EPA 520/1-83-018
          GEOLOGIC OBSERVATIONS  AT THE 2800-METER
            RADIOACTIVE  WASTE  DISPOSAL SITE  AND
        ASSOCIATED DEEPWATER DUMPSITE  106  (DWD-106)
                   IN  THE  ATLANTIC OCEAN
                           by

      Martine Dreyfus Rawson and William B.F. Ryan

            Department of Geological Sciences
          Lamont-Doherty Geological Observatory
                 of Columbia University
               Palisades, New York  10964
                   Prepared June 1978
                 Revised September 1983
This report was prepared as an account of work sponsored
       by the U.S.  Environmental Protection Agency
              under Contract No. 68-01-3933
                     Project Officer

                     Robert S.  Dyer
              Office of Radiation Programs
          U.S.  Environmental  Protection  Agency
                 Washington,  D.C.   20460

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                                  FOREWORD

      In response to the  mandate  of  Public  Law 92-532,  the Marine
 Protection,  Research,  and  Sanctuaries  Act  of  1972,  as  amended,  the
 Environmental  Protection Agency  (EPA)  has  developed a  program to
 promulgate regulations and criteria to control the  ocean disposal of
 radioactive  wastes.  As  part of  that program,  the EPA  Office of Radiation
 Programs  initiated  feasibility studies in  1974 to learn whether present
 technologies could  be  used to determine the fate of  radioactive wastes
 dumped  in the  past.
      In 1975 and  1976, the advanced  technologies represented by the
 manned deep-submergence  research vehicle (DSRV) ALVIN  were employed to
 perform an on-bottom survey at the Atlantic Ocean deepwater industrial
 waste dumpsite  (DWD-106)  and the previously-used United States low-level
 radioactive waste disposal site.  DWD-106 is located approximately 170
 kilometers (106 miles)  offshore at a depth ranging between 1600-2500
meters.  The low-level radioactive waste disposal site is located
 southwest of DWD-106 approximately 190km (120 miles) offshore at a depth
of approximately 2800 meters (9300 feet).   Both sites are situated south
of the axis of the Hudson Canyon channel.   The objectives of this survey
were to describe the biological,  chemical,  geological and physical
oceanographic characteristics of the dumpsites, with the submersible
being used primarily to make direct observations of  the geological and
biological conditions at  the two dumpsites.
                                iii

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     The present report provides a detailed description of the geological]!

and topographical characteristics of the two dumpsite areas.  Three

submersible dives were made in the 2800m low-level radioactive waste

dumpsite and five dives were made at DWD-106.  The sediment deposits,

bottom topography, evidence of sediment avalanching, biota, currents,  and|

the differences in these parameters between the two dumpsite areas are

discussed.  The presence of radioactive waste drums in the 2800m dumpsite|

area is analyzed in terms of the localized geological and physical

processes occurring at the site.  The report concludes with a general

discussion of the geologic stability of the two dumpsite areas which

straddle the lower continental slope - upper continental rise provinces.

     The Agency invites all readers of this report to send any comments

or suggestions to Mr. David E. Janes, Director, Analysis and Support

Division, Office of Radiation Programs (ANR-461),  Environmental

Protection Agency, Washington, D.C.  20460.
                                      Glen L.  Sjoblom,  Director
                                     Office of Radiation Programs

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                                TABLE OF  CONTENTS
                                                                           Page
 INTRODUCTION [[[      !
 SUMMARY [[[      2
 REGIONAL GEOLOGIC SETTING ..............................................      4
     Continental Slope .................................................      7
     Continental Rise ..................................................    15
     Nature and Composition of the Sediment Cover ......................    20
 THE 1975 SUBMERSIBLE DIVING PROGRAM ....................................    25
 THE 1976 SUBMERSIBLE DIVING PROGRAM ....................................    32
 CONCLUSIONS AND RECOMMENDATIONS ........................................    45
 UNRESOLVED PROBLEMS [[[    47
 REFERENCES [[[    50

                                 LIST OF TABLES
 1.   Location, Depths, and Environment of DSRV ALVIN Dives
       of the 1975 EPA Radioactive Waste Disposal Site Survey ..........    28
 2.   Locations, Depths,  Observers, Environment, and Objectives
       of DSRV ALVIN Dives of the 1976 EPA Radioactive Waste
       Disposal Site Survey ............................................    35

                                 LIST OF FIGURES
 1.   Deep-sea core locations and bathymetric contours of the
       east coast conti nental  margi n ...................................     5
2.   Dendritic-type drainage pattern in Heezen Canyon on the
       continental  slope of New England ................................     6

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                           LIST OF FIGURES (Continued)
                                                                          Page
5.    Holes and mounds of biological origin on the upper continental
       rise in the northeastern section of Deepwater Dumpsite 106
       (DWD-106)	     12

6.    Position of ancient shore lines on the continental shelf
       east of New Jersey and Delaware	     14

7.    Bathymetric profiles across the continental margin
       of the east coast of the United States	     16

8.    Water mass, sediment, and bottom current structure across
       the east coast conti nental margi n	     17

9.    Distribution of bottom photograph stations showing evidence
       of bottom current directions and relative magnitudes		     18

10.  Umbel Tula deflected in westerly current within a narrow
       meandering channel on the upper continental rise	     21

11.  Lithologies of selected cores from the upper and lower
       continental rise seaward of New Jersey and Delaware	     23

12.  Calcium carbonate contents in surface sediment samples
       from the western North Atlantic	     26

13.  Location of 1975 DSRV ALVIN dives	     29

14.  Barrel #28 photographed on ALVIN Dive 676 at a depth of
       2819 meters	     34

15.  Bathymetric contours and dive tracks from the 1976 survey on
       the southeastern corner of  the 2800m low-level  radioactive
       waste dumpsite	     36

16.  Encrusting sponges, hydrozoans, and anemones on outcrops  of
       lithified marlstone	     38

17.  Partly obliterated sled marks from a 1975 ALVIN dive in the
       2800m low-level radioactive waste dumpsite	    39

18.  Ski  marks  on the seabed made  by DSRV ALVIN	    41

19.  Large, sub-rounded olistolith lying partly  buried within  a
       slump scar at  the southeast corner of the 2800m low-level
       radioactive waste dumpsite	    42

20.  Example of an erosional moat  around a corroded and
       partly buried  drum  of radioactive waste	    44
                                 vi

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                                  INTRODUCTION

     The deepwater radioactive waste dumpsite addressed in this report is an
area of about 100 square nautical miles (342 square kilometers) in the Northwest
Atlantic which lies astride the boundary between the lower continental slope and
upper continental rise of the eastern margin of North America.  The dumpsite is
approximately 120 nautical miles east of Cape Henlopen, Delaware.   Water depths
at the dumpsite range from about 2500 meters to 2800 meters,.   Seafloor relief
is locally smooth, and the site is centered at 38°30'N, 72°06'W.

     The general area which is almost contiguous to this radioactive waste
dumpsite is referred to as Deepwater Dumpsite 106 (DWD-106),,   Baseline
investigations were initiated in 1974 by the National Oceanic and Atmospheric
Administration (NOAA) which is charged with the responsibility, under
Title II of Public Law 92-532, to investigate the environmental effects of
dumping of waste material into ocean water and onto the seabed.

     Geologic field studies of the low-level radioactive waste dumpsite were
undertaken by the U.S. Environmental Protection Agency in the summers of 1974,
1975, and 1976, and involved sampling and bathymetric soundings from surface
vessels, and direct seafloor observation, photography, video recording and
sampling by the manned submersible DSRV ALVIN.

     Professor Bruce C. Heezen of Lamont-Doherty Geological Observatory had
responsibility for the 1974 geological investigations at DWD-106 (Heezen, 1975)
and the 1975 and 1976 geological field studies at the low-level radioactive
waste dumpsite.  Professor Heezen died in June 1977 prior to final analysis of
the latter field studies.  This report has been assembled using field notes,
sketch maps, audiotape recordings made by Professor Heezen, and selected
photographs from the submersible activities of the 1975 and.1976 surveys.
Additional data have been added to this report data from the research files at
Lamont-Doherty Geological Observatory.  The assessments and conclusions reflect
the authors' interpretation of the available observations and facts.
                                      -1-

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                                     SUMMARY

     During 1975 and 1976 a total of eight submersible dives with DSRV ALVIN
were carried out in a relatively small region (about 2 km x 3 km) of the
radioactive waste dumpsite and were centered at 38°30'N and 72°09'W.  Six
other dives were distributed through the northern part of DWD-106 near the
boundary of the continental rise/continental slope.

     The lower continental slope is incised by submarine canyons debouching
into the northern side of DWD-106.  Canyon walls are steep (up to 50°) and
display outcrops of strata made up of calcareous marl stones, grainstones, and
siliceous mudstones.  The upper continental rise is incised by narrow meandering
channels.  One of them passes through the radioactive waste dumpsite and was
surveyed in detail during the 1976 diving schedule (Heezen and Dyer, 1977).

     On the upper continental rise the local terrain is relatively flat but
studded with numerous tracks, trails, holes, and mounds of biological origin.
The sediment carpet is composed of a gray silty-clay referred to in the
pre-1970 literature as lutite.  Sediment cores display bioturbation effects
and appear rather homogeneous in lithology and lack distinct bedding.  The
carbonate in the dumpsite area ranges between 30% and 43% and averages 37%.
Essentially all of the carbonate is biogenous with foraminifera characterizing
the sand and upper silt-size fractions, and coccoliths characterizing the  lower
silt and clay-size fractions (Neiheisel, 1979).

     The mineral suite averages 37% biogenous carbonate, 30% clay minerals,
2% mica, 23% quartz, 7%  feldspar, 1% detrital heavy minerals, and trace amounts
of glauconite and diatoms.  The clay mineral suite is predominantly illite
(50-60%) and generally equal proportions of chlorite and kaolinite which, when
combined, range between  12% and 30%.  Montmorillonite comprises between 5% and
10% of the clay minerals.  The heavy mineral suite is essentially a garnet-
hornblende suite with a  garnet-staurolite ratio  similar to the mineral province
on the adjacent continental shelf (Neiheisel, 1979).
                                       -2-

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     The average sediment texture of the upper and lower portions of the cores
is very uniform over the dumpsite area, with most cores characterized as
clayey-silts and a few as silty-clays.

     Pebbles, cobbles, boulders, and large allochthonous blocks (olistoliths)
were encountered on many of the dives.  Some of them are interpreted as glacial
erratics, ice-rafted into the area more than 14,000 years ago.  Others are
composed of indurated marine marls and clays of Eocene age, carried into
deepwater sites by subaqueous landslides and debris flows in relatively recent
times.   In fact, the western part of the dumpsite is a broad slump scar which
has lost tens of meters of sediment cover by creep or fTowage within the time
period since the last major interglacial 35,000 years before present (B.P.).

     Bottom currents were detected during a majority of the dives.  Five current
meters deployed between August and November 1976 recorded varying oscillatory
currents with a maximum speed of 40 cm/sec and a mean flow of 3-4 cm/sec.
During periods of highest speeds, the currents flowed in a westerly direction
(Hamilton, 1982).   Ripple marks were only detected in canyons, gullies, and  '
the thalwegs of meandering channels.  Scour moats were present around rock
outcrops and waste containers, and the moats were filled with distinctly coarser
lag deposits.

     Containers were observed in varying states of integrity.   Some of the
containers appeared to have been breached.   Encrustations of worm tubes,
anemones, and sponges were seen on the exposed concrete end of the waste
containers and were also common on outcrops of calcareous substrates,  indicating
that the abundance of attached organisms is directly related to the solid nature
of the surface of attachment.   Mobile fauna (rattail  fish,  ophiuroids,  asteroids,
euphausids, and holothurians) were observed feeding upon surficial sediment
surrounding the waste containers.   The rattail fish in particular were  attracted
to sediment plumes put into suspension by the submersible.   Sessile fauna such
as gorgonians and pennatulids were photographed as they were deflected  by
near-bottom currents, the stalked animals being most abundant in flat terrain.
The action of both animals and currents has partly but not totally obliterated
1- to 2-year-old ski marks made by the ALVIN during previous surveys.
                                      -3-

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     On the continental rise the local terrain is partly hummocky, with relief
of the hills occasionally exceeding 20-30 m.   The relief is attributed to
remnant mounds of sediment left behind on broad slump scars.   Outcrops are
common on the flanks of some of the hills and on the walls of narrow channels,
but are most pervasive along the outside bends of meanders along the course of
the channels.  Gullies on the slope are separated by steeply sloping spurs
draped with clays.  Some relict cut and fill  bedforms are seen in small outcrops
on the canyon walls where the canyon apparently cuts through older levee deposits.

                            REGIONAL GEOLOGIC SETTING

     The area delineating industrial waste dumpsite 106 (DWD-106) and the nearby
radioactive waste dumpsite covers a diverse seascape of the dissected continental
slope and the depositional terrain of the continental rise.  The juncture between
these two seafloor provinces is not particularly sharp because many of the slope
canyons continue onto the rise as channels.  Some of the channels pass entirely
through the low-level radioactive waste dumpsite and reach the lower continental
rise and the Hatteras Abyssal Plain.

     The slope canyons are evident in the bathymetric contours of Figure 1
adapted from publications of Beatch and Smith (1939), Heezen et al. (1959),
Uchupi (1965), Uchupi and Emery (1967), Pratt (1967, 1968), Holland and Bedding
(1969), Schneider (1970), Emery et al. (1970), and Emery and Uchupi (1972).
The DWD-106 and radioactive waste dumpsite are situated between the Hudson
Canyon System to the northeast and the Wilmington Canyon (sometimes called the
Brandywine Canyon (Schneider, 1970))  to the southwest.  The large east-coast
canyons indent the shelf edge and, where surveyed in extreme detail as
illustrated  in Figure 2, the canyons  display a dendritic-type submarine drainage
system.  The dendritic fabric was first recognized by Stetson (1936).  Both he
and Shepard  (1952) commented on the great  similarity of the submarine  drainage
network of the east-coast margin with a subaerial "bad!and" type  topography
characteristic of North and South Dakota.  Although  it is widely  accepted today
that the submarine features are carved and kept  sediment-free by  exclusively
subaqueous processes,  one should not  lose  sight  of the value gained by the
analogies of Stetson and Shepard as relevant to  the  landforms of  DWD-106 being
sculpted by  mechanisms which we do  not adequately understand.
                                       -4-

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                                                                 69°
                                                                          68°
                                                                                   67°
                                                                                    40°
Figure 1.   Deepsea core locations and bathymetric contours of the east coast
           continental margin.   DWD-106 and the smaller contiguous radioactive
           waste dumpsite to southeast are outlined; the small solid square
           indicates the region of detailed ALVIN submersible surveys.  Note
           the heavy incising of the continental slope by submarine canyons and
           the continuation of the larger canyon systems across the continental
           rise. _  Contours are in fathoms (1 fm = 6 ft = 1.8 m).   The dumpsite
           area is bounded to the northeast by the Hudson Canyon System and to
           the south by the Brandywine Canyon System fed from the west by the
           Wilmington Canyon.   Map is from Schneider (1970).   Dotted lines are
           survey  tracks,  primarily of R/V Atlantis and R/V Vema cruises.

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                    CONTOURS  IN

                    METERS XIOO
Figure 2.   Dendritic-type drainage pattern in Heezen Canyon  on  the  continental slope of New England   In 19J7>
           ALVIN  Dives 780, 782, and 783 showed that the slope  canyons are routes along which sed merit is actively
           transported downslope by debris flows and subaqueous avalanches (figure from Ryan et al., iy/BDj.

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 Continental  Slope

      The Atlantic continental  slope is  an area of active sediment denudation,
 especially for the region from Cape Hatteras  northward to Long Island.   Forma-
 tions which  are deeply buried  beneath the continental  shelf can be traced
 seaward  by reflection  profiling to  outcrops along the  lower slope.   Strata as
 old  as Upper Cretaceous  (65-80 million  years)  have been recovered in shallow
 cores along  the slope  in  the vicinity of  Hudson Canyon and off the Carolinas
 (Gibson  et al.,  1968;  Fleischer and Fleischer,  1971; Perry et  a!.,  1975).   A
 core (#21-38)  reported by Stetson (1949)  at a  depth of 1565 m  (855 fathoms)  in
 the  northwestern corner of DWD-106  contains material of Upper  Eocene age
 (40  million  years  B.P.).

      The  outcropping of sedimentary layers along  the slope  is  illustrated  in
 Figure 3,  taken  from Grow and  Mark!  (1977).  This  profile  has  been  calibrated
 to the Hatteras  Light  No.  1.   It shows  a  seaward  extension  of  Cretaceous age
 layers which have  been truncated by a major erosion surface  (see  stars on  the
 profile)  reaching  deep beneath  the  upper wedge  of  sediment  of  the  continental
 rise.  Other erosion surfaces  also  appear on the U.S.   Geological  Survey (USGS)
 Seismic Line #2, passing  through the northeast  corner  of DWD-106, and on USGS
 Seismic Line #5, extending southward from Martha's Vineyard.

     The extent of these  regional unconformities indicates that, a massive amount
 of sediment has been removed from the former continental margin and carried
 basinward.  One of these  unconformities is traceable by reflection profiling
 techniques to a nearby drillsite of the Deep Sea Drilling Project (DSDP Site 106;
 36°26.01'N; 69°27.69'W; 4500 m water depth) reported by Hollister and Ewing
 (1972a).   This unconformity is called Horizon A by Tucholke and Mountain (1979).
 The oldest overlying strata are Miocene in age (<25 million years) indicating
that the vast part of the thick continental rise prism of the western North
Atlantic is remarkably youthful.  The erosion surface  practically crops out at
the continental rise/slope transition just to the west of DWD-106.  Here at
DSDP Site 108 (38°48.27'N; 72°39.2'W; 1845 m water depth), Middle Eocene
 (45 million years) sediments  have been  cored at 35-75  m beneath the seabed
(Hollister and Ewing,  1972b).
                                      -7-

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                                                      IPOD/USGS  LINE

                                                  700        800        900
I
00
                                                                 rviMtiv/n
                                                                UNCONFORMITY  TERTIARY  '      DIAPR COMPLEX
                                                                            INTERVAL VELOCITIES
                                                                                IN KM/SEC
  Figure 3.   Sedimentary outcrops  on the continental  slope  east of Cape Hatteras.   The seismic profile and interpretation
              is from Grow and Mark!  (1977).   Tertiary and Cretaceous-age strata are truncated by  an erosion surface
              whose base (indicated by stars) is now buried  beneath the upper  continental rise.  More than a kilometer or
              overburden has been denuded from the continental  slope in this region.  Outcrops of  this type occur  in  tne
              	JL.I..	a.
              I)uruiwebie

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     All the aforementioned evidence emphasizes the "wasted" nature of the
continental slope province.  Submarine canyons obviously play an important role
in the progressive landward retreat of the slope.  They are not only "bypass"
routes for shelf materials enroute to the continental rise and abyssal plains,
but they are areas of continuing backcutting and denudation (Figure 4).
Erosional processes within the canyons and on the slope which accompanied
fluctuations in Tertiary sea level (to perhaps 60-70 million years B.P.) have
caused a regression in the shelf edge from 10-30 km in this area (Schlee et a!.,
1979).  Debris jettisoned into the sea as waste and landing within the confines
of submarine canyons should not be expected to remain for long (geologically
speaking) at the site of impact before being transported into greater depths
on-the continental rise apron.

     Submersible explorations carried out by Bruce C.  Heezen in Hudson Canyon
and in Oceanographer Canyon (southeast of Cape Cod) have allowed direct
observation of such erosion processes.   Recent submersible fieldwork in other
New England canyons (Ryan et al., 1978b) demonstrates that these features are
still actively incising the slope.

     The New England canyons in particular contain very narrow axial  thalwegs,
in places only a few meters in width,  with sheer walls of polished and abraded
lithified sediment.   Tidal  currents surge in diurnal  cycles up and down the
canyons,  generally with a modest net upcanyon component.   Sediment is carried
into suspension by turbulent eddies and especially by the feeding habits of
bottom dwelling organisms and grazing fish.   Diagenetic dissolution,  encrusta-
tion, and boring weakens exposed rock faces,  eventually producing their collapse
as underwater avalanches.   Talus blocks are scattered throughout much of the
canyon channels on the lower slope.   Where sand is the dominant sediment on
the adjacent continental shelf, it is  fed by current gyres into the canyon heads.
This abrasive material  is swept back and forth along the  thalweg by the cyclic
tidal currents, thereby amplifying the  effects of scouring and undercutting.

     Where mud is the dominant lithology on the adjacent  shelf,  as  is the case
in the New York Bight,  the  abrasive action of tidal  currents  is  reduced.
Photography from submersibles  indicates that  in the New York  Bight  visibility is
often less than 2 m due to  the  high degree of suspended sediment.   The  mud is being
                                      -9-

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                                                                                                 o
                                                                                                 o
                                                                                                 H
                                                                                                 CO
                                      0
 9           18



NAUTICAL MILES
27
Figure 4.   Seismic reflection profile extending across the continental  margin from the shelf edge out onto the upper

           continental rise to the south of the DWD-106 and radioactive waste dumpsite region.   Note how the canyons

           on the lower slope and upper rise have cut downward into sediment layers exposing older strata (figure

           from Schneider, 1970).

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  swept back and  forth  in each tidal cycle, and tidal currents  in excess of
  50 cm/sec have,  in fact, been measured at 700 m depth  in the  Hudson Canyon
  (Heezen, unpublished).  Since sizeable amounts of mud  drape the canyon walls
  and floor, we conclude that the sediment is not being  carried out of the canyon
  system presently at a rate greater than it is entering, and entrenchment has
  temporarily ceased.

      The biological contribution to mass-wasting cannot be overemphasized
  (Dillon and Zimmerman, 1970; Warme, 1975;  Warme et al., 1971;  Palmer,  1976;
 Heezen,  unpublished field notes).   Animal  mounds and holes are very common'in
 the organic-rich carpet of hemipelagic marls,  muds,  and mudstones  (Figure 5).
 Talus ejected from burrows is always  thickest  on downslope sides of mounds
 attesting to  a prevailing gravitational  migration of excavated material  downslope.
 Vagrant  benthos (crustaceans,  holothurians,  ophiuroids) are very abundant and
 they  are constantly creating clouds of suspended sediment.   Even the densest
 limestones  are seen to be  bored  by polychaete  worms  and bivalves,  lending to
 an eventual "swiss-cheese"  framework  that  collapses  from lithostatic overburden
 pressure and  gravity.

      The dendritic  fabric  of much  of  the canyon  networks can be  explained by
 abrasive activity primarily concentrated in the  thalweg.  The  gradual sediment
 entrenchment  results in progressive oversteepening of the local  thalweg walls.
 The mechanical  failure of the walls in turn widens the  thalweg and perpetrates
 lateral  collapse.  The whole process  erodes the slope leading to its retreat.
 The dissected  regions of the continental slope are therefore only temporary
 storage  reservoirs for contemporary sediment and/or waste dumped at sea.   In
 summary, biological, mechanical, and gravitational processes and the prevailing
 current  regime work in combination to transport materials arriving in the canyon
 network to ever greater depths on the slope and rise.

     Deep sea drilling was carried out in 1975 on the west African continental
margin on DSDP Leg 47.   There, a deep  borehole penetrated a massive erosion
surface of a configuration similar to  that which exists  on the  North American
Margin.   The drilling (Ryan et al., 1976;  Ryan  et al.,  1979) and integrated
geophysical  site surveys (Seibold and  Hinz,  1974) confirm that  more than
1 kilometer of slope sediment has been removed  in only  a few million years
                                      -11-

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Figure 5.   Holes and mounds of biological  origin on the upper continental  rise
           in the northeastern section of DWD-106 about 30 km north of the

           designated radioactive waste dumpsite.  The holothunans^Psychropotes

           depressa) in background are approximately 20 cm in length.   Photograph
           #4314 is from 1975 ALVIN Dive 591 at 38°55'N, 72°04'W,^and 2460 m
           depth   The sample basket of the ALVIN submersible is in the foreground.
                                      -12-

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 (i.e., at rates of tens of centimeters per 1,000 years).  However, such
 mass-wasting processes are intermittent.   There are relatively brief episodes
 when deep entrenchment takes place and longer intervals of not only little
 entrenchment, but even complete infilling of canyons.

      Much remains to be learned about the timing of these episodes and the
 processes at work.   Nevertheless,  there is a growing consensus within the earth
 science community that erosive phases of  the continental margin seem to have
 occurred coincident with times of  enhanced sediment bypassing from the
 continental  shelf to the continental  rise (Rona,  1973;  King arid Young, 1977).

      Lamont-Doherty submersible studies in New England  canyons (Ryan et al.,
 1978a,b)  reveal  similar discrete episodes of "cut and fill,"  the earliest
 cutting reaching back at least 40  million years  B.P.
                                                            i
      The  most recent significant entrenchment  is  Quaternary in age,  correlating
 with  the  latest  phase of northern  hemisphere glaciation  at  approximately
 18,000  years  B.P. and the  accompanying  lowering of world-wide  sea  level  (Flint,
 1971).  The magnitude of relative  sea-level  lowering along  the eastern border-
 land  has  been  estimated  to be  approximately 100 to 130 m (Milliman and Emery,
 1968; Dillon  and Oldale,  1978),  an amount  sufficient to  move the shore  line
 eastward  to the present  shelf-break (Figure 6).  The Hudson Channel on  the
 modern  shelf  had its  origin as  a subaerial stream bed (Chelminski and  Fray,
 1966).  The regression caused  large thicknesses of sediment to  be removed from
 the shelf (Garrison,  1970) and  strata as old as the Upper Cretaceous were exposed
 (Woodworth and Wigglesworth, 1934).  Because of the proximity  of the shore line
 to the  shelf edge, rivers were  no doubt capable of discharging their bedload
 and certainly their suspended  load from major floods directly  into the heads
 of the  slope canyons.  Where the shelf is  narrow as along the coast of southern
 France, muddy water may reach abyssal  depths in less than a day following river
 flooding (Groupe Estocade, 1978).  When the heads of the canyons intersect the
near-shore high-energy zone,  they capture  mud,  silt,  sand arid sometimes gravel,
boulders and man-made litter, whose downslope flowage,  creep,  and avalanching
become abrasive agents for further  downcutting (Dill,  1962).
                                      -13-

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•P-
    Figure 6.   Position of ancient shore lines on the continental shelf east of New Jersey  and Delaware   These shore
               lines existed at the time of lowered sea level during the last  ice age.   The continental slope canyons are
               thought to have undergone deep entrenchment when the shore line had mgrated out to the shelf edge as was
                   3         - „ „«„	/•££„..— f*nrn n-JIToM  M D  anrl R  N  fllnale-  19/0).
               tne case some J/KUUU     '                       vn.t.~.~----—

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  Continental  Rise

       The continental  rise is distinguished from the continental  slope by its
  more gentle  seaward gradient (Heezen et al.,  1959).   The rise is essentially a
  province of  net sediment accumulation in contrast to the slope being a province
  characterized  by denudation.

       Off the eastern  coast  of North  America the  continental  rise contains the
  thickest sediment of  the  central margin  (Sheridan,  1974;  Mayhew,  1974).  South
  of Hudson Canyon, the continental rise can be subdivided  into  an "upper  rise"
  with  regional gradients of  1:200 to  1:600 and with a  large,  broad, easterly-
  sloping  convex  surface, and a "lower  rise" with  gradients as low as 1:2500 and
  an easterly-facing concave  surface (Figure 7).

      Groups of small hummocky hills occur in the dumpsite area in the upper
 portion of the upper continental rise.  The seismic reflection profiles of these
 hills give the appearance of large allochthonous blocks (olistoliths) derived
 from slumps originating on the steeper continental slope.   Characteristic
 topographic features of the upper continental  rise are steep-walled slump scarps
 and meandering channels  that cross  their surfaces.   The lower continental rise
 is a broad,  nearly level  terrace lying at depths  generally below  4000 m (2200 fm)
 Directly south  of Hudson  Canyon  the  terrace is very smooth,  having been created
 by sediment ponding  behind a buried  outer ridge which forms  part  of the lower
 continental rise hill  complex (Asquith,  1976).  The lower  continental  rise lies
 seaward  of the  dumpsite region and is relevant to our study  because it is a
 site  of  deposition for materials which may  be  transported  from  the dumpsite
 region by channelized  turbulent  flow  and/or subaqueous  avalanches.  Some  channels
 which  meander through  the  dumpsite continue across  the  lower  continental  rise
 and through the  lower  continental rise hills province  to debouch  near  the
 northeastern limit of  the  Hatteras Abyssal Plain.

     The continental rise  lies beneath the path of the Western Boundary
 Undercurrent of the North Atlantic (Heezen et al., 1966; Schneider and Heezen
 1966; Schneider, 1970).  The boundary current (Figure 8) is part of the North'
Atlantic Deep Water (Swallow and Worthington,  1961) which flows southward
parallel  to regional  isobaths.   Its  movement,  shown in Figure 9, has been
                                      -15-

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                                  LOWER CONTINENTAL
                                      RISE
                                                 LOWER CONTINENTAL
                                                    RISE HILLS
                             LOWER CONTINENTAL
                                 RISE
                                  HATTERAS O. Rl DGE
                                    L. CONTINENTAL
                                     _     HILLS
                             tt ATTFR AS                	
                              T. CANYON      HATTERAS ABYSSAL PLAIN
                                                              RMUDA    RISE
                         BLAKE BAHAMA
                         OUTER RIDGE
                BLAKE BAHAMA
               ABYSSAL PLAIN
Fiaure 7    Bathymetric profiles across the  continental margin  of the eastern
  9         roast of the United States.  DWD-106 and the radioactnve waste
            dSSslte are siluated on Profile A in an area where the continental
            Hse Is particulaHy broad and where it can be  differentiated into
            «i »miner rise"  with a typical convex surface and a more gently
            diDDiFlower rise "  The dumpsite area straddles  the limit between
            SKpVr  rise" and the continental slope.  Vertica  exaggeration
            of the profiles is 1:100 (figure from Schneider,  1970).
                                         -16-

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Figure 8.   Section across the continental  margin passing through DWD-106 and
           the radioactive waste dumpsite.   This illustration from Schneider
           (1970) shows potential  temperature of the water column, evidence,
           magnitude,  and direction of near-bottom currents,  bathymetric profile,
           character of the acoustic echo  return from the seafloor,  and surface
           sediment characteristics.   Strong currents occur below the change in
           bottom gradient that distinguishes the "upper rise"  from the "lower
           rise."  The boundary circulation causes cold-water isotherms (<2°C)
           to intrude  onto the continental  rise.   Prolonged bottom echo sequences
           and an increase in the  sand-  and silt-sized surface  sediments are
           associated  with current-swept zones.   DWD-106 and  the radioactive
           waste  dumpsite are situated landward  (to left) and above  the Western
           Boundary Undercurrent in a region where deep-water circulation at
           present is  considerably less  vigorous.
                                     -17-

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CO
              NEW YORK
       KMS CONTINENTAL
           0.   SHELF
                            ZUJ
                            UIQ.
                            zo
        UPPER
      CONTINENTAL
          RISE
             r"ULFSTREAM
                  LOWER
           \  CONTINENTAL
            \    RISE
BERMUDA
  RISE
ABYSSAL
 PLAIN
                                SLOPE
                                WATER
                                                                     NORTH  ATLANTIC  DEEP WATER
                    NO CURRENT EVIDENCE
                    SMOOTH BOTTOM
                    (NO CURRENT DIRECTION]
                    WEAK CURRENTS

                    STRONG CURRENTS
                     VERY STRONG CURRENTS
                                                 CLEAR WATER

                                                 SLIGHTLY MUDDY WATER
                                           (a) Q  MUDDY WATER
IRREGULAR
PROLONGED
  ECHO
 STRONG ECHO
WITH CONVERGING
  SUBBOTTOM
    ECHO
                                                                ECHOGRAM
                                                               CHARACTER
               VERY STRONG SINGLE
                   ECHO
                                                                                                                          -/YYW\
                                                     PROLONGED  ECHOS WITH SUBBOTTOMS
                                    SUBBOTTOM
                                    BROAD HYPERBOLA
                                                           SINGLE ECHO WITH INTERMITTANT SUBBOTTOM

                                                                                      IRREGULAR'
                                                                                      PROLONGED ECHO
                                                                                        (OUTCROP)
          100-
                                                      ICOARSE siLT
                                                      ymg
                                                  <62.0|J

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Figure 9.   Distribution of bottom photograph stations which show evidence of
           bottom current direction and relative current speed (map from
           Schneider,  1970).   "M" designates muddy bottom.   Arrows without
           circles show current flow as determined from the tracking of
           neutrally-buoyant floats.   Contours in fathoms.   Note the persistent
           southwesterly direction of the Western Boundary  Undercurrent transport
           on the lower continental rise (below 2200 fm, or 4000 m) and the lack
           of a detectable current on the upper rise, especially near and within
           the locality of DWD-106 and the radioactive waste dumpsite.
                                      -19-

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detected by direct current measurements (Volkmann, 1962) and hundreds of
compass-oriented photographic stations (Heezen and Hoi lister, 1971).   These
photographs taken in the 1976 ALVIN survey provide distinct evidence of
current-swept and current-free zones on the bottom revealed by features such
as corrugations, ripples, crag and tail structures, furrows, and inclined stalks
of attached epifauna (Figure 10).  The most common evidence of bottom currents
is reflected in the small-scale relief features on the bottom.  Smooth, round,
mud ripples (wavelength 2-6 m) are observed in some of the photographs.  Linguoid
(tongue-shaped) and transverse ripples are bedforms most commonly seen in photo-
graphs.  Steep lee and gentle stoss slopes indicate the direction of the
unidirectional current flow to the southwest.

Nature  and Composition of the Sediment Cover

     The Lamont-Doherty deep sea  core  repository  contains  numerous cores from
the region surrounding and within DWD-106  (for example, see  station  locations
plotted in Figure 1).  The most  thorough published descriptions of a large
number  of these  cores can be found in  Ericson et  al. (1961).

     Two distinct sediment types characterize the continental  slope.   Cores
from the thalwegs of major submarine  canyons  contain coarse  elastics (sometimes
including  gravel  and large fragmented mollusk shells).  These clastic beds
generally  contain micro-  and macrofauna  reworked  and displaced from  areas  of
the shallow  shelf.  The  elastics are  in  the  process of being transported through
the canyon systems  onto  the  abyssal  plain.   Cores between  the canyons consist
of cohesive  dark greenish-gray silty-clays with  high organic carbon  contents.
These  sediments are low in  calcium carbonate,  contain  some glauconite, are rich
 in pyrite,  and sometimes are abundant in siliceous microfossils such as diatom
 frustules.   The lack of appreciable stratification in  the  silty-clay cores
 suggests  deposition under rather steady environmental  conditions  without signif-
 icant winnowing by currents.   Carbon contents in excess of 1.5% by weight are
 related to the presence of low oxygen contents in the  mid-water column along
 the continental slope (see Jones, 1983).  Outcrops of pre-Recent (i.e., before
 11,000 years B.P.)  and pre-Pleistocene age claystone and shale indicate erosion
 of the slope and displacement of part of its uppermost sedimentary cover.
                                       -20-

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Figure 10.   Umbellula. a deepsea octocoral,  is shown here deflected in a westerly
            current within a narrow meandering channel  on the upper continental
            rise at 38°30.51'N, 72°09.28'W,  water depth 2788 m.   The Umbellula
            is about 40 cm in height and the current velocity can be estimated
            to exceed 10 cm/sec.   Note smoothing of the regionally flat, gray,
            silty-clay bottom.   This photograph was taken during ALVIN Dive 676
            within the low-level  radioactive waste disposal  site.
                                      -21-

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     The upper continental rise is characterized by homogeneous gray to light-
brown colored clays and silty-clays that are significantly more bioturbated
than the slope cores.  Carbonate contents in the area of DWD-106 and the
radioactive waste dumpsite approach 15% to 30% and organic carbon contents are
less than 0.4%, indicating effective biological reworking of these sediments.
Cores rarely contain pre-Pleistocene age sediment, except as clasts within
debris flow deposits.  Core A164-1, located just east of DWD-106 and the radio-
active waste dumpsite (Figure 1) and southwest of the Hudson Canyon system,
has been subjected to biostratigraphic analysis.  This core is 8.69 m in length
and consists for the most part of homogeneous silty-clay interbedded with a
few graded sand and/or silt layers, whose frequency of occurrence increases
with increasing depth within the core.  On the basis of the abundance of the
planktonic foraminifera Globorotalia menardi1, Ericson et al.  (1961) established
biostratigraphic zones which delineate Recent  (Holocene) sediments  (Z Zone)
from those of  the  last glacial epoch  (Y Zone).  The boundary between these two
Zones has been dated at 11,000 years  B.P., and it occurs at a  depth of 75 cm
in the  core.   Calculations of  sedimentation rates based upon the  location of
this boundary  yield  a rate of  6.8  cm  per  1,000 years for Holocene deposition.
The  sedimentation  rate of the  lower (glacial)  section  is greater  than  twice
that of the  upper  75 cm,  reflecting an  increase  of coarse  sediment  delivered  to
the  canyon system  through subaqueous  landslides  and  debris  flows  during  glacial
times  (Ericson et  al., 1961).

      Sediments on  the  upper  continental  rise  are essentially  hemipelagic
 deposits consisting of skeletal  material  of marine plankton admixed with clay
 minerals,  fine quartz  and feldspar derived from the  adjacent  coastal  plain  and
 shelf.   Their distinct homogeneity (Figure 11) points  toward a relatively
 tranquil environment into which coarser silts and sands have not been signifi-
 cantly advected laterally by either traction  currents  or suspension bedloads.
 For the most part, the coarse-grained sediments apparently bypass the upper
 rise by means of canyons and channels where they are confined almost exclu-
 sively to the narrow axial  thalwegs and the adjacent levees.   However, a study
 of the sediment heavy minerals and size fractions, including percent of
 sand-size inorganic minerals, at the Atlantic 2800 m radioactive waste dumpsite
 suggests that some coarse silt and sand is derived from turbidity flows spilling
                                       -22-

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Figure 11.   Lithologies of selected cores from the upper and lower continental
            rise seaward of New Jersey and Delaware.   DWD-106 and the radioactive
            waste dumpsite would be characterized by the type of surficial
            sediment found in Cores V19-1, A167-1, and A185-60 (see Figure  1)
            which is homogeneous with little distinct bedding.   Some winnowing
            is evident by the presence of thin beds of foraminiferal sands
            such as those occurring in Core V19-1.
                                      -23-

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CONTINENTAL

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                                        I	1	1	1	1	1	1

-------
 out of the channels and being transported westward by the contour currents
 (Neiheisel,  1979).

      The lower continental  rise  is  essentially covered by noticeably light-
 colored brown  to  tan clays  and silty-clays in  which there are  numerous  interbeds
 of thin well-sorted,  ungraded and often  ripple-laminated  silts and fine sands
 (Hubert,  1964;  Hollister, 1967).  A distinct feature of the  lower continental
 rise sediments  is the occurrence  of bands of bright red clay (Figure 11)  derived
 from Upper Carboniferous red  silts  of  the Gulf of  St.  Lawrence which have been
 transported  southward by the  Western Boundary  Undercurrent (Conolly et  al.,
 1967;  Needham  et  al.,  1969).

      The  overwhelmingly stratified  nature of the lower continental  rise sediments
 indicates  the presence of dynamic and  variable sediment processes  at these depths
 (Schneider,  1970).  The laminations  of well-sorted  silt are  interpreted as trac-
 tion deposits  laid  down by  the southwesterly flowing Western Boundary Under-
 current which derives  its material  from turbidity currents passing  across the
 rise enroute to the abyssal plain.   The light  color  of the sediment  provides
 evidence  of  a persistent, well-oxidized benthic boundary  layer, and  higher
 calcium carbonate contents  (see Figure 12) indicate  less  dilution of  biogenic
 skeletal material in  the pelagic  layers by clay minerals  of terrestrial origin.

                       THE  1975 SUBMERSIBLE DIVING PROGRAM

     During July and August of 1975, nine dives were conducted with DSRV ALVIN
 on the  continental margin east of the Maryland-Delaware coast  (Table 1).  The
 purpose of the program was  to study DWD-106 and the  low-level  radioactive
 waste dumpsite in order to describe the chemical, biological, physical, and
 geological characteristics of these sites and to initially determine the effects,
 if any, of dumping on the environment.

     The survey was  conducted in  an area bounded by the coordinates 38°30'N,
 39°10'N and 71°55'W and 72°34'W,  which encompasses  the lower continental slope
and the upper continental  rise provinces of the continental margin.  Dives 586,
587, 589, and 590 were made  in the shallower northwest quadrants of the dive
area where the slope is incised by small  canyons (Figure 13).   Dive 587 traversed
                                      -25-

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Figure 12   Calcium carbonate content in surface sediment samples from the
            western North Atlantic (map from Schneider, 1970).  DWD-106 and the
            radioactive waste dumpsite contain relatively low carbonate contents
            (20-30%) characteristic of continental slope and upper continental
            rise sediments which are heavily diluted by fine-grained, inorganic
            minerals transported seaward from the adjacent continental coastal
            plain.
                                       -26-

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   80°
PERCENTAGE OF
CARBONATE IN
SURFACE  SAMPLES
                             -27-

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                                    TABLE 1  -   LOCATIONS,  DEPTHS,  AND  ENVIRONMENT  OF  DSRV  ALVIN  DIVES  DURING THE 1975  NOAA-EPA
                                                SURVEY AT THE DWD-106 AND 2800 m RADIOACTIVE WASTE DISPOSAL SITES
00
I
      Dive No.   Date     Latitude

        583     7-25-75  38°33'N




        584     7-26-75  38°30'N

        585     7-27-75  38°30'N
                           Longitude

                           72°12'W




                           72°09'W

                           72°09'W
Depth        On Bottom   Leave Bottom  Bottom Environment

2786m        1153 hours  1753 hours
2806m-2829m  1338 hours  1630 hours

2818m-2832m  1216 hours  1710 hours
        586     7-28-75  38°45'N   72°31'W    2318m-2340m  1153 hours  1430 hours
587     7-29-75  38°50'N   72°34'W    2027m-2148m  1100 hours  1410 hours
        589     7-31-75  38°52'N   72°16'W    2400m-2452m  1339 hours  1808 hours
        590     8-1-75   38°56'N   72°26'W    1688m-1833m  1208 hours  1810 hours
         591     8-2-75   38°55'N
         592     8-3-75    39°10'N
                           72°04'W


                           71°55'W
 2440m-2477m  1050  hours   1706  hours
 1930m-1982m  0741 hours   1159 hours
Many containers, munitions, etc., scattered throughout area.  Gentle
hills, depressions, and 10 m high erosional escarpments, with abundant
encrusting organisms.  A few scattered boulders, some of which may be
glacial erratics.

Common boulders on soft gray silty-clay.

Discovered some damaged low-level radioactive waste drums, and cored
sediment in close vicinity.

Terrain relatively flat with low hummocks, mounds, and depressions of
biological origin.  An occasional small rock sighted.  Slight westerly
flowing current.

Terrain dissected by gullies some 2 to 12  m across and up to 15 m deep
or more.  Gully  floors are flat with abundant animal  life resting on
thin  layer of pale gray sediment covering  a more dense, sticky bluish
sediment below.  Canyon walls  display outcrops  of whitish marl.

Flat  terrain with few hills and  hummocks.  Little current.  Small rocks
and boulders greater than  1 m  in diameter  on sediment.  Abundant
"fairy rings."

Relatively flat at point of descent, a  few mounds, hills, and  hummocks.
Some  outcrops and projecting ledge of stiff clay.  Outcrops of indurated
light marl stone.   Some escarpments and  high spurs.

Quite flat bottom.   No ripple  marks and little  evidence of  current.
Some  scattered  rocks encrusted with sponges.  Clay outcrops.

Partly flat  and partly steep.  Some ripple marks.  Rounded  hillocks
and outcrops  of "nodular"  sediments.  Gravel and  cobble with  occasional
sponges  and  worm tubes.   A rounded marlstone was  collected  (Eocene
in age).

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Figure 13.   Locations of the 1975 DSRV ALVIN dives within the Atlantic 2800 m
            radioactive waste dumpsite (Dives 583, 584,  585)  and the adjacent
            DWD-106 (Dives 586,  587,  589,  590,  591).   This figure is an enlarged
            segment of Figure 1, with contours  in fathoms (1  fm = approximately
            1.87 m).
                                      -29-

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-oe-

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a terrain dissected by three gullies 2-12 m in width and up to 15 m deep.   The
canyon floors were quite flat and supported an abundant epifauna.  A thin layer
of pale-gray surficial sediment, overlying a,bluish sticky sediment, was covered
by faint tracks and trails made by echinoderms, holothurians, and crustaceans.
The walls of the canyons had slopes varying from 50° to nearly vertical.
Erosion of the canyon walls is evidenced by the occurrence of pieces of wall
rock, ranging in size from small fragments to slabs 2-3 m long, scattered on
the canyon floor.  Some were covered with a light dusting of sediment while
others were free of any sedimentary material.  Brittle stars, branching
gorgonians, large sponges, and other fauna were present on the canyon walls
which, in some locations, consisted of a whitish marl.

     Dive 589 in 2400-2452 mjof water took place in a region of relatively flat
terrain, with little or no current, and few hills and hummocks.  Small rocks,
cobbles, and boulders up to 2 m in diameter were seen littering the ocean floor
surface.  Asteroids, echinoids, sea feathers, and "fairy ring" markings in the
sediment were abundant, denoting extensive biological activity on the sediment
surface.

     Dive 590 encountered a few mounds, hills, and hummocks, within a relatively
flat terrain.  The sediment surface showed pits, mounds, tracks, and trails of
biological origin with echinoids, holothurians, ophiuroids, and ceranthid
anemones being fairly common.  Outcrops of indurated  light marl stone, escarpments
(up to 20 m  in relief), and high spurs were  seen.

     Dives 583,  584,  and 585 took place on the upper  continental rise at depths
around 2800  m  in the  low-level  radioactive waste dumpsite.  On Dive 583, many
containers,  munitions boxes, and other debris were seen scattered throughout  the
areas.   Surface  morphology varied during  the bottom traverse  ranging from flat
terrain  to gentle  hills and depressions with 12 m  high clay cliffs covered  by
abundant attached  fauna.  Small to  very  large  granite boulders were observed;
some  exhibited sparse attached  growth while  others were devoid of encrusting  fauna.
These  rocks  were most likely carried to  this region by ice-rafting during glacial
epochs.  Sediment  close to a radioactive  waste container was  cored on Dive  585.
A relatively flat  terrain with  relief in  the form  of  low hummocks, mounds,  and
depressions  of biological origin was traversed on  Dive 586 in a  region  slightly
                                       -31-

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north and west of the previous three dives (Figure 13).  The sediment here was
sticky and showed no ripple marks although a slight westerly flowing current
was observed.  Occasional small rocks littered the surface of the sediment.

     Dive 591 in the northeast corner of the dive quadrant transected a
featureless area of little relief.  No ripple marks were observed and there
was little evidence of an active current at the time of the dive.  As the ALVIN
submersible traversed the bottom, relief increased to 3-4 m giving the visual
impression of small hills and depressions.  Sponges were present on occasional
outcrops; some ophiuroids, holothurians, and sea urchins were observed and
photographed.

     Dive 592, north and east of the preceding dive area, was in a region of
alternating flat relief, dimpled with a few shallow depressions and mounds,
and steep relief displaying outcrops.  A 0.8 knot (40 cm/sec) current was
measured in a region of current ripples where the depressions were shallower
and the hillocks were rounded.  Outcrops of "nodular" sediment were seen which
are interpreted to be highly calcarous by analogy to rocks of similar appearance
caused by weathering in terrestrial outcrops.  Gravel and cobbles with occa-
sional attached sponges and worm tubes typified the sediment surface.  A rounded
cobble of marl stone was collected and subsequently determined to be Middle
Eocene in age.

                       THE 1976 SUBMERSIBLE DIVING PROGRAM

     During the summer of 1976, another U.S.  Environmental Protection Agency
radioactive waste dumpsite survey was conducted in the 2800 m low-level  radio-
active waste dumpsite located southeast of DWD-106.   The survey was centered
at coordinates 38°30'N, 72°09'W, a position on the upper continental rise
approximately 120 miles (190 km) east of the Maryland-Delaware coast.

     The survey consisted of five deep submersible dives employing the ALVIN to
search for a variety of radioactive waste containers disposed of in the dumpsite
area, to record the geological and biological characteristics along each dive
traverse, and to collect accurately-positioned sediment samples near low-level
radioactive waste packages.   One 80-gallon low-level radioactive waste drum was
                                      -32-

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recovered from a depth of 2819 m (Figure 14)_pn July 31, 1976.  Four bottom-
moored vector-averaging current meters were deployed, one at each of the corners
of the dumpsite area to make a 3-month measurement of the direction and speed of
bottom-water transport at a distance of 6 m above the seabed.  The mooring in
the southwest corner of the dumpsite had an additional current meter at a
distance of 96 m off the bottom.  The findings of this current meter mooring
experiment are detailed in another U.S. Environmental Protection Agency report
(Hamilton, 1982).  The principle conclusion of that report was that southwesterly
mean currents of 3-4 cm/sec were flowing near the bottom, and the low frequency
part of the spectrum was dominated by fluctuations around a 16-day period which
could be explained as bottom-trapped topographic Rossby waves with horizontal
wavelengths of about 200 km.

     The southwest corner of the Atlantic 2800 m dumpsite had been previously
examined by DSRV ALVIN in 1975.  Dives 584 and 585 during July 1975 had located
more than half a dozen radioactive waste drums partly buried  in the sediment
cover near 38°30.0'N and 72°09.3'W.  One of these drums, found at 1300 hours,
July 27, 1975, during Dive 585  was selected for the 1976 recovery operation.  The
drums sighted  in 1975 were scattered over an area of  only about 150 m in diameter.
Therefore, the 1976 field investigations required accurate navigation of the
submersible, which was accomplished using bottom-moored acoustic transponders.

     The 1976  field program comprised  five dives (676-680) between July 29  and
August  3.  The locations of the dives  are given  in Table 2,  arid the dive tracks
and  locations  are plotted in  Figure 15  (Heezen and Dyer, 1977).  The first  four
dives explored the  seabed in  the general vicinity of  two of  the 1975 dives  where
waste drums  had  been  sighted.   The final dive to the  west of the previous dives
undertook  a  lengthy  reconnaissance track parallel to  the regional contours.

      A  detailed  bathymetric  survey carried  out with  precision acoustic  naviga-
tion revealed the  radioactive waste containers to be  scattered within a broad
amphitheatre-shaped depression characterized  by  hummocky relief.  The dumpsite
was  crossed  by a rather  narrow (<100  m wide,  5-20 m  deep) channel, which  displayed
 large meanders (Heezen  and  Dyer, 1977).  The  broad  depression is  a  slump  scar
created by the downslope flowage or  creep  of  a 15 to 20 m thick  cover of  sediment
 (Embley,  1976).   The small  hills in  the dive  area  are interpreted to be remnants
                                       -33-

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      $f?pr ^ ^:~rf~?;';:
Figure 14.   Barrel #28 photographed on Dive 676, July 29, 1976, at a depth of
            2819 m.  A retrieval harness was put on the barrel in preparation
            for its recovery.   The barrel had been partly buried in the seabed
            for about 15 years.   Scour marks show a net current streaking of
            sediment in the southwest direction.  The original disturbance to
            the seabed made by impact of this waste container has been smoothed
            and mostly obliterated by the bottom current.
                                      -34-

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                                         TABLE 2  -   LOCATIONS,  DEPTHS,  OBSERVERS,  ENVIRONMENT AND OBJECTIVES OF DSRV ALVIN
                                                     DIVES OF THE 1976 EPA 2800  m RADIOACTIVE WASTE DISPOSAL SITE SURVEY
     Time of
     Arrival
Dive   on
No.   Bottom  Latitude
                    Longitude
                               Depart
                               Bottom
                        Depth  (Time)  Latitude
                    Longitude
                               Scientific
                        Depth  Observers
676  1230
     hours
        38°30.57'N  72°09.32'W  2774m  1900
                                       hours
677
678
1242
hours
1235
hours
38°30.17'N  72°09.10'W  2778m
38°30.35'N  72°09.31'W  2788m
1856
hours
1834
hours
679
1125
hours
38°30.25'N  72°09.42'W  2787m
1803
hours
680
1243
hours
38°30.15'N  72°10.71'W  2767m
1645
hours
                                       38°30.33'N  72°09.02'W  2773m   Robert  Dyer
                                                                      and
                                                                      Bruce Heezen
38°30.33'N  72°08.92'W  2805m
38°30.49'N  72°09.36'W  2788m
38°29.93'N  72°09.20'W  2780m  Robert Dyer
                               and
                Bottom Environment

                Smooth light gray silty sedi-
                ment,  pock-marked by benthic
                organisms.   Previous years
                ALVIN  sled marks still  evident.
                Some outcropping strata along
                about  5% of traverse.   Current
                about  5 cm/sec to SSW.

                Much debris lying on soft gray
                partly bioturbated sediment.
                A few  outcrops of light-
                colored marls, well-rounded.
                Crossed some hummocky terrain.
                Light  current to SSW.

                Numerous barrels and ammuni-
                tion containers scattered in
                and between some small  ravines
                cut into a silty-clay sub-
                strate.  Outcrop sampled is a
                white  chalk covered with
                sponges.
                Flat, silty-clay terrain with
                numerous tracks, "fairy rings,"
Pamela Polloni  mounds, and depressions of
                biological origin.   One large
                allochthonous boulder, riddled
                with holes and encrusted with
                hydrozoans, anemones, etc.
                White chalk outcrop sampled.
Bruce Heezen
and
Kip Durrin
Robert Dyer
and
Bruce Heezen
38°30.67'N  72°09.80'W  2765m  Robert Dyer
                               and
                               Akihiko Ito
                Flat unchanneled area to west
                of previous dives.  Gray
                silty-clay with single small
                outcrop.  Much evidence of

                benthic life.
                                                 Objective

                                                 Locate and examine radioactive
                                                 waste containers, collect envi-
                                                 ronmental samples, attach line
                                                 and pinger to waste container
                                                 for future recovery.
Attach line to radioactive
waste barrel and to retrieval
clamp.  Search for additional
barrels and conduct dye pellet
experiment.
Collect surface sediment sam-
ples with core tube at several
distances from a radioactive
waste drum.  Explore for more
containers and obtain a sample
of outcrop material.
                                                 Conduct biological survey and
                                                 collect box cores of surface
                                                 sediment.  Sample outcrop.
                                                 Search for more barrels and
                                                 collect cores for radiochemical
                                                 and infaunal analyses.

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I
00
o\
I
         MEANDERING  CHANNEL. UPPER CONTINENTAL RISE
                     ALVIN DIVES   676  -680
                        July29-Aug.3 1976
            •	• ALVIN  track
                   LULU track
              A    outcrop
          Control by bottom  deployed transponder net
          Geodetic position by LORAN -
          Isobaths in meters
   Figure 15.  Bathymetric contours (in meters) describing a meandering  channel  (orange  color)  on the upper continental
               rise observed during the 1976 DSRV ALVIN  submersible  survey  in  the  southwestern  corner of the 2800 m
               low-level radioactive waste dumpsite.  ALVIN tracks for Dives 676-680  are also shown (Heezen and Dyer,
               1977).  Navigation of the survey lines and on-bottom  traverses  of the  submersible were controlled by
               acoustic ranaina to bottom-moored transoonders.

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 of the original cover  left behind within the slump  scar.  The tracks of
 Dives 676, 677, 678, and 679 cross over these small hills and the flanks
 frequently expose strata of pre-Recent age.  Most of the outcrops were covered
 with encrusting sponges, worm tubes, hydrozoans, and anemones (Figure 16).
 Very little modern sediment was observed covering the outcrojps, suggesting that
 recent erosion has occurred in the area despite an average regional sedimenta-
 tion rate in excess of 5 cm per 1,000 yrs (Ericson et al., 1961).   This lack
 of an appreciable post-Pleistocene sediment cover is somewhat contradictory to
 the tranquil  environment observed from the submersible.

      The seabed between outcrops is composed of a smooth-surfaced  gray silty-
 clay and shows no consistent current lineation.   Sediment  stirred  up by the
 skis of the DSRV ALVIN  was  seen to move to the  southwest with a velocity of
 approximately 10-15  cm/sec,  which is  weak compared  to  currents  observed in many
 submarine canyons  on  the slope  (Ryan  et al.,  1978b), or  compared to  the Western
 Boundary Undercurrent on the  lower continental  rise.   Isolated  sedimentary
 blocks  and low-level  radioactive waste  containers lie  both  inside  and outside
 the  meandering channel  and they are  surrounded by well-formed scour  moats
 approximately 20 cm in  depth.

     Sled marks made  by ALVIN the  previous year  (1975) were discernible although
 the edges of  the sled tracks had  collapsed and had been  partly obliterated by
 currents  and  animals  (Figure 17).  The presence  of stalked filter feeders bent
 in the direction of current flow  (Figure 10) indicates that currents were
 present.   Although the  currents have been too gentle for the  generation of mud
 ripples,  they were sufficiently strong to smooth the sediment.  However, the
 thinness  of sediment cover on the outcrops as well as the presence of scour
 moats seem to indicate  that the area is periodically swept by powerful  currents.
 The smooth surface of the sediment is marred by tracks  and trails,  brittle star
 impressions, animal "volcanoes," and circles of small holes known as "fairy rings"
 (some of which cut across the previous ALVIN tracks).   Although large holothurians
were present and fresh feces  were observed, no old feces  could be detected
 suggesting that they are destroyed by bioturbation or currents.
                                      -37-

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Figure 16.   Encrusting sponges, hydrozoans, and anemones on outcrops of
            marl stone around the flank of an erosion remnant hill at 38 30.33 N
            72°09 04'W   This photograph is from ALVIN Dive 678 in the low-level
            radioactive waste dumpsite at a depth of 2778 m and shows the very
            thin dusting of recent sediment on the exposure of much older
            material.  Note the heavily bored nature of the marl stone.
                                      -38-

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Figure 17.
Partly obliterated ALVIN sled marks of previous year (1975) infilled
by darker sediment.  Note the fractured and friable nature of a
semi-compacted disturbed light-colored silty marl.   Rattail fish in
foreground (Cpryphaenoides sp.) is approximately 35 cm in length
Photograph taken at 2778 m depth during ALVIN Dive 677 in the
low-level radioactive waste dumpsite near 38°30.28'N,  72°09.01'W.
                                      -39-

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     The abundance of fauna on the bottom demonstrates that the low-level
radioactive waste dumpsite is a biologically active area.   The most common
organisms observed were sponges, worms, gorgonians, ophiuroids, asteroids,
decapods, rattail fish (Corvphaenoides sjx), tunicates, sea pens, anemones,
and holothurians.  Rattail fish were attracted to the sediment stirred up by
the ALVIN and were often observed to be feeding on sediment resuspended by the
submersible (Figure 18).  Occasional similar behavior was also noted in various
starfish and shrimp.

      Encrusting  organisms were  scarce  on many of the drums although outcrops
in  the  area were covered with such  organisms.  The scarcity of encrusting  fauna
may be  attributed to  either  flaking rust on the surface of some  containers which
does not provide a firm substrate for  attachment,  or  to the inhibition of
encrusting organisms  by corrosion products.   Encrustations were  generally
observed to be more common  on the exposed  concrete end of the containers  than
on  the  flaking metal  sides.

      The southeast corner of DWD-106 and the  north,  central,  and western
 portions of the low-level  radioactive waste dumpsite are  partly  littered  with
 allochthonous blocks of a wide range of sizes composed of indurated sedimentary
 material carried into the area by subaqueous  landslides  (i.e., debris flows).
 Several blocks were encountered during Dives  676 and 678, particularly one
 massive block several meters in diameter at 38°30.43'N,  72°09.18'W (Dive 676)
 which  is shown  from two vantage points in  Figure 19.  Another somewhat smaller
 block  sampled during Dive 678  consisted of calcareous grainstone of Middle
 Eocene age (40-43 million years  B.P.).  Based on the  examined fauna! content
 and sediment  composition, the  grainstone was most likely laid down originally
 in an  outer-shelf, high-energy environment and subsequently  carried to the
 deeper depths of the dumpsite  area.

      The  allochthonous blocks  and other  substrate outcrops (particularly  along the
 wall of the  meandering channel)  act as strong  acoustic targets  for the forward-
  looking CTFM (Continuous  Transmission, Frequency  Modulated)  sonar aboard  the
  ALVIN. These blocks lie on and within a semi-firm  silty-clay and range  in  size
  from pebbles to masses larger than the ALVIN submersible itself.   Many of them
  are buried to a depth of about half their diameter  which is  not greatly  different
                                        -40-

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Figure 18.   Sled marks on the seabed made by DSRV ALVIN and photographed during
            Dive 678 at a depth of 2780 m in the low-level radioactive waste
            dumpsite.   Rattail  fish (Coryphaenoides sp.) were commonly observed
            to feed within the sediment which had been freshly disturbed during
            the ALVIN traverse.
                                      -41-

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Figure 19.   Large sub-rounded olistolith lying partly buried within a slump
            scar at the 2800 m low-level radioactive waste dumpsite.   This
            allochthonous block of marl, photographed at 2775 m on ALVIN Dive 676,
            is several meters in diameter and only lightly dusted with sediment.
            It and numerous other similar blocks were carried into the area in the
            recent past by a subaqueous landslide originating on the continental
            slope some 60 to 70 km to the northwest.   Note the numerous small
            attached translucent alcyonaceans, Eunephthya fruticosa,  particularly
            evident on the top surface of the marl block in the upper photograph.
                                      -42-

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from the radioactive waste drums that were jettisoned into the area from the
sea surface.

     Tube cores taken near the drum encountered on Dive 678 and selected for
recovery could be readily inserted into the silty-clay up to their total
length of about 40 cm.   The cores were, however, somewhat difficult to extract,
suggesting that the clay there has a relatively high cohesive strength.

     Most of the drums and some of the allochthonous blocks contained no
sediment film or only a very thin dusting.  The lack of sedimentation on the
tops of the drums is probably caused by the same currents which have scoured
broad moats around them.  These moats contain coarse-grained lag deposits which
give the sediment cover a locally darker texture (Figure 20).  In all photo-
graphs of drums studied, the metal surfaces were rusted, with flakes of rust
peeling away and littering the adjacent sediment surface with an orange film
(Figure 20).  In the vicinity of the drums the bottom mud seemed browner than
usual -- a feature which might be the result of the deposition of rust flakes
from the surface of the drums.  The rust in the sediment seems to be oriented
in a southwesterly direction which correlates with the prevailing current
direction.  The rust variably caused a discoloration of the sediment to a
distance of 30 to 50 cm from the containers.
                                       -43-

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Figure 20.   Example of an erosional moat around a corroded and partly buried
            drum of radioactive waste encountered at 2774 m during ALVIN Dive 676.
            Flaking of rust has stained the adjacent surface sediment.   The moat
            has collected a distinctly coarser-textured lag deposit of winnowed
            pteropod tests and fine gravel, swept in streaks in a southwesterly
            direction along with the iron oxide flakes.
                                      -44-

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                          CONCLUSIONS AND RECOMMENDATIONS
 Conclusions
      DWD-106 and the adjacent 2800 m low-level  radioactive waste dumpsite
 occupy a seascape subject to flushing by major  natural  disturbances  such as
 subaqueous  avalanching,  debris flows, and  turbulent gravity-propelled sediment
 suspensions.   The few available piston cores  from the  Lamont-Doherty repository
 which have  been  recovered from this area indicate an intact Holocene section,
 partly winnowed,  but not removed by slumping.   Seismic  profiles  show extensive
 gullying which,  in the slope area,  has cut down into 50 million  year old hori-
 zons  exposing them as outcrops.   The extensive  denudation  of the continental
 slope and uppermost rise is  confirmed by deepsea drilling  at DSDP Site 108,
 immediately to the west  of the dumpsite area.   Low-level radioactive waste
 packages, ammunition boxes,  and other debris  resting on the seafloor could be
 subject to  remobilization seaward by flushing events.   Submersible surveys
 showed the  present environment to be both  locally eroding  (base  of escarpments,
 moats  around  outcrops, thalwegs  of  gullies  and  channels) and locally depositing.-
 The study of  piston  cores  indicates  rates  of sedimentation  exceeding 5 cm per
 1,000  years.   Hence,  many  of the  waste  packages  could be buried  or nearly
 buried in some 20,000 years.

     Despite  the  inevitability  of shallow burial  of  objects  through  sediment
 deposition, portions  of  the  low-level radioactive waste dumpsite could be exhumed
 by another  debris  flow of  the magnitude which created the slump-scar character-
 istic  of  the  1976  dive area,  where 10-20 m of sediment were  removed.

 Recommendations

     The dumpsite area should be more systematically sampled by long cores
 (5 m or more  in length) and/or subsurface drilling.  There is a need for
comprehensive stratigraphic studies to measure rates of sediment accumulation,
the extent of contemporary winnowing of sediment, and,  in particular, the
frequency of past episodic events which upon reoccurrence will scatter and/or
bury debris littering the dumpsite area.  The cores need to have a record of
at least 100,000  years and preferably 500,000 or more years in order  to  provide
                                      -45-

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some statistical insight into the repetition and nature of strati graphic
unconformities that are the record of natural flushings.   Studies  should
include biozonation, isotopic and paleomagnetic stratigraphy, radon and thorium
geochemistry, and 14C radiochronology.

     Much additional accurately-navigated bathymetry and near-bottom, side-scan
sonar profiling should be accomplished in order to work out the areal distribu-
tion of gullies, meandering channels, slump scars, and remnant hills.  A high
priority would  be to request the cooperation of the Oceanographer of the Navy
to provide a multi-beam sonar survey  of the dumpsite area.

     As a long-range objective we recommend  instrumenting the dumpsite area
with seismic monitors, tilt-meters, radiation counters, and  nephelometers to
permit recording of natural disturbances over the period of  decades.  There is
little likelihood of witnessing  flushing events during 6-hour submersible dives
or  even for  the few months' recording capability of conventional,  self-powered,
bottom-moored  instruments  retrieved by acoustical release mechanisms.
                                       -46-

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                                 UNRESOLVED PROBLEMS

       Many  large  olistoliths were  seen  to  be  resting  on  the  seabed  somehwat  less
  deeply  submerged in  the  sediment  than  low-level  radioactive waste  drums.  How-
  ever, there  is no collaborating evidence  that the  olistoliths arrived  into  the
  site  subsequent  to the initial dumping of waste  packages.   The  lack of appreci-
  able  burial  of the olistoliths is puzzling,  since  they  probably originated  by
  downslope avalanching either from submarine  canyons  or  from more proximal slump
  scars.  It is possible, but unproven, that the olistoliths were transported by
  bottom-hugging fluidized debris flows and therefore  not impacted into  the seabed.
  The time of movement and mechanism of emplacement of various allochthonous
  blocks of assorted size is intimately related to poorly-understood processes
  capable of flushing the waste out of the dumpsite area to other repositories
 on either the lower continental rise or abyssal  plain.

      Corrosion of the metal  containers  produces  a vertical  streaking of iron
 oxides in the sediment at the  ends of the  barrels.   If the  containers  had been
 disturbed during  residence on  the  seabed,  one should  expect to  see  generations
 of streaking  at different angles  to  the vertical.   None  of  the  audiotape
 commentaries  of Bruce C.  Heezen made during the ALVIN dives  lend insight  into
 this  possibility  (Heezen,  1975-76).

      Olistoliths  and  remnant hills were rather commonly  observed  in the 2800 m
 low-level radioactive waste dumpsite  where a  broad  amphitheatre-shaped  slump
 scar  has been  mapped  (Figure 15).  Are the olistoliths associated with  the slump
 scar  and were  these blocks torn from  place during the slumping event?   Large
 blocks were observed  in the northwestern sector of the low-level radioactive
 waste  dumpsite, but neither detailed  bathymetry nor side-scan sonar records
 are available  to  reveal if slump scars are also present at shallower depths
 A correlation  of  blocks with slump scars is important to establish since the
 presence of blocks (readily visible from submersibles  and bottom photographs)
 is perhaps easier to detect than the slump  scars.   Waste containers  in areas
of existing slump  scars cannot be considered to be permanently  deposited at
those sites.                                                  :
                                      -47-

-------
     A meandering, anastomosing channel was mapped where it crosses a slump
scar.  The presence of the channel raises the question of whether the slope
failure of high-porosity and rapidly-deposited sediment of the channel levees
was the cause of the meandering and anastomosing nature of the channel in this
region, or whether the channel sought out an already existing slump depression
as a more optimum route into deeper water environments.  Lack of detailed
bathymetry prevents estimation of the extent to which the upper continental
rise is dissected by channels.  Since channels are bypass routes, waste
containers along their course are subject to movement and extensive mechanical
abrasion  during brief but  high-energy,  turbulent  flows.

     Numerous  submarine canyons  incise  the  continental  slope  in the  northern
and  western  portions  of DWD-106.  Small-scale  gullies,  ravines, and  spurs  were
conspicuous, especially during  Dives  587 and 590  farthest  landward on the  slope.
Although  present  bathymetric data are insufficient to resolve details of the
morphology of these canyons and gullies, analogies to better-surveyed canyons
 along the margin  of New England suggest that they may display a  dendritic
 pattern.   Such a pattern  would imply a deep subaqueous process of headward
 erosion.   One likely causal agent for this process is bioerosion resulting
 from boring and tunneling of crustaceans (mostly crabs) and bivalves feeding
 on substrates containing organic carbon.  Observations made during the 1975
 and 1976 ALVIN diving programs do not address sufficiently the occurrence and
 magnitude of contemporary bioerosion.   Perhaps more diving needs to  be carried
 out in the  axial parts of the canyon and gullies where the erosion is most
 extensive due to the outcropping of pre-Pleistocene  layers with carbon contents
 in  excess of  2%.   Based on  the working hypothesis that canyons are most exten-
 sively carved at times of lowered sea  level when shore lines  are  in  close
 proximity to  canyon  heads,  the  canyons within the dumpsite region should  not
 be  expected to be  particularly  active at present.   However,  if bioerosion of
 the type documented  by Warme (1975)  and Palmer  (1976)  and of the  type which  may
 be  pervasive in  the  Hudson Canyon  is a major agent in slope  denudation, there
  is  no reason to  suspect  that the canyons are not subject to  contemporary
  flushings resulting from catastrophic failure of heavily tunneled canyon  and
  gully walls.   The very important geological question of just what is the  most
  significant process in sculpturing the submarine canyons off the east coast of
                                        -48-

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the United States is still open.  However, the present study provides some
insight into the processes which appear to have influenced the DWD-106 and
2800 m low-level radioactive waste disposal areas.
                                      -49-

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     physiography and sediments of the deep-sea basin, U.S.  Geol. Survey Prof.
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     shelves, sea-floor spreading, and eustacy inferred from the Central North
     Atlantic, Geol. Soc. Am. Bull., 84:2851-2872.

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     21(10):21-24.

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     and M. Nibbelink, 1978a, Bedrock geology of New England submarine canyons,
     Oceanologica Acta, l(2):233-254.

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     p.  905.
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                                  TECHNICAL REPORT DATA
                           (Please read Instructions on the reverse before completing)
1. REPORT NO.
  EPA 520/1-83-018
                                                           3. RECIPIENT'S ACCESSION NO.
4. TITLE AND SUBTITLE
   Geologic  Observations at the 2800-Meter
   Radioactive Waste Disposal Site and Associated
   Deepwater Dumpsite 106 (DWD-106.) in the Atlantic  Ocean
             5. REPORT DATE
               September 1983
             6. PERFORMING ORGANIZATION CODE
7. AUTHOR(S)
                                                          8. PERFORMING ORGANIZATION REPORT NO.
 Martine Dreyfus Rawson and William B. F. Ryan
9. PERFORMING ORGANIZATION NAME AND ADDRESS
  Department  of Geological Sciences
  Lament-Doherty Geological Observatory
    of  Columbia University
  Palisades,  New York  10964
                                                           10. PROGRAM ELEMENT NO.
             11. CONTRACT/GRANT NO.
              Contract No.
              68-01-3933
12. SPONSORING AGENCY NAME AND ADDRESS
  Office of Radiation Programs (.ANR-461)
  U.S.  Environmental Protection Agency
  401 M St.,  S.W.
  Washington, B.C.  20460
             13. TYPE OF REPORT AND PERIOD COVERED
               Final
             14. SPONSORING AGENCY CODE
               ANR-461
ABSTRACT
        During  1975  and  1976 a total of eight manned submersible dives with DSRV ALVIN
   were carried out  in a relatively small region of the Atlantic 2800m radioactive
   waste dumpsite  and were  centered at 38°30'N and 72°09'W.  Six other dives were
   distributed  through the  northern part of Deepwater Dumpsite 106  (DWD-106) near the
   boundary of  the continental rise/continental slope.  One of the  primary  purposes of
   these dives  was to observe the geological conditions in this disposal  region
   slightly south  of the Hudson submarine Canyon.
        The lower  continental slope was found to be incised by submarine  canyons
   debouching into the northern side of DWD-106.  The upper continental rise was
   incised by narrow meandering channels.  One of these channels passed through the
   radioactive  waste dumpsite and was surveyed in detail.
        On the  upper continental rise the local terrain was relatively flat but studded
   with numerous tracks,  trails,  holes, and mounds of biological origin.  The  sediment
   carpet was composed of a gray silty-clay.  Detailed mineralogical analysis  was
   performed.
        Boulders and large  allochthonous blocks (olistoliths) were  encountered on many
   of the dives.   Bottom currents were detected during a majority of the  dives.   Scour
   moats were present around rock outcrops and low-level radioactive waste  containers.
   These containers  were observed in varying states of integrity.
        On the  continental  rise the local terrain was partly huramocky, with relief of
   the hills occasionally exceeding 20-30m.  Based on this study the dumpsite  areas are
   considered to be  in a dynamic deepsea environment.
17.
                                KEY WORDS AND DOCUMENT ANALYSIS
                  DESCRIPTORS
b.IDENTIFIERS/OPEN ENDED TERMS  C.  COS AT I Field/Group
    ocean disposal
    low-level radioactive  waste disposal
    marine geology
    marine foraminifera
    Hudson Canyon geology
    packaging for ocean  disposal
|18. DISTRIBUTION STATEMENT
    Unlimited Release
                                              19. SECURITY CLASS (This Report)
                                                 Unclassified
                           21. NO. OF PAGES
                                61
20. SECURITY CLASS (This page)
   Unclassified
                                                                        22. PRICE
 EPA Form 2220-1 (Rev. 4-77)   PREVIOUS EDITION is OBSOLETE

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