National Status and Trends (NS&T) Mussel Watch Program provides status of and temporal trends of coastal contaminant conditions. Bivalve tissues are analyzed for a suite of about 600 legacy and emerging chemicals of concern. In addition, bivalve tissues are assessed for histopathology and gonadal index. The Program’s data, metadata and information products are managed within the guidance provided by NOAA’s Integrated Ocean Observing System (IOOS) and the National Monitoring Network, as recommended by the 2004 Ocean Action Plan. This document describes the Standard Operating Procedure (SOP) for mussel collections in Oregon State. Since 1986, Mussel Watch has established about 300 sites nationwide and 9 of these are in Oregon State (Table 1). Site descriptions can be found in Appendix 4. Detailed descriptions of the National Mussel Watch Program field manual are provided in Apeti, et al. (2012).