1. Anchorage CO Limited Maintenance Plan
A plan addressing the second 10 years of the CO maintenance planning period
Department of Health and Human Services
Municipality of Anchorage
October 2012
Anchorage CO Plan Update

2. Section 175A of the Clean Air Act requires the submission of a maintenance plan revision midway through the twenty year maintenance planning period.
Anchorage’s twenty year CO Maintenance planning period runs from July 23, 2004 through July 22, 2024.
The Anchorage revision must address second ten years (July 2014 – July 2024)
The draft Anchorage CO Maintenance Plan revision was prepared using the limited maintenance plan (LMP) option.
Anchorage CO Plan Update

3. What the heck is a “limited maintenance plan”?
Anchorage CO Plan Update

4. EPA offers LMP option to areas where the design value is 85% or less of the CO standard.
CO NAAQS = 9 ppm (as 8-hr average)
85% of CO NAAQS = 7.65 ppm
Anchorage DV (2011) = 6.0 ppm
Preparation of the CO maintenance plan revision under the LMP option is simpler and less rigorous than a full maintenance plan revision.
Once EPA approves an LMP, regional air quality conformity procedures are greatly simplified.
Anchorage CO Plan Update

5. The Anchorage CO LMP was prepared in accordance with EPA guidance contained in the “Paise memo” drafted in 1995.
This guidance discusses how the five core provisions of an LMP should be addressed:
attainment inventory
maintenance demonstration
monitoring to verify continued attainment of the CO NAAQS
a contingency plan
conformity determination requirements under an LMP.
Anchorage CO Plan Update

6. Attainment inventory Sources of CO Emissions in Anchorage Bowl (2007)
Source Category
CO Emitted (tons per day)
% of total
Motor vehicle – running emissions
40.5
25.4%
Motor vehicle – start emissions
84.8
53.4%
Motor vehicle – extended idling by combination long-haul trucks
0.3
0.1%
Subtotal – Motor Vehicles
125.6
78.9%
Ted Stevens Anchorage International Airport Operations
12.4
7.8%
Merrill Field Airport Operations
0.7
0.4%
Wood burning – fireplaces and wood stoves
6.2
3.9%
Space heating – natural gas
3.8
2.4%
Miscellaneous (railroad, marine, snowmobiles, snow removal, portable electrical generators, welding, etc.)
9.3
5.8%
Point sources (power generation, sewage sludge incineration)
1.3
0.8%
Subtotal – Other Sources
33.7
21.1%
TOTAL – ALL SOURCES
159.3
100%
Anchorage CO Plan Update

7. Highest 2nd Max 8-hr Concentration Measured
Maintenance Demonstration
The update must show that the DV in Anchorage qualifies for the LMP option
Highest 2nd Max 8-hr Concentration Measured
in Preceding Two-Years (all values in ppm)
Garden
Seward
Hwy
Turnagain
DHHS
DVPaise
2002
5.7
5.2
7.7
2003
5.4
6.7
2004
6.4
5.5
7.9
2005
2006
4.8
6.1
2007
4.3
2008
3.8
3.1
2009
4.4
5.8
3.6
2010
6.0
2011
2.8
DV has been ≤ 7.65 ppm since 2006.
Anchorage CO Plan Update

8. Air quality public awareness program
The update continues the commitment to implement the primary control measures currently included in the maintenance plan:
Air quality public awareness program
Transit marketing
Carpooling and Vanpooling
Anchorage CO Plan Update

9. Monitoring to verify continued attainment of the CO NAAQS
The update commits Anchorage and/or State of Alaska to continued monitoring to verify compliance with the CO standard
The current CO network includes four sites. The highest concentrations are measured at the Turnagain site in residential Spenard.
Anchorage CO Plan Update

10. Contingency plan
The previous plan included a commitment to implement at least one of six contingency measures if a future violation of the CO standard occurs. The update affirms this commitment.
Menu of Contingency Measures
Increasing public awareness, transit marketing and carpool/vanpool efforts
Curtailing or limiting the use of fireplaces and woodstoves when high CO is predicted
Offering reduced fares or free transit for employees of companies that contribute to transit subsidies
Reinstating the engine block heater installation subsidy
Reinstating the ethanol blended gasoline requirement
Reinstating the I/M Program
Anchorage CO Plan Update

11. Conformity determinations under an LMP
A motor vehicle emission budget is not required in an LMP.
EPA guidance states that “emissions budgets in limited maintenance plan areas may be treated as essentially not constraining.”
The EPA has concluded that for transportation purposes, the emissions in a qualifying LMP area need not be capped for the maintenance period and thus no emissions budget is required in the maintenance plan.
Anchorage CO Plan Update

12. Tentative Approval Schedule
AMATS TAC release of draft CO LMP for 30-day public review
Sept 13, 2012
AMATS AQ Committee review and recommendation
Oct 2, 2012
AMATS TAC recommendation on CO LMP
Oct 11, 2012
AMATS Policy Committee review/approval of CO LMP
Oct 25, 2012
Anchorage Assembly considers CO LMP for adoption
Nov 13, 2012
ADEC public review process
Dec 2012 – Jan 2013
ADEC legal review, adoption of CO LMP as a revision to the SIP
Feb 2013 – May 2013
ADEC submits SIP revision to EPA for approval
Jun 2013
EPA adequacy review of new conformity procedure (up to 90 days)
Jun 2013 – Aug 2013
Anchorage CO Plan Update