KNOW ALL MEN BY THESE PRESENTS:
That the undersigned, W.F. Clough, P.O. Box 686, Rifle, CO 81650, hereinafter called
Grantor, the owner of the real estate hereinaftet described, for Ten Dollars and other valuable
consideration received, does hereby grant, bargain, sell, convey and warrant unto Snyder Oil
Corporation, hereinafter called Grantee, its successors and assigns, a non-exclusive right-of-way
and easement in and across the following described real estate in Garfield County, Colorado, to
wit:
Township 6 South, Range 94 West, 6th P.M.
Section 13: Part of the NE/4
together with full rights of ingress and egress to and from same. For a more particular description
of the right-of-way and easement, see the attached Exhibit "A" which by this reference is
incorporated herein. This right-of-way and easement is granted for the purpose of affording the
Grantee access to said lands and to permit Grantee to occupy and utilize said real estate for
roadway purposes insofar as Grantee's activities are reasonably necessary to its current or future
oil and gas operations on the subject or adjacent lands. Such activities include, but are not limited
to such common oil industry practices as transport of drilling rigs, workover rigs, tractor trailers,
hauling drillpipe, casing and production tubing, water hauling trucks, perforation and fracture
treatment trucks, oil tankers, daily access by pumpers and meter readers utilizing standard sized
pickup trucks, and other equipment and vehicles necessary, in Grantee's opinion, to carry on
Grantee's oil and gas operating activities. Said use of the roadway shall extend to Grantee, its
employees, agents, contractors and licensees and their equipment of whatsoever. kind.
The right-of-way herein granted shall be eighteen feet in width, the centerline of which
is described in the attached Exhibit "A."
In consideration of the Right -of -Way grant, both parties agree as follows:
a. Grantor, its heirs or assigns, shall without obligation of maintenance, have the right to
use the roadway for any and all passage purposes, provided that Grantee shall not be liable for
any injury or damage to Grantor or third parties resulting from such use. Grantor's use shall not
impair or interfere. with the exercise by Grantee of any of the rights herein granted. Grantor shall
not create or permit any obstruction, building, water body, engineering works or other structure
over or on the right-of-way and easement.
b. Grantee will indemnify and hold harmless Grantorfrom any legal actions as a
consequence of Grantee's activities on said roadway.
c. Grantee does not and shall not claim at any time any interest or estate of any kind or
Return to:
SNYDER OIL CORPORATION
400 7th St. South
Sulle 1200
Rifle, Colorado 81650
"0 -
ICT
481187 8-949 P-842 08/1..,95 10:29A FG 2 OF 3
extent whatsoever in the roadway by virtue of this grant or by its use of the roadway, other than
the right-of-way and easement granted hereby.
d. All rights herein granted by Grantor to Grantee shall terminate upon the permanent
abandonment of all oil and gas associated facilities accessed by Grantee via this right-of-way and
easement.
Acceptance of this grant and the payment by the Grantee of the consideration above expressed
shall bind the parties hereto to all of the terms and conditions hereof, whereupon this agreement
shall extend to and be binding upon the parties hereto and their respective heirs, legal
representatives, successors and assigns, including any independent contractor of Grantee engaged
in operations hereunder.
EXECUTED THIS /tit DAY OF JULY, 1995.
GRANTOR:
W F Clow
W.F.Clough
STATE OF COLORADO
.COUNTY OF GARFIELD
-The foregoing instrument was acknowledged before me this /q42.1. day of July, 1995, by W.F.
Clough;
WITNESS my hand and official seal.
My Commission Expires:
t0-7-47
Notary Public
Mark- L. w,l),~
'/oo -ja 6/ 5au%, 5uife Ileo
EifIe, Co f/s6o
970- &ZS- gzol
Return to:
SNYDER OIL CORPORATION
400 7th St. South
Suite 1200
Rifle, Colorado 81650
LETTER OF AUTHORIZATION
I, W. F. Clough, 300 East 5th Street, Rifle, Colorado 81650, as surface owner of the lands
described below, in accordance with an Easement Grant for Surface Facilities dated effective
October 1, 1996, from W. F. Clough to Southeast Piceance Pipeline Joint Venture, hereby authorize
Southeast Piceance Pipeline Joint Venture, 1625 Broadway, Suite 2200, Denver, Colorado 80202,
to submit an Application for Special/Conditional Use Permit to install, operate, maintain and modify
a natural gas compressor and related facilities on the following described land in Garfield County,
Colorado, to wit:
Township 6 South, Range 94 West. 6th P.M.
Section 13: A tract of land in the NE'/< describe as beginning at a point in the NE'/.
of Section 13, T. 6 S., R. 94 W., 6th P.M. which bears S09°01'22"W
1491.82 feet from the northeast comer of said section (being a set
marked stone); thence Sol°06'45"W 616.13 feet; thence S73°00'E
31.56 feet; thence N88°53'15"W 238.71 feet; thence N01 °06'45"E
626.13 feet; thence S88°53'15"E 268.71 feet to the point of beginning.
Basis of bearings is the east line of the SE'/. of Section 21, T. 6 S.,
R.93 W., 6th P.M., which is assumed from G.L.O. information to
Bear north. Containing 3.859 acres, more or less.
Dated this 1st day of October, 1996.
W. F. Clough
01-8 ro e.T.eb/e &I,)/ - t
APPLICATION FOR AIR t-,LWI1ON EMISSION PERMIT OR ReRMJT MODIFICATION
va application most bo filled out completely mccpt far 114 and 115; othennao, appliotton will be constdcred incomplete - SEE
rSTRUCIIONS ON REVERSE SIDE. Mail completed application APENs and filing fee to:
Coronado Departatera of Malik
APCD•SS-RI
4300 Dummy Leak Drive South
7cfcpl ao< (303)693-3550
scar., ..w..........— _
Permit to be issued to:
�EILA Te2 7mv peetStea) ggsPz//c.0
. Mailing Address:
?/l0 3. /1)4bn:00414 Jam. 10b #IDS 7silfftw
Stas eo
Ztprad- 0229
a. Agent for Service (see Na. 3 on waits* kVA
b. Federal Tar Identification Number.• /72) - / 2R26,9)D
a. General Manor of Business:
9111.16/ CI -&41°-Jcg P°,e9(4143 GMSr,Vy
//
PMhilif
4b. STC Code:
/.3I/
Sb. Days per year source will
opeare: 3(pS
A. Air Pollution Source Description:e ,y
LT)'�p./I.4Q 35147-1-.4 LE/ br / r445/1 46S VQ&rid
:a. Source Location Address (lncbrde Lortaian Map):
SEG /3,--'-H
-ToeONah 90 ba ale e 9iiw aq. ?I
Of N. Talar r a.r. d. a.em res... tv-...-v`..-s-4 County:
tin IIIM Coordinates (in /an)
---- . - V
r. ESTIMATED COSTS:
la. Source, Process Equipment or Projects
. Cap. Cost $
Air Pollution Control Procedures or Equipment
M. Capital Con: $
lc. Opetming Cwt $
SSATOS _
❑ NarAir Pollution Sammi .
*Modrfiauion so Demisted San (Control Equipment added, pros change, de).
n,...:^ haste? Mb R pea mer 1r
y67,;::r9aP — as we JI 5d a5/N'
A 6/:': 1fe'.. rncch...e ,o •rf.E
,e0f4.r.'b OM3re to otia LE less
❑' 1Yanrfe of Ownership.- 3Y.Wimdf1 m:
❑ Existing Soutar not permitted (Include Date of San Starrap):
❑ other.
Projected Dates for Coastradian to
Ob. Begin: g -/5-y1, st.End: S -)5-4G
red Sousa Startup Date:
8d. 5-96
9.- Enclare deeds so time ADEN FBJNG FEES. One APEN should be filed for each
' NOM .dd;+tonal proaaring fes Maui also be paid prior to permit issuance.
/ APENS 0 $100.00 per ADEN : $ Jec) -
amnion point
10. SIGNAIVRE OF LEGAILr4�3 ' 'a ON iZ+QI Vendor or
Equipment Manufaaurcr) I �� II
1
11a_ Date Signed:
6-v-96.
1M. Telephone No.:
(30•09e/7-94-4
12 Type or Printmune and official title of person signing item 10.
Sarr'�. 4a/lerrE "Asmier vitioNA9
13. Check appropriate box if you cant:
a. 0 Copy of preliminary analysis condoned by Division
b. 0 To review a draft of the permit prior to issuance?
flans r.+.. r+
FIRE CONTROL MEASURES
RIFLE COMPRESSION SITE
General
• All project personnel are instructed as to:
Fire danger for the day
Location of fire control equipment
Proper operation of fire control equipment
Emergency procedures and how to call for additional resources
Welding Operations
• A minimum of one person is dedicated to act as a fire watch during welding operations
with a fire extinguisher at hand.
Welding shields are used during grinding operations to prevent sparks from leaving the
work areas and igniting vegetation.
Water trucks are used to wet down ground and nearby vegetation, as conditions dictate.
At the close of each day, welding personnel inspect the area of welding activities for any
smoldering debris and any conditions conducive to fires.
Communications
• All SOCO vehicles are equipped with cellular communications on board
In the event of a fire
• In the event of a fire, all personnel and appropriate equipment on site will be committed
to its containment and control
• The BLM and appropriate fire authorities will be notified immediately.
• Direction of fire control efforts will be transferred to appropriate fire fighting agency
personnel upon their arrival on site.
September 26, 1996
Mr. Mark Wilson
Snyder Oil Company
400 7th Street South, Suite 1200
Rifle, Colorado 81650
RE: NOISE ASSESSMENT, PROPOSED RIFLE
COMPRESSION FACILITY EXPANSION
Dear Mr. Wilson:
L ngineering
dynamics
FAX PAGE 1 OF 2
1-970-625-4636
Voice: 1-970-625-4209
Engineering Dynamics, Inc. has completed the noise assessment for the proposed
expansion of the Rifle Compression Facility, located near Rifle Colorado.
Referenced in this report is EDI's report dated July 5, 1995; which was the noise
assessment report for the existing facility.
1.0 Background
The existing site utilizes one engine/compressor set; a Waukesha 7042 GL
Engine, an Ariel JGK-4 Compressor, with J-11 Air Cooled Exchangers. The
proposed addition is to add one Caterpiller 3516 Engine with an Ariel JGE-
4 Compressor.
2.0 Existing Noise Levels
In EDI's report dated 7-5-95, the nearest receivers were identified, and
noise levels at these receivers was calculated. Table 1 below is a
reproduction of Table 2 from the 7-5-95 report, that identifies the
receiver, distance to the receiver and calculated A -weighted Sound
Pressure Levels (SPLs) at the receiver.
Table 1: Calculated A -weighted SPL's at Nearest Receiver
Receiver Distance A -weighted
Identification Feet SPLs
Nearest Property Line 80 71
Duran Residence 5000 35
Mobile Home Park 4300 36
Aside:
SPLs are measured in units of dB, which is defined as a Base,
logarithmic scale. Noise from two sources, that are close
together in relation to the distance the noise is being
measured at, are added together via Equation (1) below.
SPL,o,„ = 10 * L0010(10"w" + 10SPU/1D) (1)
Table 2 below shows the resulting noise level from adding two
noise sources together.
Table 2: Additive SPLs
Source 1 Source 2 Resulting
Level Level Level
40.00 dB(A) + 60.00 dB(A) = 60.04 ds(A)
40.00 dB(A) + 50.00 dB(A) = 50.40 dB(A)
40.00 dB(A) + 45.00 d8(A) = 46.20 dB(A)
40.00 dB(A) + 40.00 dB(A) = 43.00 dB(A)
11-
3925 south kalamath street
englewood, colorado 80110
r.3f)3) 761-4367 • fax (303) 761-4379
1
dOk
cav
Mr. Wilson
May 31, 1996
Page 2
ngineering
dynamics
The accuracy of the numbers in Table 2 has been carried to the
2nd decimal point to show the effect of adding dB's.
Examination of Table 2 shows that adding two noise sources
that have the same noise emission levels will increase the
total noise 3 dB(A).
3.0 Equipment Noise Levels
SPLs for the existing equipment and the proposed equipment are listed
below;
Existing Engine -Compressor Set 75 dB(A) at 50 feet.
Proposed Engine -Compressor Set 76 dB(A) at 50 feet.
The combined noise levels from both Engine -Compressor sets is 79 dB(A) at
50 feet.
4.0 Calculated Noise Levels
The results of Section 2.0 indicate that after installation of the
proposed 2nd engine/compressor site noise levels at the nearest receivers
shall increase 4 dB(A); these increased levels are show in Table 3.
Table 3: Calculated A -weighted SPL's atNearestReceiver
after Installation of Proposed Engine/Compressor Set
Receiver Distance A -weighted
Identification Feet SPLs
Nearest Property Line 80 75
Duran Residence 5000 39
Mobile Home Park 4300 40
As a point of reference: measured noise levels for residential areas,
similar to those near the compressor site, along I-70 in the Rifle area,
are in the 40 to 50 dB(A) range.
4.0 Conclusions
1. The calculated noise levels at the Duran Residence and Mobile Home
Park are in the same range as the existing background noise levels.
Therefore, noise from the compressor station will be audible at
these receivers.
2. The calculated noise levels are below the State of Colorado
nighttime noise limit of 50 dB(A) for residential areas.
3. Therefore, no noise mitigation will be required for this proposed
compressor site expansion.
If you have any questions, please contact me at our Englewood office.
Sincerely,
ENGINEERING DYNAMICS, INC.
Stuart D. McGregor
Vice President
./7