2007 Annual Report 1a.Objectives (from AD-416) Solid organic material recovered from the sewage treatment process, also known as sewage sludge or biosolids, are being applied to approximately 52,000 acres of agricultural land east of Denver, Colorado. This land has historically experienced wind erosion. Since biosolids are high in organic matter, they can potentially alter the soil structure and thus the wind erodibility of soils. The effect that the biosolids have on the wind erodibility of the soils is unknown. The USDA Agricultural Research Service (ARS) and the land manager have an interest in determining the effect of biosolids on the wind erodibility of the soils to which they are applied and the potential amounts that can be eroded from amended surfaces. 1b.Approach (from AD-416) The proposed research and expected results will contribute to the mission, strategies, and goals of the Wind Erosion Research Unit and the Particulate Emissions Component of the National Air Quality Programs (NP 203). The research seeks to elucidate the physical mechanisms by which particulates are generated, how they are transported and suspended in the air and their patterns of movement and deposition. The research goal is to support development of technology to reduce or prevent agricultural particulate emissions on biosoild amended land. Select field sites on the METROGRO Farm in Arapahoe and Elbert Counties, Colorado based on varying number of applications of biosolids to give a high, medium, and low level of biololids applications. Control sites will also be selected to which no biosolids have been added. Surface soil texture will be a similar as possible for all sites. 3.Progress Report This report documents research conducted under a Non-Funded Cooperative Agreement between ARS and Denver Metro Wastewater Reclamation District. Additional details of research can be found in the report for the in-couse associated project CRIS 5430-11120-007-00D, Particulate Emissions From Wind Erosion: Processes, Assessment, and Control. Field sampling was conducted on December 13-14, 2006, April 4-5, 2007 and July 5-6, 2007. Field wind erosion catchers at two sites were installed on December 13, 2006. Wind erosion catch samples were collected on several dates by Denver Metro personnel and by ARS person on April 4, 2007. The erosion catchers were removed from the field on June 13, 2007. A progress report of the research was presented at the 2007 Residuals and Biosolids Management Conference on April 17, 2007 in Denver Colorado. Methods of monitoring this project included, discussing project plans, reviewing program goals and accomplishments with the Cooperator’s PI at ARS facilities; stakeholders meetings; by teleconference, e-mail and other types of written correspondence; providing technical advice to Cooperator’s personnel; and conducting site visits at Cooperator’s facilities.