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PROPOSAL:

Execute Contract to Evaluate Diesel Particulate Sampling Methodology and Determine Zone of Influence of Ultrafine Particle Fraction of On-Road Emissions

SYNOPSIS:

Diesel sampling and measurement procedures for particle number and size from mobile sources are not standardized, and the applied laboratory procedures do not reflect the actual on-road conditions. The Coordinating Research Council (CRC) has issued an RFP to evaluate and refine the sampling and measurement procedures and compare them to actual on-road conditions. Total project cost is approximately $1,200,000. AQMD's contribution shall not exceed $100,000, with the balance being co-funded by the CRC, the Engine Manufacturers Association, and the National Renewable Energy Laboratory.

COMMITTEE:

Technology, March 27, 1998, fewer than three members were present and therefore, pursuant to the Procedures for Standing Committees of the Governing Board, the Committee forwards this letter without recommendation.

RECOMMENDED ACTION:

Authorize the Chairman to execute a contract with CRC in an amount not to exceed $100,000, to co-fund a project to evaluate diesel particulate sampling methodology and determine the zone of influence of the ultrafine particle fraction of on-road emissions.

Barry R. Wallerstein, D.Env.
Acting Executive Officer

Background

Particulate matter is most often characterized in terms of its mass within a given particle size range. For example, the new PM2.5 National Ambient Air Quality Standard (NAAQS) is an annual or a daily average of, respectively, 15 or 65 grams per cubic meter. The new PM2.5 NAAQS and concerns over ultrafine particles have renewed interest in determining particle number counts, and characterizing particle size distributions, bulk chemical composition, and surface properties of primary PM emissions from mobile sources. In addition, there is an increased interest due to the fact that modern high pressure, injection diesel engines may have lower PM mass emission rates than earlier technology engines, but higher emissions of very small particles. Unfortunately, the sampling and measurement procedures for particle number and particle size from mobile sources are not standardized, and are subject to considerable uncertainty.

Currently, a dilution tunnel is utilized to measure PM mass emission rates from mobile sources. Filtered dilution air is drawn into the tunnel for mixing with the exhaust. A constant flow rate of diluted exhaust is maintained in the tunnel, giving a dilution ratio of 2:1 to 10:1 depending on the engine and the load. This situation is clearly different from what happens on the road, where turbulent mixing results in a rapid, high dilution ratio process. During this dilution process, condensation and evaporation processes affect the number, size, and composition of the particles. Therefore, it is necessary to find out what methodology is most appropriate for determining the impact of mobile source emissions on ambient particulate air quality.

Proposal

The Coordinating Research Council (CRC) is a non-profit organization that directs, through committee action, engineering and environmental studies on the interaction between automotive equipment and petroleum products. The Sustaining Members of CRC are the American Petroleum Institute, the Society of Automotive Engineers and the United States Council for Automotive Research.

CRC has issued an RFP to conduct a study which in its entirety is expected to involve the following aspects: determining the actual particle size distribution and particle number concentration in the exhaust plume from heavy-duty diesel vehicles operated on the road; comparing that information with data generated in emission test facilities to determine if current sampling and analysis methods are adequate for characterizing particle size and number; examining particle transformations as the plume disperses downwind of the roadway in a typical urban situation, with the objective of determining the zone of influence of the ultrafine particle fraction of the emissions from a roadway; and characterizing the bulk PM chemical composition and determining surface properties and composition.

By the proposal submission due date of February 2, 1998, CRC had received a total of six proposals from the following entities:

1. West Virginia University

2. University of Minnesota

3. Southwest Research Institute

4. University of Georgia

5. CE-CERT

6. California Truck Testing Services

All the proposals were reviewed by staff from the CRC, the National Renewable Energy Laboratory (NREL), the Engine Manufacturers Association (EMA), and the AQMD. The proposals submitted by West Virginia University, University of Minnesota, and Southwest Research Institute received rankings which advanced them to the second evaluation stage, with final selection scheduled for the end of April.

The proposed project is included in the Technology Advancement Plan, approved by the Board on September 12, 1997, as part of Project 97T3-1, "Advanced Transportation Systems Research, Development and Demonstration." Due to the timing of the project, funding for this study will be allocated from the FY 1998-99 Budget. The major benefit of this project include evaluation and improvement of sampling and measurement methodologies of ultrafine particles from exhaust emissions, which can in turn help better understand their health effects and further enhance the commercialization of clean fuel vehicles.

Sole Source Justification

Section VIII, (B)(2) of the Procurement Policy and Procedure identifies four major provisions under which a sole-source award may be justified. This request for a sole source award is made under provision B.2.d.: Other circumstances exist which in the determination of the Executive Office require such waiver in the best interests of the AQMD. Specifically, these circumstances are: B.2.d.(1) project involving cost sharing by multiple sponsors.

As an auto/oil research consortium, CRC is the pre-eminent leader in the United States in the area of conducting mobile source emission studies. It was a major player in the development and implementation of the Southern California Air Quality Study (SCAQS). During the past eight years, it has conducted an on-road vehicle emissions workshop in San Diego and presented numerous papers in this field. It was the leading group conducting the tunnel studies of 1987, 1995, and 1996, which were co-sponsored by the AQMD.

Both the NREL and the EMA are cosponsoring this study and their knowledge and expertise are valuable assets toward the successful completion of this project in terms of providing inputs and peer review. In addition, the participation of NREL and EMA with CRC in this project provides significant cost sharing which leverages AQMD's contribution to a ratio of 1:11.

Resource Impacts

Total cost for the proposed contract is approximately $1,200,000. AQMD's co-funding shall not exceed $100,000, with the remaining balance being co-funded by CRC for $400,000, NREL for $550,000, and EMA for $150,000. Sufficient funds will be available in the FY 1998-99 Budget, pending Board's approval of the Budget, from revenues received from the state-mandated Clean Fuels Program. The Clean Fuels Program, under Health and Safety Code Sections 40448.5 and 40512 and Vehicle Code Section 9250.11, establishes mechanisms to collect revenues from mobile and stationary sources to support projects to increase the utilization of clean fuels in both sectors, including the development of the necessary advanced enabling technologies. Funds collected from motor vehicles are restricted, by statue, to be used for projects and program activities related to mobile sources that support the objectives of the Clean Fuels Program.

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