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A
single diver can conduct a comprehensive survey with the system that the
VBRP has developed and implemented. However, safety and efficiency
considerations necessitate at least a two-man team. Each member of this
team has separate tasks and responsibilities. The surveyor mans the metal
detector and conducts the survey. He searches the grid for metallic
anomalies - indications that metals, not normally found in the sediments,
are present. It’s his job to ensure that the metal detector is working
properly and that his search of the grid is systematic and thorough. He
sets the pace of the team. The recorder assists the surveyor with
advancing their search line as the survey progresses. He’s responsible
for accurately recording the locations of any metallic anomalies that the
surveyor may encounter. He’s also responsible for completing a survey log
at the end of their dive.
The survey is slow and
methodical. In order to maintain their working visibility, the divers
must always make controlled, deliberate movements and minimize any
disturbance of the lakebed. They must be continually conscious of their
buoyancy control and of the force and direction of their kicks. These
considerations can present a challenge to even the most-experienced
divers, especially when coupled with the use of metal detectors, the
movements of lines, and the coordination of the team’s efforts.
New
survey members are often put through “dry runs” of the
survey on land. There, each team can discuss and
clearly understand the tasks each member will be performing
during their survey -
 something that isn’t possible in
an underwater environment, without the aid of expensive
communication devices. They practice the survey
pattern until it becomes second
nature, allowing them to concentrate on their buoyancy
and metal detection
once they perform the actual survey.
A "dry run" in progress.
Photo: LCMM collection
The team sets up and
follows their search pattern along the system of posts and lines that were
discussed and illustrated on the previous page. The surveyor swims along
a measuring tape that’s strung between corresponding posts on each side of
the grid. We refer to this measuring tape as the “transect tape”. The
tape doubles as a visual guide for the surveyor and as a method for the
recorder to precisely record anomaly locations.
The
team doesn’t immediately investigate the source of any
metal detector “hits”. To do so
would disturb the sediment, reduce their visibility and
hamper the continuation of their
 survey.
Instead, the surveyor carefully imbeds a small PVC post,
or “anomaly post”, into the
sediment nearby. Each anomaly post has its own unique
letter designation. The post designations
allow the divers to differentiate between numerous anomaly
sites. The recorder records both the position of
the anomaly and the letter designation of its anomaly post,
before the search continues. The anomaly post permits
the divers to advance the transect tape, proceed with
the survey, and later relocate any anomalies that they
had encountered. The team investigates the anomalies
after they have concluded their metal detection and usually
before leaving the site for the day.
Each anomaly is
investigated by hand. A survey diver will carefully attempt to
determine what the object is by feel. If he can, he records a short
description of the object and doesn’t disturb it any further. If you can
imagine sticking your hand in a deep vat of cold, thick oatmeal, then you
can imagine what it’s like for the survey divers to reach into the bay’s
sediment.
 Objects
that can’t be identified by feel are carefully removed
from the sediment for the divers
to view. The diver will record his observations
and may make underwater sketches or obtain underwater
photographs. Once this is completed, the object
is returned to where it
was found. It’s best for the artifacts to remain
in their original settings until monies are secured for
their conservation and display.
Just about any metal
object will return the electromagnetic pulses sent by the detector’s coil
and indicate a metallic anomaly. Valcour Bay is relatively clean but as
you might have already guessed, we also encounter many modern artifacts.
“Pull-tops” from soda cans might seem like an artifact to some of our
younger divers, but they’re not exactly what we’re looking for. These
“artifacts” and other modern debris are removed from the site and
discarded. In the event that we may return to a grid for further survey,
we’ll save ourselves the time of rediscovering them. A beneficial
by-product of the survey is the clean up of the bay.
 The
recorder completes a daily survey log at the dive’s end.
In addition to completing other pertinent information,
he transcribes the data he recorded at depth. The
tasks the divers performed, anomaly locations, and the
results of the diver’s investigations become part of a
permanent record. In the event that several teams
participate during a day of survey, each team’s survey
log becomes an attachment to a consolidated report.
Encountered artifacts
are also listed in an artifact inventory log. Each artifact is assigned a
particular inventory number. This designation is accompanied by a
description of the object and its location within the site. It’s from
this log that the VBRP’s master survey map is drawn.
The logs and master
survey map are compiled at the conclusion of each survey year. They are
presented to New York State Museum officials, along with an annual report.
Copies of all the logs, maps and reports are also stored at the Lake
Champlain Maritime Museum.
The survey and its
documentation are meticulous and time-consuming, but these are necessary
elements in maintaining the historical perspective of the bay’s
artifacts. It’s this preservation of historical data that is the primary
concern and standard of the state and federal agencies that oversee the
project. Over the past few years, the research team has compiled an
extensive base of data that LCMM has coupled with grant requests and
proposals for the objects’ recovery, conservation, interpretation and
display.
Click
on the thumbnail images to see a large photo.
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