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Home My WebLink AboutMINUTES - 07221997 - C68 TO: BOARD OF SUPERVISORS Contra FROM: HARVEY E. BRAGDON Costa DIRECTOR OF COMMUNITY DEVELOPMENT "" " County DATE : July 22, 1997 SUBJECT: Ratification of the Zoning Administrator's Decision Regarding Shell Oil Company's Compliance with Conditions of Approval #35B (LUP 2009-92) SPECIFIC REQUEST (S) OR RECOMMENDATIONS) & 'BACKGROUND AND JUSTIFICATION RECOMMENDATIONS 1 . Ratify the Zoning Administrator' s decision that Shell Oil Company has complied with Condition 35B for the Hydrogen Plant No . 3 . FISCAL IMPACT None. BACKGROUND/REASONS FOR RECOMMENDATIONS When the Board of Supervisors approved the Land Use Permit for Shell Oil Company' s Clean Fuels Project (County LUP #2009-92) , the Board specified that the Zoning Administrator' s decision regarding several conditions of approval be placed on the Board' s consent calendar for ratification. As directed by the Board at the October 4, 1994 meeting, the County Zoning Administrator decisions discussed herein have been placed on the Zoning Administrator' s agenda for July 21, 1997 . Any comments received at the meeting will be forwarded to the Board. CONTINUED ON ATTACHMENT: XX YES SIGNATURE RECOMMENDATION OF COUNTY ADMINISTRATOR RECOMMENDATION OF BOARD COMM TTEE APPROVE OTHER SIGNATURE (S) : ACTION OF BOARD ON July 22, 1997 APPROVED AS RECOMMENDED X OTHER VOTE OF SUPERVISORS I HEREBY CERTIFY THAT THIS IS A X UNANIMOUS (ABSENT TRUE AND CORRECT COPY OF AN AYES: NOES : ACTION TAKEN AND ENTERED ON THE ABSENT: ABSTAIN: MINUTES OF THE BOARD OF SUPERVISORS ON THE DATE SHOWN. Contact: Debra Sanderson (510/335-1208) ATTESTED July 22, 1997 cc: Community Development Department (CDD) PHIL BATCHELOR, CLERK OF Health Services Department : Haz Mat THE BOARD OF SUPERVISORS Shell Oil (via CDD) AND COUNTY ADMINISTRATOR BY DEPUTY DRS\aw J:\aw\7-22sh1.bo Ratification of the ZA's Decision Regarding Shell Oil Co. Compliance with COA #35B (LUP 2009-92) July 22, 1997 Page Two Condition of Approval #35 - Compliance with Noise Standards : Permit Condition #35A requires the submittal of detailed noise level calculations to demonstrate that the unit to be constructed will comply with the noise performance standard (77 dBA when measured five feet above the ground and 100 feet from the equipment) . Permit condition #35B requires that once a unit is operational, additional noise monitoring be completed to verify that noise from the operating unit meets the standard. As discussed during Shell ' s Annual Compliance Hearing, noise from the new Hydrogen Plant #3 did not initially meet the County's Noise Performance Standard for this project. Consistent with the approved Noise Monitoring Protocol, Shell has been working on options to reduce this noise to acceptable levels. Shell has installed two types of noise controls - a noise control barrier on the west and south sides of the Pressure Swing Absorption Skid (an element of the Hydrogen Plant) ; and thermal/acoustical insulation of a fuel (purge) line. After installing these control measures, a qualified acoustical expert took new noise measurements and prepared a new noise monitoring report. Staff has evaluated the new noise monitoring report, submitted by Shell on June 12, 1997 , and finds it consistent with the noise monitoring protocol previously approved for this project. Staff concurs with the report, which demonstrates that the Hydrogen Plant No. 3 now meets the noise performance standard for this project. =611,-Iti VAN Shell Martinez Refining Company P.O. Box 711 Martinez,California 94553-0071 Telephone: (510)313-3000 v June 12, 1997 Ms. Debbie Chamberlain Contra Costa County Community Development Department. Administration Building, North Wing, 4th Floor 651 Pine Street 43 Martinez, CA 94553-0095 ca Dear Ms. Chamberlain, SUBJECT: SHELL OIL COMPANY CLEAN FUELS PROJECT OPERATIONAL NOISE MONITORING REPORT FOR HYDROGEN PLT. 3 (COUNTY FILE NUMBER 2009-92) In compliance with the Clean Fuels Project Land Use Permit Condition # 35B and Mitigation Measure 10-4, we are submitting operational noise measurements for Hydrogen Plant 3. The report is consistent with the Monitoring Protocol previously approved and demonstrates that these elements comply with the requirements defined in Condition #35A. We understand, that according to the Land Use Permit Condition # 4, the Zoning Administrator's decision regarding this submittal shall be placed on the Consent Calendar of the Board of Supervisors' meeting for ratification. If you have any questions regarding this information, please contact me at (510) 313-3695. Very truly yours, CVLeAL41� C-111--t. E. T. Swieszcz, Staff Engineer Environmental Affairs bc: M. R. Reed - Mgr., Process Eng. Steve Tirrell, LPO - Trailer C Mark Brown, Proc Eng - CFP Trailer A ETS File ECD Clean Fuels Binder Vol 3 OPERATING NOISE MEASUREMENT REPORT FOR HYDROGEN PLANT NUMBER 3 SHELL MARTINEZ MANUFACTURING COMPLEX CLEAN FUELS PROJECT - BECHTEL JOB NO. 22500 Report Prepared By: Date: Noise Measurement Made By: On: Frank H. Brittain,Ph. D., Member INCE f , Frank H. Brittain,Ph. D.,Member INCE Principal Engineer, Principal Engineer, Noise Control Engineering, Noise Control Engineering, Bechtel Corp. Bechtel Corp. SHELL MARTINEZ MANUFACTURING COMPLEX CLEAN FUELS PROJECT-BECHTEL JOB NO.22500 OPERATING NOISE MEASUREMENT REPORT FOR HYDROGEN PLANT NUMBER 3 1. INTRODUCTION Measurements of operating noise from Hydrogen Plant Number 3 of the Clean Fuels Project at Shell Martinez Refinery were made on 10 June 1997. The purpose of the noise measurements was to demonstrate that Hydrogen Plant Number 3 meets the noise levels specified in Condition No. 35A of the Contra Costa County's Land Use Permit No. 2009-92. These measurements were made according to the Shell Martinez Clean Fuels Project Protocol For Verifying Noise Emissions From Individual Process Units, dated 27 April 1994 (hereafter called the Protocol) that was approved by the Contra Costa Board of Supervisors on 14 June 1994. These measurements show that Hydrogen Plant Number 3 complies with the County's noise performance standard of 77 dBA at 100 feet from equipment and 5 feet above grade on all four sides of the Plant. The 77 dBA limit is defined in the Protocol to be an L50, the A-weighted sound pressure level that is exceeded 50 percent of the time during a sampling period. 2. MEASUREMENT LOCATIONS Four to six measurement locations were selected for each of the four sides of the Plant. These locations are shown on Figure 1, a plot plan showing the layout of Hydrogen Plant Number 3 (HP-3). All measurements were made 5 feet above the grade of HP-3. Noise levels around HP-3 were significantly affected by noise from adjacent Units, and measurements on three sides were made at substantially less than 100 feet from the Equipment Perimeter. The Equipment Perimeter is a straight line along each side of the Plant so that the equipment on that side just falls inside the line. Due to the shape of the plant, the Equipment Perimeter has the shape of a trapezoid. Measurements were made at the following distances from the Equipment Perimeter: Distance from Equipment Side of Perimeter Plant (feet) Comments South 40 or 45 The Distillates Hydrotreater (DHT) is south of HP-3, and there are about 70 feet between the two Equipment Perimeters. To reduce the effects of noise from the DHT, measurements were made closer to HP-3 than 100 feet. East 100 There are no Clean Fuels or other refinery Units to the east. The only noise source is I-680. noiserep.HP3 Page 1 of 7 12 June 1997 North 20 to 80 About 20 feet north of much of HP-3's north fence, there is an embankment that drops down to a parking lot. To avoid this slope and keep the microphone 5 feet above the grade of HP-3, most measurements were made just inside the fence. West 40 and 65 The Delayed Coker Unit (DCU) is located west and southwest of HP-3. The minimum distance between HP-3 and DCU Equipment perimeters is about 45 feet. Due to space limitations and noise from the DCU, measurements were made closer than 100 feet from the Equipment Perimeter. 3. INSTRUMENTATION The following instrumentation were used in making the noise measurements: o Hewlett Packard 3569A, Sound Level Analyzer with Octave Bands o Bruel and Kjaer 4134, Microphone o GenRad P42, Preamplifier o Bruel and Kjaer 4230,Acoustic Calibrator o Windscreen o Anechoic wedge baffle (see Section 6). 4. OPERATING CONDITIONS DURING MEASUREMENTS The Hydrogen Plant Number 3 was operating normally and at 99 percent of rated capacity during the measurements. The DHT and DCU were operating normally during the measurements. There was no construction during the measurements. 5. NOISE CONTROLS Noise measurements of HP-3 operating noise were made in August 1996. At that time, the measured noise levels on the south and west sides exceeded the 77 dBA noise limit by less than 1 dB, when corrected for the measurement distances. Noise levels on the east side were consid- erably below the 77 dBA limit, and when corrected for distance, noise levels on the north side met the limit. The dominant noise source that caused the limits to be slightly exceeded is the Pressure Swing Absorption (PSA) Skid. The following noise controls have recently been added to reduce noise levels on the west and south sides of HP-3: o A noise control barrier constructed of flexible blankets on the entire west and south sides of the PSA Skid. o Thermal/acoustical insulation with a layer of mass-loaded vinyl and aluminum jacket covered the part of the fuel (purge) gas line nearest the west fence of HP-3. 6. MEASUREMENTS Measurements of noise levels during operation of Hydrogen Plant Number 3 were made on 10 June 1997 by Frank Brittain of Bechtel, a member of INCE (Institute of Noise Control Engineers) noiserep.HP3 Page 2 of 7 12 June 1997 with 26 years of experience in noise control engineering. Henry Hall assisted in making the measurements. Dr. Brittain also prepared this report. Instruments used in making the noise measurements were in accordance with the Protocol. The levels measured were recorded directly on the analyzer as an L50. Instruments were calibrated both before and after the measurements. Without special provisions, operating noise from the adjacent DHT and DCU Units would signifi- cantly affect the levels measured on the west and south sides. To reduce noise from these adja- cent Units, an "anechoic wedge baffle" was used to help eliminate noise from adjacent Units. The baffle is shown in Figure 2. The microphone is positioned on the side of the baffle containing the anechoic wedges. The side of the baffle with the anechoic wedges and the microphone is placed toward the source being measured. Noise coming from the opposite side (rear of the baffle) is largely blocked by the plywood sheets to which the anechoic wedges are attached, and has little or no effect on the levels measured by the microphone. Without the anechoic wedges, noise from HP-3 would be reflected by the front face of the plywood and give erroneous readings. The anechoic wedges prevent reflections so that measured levels are more accurate. Any disturbance of the sound field caused by the baffle (reflections from the anechoic wedges and diffraction of noise from the Unit behind the baffle) will add slightly to the measured level. Thus, the measured levels will not reduce noise from HP-3, and are an accurate representation of noise from HP-3. The baffle was used for measurements at Locations 1 through 5, 15, and 16. The angle between the two halves of the baffle was 900 at all Locations. The line of sight from the microphone to the entire HP-3 was not blocked by the edges of the baffle. Since the microphone is placed 12 to 18 inches in front of the anechoic wedge tips, the angle that has unobstructed lines of sight to HP-3 is greater than the 900 angle of the baffle. 7. DEVIATIONS FROM PROTOCOL Measurements were made according to the Protocol. For reasons indicated in Section 2, meas- urements on three sides were made closer than 100 feet from the Equipment Perimeter. Noise levels measured closer than 100 feet are expected to be higher than would be measured at 100 feet, and correction for distance is allowed by the Protocol. 8. . RESULTS The measured noise levels are given in Table 1. The levels in Table 1 are A-weighted L50 sound pressure levels measured during a 5-minute period. No background noise level data are available. The results are logarithmically averaged for each side as specified in the Protocol. While correc- tion of data for background levels is permitted in the Protocol, the data in Table 1 were not corrected for background. 9. CONCLUSION Measurements were made while Hydrogen Plant Number 3 was operating normally and at full, capacity. The adjacent DHT and DCU Units were operating normally. When corrected for distance, the average noise level on each side of Hydrogen Plant Number 3 meets the County's noise performance standard of 77 dBA at 100 feet from the Equipment Perimeter and 5 feet above grade. This limit has been met at distances of less than or equal to the required 100 feet on noiserep.HP3 Page 3 of 7 12 June 1997 four sides. With the use of the anechoic wedge baffle, noise emitted by adjacent units has a negligible affect on the measured levels. noiserep.HP3 Page 4 of 7 12 June 1997 TABLE 1 Measured Operational Noise Levels for Hydrogen Plant Number 3 Side Distance Operational Sound Pressure Level in dBA Of Measurement From Corrected For Average Of Cor- Plant Location EP* (ft.) Measured Distance** rected Levels South 1 40 76.3 72.9 2 45 80.9 77.8 3 45 78.5 75.4 4 45 76.2 73.0 5 45 71.2 68.0 6 45 66.9 63.8 Logarithmic Average 73.8 East 6 100 66.9 66.9 7 100 67.2 67.2 8 100 66.0 66.0 9 100 64.1 64.1 Logarithmic Average 66.2 North 9 50 64.1 61.2 10 55 77.8 75.2 11 25 79.8 75.8 12 20 77.0 72.8 13 45 74.4 71.3 14*** 80 74.2 72.9 Logarithmic Average 73.2 West 14*** 65 74.2 72.9 15 65 75.5 73.4 16 65 77.5 75.4 1 40 76.3 72.9 Logarithmic Average 73.8 * EP is the Equipment Perimeter ** Data is corrected for distance from the measurement Location to the 100 foot perimeter *** Data at Location 14 has been corrected for distance to the north only (smallest correction) noiserep.HP3 Page 5 of 7 12 June 1997 � Z N Ny .1 -L--L-- - �- Mf I , I ' I a iIII) PT , 0 ❑i / i � 11 W I I I ® ® FRi ! 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