James A. Westbrook, CCM of BlueScape discusses challenges companies will face with the new 1-hour NO2 and SO2 national ambient air quality standards, and implementation of the PM2.5 standards. He provides strategies to avoid modeling requirements, or pass the stringent standards. For questions or support, Mr. Westbrook can be reached at 877-486-9257 begin_of_the_skype_highlighting              877-486-9257      end_of_the_skype_highlighting begin_of_the_skype_highlighting              877-486-9257      end_of_the_skype_highlighting begin_of_the_skype_highlighting              877-486-9257      end_of_the_skype_highlighting begin_of_the_skype_highlighting              877-486-9257      end_of_the_skype_highlighting begin_of_the_skype_highlighting              877-486-9257      end_of_the_skype_highlighting.

1. Air Modeling for Non-Modelers:
What’s Up with the New Ambient Standards?
James A. Westbrook
October 12, 2010

2. Agenda: New Ambient Standards
• Compliance with ambient standards
• Ne ambient standards
New
• Strategies to pass the standards:
– Challenges you may face
– Quick refinement techniques to consider
– More advanced techniques
• Example for the 1-hour NO2 standard
p
• Conclusions

3. BlueScape, Inc.
• 20 years experience
• M
More than 100 modeling projects
th d li j t
• National Experience with AERMOD,
CALPUFF, th
CALPUFF other models d l
• Solve tough air quality modeling issues:
- A id modeling requirements
Avoid d li i t
- Develop meteorological data and monitoring data
- Refinement strategies for problem impacts
- Agency negotiations and protocols

4. What is Air Quality Modeling Used For?
• Compliance with criteria pollutant ambient
standards
– Permits, minor source NSR, PSD major source
– Environmental Impact Reports (EIRs)
• Human Health and Ecological Risk
Assessments
• Accidental chemical spills
• Long-range visibility impacts
• Toxic tort litigation
• AERMOD is the regulatory workhorse
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5. Typical Air Quality Modeling Study
• Need a Project
• Triggered by exceeding emissions significance
levels
• Modeling against significant impact levels (SILs), or
the full standard
• Hourly meteorological data and terrain data
• Full impact modeling to meet standards PSD:
standards,
- Project impacts +
- Other facility sources +
- Nearby facilities +
- Monitored background concentrations

6. Primary National
Ambient Air Quality Standards or NAAQS
NAAQS*
Averaging Value
Pollutant Period (g
(g/m3)**
)
PM10 24-hour 150
PM2.5 24-hour 35
NO2 1-hour
1 hour 188
NO2 Annual 100
SO2 1-hour 196
SO2 24-hour 367
CO 1-hour 10,000
CO 8-hour 40,000
,
* Partial List
** Equiv. units; state agencies may have different standards
See: www.arb.ca.gov/research/aaqs/aaqs2.pdf for standards

7. New Ambient Standards
• EPA has released three policy memos:*
– New NO2, 1-hour average, 100 ppb or 188 g/m3
– New SO2, 1-hour average, 75 ppb or 196 g/m3
– Justify PM10 as a surrogate for PM2.5 or model
PM2 5 24-hour average of 35 g/m3
PM2.5, 24 hour
• EPA’s unfinished business
– PSD SILs increments monitoring thresholds
SILs, increments,
– Background monitoring data availability
– Secondary PM2.5 formation, condensibles
www.epa.gov/region7/air/nsr/nsrmemos/appwno2.pdf
www.epa.gov/region7/air/nsr/nsrmemos/appwso2.pdf
http://bit.ly/9NeHnh
p y

8. New Air Modeling Challenges
• C b i sources
Combustion
- Relatively high NO2 emissions
- PM10=PM2.5
• Short engine or vehicle stacks, mean higher
impacts
• Low significance levels require full modeling
• P j t in next 1-2 years?
Project i t12 ?
- Due diligence modeling
- St t i design process
Strategic d i
- Stay close on EPA / state agency developments

9. “Quick Fix” Modeling Strategies to Pass
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• Project design changes
j g g
• Emission limitations
- Limit fuel or material throughput
- Limit hours of operation
- Limit hourly engine testing engine phasing
testing,
- Voluntary control technology installation
• Stack height increases
• Increase gas flow rate and temperature

10. Advanced Strategies to Pass
• PVMRM, OLM and ARM for NO2, as limited
by ozone
• Source Test for in-stack NO2/NOx ratios
• Modify the PM2.5 fraction in PM10, if relevant
• Review / adjust meteorological data
• Spatial / temporal modeling
- Show project does not cause or contribute to
significant impacts
- Consider only periods that contribute to high values
• Monitoring at Point of Maximum Impact
• Agency negotiation

11. Modeling Example
• Large gas-fired boiler and emergency
g
diesel engine
• Baseline, all NOx = NO2; high max. 1-
hour modeling + max background
max.
• Refinements:
a) H8H of daily maximum 1 hour values
1-hour
b) PVMRM with hourly ozone data, in-stack
NO2/NOx = 0.2
c) Source test for in-stack NO2/NOx ratio
d) Stack height increase, reduce emissions

12. 12

13. Baseline 1-hour NO2 Run
Impact = 1,132 + 88 = 1,220 g/m3 = FAIL!!
13

14. Modeling Refinements
Impact = 78 + 88 = 166 g/m3 = PASS!! 14

15. Model Run Summary
Baseline H8H Pull the Stops
Max. 1-Hour Avg.
g 1,132 g/m3
, g 636 g/m3
g 78.3 g/m3
g
NOx Concentration
w/background 1,220 g/m3 724 g/m3 166 g/m3
88 g/m3
g
Form of Result H1H H8H H8H
PVMRM Used? No No Yes
In-Stack NO2 Ratio -- 0.20 0.10
Engine Stack Height
g g 12 feet 12 feet 25 feet
% of Max Hour 100% 100% 50%
Engine Emission Rate
Advanced refinements were needed to pass ….
15

16. Conclusions
• New NO2, SO2 and PM2.5 ambient standards will
cause new challenges
• E
Expect (but confirm) that complicated f ll i
t (b t fi ) th t li t d full impact
t
modeling may be required
• Conduct modeling due diligence early to troubleshoot
problems
• Hire an expert modeling consultant
- Experience with the latest tools and guidance
- Experience passing the standards using advanced
techniques
- Interact with state agencies, come with a strategy
- Stay on top of developing EPA and state guidance

17. Next Webinar
EPA’s
EPA’ GHG R
Reporting P
ti Program i 2011
in 2011:
Are You Ready?
- What do I need to do to prepare?
- Key reporting timelines
- What are the roles and responsibilities?
- Comparison and overlaps with state requirements
- EPA software preview, reporting needs and data gap-filling
- Alternative calculation methodologies
Tuesday, December 7, 9 AM
https://www2.gotomeeting.com/register/836647746
p g g g

18. Contact with Questions
James A. Westbrook, President
BlueScape, Inc.
858-774-2009 (cell)
jwestbrook@bluescapeinc.com
www.bluescapeinc.com
p
The Webinar presentation will be p
p posted on
Slideshare and Scribd (search for BlueScape)