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

     Stand-alone transmissometers were deployed in the Benton Harbor Hot Spot 
area to measure suspended matter levels over extended periods of time (several months).  
The instruments were attached to steel-cable mooring lines at various depths and 
locations.  The mooring lines consisted of 10cm or 25cm pathlength transmissometers, 
data logging devices, and occasionally a water sampling device (1999 was the only 
successful deployment of a water sampler).  Deployment occurred before the spring 
resuspension event and retrieval occurred after the event.  The instruments sampled every 
ten minutes in 1999 and every 20 minutes in 2000.  For the year 2000 deployment, 
instruments were pulled midway through the deployment to change the batteries and 
clean transmissometer lenses.  Upon retrieval, the data was downloaded from the data 
logging devices in the form of scan number and transmissometer voltage.  It was then 
converted to time in the form of Julian Day (day 1 = 12/31/1899) and beam attenuation 
coefficient.  Header files were added that include station name, sampling depth and 
location, start and end dates, and instrument information.