Andrew Winkelman NOAA/GLERL 2205 Commonwealth Blvd. Ann Arbor, MI 48105-2945 Phone: (734) 741-2336 Fax: (734) 741-2055 e-mail: andy.winkelman@noaa.gov Sediment traps capture settling particles in the water column. Trap materials provide information about sedimentation and resuspension rates in different areas. Over 1,200 sediment trap samples were collected as a part of the EEGLE program using automated sequential samplers (23 samples per deployment) and passive sediment traps (1 sample per deployment). Samplers were deployed on steel cable mooring lines at various stations around Lake Michigan, typically at 30m below the surface (in the epilimnion) and 5m above the bottom (in the nephloid layer). Upon retrieval, sediment trap samples were screened at 355um to remove larger biota and debris. Some samples were further screened at 65um or split in half. The >355um screened material was back-washed onto filters, dried, weighed, and archived. The smaller size fractions (<65um or >65um - <355um) were freeze-dried, weighed, ground, and archived. TC, TN, TOC, TON, IOC, TP, P-NaOH as P, SiO2-bio, del C-13, del N-15, and Cs-137 values were determined for the smaller size fractions as sample size allowed. Two versions of the sediment trap master file have been submitted to the EEGLE web page. The first version lists trap locations, dates, and mass flux measurements. The second version includes the same information as the first version with the addition of chemical constituent data as described above. Because constituent analysis is on going, the second version will be updated periodically. The first line of both data files will indicate the most recent update. The information in the data files (in addition to mass flux and chemical parameters) includes the station name and location (latitude and longitude), the station and sampling depth, the sampling period start and end dates, the EEGLE operations number, and any relevant notes or comments. trap_massflux.xls (EXCEL file, 390K) trap_constituents.xls (EXCEL file, 446K)