Landmarks and reference points play an important role in the designation of permitted disposal sites. Primary reference points include the Marblehead Light, the former Boston Lightship, and the Dumping Grounds (or "DG" buoy) and the Industrial Waste Site "A" buoy. Secondary landmarks include the Boston Light and Minots Ledge Light. Typically, permits cited vectors or radii against such landmarks, buoys and lights. The EPA (Tordoff, 1991a-d) provided a compilation of the relevant chemical and radioactive waste disposal site reference points that were in part derived from U.S. Congressional Hearings in Boston in 1981 (USHR, 1981). The EPA also reviewed more recent historical dredged material disposal site activities in the bay (EPA, 1989b). These references were used to provide appropriate coverages in the GIS. Several 2 nautical mile diameter circles lie along the western edge of the Stellwagen Bank National Marine Sanctuary.  The northwestern circle represents the "Foul Area" or Industrial Waste Site (IWS).  The western and eastern circles represents the present and former dredged material disposal sites, or Massachusetts Bay Disposal Site (MBDS), respectively. The Boston Lightship Dumping Grounds served as one of several repositories for dredged materials and other wastes. Many sea floor features associated with the disposal of dredged materials are visible in the shaded relief and psuedocolored backscatter images provided in Library 3. The analog and digital laser line scan system images and underwater video clips taken in the waste site areas illustrate some of the sea floor conditions and biota that inhabit these areas.

For the Clelia dives, there are four files associated with each dive.   For example, for Dive 475, there are shapefiles 475cle.shp (containing locations of submersible during dive), 475lls.shp (contains location of each laser line scan snapshot), 475vln.shp (containing the track line of the vessel supporting the Clelia dive), and 475wpt.shp (containing comments logged at a specific location during dive).  For simplicity of this view, the shapefiles vln and wpt are not included in the view (although they are listed in the metadata tables as associated with this view.  The files may be found in the 2_waste/bls Directory (for Clelia dives 475-481) and in Directory 2_waste Directory on the CD-ROM.

Coverages provided in Library 2:    (Summary metadata for files in the Library 2 view are listed alphabetically in the table below. For complete metadata, go to directory "9_biblio" on this CD-ROM and open the file metadata.mdb using Microsoft Access or the file Gismeta.htm using your browser.)