Technical reports can be kind of tricky and sometimes difficult to find. They are often referred to as grey literature.
Contributions in Marine Science (formerly the Publications of the Institute of Marine Science) - digital collection, v. 12-38, 1967-2009.
MSI Technical Reports
Mission-Aransas NERR Publications and Reports
NLM Technical Bulletin - U.S. National Library of Medicine | National Institutes of Health
NOAA National Marine Fisheries Service Scientific Publications Office
National Service Center for Environmental Publications, EPA
National Technical Reports - Beginning October 1, 2016, all subscribers (free registration) to the National Technical Reports Library (NTRL) will have open access, free of charge.
NOAA Technical Report NMFS
Sea Grant in the Gulf of Mexico, Oil Spill Science Publications & Fact Sheets
Technical Reports and Standards (Library of Congress) - Unit of the Library of Congress which holds over 5 million current and historical technical reports and standards on microform, digital media and paper.
TRAIL-Technical Report Archive and Image Library - TRAIL identifies, acquires, catalogs, and digitizes federal technical reports issued primarily prior to 1976.
WHOI Technical Reports, Memoranda, and Unnumbered Reports
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