2013 Annual Report
1a.Objectives (from AD-416):
There are four main objectives for this study:
1) Develop PM2.5 emission factors and verify current PM10 emission factors for cotton gins across the Cotton Belt through stack sampling at gins in the West, Texas, MidSouth, and Southeast.
2) Collect field data to further quantify PM10 and PM2.5 EPA federal reference method stack and ambient sampler errors.
3) Develop point source and ambient total suspended particulate (TSP), PM10, and PM2.5 data sets that can be used in the design, development, and evaluation of current and future air quality models used for low-level agricultural sources.
4) Characterize the particulate matter emitted from cotton gins across the Cotton Belt in terms of particle size distribution, particle density, and particle shape.
1b.Approach (from AD-416):
The project plan is to evaluate six sites over the 2008 to 2010 ginning seasons, including a New Mexico gin, two California gins, a Texas gin, a Missouri gin, and a North Carolina gin. Selected gins should have similar abatement technologies (1D-3D cyclones with 2D-2D inlets on all exhausts) and process streams similar to the following: Module feeder or suction, No. 1 pre-cleaning, No. 2 pre-cleaning, overflow, No.1 lint cleaning, No. 2 lint cleaning, mote fan, mote trash fan, battery condenser, and master trash. Stack sampling will adhere to EPA protocols and will be performed by a certified stack sampling company under the supervision of the investigators. Stack sampling methods will include CTM-039, the EPA method for measuring PM2.5 stack emissions; Method 201, a standard EPA method for measuring PM10 stack emissions; and Method 5, a standard EPA method for measuring TSP stack emissions. Ambient air sampling will coincide with the stack sampling and will be conducted by USDA-ARS personnel and collaborators. The ambient sampling will follow USDA-ARS Air Quality Laboratory protocol. Samples of gin trash and other potential sources of ambient particulates (i.e., gin yard material) will be collected for analysis as particulate emissions parent material. Laboratory analyses, gravimetric and particle size analysis, and particle shape analysis will be conducted. All raw data will be compiled and organized for outside review. Results will be compiled in a report to the cotton ginners associations and project cooperators. The research will also be documented in the form of a series of manuscripts in peer reviewed technical journals to further disseminate the information for wider acceptance by the regulatory agencies and the scientific community.
Substantial results were achieved over the five-year term of the project through collaboration among ARS researchers at Mesilla Park, New Mexico; Stoneville, Mississippi; and Lubbock, Texas, and researchers at Oklahoma State University. Two advisory groups were established for the project to aid in project planning, gin selection, data analyses, and reporting: an industry group consisting of cotton ginning industry leaders and university and government researchers, and an air quality group that included members from state and federal regulatory agencies and university and government researchers. Seven cotton gins across the Cotton Belt in California, New Mexico, Texas, Missouri, and North Carolina were extensively sampled to obtain particulate emissions information. Every unique ginning system at each gin was source sampled using EPA-approved stack sampling methods to measure total particulate, particulate with diameter less than or equal to 10 microns (PM10), and particulate with diameter less than or equal to 2.5 microns (PM2.5) emissions. Concurrently, ambient particulate concentrations were sampled utilizing a 125-point ambient sampler array centered on the gins for approximately 10 days at each gin. Over the four years of field work for the project, more than 10,000 samples were collected and processed in the laboratory. From the field data collected, previously nonexistent PM2.5 emission factors for 17 different cotton gin systems were developed. Additional total particulate and PM10 emission factor data were developed for 11 cotton gin systems to improve the poor quality rating of current data. Also, total particulate and PM10 emission factors were developed for six previously undocumented gin systems. The emissions data, along with all background testing information and data, were transferred to project cooperators and advisory group members in the form of 51 technical reports published on the World Wide Web. Also, 52 peer-reviewed journal articles documenting the emissions data were submitted for review. The impact of this research was that the first PM2.5 emission factors for cotton gins were developed and total particulate and PM10 emissions data were bolstered. These data will aid state regulatory agencies in developing implementation plans to comply with EPA particulate regulations and, in turn, will aid the cotton ginning industry in that regulations will be based on sound scientific information specifically developed for that industry. Specific impact during the term of the project was that based on the data, a California regulatory agency recommended in its PM2.5 implementation plan no additional regulatory actions for cotton gins. Also, the regulatory agency in Texas revised its cotton gin permitting rules based on the data from this project. The overall impact of the accomplishments is that federal and state action agencies and the cotton ginning industry have both new and more complete information to more equitably regulate and to make better decisions concerning control of cotton gin particulate emissions. This will serve as a final report.