SPARGING VAPOR EXTRACTION AND TREATMENT SYSTEM, CONSISTING OF:
1) EXTRACTION WELLS AND DUCTS.
2) AIR SPARGING VAPOR EXTRACTION
SYSTEM, MAKE____________, MODEL NO. ______, SERIAL NO. _________, WITH A GAS/LIQUID
SEPARATOR, ____-GALLON CAPACITY.
3) THREE CARBON ADSORBERS IN
SERIES, MAKE____________, MODEL NO. _______, EACH WITH ____ POUNDS CAPACITY OF
GRANULAR ACTIVATED CARBON.
4) EXHAUST SYSTEM CONSISTING OF A
_._ HP BLOWER VENTING THROUGH A STACK, ___’- ___" DIA. X ___’- ___"
H., _____ SCFM.
A/N ______ was validated on
__/__/2000 as Class 1 to construct an underground soil vapor extraction and treatment
system, to be located at the corner of ______ Street and _______ Avenue in _______. There
is a school, ______ ______ School, located at ________ _______ Avenue, _______, CA _____,
that is within 1000 feet from the proposed equipment, and which triggers the Rule 212
public notice requirement.
The applicant initially proposed
two carbon adsorbers in series, however, has agreed to add an additional carbon adsorber
(three in series total) in acknowledging the sensitivity of a nearby school. Soil samples
indicate non-detectable concentrations of petroleum hydrocarbons, however groundwater
samples collected at adjacent monitoring wells indicate petroleum hydrocarbon
contamination. Therefore this system proposes to inject air to sparge off the VOC
contaminants away from nearby residences, to be collected by the underground vapor
extraction wells and treated in the carbon adsorbers. The source of the petroleum
hydrocarbon contamination is thought to be from a fueling and dispensing facility at the
adjacent fire station.
This control system is
estimated to be 99.75% efficient in controlling hydrocarbon emissions.
The applicant estimates that 900
mg/m3 (247 ppmv as hexane MW 86.18) of VOC can be collected in the extraction
VOC (R1) = 0.900 g/m3 x
200 cfm x m3/35.3145 cf x 60 min/hr x lb/453.593 lb
= 0.674 lb/hr x 24 hr/day
= 16.18 lb/day x 365 day/yr
= 5906 lb/yr (2.95 ton/yr)
VOC (R2) = 0.674 lb/hr x
= 0.00169 lb/hr x 24 hr/day
= 0.040 lb/day x 365 day/yr
= 14.8 lb/yr
Estimate breakthrough emissions at
first stage to be 10% (90% control) of uncontrolled emissions.
Breakthrough = 0.0674 lb/hr x
mole/86.18 lb x 379 ft3/mol x hr/60 min x min/200 ft3 x 106
= 25 ppmv as hexane
Estimated Benzene first stage
outlet concentration = 36.3 ppmv x (1-95/100)
= 2 ppmv
The applicant indicates that
the inlet contaminants are petroleum hydrocarbons and include benzene 120 mg/m3 (36.3
ppmv), ethylbenzene 130 mg/m3 (29 ppmv), toluene 300 mg/m3 (77 ppmv)
and xylenes 250 mg/m3 (55.7 ppmv). Risks are tabulated in the attached risk
assessment spreadsheet assuming an overall control efficiency of 99.75%. The results are
Benzene = 0.120 mg/m3 x
lb/453.593 x lbmol/78.11 lb x 379 ft3/lbmol x m3/35.3145 ft3
= 36.3 ppmv
Ethylbenzene = 0.130 mg/m3
x lb/453.593 x lbmol/106.17 lb x 379 ft3/lbmol x m3/35.3145 ft3
= 29 ppmv
Toluene = 0.130 mg/m3 x
lb/453.593 x lbmol/92.14 lb x 379 ft3/lbmol x m3/35.3145 ft3
= 77 ppmv
Xylenes = 0.130 mg/m3 x
lb/453.593 x lbmol/106.16 lb x 379 ft3/lbmol x m3/35.3145 ft3
= 55.7 ppmv
TOXIC RISK SUMMARY:
Compliance with the provisions of
Division 26 of the State Health and Safety Code is expected. A public notice was
distributed as required per Rule 212 (c)(1) since the equipment is to be located within
1000 feet from the outer boundary of a school.
Compliance is expected.
Compliance is expected.
Compliance is expected
Compliance with 1166(c)(3) is
REGULATION XIII - New Source Review
The requirements of 1303(a) BACT
are satisfied with carbon adsorption for volatile organic compound control. Modeling per
Rule 1303(b)(1) is not applicable to VOC’s. Rule 1303(b)(2) emission offsetting is
exempted under rule 1304 since thresholds are not exceeded.
Cancer risk is expected to be less
than one in a million for residential and commercial receptors. Acute hazard indices are
expected to be below 1.0; chronic hazard indices are not calculated since chronic hazard
compounds are not expected.
It has been determined that the
equipment will operate in compliance with all the applicable Rules and Regulations of the
Once Rule 212’s public notice
distribution has been satisfied, issue a permit to construct subject to conditions:
OPERATION OF THIS EQUIPMENT SHALL
BE IN COMPLIANCE WITH ALL DATA AND SPECIFICATIONS SUBMITTED WITH THE APPLICATION UNDER
WHICH THIS PERMIT WAS ISSUED, UNLESS OTHERWISE NOTED BELOW.
THIS EQUIPMENT SHALL BE PROPERLY
MAINTAINED AND KEPT IN GOOD OPERATING CONDITION AT ALL TIMES.
UPON COMPLETION OF THIS
OPERATION, ANY REMAINING VAPOR EXTRACTION WELLS AND DUCTS SHALL BE CAPPPED TO PREVENT
VAPORS FROM VENTING TO THE ATMOSPHERE. VAPORS SHALL NOT BE EXTRACTED FROM THE SOIL UNLESS
THEY ARE VENTED TO THE VAPOR CONTROL SYSTEM, WITH NO DETECTABLE LEAK BETWEEN THE OUTLET OF
THE BLOWER AND THE OUTLET OF THE VAPOR CONTROL SYSTEM.
AN IDENTIFICATION TAG OR
NAMEPLATE SHALL BE DISPLAYED ON THE EQUIPMENT TO SHOW THE MANUFACTURER, MODEL NUMBER AND
SERIAL NUMBER. THE TAG(S) OR PLATE(S) SHALL BE ISSUED BY THE MANUFACTURER AND SHALL BE
ADHERED TO THE EQUIPMENT IN A PERMANENT AND CONSPICUOUS POSITION.
THE MOST CURRENT CONTACT
PERSON’S NAME, COMPANY AND PHONE NUMBER SHALL BE DISPLAYED IN A PERMANENT AND
A FLOW INDICATOR SHALL BE
INSTALLED AND MAINTAINED AT ALL INLET STREAMS TO THE VAPOR CONTROL SYSTEM TO INDICATE THE
TOTAL AIR FLOW RATE IN CUBIC FEET PER MINUTE (CFM). IN CASE A PRESSURE SENSOR DEVICE IS
USED IN PLACE OF THE FLOW INDICATOR, A CONVERSION CHART SHALL BE MADE AVAILABLE TO
INDICATE THE CORRESPONDING FLOW RATE, IN CFM, TO THE PRESSURE READING.
THE TOTAL INLET FLOW RATE SHALL
NOT EXCEED 200 SCFM.
THE VOLATILE ORGANIC COMPOUND
(VOC) CONCENTRATION SHALL BE MEASURED EACH DAY DURING THE FIRST TWO WEEKS OF OPERATION AND
ON A MINIMUM WEEKLY BASIS THEREFAFTER AT THE INLET AND OUTLET OF THE FIRST STAGE CARBON
ADSORBER. THE VOC CONCENTRATION SHALL BE MEASURED USING A FLAME IONIZATION DETECTOR (FID),
PHOTOIONIZATION DETECTOR (PID), OR AN AQMD APPROVED ORGANIC VAPOR ANALYZER (OVA)
CALIBRATED IN PARTS PER MILLION BY VOLUME (PPMv) OF HEXANE (IF A CALIBRATION AGENT OTHER
THAN HEXANE IS USED IT SHALL BE CORRELATED TO AND EXPRESSED AS HEXANE).
WHENEVER THE VOC CONCENTRATION AT
THE OUTLET OF THE FIRST STAGE CARBON ADSORBER IS 25 PPMv OR GREATER AS HEXANE, OR WHEN VOC
BREAKTHROUGH HAS OCCURRED AT THE FIRST STAGE ADSORBER, THE SOIL VAPOR EXTRACTION AND
TREATMENT SYSTEM (SVE) SHALL BE IMMEDIATELY SHUT DOWN, AND THE FIRST STAGE ADSORBER
REMOVED FROM SERVICE. THE SVE SHALL NOT BE RESTARTED UNTIL THE SECOND STAGE ADSORBER HAS
BEEN RELOCATED TO THE FIRST STAGE ADSORBER POSITION, THE THIRD STAGE ADSORBER RELOCATED TO
THE SECOND STAGE ADSORBER POSITION, AND A NEW THIRD STAGE ADSORBER WITH FRESH ACTIVATED
CARBON IS INSTALLED. RECORDS OF THE SERIAL NUMBER OF EACH CANISTER OF ACTIVATED CARBON,
THE DATE EACH IS INSTALLED, THE POSITION IN THE SERIES (FIRST, SECOND, OR THIRD STAGE
POSITION), AND THE DATE REMOVED FROM SERVICE SHALL BE MAINTAINED TO DOCUMENT COMPLIANCE
WITH THIS CONDITION.
A GRAB SAMPLE SHALL BE COLLECTED
AT THE INLET AND OUTLET OF THE FIRST STAGE CARBON ADSORBER DURING THE FIRST WEEK, AND AT
LEAST ONCE PER MONTH THEREAFTER. THE SAMPLES SHALL BE ANALYZED FOR TOTAL VOC IN PPMv AS
HEXANE, AND ANALYZED FOR BENZENE, ETHYLBENZENE, TOLUENE AND XYLENES, SPECIATED IN
ACCORDANCE WITH AQMD APPROVED METHODS.
THE BENZENE CONCENTRATION AT THE
OUTLET OF THE FIRST STAGE CARBON ADSORBER SHALL NOT EXCEED 2 PPMv.
THIS EQUIPMENT SHALL NOT BE USED
TO TREAT VAPORS CONTAINING HALOGENATED COMPOUNDS, NOR ANY TOXIC COMPOUNDS LISTED IN AQMD
RULE 1401 (AS AMENDED ON 3-17-2000) OTHER THAN BENZENE, TOLUENE AND XYLENES.
THE ACTIVATED CARBON USED IN THE
ADSORBERS SHALL HAVE A CARBON TETRACHLORIDE ACTIVITY NUMBER OF NOT LESS THAN 60% AS
MEASURED BY ASTM METHOD D3467-99 OR A BUTANE ACTIVITY NUMBER OF NOT LESS THAN 23.5% AS
MEASURED BY ASTM METHOD D5228-92 (1996).
SPENT CARBON REMOVED FROM THE
SYSTEM SHALL BE STORED IN CLOSED CONTAINERS PRIOR TO REMOVAL FROM THE SITE.
RECORDS SHALL BE KEPT AND
MAINTAINED TO PROVE COMPLIANCE WITH ALL CONDITIONS ON THIS PERMIT. THE RECORDS SHALL BE
KEPT ON FILE FOR AT LEAST TWO YEARS AND MADE AVAILABLE TO AQMD PERSONNEL UPON REQUEST.