Airport Pb. EPA-OTAQ Presentation for the NACAA Monitoring Subcommittee 9 Feb 2010

Transcription

1 Airport Pb EPA-OTAQ Presentation for the NACAA Monitoring Subcommittee 9 Feb

2 Topics Airport Pb studies informing the issue of monitoring in the context of the Pb NAAQS Pb measurements at/near airports Modeled airport Pb Where are airport Pb monitors being sited? Why is there ambient air on airport property and why is it relevant for Pb monitoring? Airports with Pb inventories greater than or equal to 0.50 tons using 2008 data Draft memo and information we are requesting from States 2

3 Leaded Avgas Overview Lead from avgas is 50% of the national inventory >700 tons Pb in 2008 There are ~20,000 airports in the U.S. ~3,000 classified as important for national transportation by FAA Airports supply aircraft operations counts for these airports to FAA EPA uses this information to calculate Pb inventories 3

4 Dense Network of Airports & Heliports 4

5 Leaded Avgas is Used Only in Piston-engine Aircraft Air taxi, personal transportation, instructional, business/corporate, other (e.g., aerial application, observation) Activity by these aircraft is categorized as General Aviation (GA) and Air Taxi (AT) Lead needed to prevent knock 2 grams Pb/gallon (tetraethyl lead) Over 600,000 pilots Over 145 million passengers 5

6 Airport Pb Studies Santa Monica Santa Monica modeling Van Nuys Buttonville (near Toronto) 6 months 1 year 6 months 10 days 6

7 Santa Monica SCAQMD study 7

8 Santa Monica Modeling Evaluation 14,050 LTO 8

9 Van Nuys SCAQMD Pb Study 9

10 Relationship between LTOs and Ambient Pb Buttonville Airport 100 LTO/day = μg/m 3 24-hr R 2 = 0.7 Inventory approach 0.50 tons = 64,800 LTO (178/day) The monitoring emission threshold is intended to identify Pb sources which may have the potential to contribute to or approach an exceedance of the Pb NAAQS and near which Pb monitoring should be conducted (or where a site-specific evaluation of the potential for the Pb source to contribute to an exceedence of the Pb NAAQS should be performed). 10

11 Potentially Impacted Population About 2 million people live within 1 km of the 20,000 airports Land near GA airports is sought for residential development About 3 million children attend schools that are located within 1 km of these airports Includes more than 8,000 schools 11

12 Where are Airport Pb Monitors Sited? Airport monitors, as with other source-oriented monitors, are sited in the max impact location accessible to the general public. For airports this is downwind from the run-up / takeoff area Why is this the relevant location? It complies with the monitoring guidelines and includes consideration of population exposure Some people live on airports 45 meters from the center of the runway (up to 600 airports) Neighborhoods, schools and recreational fields within 50 meters of the max impact areas Children, young adults, renters, pilots and other members of the public move freely through these areas 12

13 Fly-in Communities 13

14 Ambient Air at Airports 14

15 NAAQS-related Airport Pb Monitoring Four airports with 1.0 ton or more 68 airports with 0.50 tons or more These airports differ from the 1 ton airports in important ways Almost exclusively piston-engine activity Single runway Smaller footprint (residential areas closer to max impact area) One run-up area Shorter runway Strong seasonal activity Pilot training 15

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20 Airport Pb Inventories Pb =(piston-engine LTO)(7.34 g Pb/LTO)(0.95) Key Data Inputs Landing and Take-off (LTO) information To evaluate piston versus jet activity we are using the basedaircraft split. Airport operators and/or states have told us this is a realistic reflection of piston-engine activity (Tetterboro, Reid-Hillview, Camarillo, Santa Monica) Emission factor Fuel consumption data from 8 aircraft engine/frames in FAA s inventory model Time-in-mode data, excluding run-up checks Pb concentration in fuel, 2.12 grams / gallon We estimate 5% of the lead in fuel is retained in the engine/oil 20

21 State Inquiries with Airports Could Improve Pb Inventories 1) LTOs conducted by single and multi-engine aircraft (i.e., piston-engine aircraft) 2) The time spent in each mode of the LTO cycle including run-up time which is currently not in airport-specific inventories 3) Concentration of lead in the aviation gasoline supplied at the airport 4) Fuel consumption rates by the piston-engine aircraft operating at your airport of concern 5) Amount of lead retained in the engine and oil 21

22 Revising Airport Pb Inventories I have CDs with airport data we use to calculate Pb inventories 19 states have Pb inventories 0.50 tons Please see me if you would like the data for your state Send me your airport-specific data & submit it to the NEI (draft 2008 currently undergoing state review) We will finalize the memo for the Pb NAAQS docket There will be additional opportunities to revisit airport inventories for purposes of the Pb monitoring rule implementation 22

23 Questions? Technical Support Document Describes inventory method Lists information States could obtain to improve airport inventories Petition on avgas Pb and EPA actions My contact information