Technical Support Document : Printed on Recycled Paper Analysis of California's Request for Waiver of the Reformulated Gasoline Oxygen Content Requirement for California Covered Areas

By Environmental Protection Agency

Book Id: WPLBN0000000502
Format Type: PDF eBook:
File Size: 0.3 MB
Reproduction Date: 2007

Title:	Technical Support Document : Printed on Recycled Paper Analysis of California's Request for Waiver of the Reformulated Gasoline Oxygen Content Requirement for California Covered Areas
Author:	Environmental Protection Agency
Volume:
Language:	English
Subject:	Ecology, Natural resource issues, Environemtal protection
Collections:	Environmental Awareness Library Collection
Historic Publication Date:
Publisher:	United States Environmental Protection Agency


Citation APA MLA Chicago Protection Agency, B. E. (n.d.). Technical Support Document : Printed on Recycled Paper Analysis of California's Request for Waiver of the Reformulated Gasoline Oxygen Content Requirement for California Covered Areas. Retrieved from http://gutenberg.us/

Description
Excerpt: CARB provided a more detailed analysis in a submittal to EPA dated July 9, 1999. (Filed in docket A-2000-10, document number II.D.-2; also available at http://www.arb.ca.gov/cbg/Oxy/wav/070999.pdf ) . CARB attempted to demonstrate that an additional 1.5 percent reduction in NOx reductions could be achieved with zero oxygen in California’s gasoline. CARB also claimed that it would be impossible to achieve the same level of additional NOx reduction with the 2.0 weight percent oxygen requirement in place. CARB argued that additional NOx reductions are needed in order for California to attain ozone and PM NAAQS. CARB concluded that in light of these findings, the federal oxygen content requirement interferes with attainment of both the ozone and PM NAAQS. CARB based its argument on the use of its Phase 2 Predictive Model1. The reductions in NOx under both the 2.0 weight percent oxygen and non-oxygen scenarios were based on reduction of sulfur in the fuel and the relationship between NOx formation and oxygen level in the fuel. No other parameters were discussed in this submittal.

Table of Contents
TABLE OF CONTENTS I. CHRONOLOGY OF EVENTS AND GENERAL DESCRIPTION OF CALIFORNIA’S SUBMITTALS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 A. Governor Davis’ April 12, 1999 petition for waiver . . . . . . . . . . . . . . . . . . . . . . . . . . 1 B. California Air Resources Board (CARB) July 9, 1999 submittal . . . . . . . . . . . . . . . . 2 C. CARB September 20, 1999 response to EPA questions . . . . . . . . . . . . . . . . . . . . . . . 3 D. CARB December 24, 1999 submittal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 E. CARB February 7, 2000 submittal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 II. SUMMARY OF CALIFORNIA’S WAIVER REQUEST . . . . . . . . . . . . . . . . . . . . . . 8 III. EPA’S EVALUATION OF CALIFORNIA’S PETITION . . . . . . . . . . . . . . . . . . . . 16 A. Evaluation of the oxygen content-NOx emission relationship . . . . . . . . . . . . . . . . . 18 1. CARB’s Phase 3 Predictive Model (PM3) . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 2. Description and comparison of available models for predicting NOx emissions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 3. Audit and verification of PM3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 a. Handling of Vehicle Technology Groupings . . . . . . . . . . . . . . . . . . . . . . . 24 b. The Dataset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 c. Statistical approach . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 d. Statistical treatment of High-Emitters . . . . . . . . . . . . . . . . . . . . . . . . . . 28 e. Choice of final model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 4. Effect of Oxygen on NOx Emissions from Tech 5 Vehicles . . . . . . . . . . . . . 29 a. Studies of the Impact of Fuel Quality on Tech 5 Vehicle Emissions . . . . 31 b. The Auto Oil Study . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32 c. The CRC Study . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 d. The Toyota Study . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37 e. Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39 5. EPA Model Building For Tech 4 Vehicles . . . . . . . . . . . . . . . . . . . . . . . . . . . 40 a. Tech 4 modeling decisions and assumptions . . . . . . . . . . . . . . . . . . . . . . . 41 b. Statistical methods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45 c. Variability in model predictions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50