1. Texas Commission on Environmental Quality (TCEQ) Differential Absorbtion Lidar (DIAL) Project Summer 2007 Texas City, Texas

2. Project Objective Compare DIAL measurements with emissions calculated using traditional emission factors and calculation techniques Measure emission sources located at a bulk storage facility and a refinery in the Houston, Galveston and Brazoria, Texas area

3. Project Status Draft DIAL report currently under review by TCEQ - Dec 2007 After TCEQ review, the report will be sent to project participants for review and comment and then forwarded to EPA - January 2008 TCEQ’s final report - June 2008

4. Project Funding Total project cost $650,000  $200,000 funded by new technology EPA grant  $450,000 funded by TCEQ

5. Project Technology DIAL- Service provided by National Physical Laboratory (NPL) Hawk Camera - Service provided by Leak Surveys Inc. UV-DOAS (Ultraviolet-Differential Optical Absorption Spectroscopy) - Provided by EPA Ambient Sampling- Performed by TCEQ staff and NPL

6. Bulk Storage Facility Measurements July 16 th to July 20 th 3.5 days of DIAL measurements on naptha tanks with Hawk Camera footage One night of DIAL measurements on large naptha tank

7. Bulk Storage Facility Measurements cont. One large external floater  Tank recently tested and well maintained  Additional wiper seal  Leg supports had fabric covers Two internal floating roof tanks with hanging roofs

9. Refinery July 25 th to August 18 th Operated at less than 50% capacity – hurricane damage and turn around projects Heavily industrialized area around the refinery

10. Refinery Sources Fixed roof diesel tanks External floating roof crude tanks External floating roof gasoline tanks Wastewater treatment area including a separator Heated storage tanks Three nights of storage tank measurements

11. Refinery Sources cont. Coker unit  Total VOC  Benzene- during decoking process Aromatic Recovery Unit Sulfur recovery unit Temporary flare Large process flare

13. Coker Unit Coker Design  4 product cuts with overhead vapor sent to a vapor recovery unit or into the refinery fuel gas system DIAL benzene measurements  Measured during decoking process

14. DIAL Technology Validation Techniques UV-DOAS measurements closely agreed with DIAL measurements Canister and tube samples agreed closely with DIAL measurements

15. DIAL Technology Validation Techniques cont. Inline gas calibration cells provided by the refinery Dial measurements very close to actual concentrations for propane, pentane and benzene Benzene  Actual 1000 ppm  Predicted 900 ± 70 ppm

16. Questions? Contact:  Russ Nettles, Team Leader Emissions Assessment Section, Air Quality Division of the TCEQ’s Chief Engineer’s Office  512 239-1493  rnettles@tceq.state.tx.us