 A bivalve dredge is used in water deeper than 2 m, stainless steel tongs are used in 2-2.5 m deep water with a soft bottom, stainless steel pitch forks or quahog rakes are used in water less than 1 m deep, and collection by hand is done at some shoreline sites.The bivalves are then cleaned, packed in iced containers, and shipped to the appropriate analytical laboratory within two days of collection.NOAA awarded TDI-Brooks International with a five-year contract to analyze sediment and bivalve tissue chemistry from September 21, 2009 to September 20, 2014.