STRATIFIED PREHISTORIC SITES ALONG THE C&O CANAL

Stuart J. Fiedel and Stephen R. Potter MAAC March 11, 2005

Middle Atlantic Archaeological Conference

**SLIDE** In March, 2003, the Cultural Resource Group of the Louis
Berger Group, under contract to the National Park Service (NPS),
National Capital Region, began a three-year program for the
identification and evaluation of archeological resources within the
lower 59-mile segment of the C&O Canal National Historical Park, which
extends along the Potomac River from Georgetown to Sandy Hook, just east
of Harpers Ferry. **SLIDE** This work is intended to implement the
Systemwide Archeological Inventory Program for the park.
Geoarchaeological testing and archaeological surveys have resulted in
identification of 15 new sites and relocation of six previously known
sites.

We have had great success in discovery of deeply stratified prehistoric
sites on the floodplains of the Potomac, which was a primary research
goal **SLIDE**. Unlike the ubiquitous shallow plowzone sites in Piedmont
uplands, where cultural remains from the past 13,000 years are
inextricably jumbled together, these are classic layer-cake formations,
where sterile river-laid sediments separate discrete episodes of human
occupation. The deeply buried remains of camps and villages have never
been disturbed either by later prehistoric inhabitants or by historic
and recent farmers. As Joffre Coe declared in 1964, it is imperative
that we find and investigate such sites, "since that is where the
answers lie to the problems of early cultural developments in the
eastern United States."

Despite the generally acknowledged importance of such floodplain sites,
only about a dozen deep excavation projects have been undertaken to date
in the eastern US, most notably Coe's work at the Doerschuk site on the
Yadkin River, Bettye Broyles' 1971 excavation of the St. Albans Site on
the Kanawha River, and Chapman's excavations on the lower Little
Tennessee River, from 1973 to 1977. The deepest zones in all these sites
are generally Early Archaic. Al Goodyear (1999) has suggested that this
fact may indicate a widespread terminal Pleistocene or earliest Holocene
climatic and erosional event, in which southeastern rivers washed away
Piedmont sediments that might have contained cultural material older
than the Kirk horizon at ca. 9500 rcbp. The rare exceptional cases,
where the deepest cultural zone is Paleoindian, are both located in
Pennsylvania: the recently excavated 36PE16 site on the Susquehanna, and
the Shawnee-Minisink site, located on a second terrace of the Delaware
River. McNett's excavations at Shawnee-Minisink, in the 1970s, revealed
an early Paleoindian stratum (recently re-dated to 12,900 cal BP) lying
about 10 feet below the surface. A late Paleoindian or earliest Early
Archaic occupation (probably about 11,500 cal BP), characterized by
side-notched "Kline" points, lay 3 feet above the Clovis zone.

On the Potomac River, very few deeply stratified sites have been
investigated previously. In 1970, at the Monocacy site, 18FR100, a
Terminal Archaic component was found at a depth of about 10 feet; below
that were river gravels. Unfortunately, this material has never been
adequately analyzed and published. In 1995, Fiedel directed excavation
of the Shepherds Field site, located on the Potomac levee near
Shepherdstown, West Virginia. The upper component was Late Woodland, and
the lower, 1.8 meters below the surface, comprised a Susquehanna
Broadspear assemblage dated to ca. 3600 rcbp (4100 cal BP).

Surface finds of fluted points and later Archaic artifacts in the
Potomac drainage demonstrate a continuous human presence in the region
since 13,000 cal BP. Several well-known Eastern Paleoindian sites (such
as Vail, Debert, Bull Brook, Williamson), presumably macroband camps,
are quite extensive\--over 300 feet long. Paleoindian sites along the
Potomac are likely to include similar large camps, comparable in scale
to later Archaic communities. Thus, on the optimistic assumption of the
survival of intact floodplain sediments of requisite age, we hoped that,
with an intelligently designed systematic survey strategy and some dumb
luck, we could discover deeply buried sites from the 9000 years
preceding the Terminal Archaic.

Berger's geoarchaeological consultant for the C&O Canal project was Dan
Wagner. Using a 3-inch auger, Wagner was able to sample alluvial
deposits to a depth of about 11 feet. **SLIDE** But with almost 60 miles
of riverbank to cover, we had to develop a strategy for efficient
testing of selected locations of highest potential. For this, we turned
to Joffre Coe's pioneering research in the Roanoke River basin. Coe
concluded that, in Fall Zone river valleys, early Holocene sites would
be found at locations with specific characteristics:

1\) a narrow valley forms a funnel neck where there was limited space
for a campsite

2\) In narrow and rocky valleys, the high velocity of the water
prevented the development of mature meander patterns, and

3\) Fingers of resistant rock extend from the valley wall to the edge of
the river. Behind these projecting rocks, the river forms large eddies
when it is in flood and deposits sand and silt at a faster rate than
elsewhere along the narrow flood plains. Eventually these deposits
become higher than the normal flood level.

Coe also observed that deep alluvial deposits containing stratified
sites may occur where a river confluence, located just above the
narrowest point in the valley, creates eddies. Michael Stewart
(1991:100) similarly attributes the preservation of the Paleoindian zone
at Shawnee-Minisink to "slackwater deposition as a result of the
hydraulic dam effect common at stream junctions" where "The velocity of
a tributary stream with a low to moderate gradient is slowed
dramatically when it junctions with the river in flood, moving at a
greater velocity. This decrease in energy causes the tributary to dump
its sediment load. A similar process is involved in the creation of
alluvial fans by tributary streams at the junction of
floodplains/terraces and steep adjacent uplands."

Based upon a preliminary examination of USGS topographic maps, and with
Coe's model in mind, we selected 14 extensive floodplains for
geoarchaeological reconnaissance. Selection of particular locations for
auger tests was aided by our discovery, in the Library of Congress, of
very detailed maps drawn for the US Army in 1865. These showed small
tributary streams which are not depicted on the modern maps.

Wagner has tested 12 floodplains, with a total of 23 auger tests.
Seventeen of these tests produced stratigraphic sequences with multiple
buried A-horizons that indicate the past availability of stable surfaces
for human occupation. Only one of the 12 tested floodplains had no
buried A-horizons. In 13 of the 23 auger tests, Wagner recovered
charcoal or encountered fire-cracked rock that provides unambiguous
evidence of human occupation. Based upon soil weathering, he believes
that the deepest A-horizons in 4 floodplains date from the Early to
Middle Holocene; 3 are Middle Holocene; 1 is Mid- to Late Holocene, and
2 date from the Late Holocene. Based upon soils alone, Wagner was
convinced that the deepest strata at the Tuscarora Creek confluence
dated from the Terminal Pleistocene to Early Holocene.

**SLIDE** These stratified sites have generally been found where smaller
streams flow into the Potomac. At seven such confluences, inspection of
bank exposures---where the meandering tributary streams continue to eat
away the old levees and alluvial fans\-- confirmed that cultural
deposits were associated with the buried surfaces.

Now, it is obvious that one reason for the dearth of investigations of
deeply buried sites is that they are not only hard to find but also
difficult to adequately and safely expose. Once you get below 5 feet,
OSHA standards for trenching require very extensive lateral excavation
to open relatively small deep holes. Stepped excavation of stream
cutbanks proved to be an expedient approach to sampling the deep
cultural deposits at Broad Run and Tuscarora Creek.

**SLIDE** Excavations at Broad Run showed that the lower of two
A-horizons there, lying about 7 ft below surface, dates from the Late
Archaic. Several typical diagnostic artifacts of the Savannah River
Broadspear complex were found within this deposit \[**SLIDE**\]. Stone
tools from this zone were associated with abundant, well preserved
charcoal, including carbonized nutshells. Charcoal from this zone has
been dated to about 4200 cal BP *\[3800+-40 rcbp, 4290 to 4080 cal BP
(Beta-187616)\].* The upper A-horizon at Broad Run, about 1.5-2 ft below
surface, yielded Late Woodland artifacts (ca. AD 1200-1500) such as
these potsherds \[**SLIDE**\].

**SLIDE** Excavations at the mouth of Tuscarora Creek revealed a
four-horizon cultural sequence: Late Woodland at the top, Early Woodland
about 3 ft below surface, a very faint late Middle to Late Archaic
horizon at about 5.7 ft, and an Early Archaic and/or Paleoindian zone at
ca. 7 to 8 ft below surface. The Early Woodland zone can be dated to
about 3000-2500 rcbp, based upon the ceramic sherds recovered: sand- and
quartz-tempered Accokeek sherds, steatite-tempered and cord-marked
Selden Island sherds, and Marcey Creek ware, steatite-tempered,
flat-bottomed, and lacking cord-marks. The Middle Archaic zone produced
almost no artifacts, but a distinct feature with charcoal, FCR, and
calcined bone flecks dated to about 5800 cal BP \[*5110+-40 rcbp,
5740-5930 cal BP (Beta-187613)*\]. The lowest zone lacked unambiguously
diagnostic artifacts **SLIDE**. Wagner found this jasper flake and
rhyolite point at about 7 feet; we suspect that the point is Middle
Woodland, from a slumped deposit. The tip of a broken late stage biface
made of fine-grained grey quartzite, was found during excavation at 6.95
ft below surface. Unfinished and lacking a base, this biface is not
typable. A point base fragment was recovered from the screen during
excavation of level D23 (7.7 to 8 ft below surface). It is made of black
chert, and represents one corner of a corner-notched, convex-based
point, with a ground basal margin. We were excited by recovery of lithic
debitage comprising materials rarely seen in typical Archaic and
Woodland assemblages. **SLIDE** This tan or amber, translucent
chalcedony or jasper appeared to be the same stone that was used to make
this spurred endscraper, which was a surface find from 18MO10, the
Patton Turf Farm site, about 10 miles downstream. This scraper is
presumably a Paleoindian tool, so we thought there was a good likelihood
that we were dealing with a Paleoindian component at Tuscarora Creek. On
the other hand, the deep zone assemblage included, besides the yellow
and red jasper, translucent chalcedony, and grey and black chert, quartz
and a considerable amount of rhyolite, which seemed inconsistent with a
Paleoindian attribution. And then there was that point fragment...
**SLIDE** Although it was too small to be definitive, it resembled the
Kirk-like points found by Broyles (1971) in one of the deepest cultural
zones (Zone 36) at the St. Albans site. A hearth in that zone was
radiocarbon-dated to 9850+-500 rcbp, and we guessed that the Tuscarora
Creek material would be of comparable age. In fact, we soon obtained two
AMS radiocarbon ages on charcoal fragments: 9290+-40 rcbp (10,280-10,570
cal BP) and (from two inches deeper) 8360+-40 rcbp (9270-9470 cal BP)
(*Beta-187614 and 187615*). Still, we wondered if the deep zone might be
a compressed multicomponent accumulation of both Early Archaic and
Paleoindian elements. So, we opened another 2.5 by 5 ft unit on the
cutbank in the next field season. This excavation yielded more jasper
and chalcedony flakes (**4 SLIDES**). Again, no diagnostic points were
found, (**SLIDE**) but we did find this spokeshave on a red jasper
blade-like flake, which had us thinking about Paleo again. However, just
below the concentration of cryptocrystalline debitage, we found this
pebble chopper {**SLIDE**}. Such tools are never found in Paleoindian
assemblages, but they occur in association with Kirk Corner-notched
points at several sites in the Mid-Atlantic and Northeast, with dates of
about 9500 rcbp. So, putting all the evidence together, we conclude that
this is a single-component Early Archaic campsite, dating from 10,500
cal BP. Now, note that all of this material was situated just above a
cobble lens (**SLIDE**). We suspect that these cobbles represent an
Early Holocene scouring episode by the Potomac, the same event that
Goodyear has documented in many other Southeastern river valleys. It may
be a marker of the end of the Younger Dryas at 11,550 cal BP, when there
was an abrupt increase in temperature and probably also in rainfall and
consequent erosion of denuded landscapes.

**SLIDE** We close with a few thoughts about the implications of these
stratified sites for Cultural Resource Management. Having been
identified and, to some degree, delimited, the sites can be protected by
park personnel against looting or destruction by proposed development.
However, the same erosional processes that have exposed the bank cuts,
allowing access to the deepest occupation zones, also threaten to
destroy these sites in the not too distant future. Section 110 of the
National Historic Preservation Act, as amended \[*P. L. 102-575*\],
states that each Federal agency shall ensure that historic properties
under its jurisdiction and which "may be eligible for the National
Register are managed and maintained in a way that considers the
preservation of their ... archaeological ...values ... and gives special
consideration to the preservation of such values in the case of
properties designated as having National significance." Clearly, the
deeply stratified sites we have discussed are potentially eligible for
listing on the National Register, certainly at the regional level and
perhaps at the national. It is equally clear that the NPS, as part of
its legal obligation under NHPA and the 1916 Organic Act \[*P. L.
64-235*\] that established the agency, must develop and implement a plan
to stabilize these archaeological sites in order to "conserve \[them\]
... for the enjoyment of future generations."

References:

Public Law 64-235

1916 National Park Service Act of August 25, 1916.

Public Law 102-575

1992 The National Historic Preservation Act Amendments of 1992.

Tippitt, V. Ann and William H. Marquardt

1984 Archaeological Investigations at Gregg Shoals, A Deeply Stratified
Site on the Savannah River. Russell Papers, Interagency Archaeological
Services Division, National Park Service, Atlanta.