June 7-8, 2010
By: Jesse Hamilton
By: Jesse Hamilton
The week began with a great amount of uncertainty. The growing threat of hazardous oil from the Deep Water Horizon disaster potentially moving into Pensacola Bay prompted the team to schedule a series of target dives around the bay and Santa Rosa sound in conjunction with the daily excavations of the Emanuel Point II site and the B-Street Schooner project. The purpose of these target dives were to locate and photographically document to the best of our abilities some of the previously discovered wreck sites scattered across the bay. The present condition of these sites were somewhat unknown and it was necessary to produce a better visual record of the wrecks. In the event damage is incurred to these sites from the looming oil situation, the photos taken would be useful tools in determining the pre-oil state of these sites.
On Monday the first target dives were preformed on the Santa Rosa Island wreck located about a mile east of Fort Pickens. The wreck site was found and photos were taken of some exposed timbers and ballast, as well as landscaping cloth which remained from previous excavations. A heavy current was noted in this area. From here the dive team moved north to attempt to locate the wreck of the Hamilton. After an unsuccessful search of a shallow area just east of Pensacola Naval Air Station the site was determined to be covered by sediments.
(Puffer fish in ballast on Rosario.)
On Tuesday, a second set of targets were investigated, beginning with the wreck of the Rhoda. This ship is situated a few miles east of the Santa Rosa Island wreck and it was located and photographed. The ship had clearly exposed hull timbers with protruding metal stanchions, along with two separate ballast piles from a previous salvage attempt years ago. After collecting photographs of that site the team moved a bit further east and closer to shore to attempt to find the wreck of the Sport. Unfortunately the GPS coordinates led to a location on the beach and after a shallow water search this site too, like the Hamilton a day before, was determined to be buried and unreachable. Overall, the target dives were successful in their intended goals and good visual evidence now exists of two more Pensacola Bay shipwrecks.
The Emanuel Point II excavations were executed with a greater urgency placed on accomplishing specific goals for the site. One of the primary objectives was to excavate the stern unit of 82N 500E well enough that an accurate map of the unit could be produced. After maps were made the hope was to have the main features of the unit, one whole gudgeon and part of another that led into an adjacent unit, fully exposed and capable of being removed from the units, possibly by the end of the week. Dredging operations were pushed into high gear with the addition of two new PVC dredge heads engineered by Professor Cook and little time was wasted in clearing away the overburden on these two days. Work was also preformed in the amidships area where some possible hull planking was exposed and bits of pottery were collected.
B-Street Schooner excavations also became a high priority for the group. On both days teams were allocated to the site to perform dredging operations focused on the stern section of the vessel. A large portion of the interior of the ship was uncovered during dredging which further exposed large yellow pine timbers as well as hull planking, iron spikes, and a large coil of still unexplainable concreted rope-like material. Numerous artifacts were hand collected from this site. Also the site proved that the technique of using sandbags to prevent underwater sediment shifting is effective. One notable drawback to the work at the B-Street site became the powerful odor of petrochemicals like diesel fuel in the sediments of the wreck. Although most likely not of any great danger, these smells made working conditions unpleasant at times. This week may prove to be one of the last weeks where all of the active sites are accessible and the team continues to work at full speed to document and preserve as much as possible within the precious little time left in the water.
By: Christopher Dewey
On Wednesday, we continued work on EP II, opening another excavation unit to the south of the other stern units to uncover the remainder of the gudgeon that was located last year. Gudgeons are mounted on the sternpost of a vessel and work with pintles attached to the rudder to provide an articulated joint that allows the rudder to move from side to side to steer the ship. Gudgeons and pintles work much like the hinge of a door. After dredging the new unit, the divers were surprised to find a second gudgeon stretching across the southern wall. The new gudgeon was significantly smaller than the first and was completely contained within the excavation unit. Continued excavation loosened the new gudgeon to the point where it could be recovered, and also revealed a large wooden plank measuring 30 cm wide and 7 cm thick. The crew at the B Street Schooner recovered a plank with saw marks and uncovered the remainder of the stern. The target diving team discovered a shrimp boat boom and cable.
On Thursday, we dredged in the amidships excavation unit on EP II and recovered lead sheathing, fish bones, and some brick material. The stern unit team completed the mapping of the two gudgeons and continued dredging in preparation for the retrieval of both gudgeons on Friday. Robin Hardy and Danny Haddock recovered a large iron-concreted, ring-shaped artifact, which was discovered outside the hull during last week’s metal detector scan. Dr. Bratten identified the object as a ringbolt used to secure lines to a deck or bulkhead. The B-Street Schooner crew continued to document the ship’s stern area using mosaic photography and hand drawings. One team of divers located the B-Street Barge; another wreck approximately 70 m north of the schooner. Seven team members conducted familiarization dives, and practiced survey techniques on the Seminole Wreck in Alabama.
Oil in the bay, oh my! On Friday, oil from the BP oil spill was reported in Pensacola Bay the day before, but the reports had the oil receding with the outgoing tide. The decision was made to scrub Friday’s planned dives and do only what was necessary in light of the oil intrusion into the bay. One team was sent to EP II and recovered both gudgeons, and a second team went to the B-Street Schooner to complete documentation of the stern. No one knew how long the bay would remain open so the dive teams had to work quickly. The divers prepared their slates and briefed the dive in the van on the way to the boat ramp and geared up on the boat ride out to the site. The first B-Street diver splashed shortly after the anchor was set and the dive flag was raised. Thankfully, the oil stayed away and the team conducted an extensive survey of the stern. The EP II team recovered both gudgeons without difficulty, and they are both resting comfortably in the UWF conservation lab.
(Field school student Jesse Hamilton with one of the gudgeons.)
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