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Overview of Environmental Report for Costco Wheaton Gas Station. Conclusions. Conclusions. Based on standard EPA methods, air quality impacts are far below all EPA National Ambient Air Quality Standards

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conclusions1
Conclusions
  • Based on standard EPA methods, air quality impacts are far below all EPA National Ambient Air Quality Standards
  • Risks are below de minimis levels and far below reporting levels based on strict California guidelines
  • Noise levels are far below County requirements
  • Odor issues are not significant
conclusions cont
Conclusions (Cont.)
  • Opponents of the gas station are basing opposition on the premise that EPA air quality standards are not sufficiently protective
  • Regulatory and land use decisions need to be based on objective facts and standards
  • Absent alternative, defined air quality standards at the County level, there is no other objective basis to evaluate air quality impacts other than consideration of published national standards and accepted guidelines for risk assessment
conclusions cont1
Conclusions (Cont.)
  • The impacts from the Costco gas station are low in 2013 when the station opens, and will be lower over time as enhanced motor vehicles evaporative and tailpipe controls are further incorporated into the fleet
  • Costco Wheaton gas station is relatively large in terms of sales but not large in terms of emissions relative to trend lines (see attached figures)
slide6
12 M Gallons / year Station with Vent Control at 99.7% in 2013 Similar to Smaller Stations in 1980s & 1990s and Will Continue to Drop
  • This graph was based on the best estimate of when a particular emissions control strategies would be fully enacted, usually after 10 years of having the control technology first promulgated. We took the average of the original and controlled emission rate for time periods in between the 10 year block just to keep the graphs smooth and to show that technologies were being phased in over time, which is consistent with EPA methods.
slide7
12 M Gallons / year Station with Vent Control at 99.7% in 2013 Similar to Smaller Stations in 1980s & 1990s and Will Continue to Drop

Not Unprecedented: VOC emissions gasoline marketing Costco in 2013

Comparable to 1.5 M gal/year in 1987 and 3 M gal/year in 1998

slide8
12 M Gallons / year Station with Vent Control at 99.7% in 2013 Similar to Smaller Stations in 1980s & 1990s and Will Continue to Drop

Not Unprecedented: VOC emissions gasoline marketing Costco in 2020 Comparable to 1.5 Mgal/year in 1997 and 3 Mgal/year in 2005

national trends in emissions downward
National Trends in Emissions: Downward

http://www.epa.gov/airtrends/aqtrends.html

overview of environmental report
Overview of Environmental Report
  • All air quality impacts are within applicable national and state standards and guidelines, evaluated:
      • Fine particulates (PM2.5)
      • Carbon monoxide (CO)
      • Nitrogen Dioxide (NO2)
      • Volatile Organic Compounds (VOCs)
  • Odor and noise impacts minimal
overview
Overview
  • Submitted initial environmental report: July 2012
  • September 2012 met with Kensington Heights consultant: Dr. Henry Cole
  • Developed modified protocol including comments from Dr. Cole
  • Final report shows modeling results for Costco sources based on consensus approach
  • Interpretations may differ, but basis for concentrations for modeled incremental Costco sources are drawn from a common protocol
benefit to reviewers on achieving consensus of modeling methods
Benefit to Reviewers on Achieving Consensus of Modeling Methods
  • Complex modeling treatments are based on consensus methods to address incremental Costco sources
  • County staff and hearing examiner can focus on interpretation of results
not implying consensus on all issues
Not Implying Consensus on All Issues
  • Differing interpretations of fine particulates can be supported from common modeling results
  • Dr. Cole requested broader scope of modeling other operations at the mall and beyond - - (but conservatively addressed through background) - - alternative background treatments can be considered based on common modeling results
methods
Methods
  • Air quality analysis
  • Noise
  • Odors
air quality analysis refinements after initial report july 2012
Air Quality Analysis – Refinements After Initial Report July 2012
  • Modeled with updated (minute-resolved) meteorological data using EPA AERMOD software (Dr. Cole Request)
  • Also conducted confirmatory modeling with CALPUFF dispersion model to more explicitly account for terrain effects (Dr. Cole Request)
  • Added “major spills” emission category (Dr. Cole request)
  • Increased queuing assumptions and degree of conservatism in source based on resident concerns (Costco refinement)
  • Increased conservatism in modeling based on assuming lower surface roughness conditions (2x increase in conservatism) (Costco refinement)
  • Updated vehicle emissions to account more accurately for emissions controls (Costco refinement)
summary of conservative assumptions
Summary of Conservative Assumptions
  • Maximum peak traffic counts were used for all averaging times (very conservative) - - overstates (applies to Ring Road and Mall)
  • Assumed 90 percent of cars entering mall park at Costco lots and used peak traffic into mall for all analysis of parking lot emissions (applies to traffic going South at #16 and #20)
  • Used EPA conservative background method of assuming highest regional value for each averaging time occurs all the time (and corresponds with every peak modeled value)
  • Double counted some sources when modeling roadways and using conservative background contribution
summary of conservative assumptions cont
Summary of Conservative Assumptions (Cont.)
  • Used very conservative (overstated) background concentrations (maximum 2009-2011) - - e.g. used 12.1 µg/m3 for annual fine particulates - -(rather than annual averages per EPA methods)
  • As requested, refined annual average fine particulates to 10.8 µg/m3 to more accurately represent 2013 and beyond - - overly conservative considering trend lines established by Washington Council of Governments (Requested by Parks and Planning Staff)
  • Increased emission factors from queuing by 2.5-fold versus previous report to resolve ambiguity (and increase conservatism) (Costco Refinement)
  • Increased queue lengths, which were subsequently confirmed in January 2013 study at comparable Sterling gas station (Costco refinement)
  • Increased roughness of surface in model (acts to increase concentrations)

(Costco refinement)

summary of conservative assumptions 90 of all traffic to mall assumed to park in costco lots
Summary of Conservative Assumptions: 90 % of All Traffic to Mall Assumed to Park in Costco Lots

=((79+338)-67)*0.9

=((40+185)-48)*0.9

=((30+190)-61)*0.9

=((312+57)-80)*0.9

  • Assumption of 90 percent of cars entering mall parking intersections at Costco lots and use of peak traffic into mall for all analysis of parking lot emissions were clearly shown in Emission.xls spreadsheet provided to opposition - - no basis in fact for stating ignored other sources at the mall - - see Slide 58.
general layout of costco sources
General Layout of Costco Sources

Main Report Figure 1-5: Costco Gasoline and Warehouse Area Sources (in red)

east side parking area for costco
East Side Parking Area for Costco

Main Report Figure 1-6: East Parking Lot Volume Source (in red)

layout of gas station operations in model
Layout of Gas Station Operations in Model

Main Report Figure 1-4: Costco Gasoline and Warehouse Point Sources (in red)

example of intersection modeling
Example of Intersection Modeling

=Queue

=Road Segment

University Blvd

Main Report Figure 1-7: Example of 18-Vehicle Traffic Queue Lengths at Nearby Road Intersections

assumptions for cars in queue at costco
Assumptions for Cars in Queue at Costco
  • Assumed 40 cars maximum 1-hour; 20 cars maximum 8-hours, and 10 cars for average over typical 15 hour operational period
  • Costco conducted study at Sterling (same design) January 11-12, 2013; ±7% annual sales per 2012, factored 8-hour and annual for sales difference (13.9 mm / 12 mm gallons)
  • Results
  • CO 8-hour 28% standard model; 32% if assumption refined per results
  • Could increase queue assumptions four-fold or higher and still not approach standards
background treatment
Background Treatment
  • Conservatively used highest measured 2009-2011 for all modeled locations.
  • Overstates background relative to what would be expected in 2013.
  • January 2013, Parks & Planning staff requested that PM2.5 annual background be updated to more accurately reflect current conditions and to maintain compatibility with Washington Council of Government’s recommendation of 10.8 µg/m3.
  • By ~ 2014 when station is open, trend suggests that background will be < 10.8 µg/m3.
treatment of background concentrations is a standard procedure in modeling for epa or mde
Treatment of Background Concentrations is a Standard Procedure in Modeling for EPA or MDE
  • Defined Term in EPA Guideline on Air Quality Modeling: as including: “(1) natural, (2) nearby sources other than the one(s) currently under consideration, and (3) unidentified sources.”
  • By way of clarification, EPA specifies that “all sources expected to cause a significant concentration gradient in the vicinity of the source or sources under consideration for emission limit(s) should be explicitly modeled”
  • Per above, Costco has modeled all sources with potential for causing significant gradients at the Costco gas station source:
    • Costco gas station operations (fueling, spillage, delivery)
    • Ring Road
    • Costco warehouse
    • Major nearby roadways (University, Viers Mill, Georgia Ave)
    • Costco parking lot and parking garage
actual trend in pm 2 5 measured concentrations background
Actual Trend in PM2.5 Measured Concentrations (Background)

This figure was produced from using the raw annual average daily data from Rockville, Beltville, and Arlington accessed from: http://www.epa.gov/airquality/airdata/ad_data_daily.html.

This data included all monitoring locations at each site where annual averages were computed and then a 3-year running averages was used to simulate the NAAQS.

For example, the 3-year running averages for 2010 is the annual average of 2008, 2009 and 2010.

Supplemental Report Figure 4.2: Trends in PM2.5 Concentrations Based on Rockville, Beltsville, and Arlington Monitoring Sites (three-year running averages from 2005 through 2012)

actual trend in pm 2 5 measured concentrations background compared to naaqs
Actual Trend in PM2.5 Measured Concentrations (Background) Compared to NAAQS

Highest by

2012 is 10.8 µg/m3

US EPA started regulating PM2.5 in 1997 where NAAQS were 15µg/m³

annual pm 2 5 design value background concentrations from washington council of governments
Annual PM2.5 Design Value Background Concentrations from Washington Council of Governments

Supplemental Report Figure 4.3: Annual PM2.5 Design Value Background Concentration from Washington Council of Governments

importance of dose national ambient air quality standards based on defining acceptable dose
Importance of Dose: National Ambient Air Quality Standards Based on Defining Acceptable Dose
  • Air pollution does not create adverse health affects at all concentrations
  • EPA defines acceptable concentrations (dose) with a reasonable margin of safety to protect the most sensitive members of the population
  • Asthmatics and children are specifically identified in the Clean Air Act sensitive subpopulations to be protected
  • The Costco Wheaton gas station, modeled using standard EPA methods, is well below all EPA standards
detailed concentration plots and other detailed tables available in report and on slides as needed
Detailed Concentration Plots and Other Detailed Tables Available in Report and on Slides as Needed
  • Presentation presents overview for key locations: closest residence, Kenmont Swim and Tennis facility, and the Stephen Knolls School; detailed concentration aerial overlay plots are available in project reports.
  • Overall modeled concentrations are shown in presentation, but contributions from each source is available as needed to support discussion
slide36

Summary Table Showing Modeled Rural Concentrations at Pool and School Compared to Average Background Standards (µg/m3) Based on Conservative Rural Land Use (overstates close-in locations)

perspective annual average pm 2 5 concentrations g m 3
Perspective: Annual Average PM2.5Concentrations (μg/m3)

Urban Concentrations (µg/m³)

Rural Concentrations (µg/m³)

Update to Supplemental Report Figure 3.5 based on Section 4.2 analysis of background values in the Supplemental Report.

perspective maximum predicted 8 hour co concentrations g m 3
Perspective: Maximum Predicted 8-hour CO Concentrations (μg/m3)

Supplemental Report Figure 3.4: Maximum Predicted 8-hour CO Concentrations (μg/m3) for the Closest Residence, the Stephen Knolls School, and the Kenmont Swim and Tennis Center Special Receptors

perspective predicted annual average no 2 concentrations g m 3
Perspective: Predicted Annual Average NO2 Concentrations (μg/m3)

Existing: contains a small 3-7% incremental vehicle contribution from all roads

[Note: Background for Annual Average NO2 has been updated to 6.8 μg/m3 (see Section 4.0 of Supplemental Report)]

Supplemental Report Figure 3.6: Predicted Annual Average NO2 Concentrations (μg/m3) for the Closest Residence, the Stephen Knolls School, and the Kenmont Swim and Tennis Center Special Receptors

noise
Noise
  • Updated noise modeling to account for relocation of gas station operations
  • Noise levels far below County acceptable levels
  • Maximum modeled (LDN = 54.3 dBA) versus County

Ordinance of 65 dBA and background of 53 dBA.

  • Maximum values below Day / Night noise thresholds
odors
Odors
  • Supplemental report: 2.6% time closest homes to SSW and 4.9% SSE are upper bound estimates
  • Based on Sterling (without vent control at 99.7%)- - about half of fueling emissions expected in total in Wheaton with the planned controls.
  • Does not account for near-end of incompatibility period between on-board canister controls for vehicles and venting from vehicles to underground tank – Full Transition in MD 2-3 years
  • When rely exclusively with on-board canisters (expected by within several years) there will be 4x reduction from fueling emissions as compared to the Sterling odor study.
odors cont
Odors (Cont.)
  • With vent controls (99.7%) at Wheaton station and reliance on on-board canisters in the future, odors expected to be within the Ring Road.
perspective on odor analysis wheaton sterling
Perspective on Odor Analysis Wheaton/Sterling

Wheaton, MD

Sterling, VA

Vent

Gas Pumps

Filling

Approximate Distance from Gas Pumps / Odor Readings

Hedonic Tone

#1: 210 ft. \ -0.8

#2- 130 ft. \ -0.6

#3- 105 ft. \ -1.2

#4- 200 ft. \ -1.2

#5- 90 ft. \ -0.8

#6- 90 ft. \ -0.2

Approximate Distances from Gas Station Sources to Closest Home

Pumping Area: 290 ft.

Vent- 270 ft.

Fill 1- 260 ft.

Fill 2-245 ft.

Fill 3- 230 ft.

risk assessment most useful as relative risk comparison not an indication of absolute risk
Risk Assessment Most Useful as Relative Risk Comparison - - Not an Indication of Absolute Risk
  • CARB 10 in a million notification level is a risk management tool
  • For relative comparison, EPA modeling applicable for Montgomery County shows ~ 65 in a million as background risk for specific set of pollutants modeled (EPA monitoring shows 70-370 in a million for this area)
  • Based on urban modeling highest relative risks from Costco gas station operations is < 1 in a million
slide47
Urban VOC Annual Incremental (Emissions per protocol without considering reduction for canister controls on motor vehicles)
slide48
Urban VOC Annual Incremental (Emissions considering reduction for canister controls on motor vehicles
opposition positions are not supported by sound science
Opposition Positions are Not Supported By Sound Science
  • Ultrafine particulates
  • Risks at school and pool
  • Long-term monitoring of air quality / meteorology
  • Broad modeling of sources in area versus standard EPA background treatments
  • Alleged terrain complications
  • School siting guidance (CARB and EPA)
ultrafine particulates
Ultrafine Particulates
  • Maximum annual average fine particulates at closest residence is 0.005 µg/m3.
  • If MOVES was available maximum may increase to ~ 0.01 µg/m3.
  • New standard is 12 µg/m3; background is 10.8 in 2013, and less by 2014 and beyond
  • EPA and expert panel (CASAC) reviewed literature and conclusion: new standard protective of most sensitive with adequate margin of safety
  • EPA defines insignificant contributions to fine particulates for this region as 0.3 µg/m3 , i.e. Costco’s maximum impact is 30 lower than EPA’s defined level for insignificant contributions if maximum Costco impacts are doubled
  • There is no objective or rational basis for concern based on ultrafine particulates contributions from the Costco gas station
diesel emissions from 4 costco clean diesel delivery trucks day do not present a significant source
Diesel Emissions From 4 Costco Clean Diesel Delivery Trucks / Day Do Not Present a Significant Source
  • Four clean diesel trucks per day to gas station
  • “The emissions of particulate mass in NTDE (clean diesels) are substantially lower (less than 1%) than those emitted from 1988 engines.”1
  • “In fact, the nanoparticle number concentration emissions contained in NTDE are well below typical urban ambient air concentrations, and amount to a 10,000-fold reduction when compared against older diesel engines not equipped with DPFs (Barone et al., 2010).”1
  • “Most importantly, NTDE is virtually free of the elemental carbon particles found in TDE”1
  • Diesel emissions from the Costco gas station are not significant

1R.O. McClellan et al. / Regulatory Toxicology and Pharmacology 63 (2012) 225–258

ultrafines are much higher in homes due to inside sources during described activities
Ultrafines Are Much Higher in Homes due to Inside Sources (during described activities)

Glystsos, T. et. al., “Characterization of Particulate Matter Concentrations During Controlled Indoor Activities,” Atmospheric Environment,

44 (2010) 1539-1549.

slide54

Highest Levels of Ultrafine Particles and Most Toxic are Not Direct Emissions But Photochemically Produced in Atmosphere on a Regional Basis

Counts off-peak

but after

Photochemical

Reactions in

atmosphere

Direct counts during

Rush hour period

Varma, V. et. al., “Redox Activity of Urban Qauasi-Ultrafine Particles from Primary and Secondary Sources, Atmospheric Environment, 43 (2009) 6360-6368.

ultrafine particulates fast food restaurants common commercial source costco gas station
Ultrafine Particulates & Fast Food Restaurants: Common Commercial Source >> Costco Gas Station
  • Fast-food restaurants are common commercial facilities permitted in Montgomery County

“Restaurants, especially fast food and grill outlets that conduct a lot of frying, are also thought to contribute to UFP concentrations. For example, measurements from the California Children’s Health Study reported high UFP levels (similar to those near major freeways) at a monitoring site next to a fast-food restaurant (38) while a study of UFP concentrations in Manchester, England suggested high restaurant density as a predictor of elevated UFP concentrations.”

“A Land Use Regression Model for Ultrafine Particles in Vancouver, Canada » , Rebecca Abernethy, B.Sc., The University of British Columbia, 2008 a thesis submitted in partial fulfillment of the requirements for the degree of master of science in the faculty of graduate studies (Occupational and Environmental Hygiene).

risks at school and pool are insignificant
Risks at School and Pool Are Insignificant
  • Important omission when discussing the school and pool: dose
  • National Ambient Air Quality Standards are developed to protect the most sensitive subpopulations with a reasonable margin of safety, and specifically children and asthmatics
  • All standards and guidance are met with wide margins at the school and pool
long term monitoring of air quality and meteorology
Long-Term Monitoring of Air Quality and Meteorology
  • Even large industrial sources are not required to conduct the extensive air quality and meteorological monitoring proposed by opponents to the gas station
  • Standard practice would be to use existing meteorological data for a setting such as this and to conservatively use regionally available air quality data to address background contributions
  • Unlikely to be one gas station in the U.S. that has conducted extensive pre or post construction air quality and meteorological monitoring as requested by the opposition
  • EPA recommends three years of air quality data to ensure a stable data set, which obviously is inconsistent with the permitting process for facilities of this nature - - reason for EPA use of regional data
slide58
Modeling of All Parking Lots and Other Loading Docks (90 % cars peak hours to Costco lots: very conservative)
  • Costco has most likely conducted the most extensive air quality modeling analysis of any gas station in the U.S.:
    • All gas station operations including (filling of underground tanks, filling of motor vehicles, spills, queuing, ingress / egress)
    • Ring Road
    • Costco warehouse parking lots and loading dock
    • All major nearby roadways and intersections (University, Viers Mill, and Georgia Avenue)
  • The results would be substantially lower if it were feasible to model all sources of air pollution within and beyond the mall and not use the highly conservative background approach recommended by EPA (and followed here)
slide59
What if Include Other Loading Docks Included and Unrealistically Assume Same Parking Rates as Costco Throughout the Mall

Giant

Target

Costco

Sears

close up view of new loading docks added
Close-Up View of New Loading Docks Added

Target Loading Dock

Other Mall Loading Docks

=New Conservative Loading Dock Locations Added

slide61
What if Include Other Loading Docks Included and Unrealistically Assume Same Parking Rates as Costco Throughout the Mall (Cont.)
alleged terrain complications no basis in fact to suggest this is a significant issue
Alleged Terrain Complications - - No Basis in Fact to Suggest This is a Significant Issue
  • No regulatory agency in the country would require specialized micrometeorological study or specialized modeling because of the presence of a small drop in terrain as occurs here
  • This topic was addressed during the protocol discussion, supplemental modeling analysis was conducted as requested by the opposition, which showed terrain issues to be insignificant
  • There is no scientific basis to allege that the presence of the hill would result in exceedances of any accepted air quality standard
  • The allegation in fact is inconsistent with the terrain slope, the vegetation cover, the surface material at the mall, the hours of operation of the school, and all other factors considered
  • See supplemental PowerPoint.
slide63
Percent of Possible Hours That Could Even Potentially Have the Gravity Flow Conditions is Very Small
  • Gravity flow (redirection towards residential area to the south) of emissions from Costco gas station can only occur when all of the following conditions occur:
    • When the gas station is open
    • When flow is from the southerly direction
    • During nighttime conditions (1 hr < sunset through 1 hr > sunrise)
    • Non-overcast conditions
    • Light wind speeds, such as ≤ 7 mph
  • Review of 5 years of meteorological data shows that all of the above conditions occur ~ 4 percent of the time - - - maximum potential
  • See next slide for unlikely gravity flow impacts toward community even when all conditions are aligned (i.e. the 4 percent described above)
alleged gravity flow concern is inconsistent with facts
Alleged Gravity Flow Concern is Inconsistent with Facts
  • Terrain slopes up towards Ring Road (not down)
  • Flow if deflected from screening wall would flow to the East, which slopes towards the North and away from the neighborhood
  • The alleged impacts at the school are incorrect since the school is open 8:55 AM to 3:10 PM - - inconsistent with the nocturnal nature of this potential condition
  • Most of the year there is vegetation cover along the downslope towards the community which would inhibit the formation of gravity flow conditions (actual potential less than 2 percent)
school siting guidance carb and epa
School Siting Guidance (CARB and EPA)
  • Developed by California (CARB) and EPA to guide siting of new schools when site-specific air quality studies are not available
  • Based on hypothetical, unrealistic meteorological data (1 m/sec wind speed and nighttime restrictive dispersion all the time)
  • Assumes 100 percent occupancy for a lifetime
  • Does not consider prevailing flow relative to offsite locations, control equipment at the station, etc.
  • Does not consider 99.7% vent control at Costco Wheaton
  • Both EPA and CARB indicate that generic guidance is overruled by site-specific analysis (see next slide)
school siting guidance
School Siting Guidance

CARB

  • Costco has conducted site-specific analysis that overrides simple screening methodology

EPA

slide67
Attempts to Link Gas Station to Major Federal Environmental Requirements (that are obviously not applicable to a gas station)
  • EPA’s Conformity Rule: applies to Federal actions and of much larger size than building a gas station (“Conformity determinations are not required under this subpart for individual projects which are not FHWA/FTA projects. However, §93.121 applies to such projects if they are regionally significant” - - neither of which applies to building a gas station)
  • National Environmental Policy Act (NEPA) does not apply to building a gas station: (Not a Federal action and not of sufficient size)
  • Prevention of Significant Deterioration (PSD) does not apply to a gas station (not a major source per PSD definition: not applicable)
changing the definition of a gas station
Changing the Definition of a Gas Station
  • Costco is proposing to build a gas station to sell gasoline (only) to the public
  • “The emissions from the gas depot resemble emissions from a small factory . . “ Larry Silverman 4/4/13
  • “Do the Clean Air Act (CAA) National Ambient Air Quality Standards (NAAQS) guarantee that the regional gasoline distribution center proposed by Costco is safe?”Larry Silverman 4/4/13
reduction in energy consumption and greener environment for county
Reduction in Energy Consumption and Greener Environment for County
  • Business model of Costco results in more combined trips (combined shopping and gasoline purchase)
  • Reduced driving emissions through centralization of shopping
  • Reduced driving for Costco members that now drive outside of Montgomery County to purchase gasoline
  • Greater controls on Costco gas stations as compared to alternatives:
    • Arid permeator reduces vent emissions 99.7% versus standard gas station
    • Attendant always on duty to respond to spills and to take corrective action