Approved Scope of On-site Investigation 2000
The first objective of on-site research during the 2000 field season will be to deploy an anchor or clump at the wreck site. Deployment of an anchor or clump capable of mooring a large Zodiac or small vessel at the wreck site will be essential to supporting more extensive on-site research. The capacity of the anchor or clump must be sufficient to moor the proposed research vessel on short scope during the slack tide and on more extended scope during the change of tide. The position of the scope should be approximately amidships and off to one side of the surviving hull remains. The location of the anchor or clump must be surveyed to prevent damage to structure or material associated with the wreck.
The second objective of on-site research during the 2000 field season will be documentation of vessel structure and associated material exposed at the wreck site. Initial documentation of the wreck site will accomplished using a high resolution digital side scan sonar. The sonar will be interfaced with a differential global positioning system (DGPS) and a computer equipped with survey software to control vessel positioning and data collection. An electronic grid will be developed to cover the remains of the CSS Alabama and the bottom surface surrounding the wreck site. Acoustic data will be systematically collected using DGPS positioning. The sonar images should provide a highly detailed image of the exposed wreck structure and any previously unidentified remains in the immediate vicinity of the hull. That imagery can be used to enhance the site map and identify additional exposed wreckage for diver identification and assessment.
Documentation will also include generation of a video and photographic record of the exposed wreck structure. Using a diver propulsion vehicle equipped to carry an underwater video, 35mm camera(s) and lights, a video and photographic record of material on the bottom surface will be made by archaeologists and divers. A baseline web connecting major features of the exposed wreckage will be used to help control systematic data collection. That same baseline web will be used to guide the development of a wreck site mosaic designed to enhance the previously developed site plan.
Archaeologists will continue the test excavation previously begun within the surviving hull in the stern. The excavation will be accomplished using 3 or 4-inch air lifts or diver propulsion vehicles (DPV). Power for the air lifts will be provided by compressed air cylinders on a Zodiac. DPV's may also be used to provide power for blowers or water induction dredges as they have proven functional during previous investigations of the wreck. Excavation will be controlled by a grid constructed of ridged or non-ridged material such as aluminum or PVC. Documentation of the excavation and recording of material exposed by excavation will be accomplished by mechanical triangulation. Material recovered from the test excavation will be documented in situ, placed in containers for transportation to the surface, cataloged, documented and packaged for shipment to the Naval Historical Center for conservation.
In addition to recovering artifacts and data that sheds light on life on the CSS Alabama, the excavation will be designed to generate information on the nature and scope of the archaeological record. Perhaps the most significant issues associated with investigation of the remains of the Alabama regard how much of the hull structure survives below the bottom surface and what is the nature and extent of the archaeological record preserved within that structure. Data from limited previous excavation suggests that preservation below the shell hash is excellent with intact features and associated artifacts with undisturbed provenience. Test excavation will also generate data concerning the difficulties of working in the dynamic wreck site environment. Previous excavation has already illustrated some of the problems associated with diver time on site and the impact of currents on excavation stability. The proposed excavation would, for the first time, employ a much more powerful and effective means of sediment removal and utilize an aluminum or sand-filled fabric structure to isolate the excavation from the currents and migrating shell hash.
Using information from the video and photographic documentation and limited temporary removal of bottom surface shell hash, an effort will be made to identify a second area of test excavation in the bow of the wreck. In one or more areas identified in the site plan and documented by additional video and photography, shell hash will be removed using induction dredges or diver propulsion vehicle adapted propwash systems. Evidence of the stem and hull remains that define the bow will be located and identified using fiberglass rods. If possible the area of the crew's quarters in the foc'c'le will be identified and the site of a proposed test excavation isolated by one of the sand filled fabric structures. That structure will be left in place to determine if it will be effective in long term efforts to isolate areas of the wreck from migrating shell hash. Excavation of the crew's quarters will be scheduled for the summer campaign of 2001.
During the 2000 campaign limited excavations will also be undertaken at the base of the propeller and at the location of the stern pivot gun. Those excavations will be designed to determine if the propeller and lifting banjo remain attached to the keel and deadwood and if the pivot gun is still associated with its carriage and truck. That information will be essential to formulating plans for recovery of both those items. Excavation will also be undertaken at the site of the aft fire pump. That excavation will be designed to clear the pump for documentation and recovery.
Recovery of several large artifacts will be undertaken in conjunction with fieldwork during the summer of the year 2000. Artifacts identified for recovery are the aft fire pump, one or more of the 32-pounder cannon and possibly their trucks, and possibly one of the two Trotman Patent anchors. After thorough documentation. recovery will be accomplished using lift bags or a combination of lift bags and lifting equipment aboard the surface support platform. Like material recovered from the test excavation, large objects will be documented in situ, prepared for transportation to the surface, raised, cataloged, documented and packaged for shipment to the Naval Historical Center for conservation.
Click on the titles below for further reading on the C.S.S. Alabama artifact recovery efforts.
Artifact Recovery Main Page
Synopsis of Previous Research
Wreck Site Environment
Description of the Vessel Remains
Approved Scope of On-site Investigation 2000
Specific Research Methodology
Surface Support Vessels
Proposed Project Schedule