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Core Drilling in Biscayne National Park
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Above: Core drilling on
Alina's Reef within Biscayne National Park.
Below: Map showing the location of Biscayne National Park and our well-cluster sites
(red dots).
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A project that has been in the works for several years and is one of Biscayne National Park's (BNP)
priority projects finally got underway. From June 3rd-17th, a small group of personnel from the USGS
St. Petersburg office spent long hours in Biscayne Bay and on the BNP reef tract at the north end of
the Florida Keys core-drilling and installing water-monitoring wells. Don Hickey and Chris Reich played
the role of 'tool pushers' for the full two weeks but were refreshed with the rotational assistance of
several 'roughnecks:' Bob Halley, Nate Smiley, and Russell Peterson. This fieldwork would not have gone
as well if it were not for outstanding assistance and guidance from Richard Curry (BNP Science Coordinator)
and Brenda Lanzendorf (BNP Associate Science Coordinator). They were instrumental in supplying fresh
SCUBA tanks and other materials, personal expertise of the BNP marine landscape, and a much-needed NPS
boat for our use when the motor on the USGS boat gave out—twice.
This study is being undertaken to investigate the potential for transporting contaminants in the groundwater
system out into Biscayne Bay and nearshore coral reef environments. Historically, offshore springs were
common in Biscayne Bay. Fresh ground water once boiled to the sea surface and seafarers used these offshore
springs for collecting drinking water. The forcing factor for offshore flow was high water levels in the
Everglades. After installation of the multitudes of levees and canals in the 1940s, however, subsequent
lowering of the water level has substantially altered the Everglades plumbing system. The springs now
serve as sites for salt-water intrusion.
Four drill sites were completed as clusters of multi-depth wells. The site locations ranged from mid-Biscayne
Bay seaward to the mid-reef tract (Alina's Reef). Monitoring-well depths were completed from 4.5 to 19 m
below the sea floor. Two sites were located in 0.5 to 1.5 m of water near Elliott Key and the other two
(middle Biscayne Bay and Alina's Reef) were in 3 m of water. The latter two sites required the use of SCUBA
to complete the coring and well installation. Several hours per day were spent working underwater to
accomplish our goals. Alina's Reef was a site of particular interest because it houses a hydrolab that has
in the past recorded low-salinity (fresher) waters. It is thought that 'fresher' ground water is seeping up
through the permeable patch reef and is being recorded by the hydrolab instrumentation. After the wells have
equilibrated, we will return to collect groundwater samples to determine if this is a site of groundwater
discharge.
On a side note, June 15th turned out to be an exciting day as we core drilled at Alina's Reef. Russ and Chris
were drilling and Don was working in the R/V Halimeda when it was noticed that a distress signal was coming
from a nearby vessel. It turned out the vessel was taking on water, their radio was out and bilge pumps were
not working. Don immediately took the NPS boat over to the sinking vessel and called the BNP visitor protection
officers to come and assist. Don got the people (including two little girls) off the sinking vessel onto the
NPS boat and helped stabilize the situation until the BNP officers arrived (in about 20 minutes) with a
portable pump. We heard later that the vessel was successfully towed to the dock and everyone was fine.
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July 2001
in this issue:
cover story:
Mapping Puget Sound
Biscayne Nat'l Park
Glacier Bay Cruise
Tripod Deployment
GIS Group Teaches Science
Juneteenth Celebration
Geochemical Processes
Geologic Discipline EMAC
Wetlands Meeting
Closing the Circle
Eric Thompson
NAGT Summer Interns
Woods Hole Interns
Jerry Parker Memorial
Gaye Farris Re-Elected to STC Exec Board
"Natural Gas Hydrates" Book
July Publications List
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U. S. Department of the Interior | U.S. Geological Survey
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