BAUE Mating Amtracks Project
June 2-3, 2012
Each year, BAUE conducts a large scale project that is aimed at team-building, challenging our team members, and giving back to the local community. Club members of all levels are encouraged to participate, to utilize their training and expand their personal capacities as well as the capacity of the group to work as a larger team.
The 2012 project took place at the Mating Amtracks, a well-known local dive site in Monterey Bay, where two amphibious tracked vehicles sit, one on top of the other. The project consisted of several months of planning, including a reconnaissance dive, a project meeting, two project practice days, one day of setup dives, and two days of survey and documentation dives. Participants contributed in a variety of ways, including planning, research, surface management, diving, and data processing.
The Amtracks sit in appoximately 75 feet of water, and thus all dives were within recreational limits.
Objective
The main goal of this project was to survey and produce a site plan of the Mating Amtracks, using the techniques that we learned in the 2011 NAS Archaeology class.
Some of the specific goals included:
Collect survey data points sufficient to make a 2-D top-view sketch of the Mating Amtracks (and optionally a side-view).
Generate a sketch based on the data points collected.
Research the possible origin and identity of the Amtracks.
Mentor and train new divers in the use of archaeological survey techniques.
Create a web space on the BAUE site summarizing our work.
Special Tools/Software Used
GPS housed in a waterproof container
SMB to mark the wreck position
Software (Adobe Photoshop, Adobe Illustrator, SiteRecorder, InkScape, Excel)
Wetnotes with modified NAS data collection template
Tape baselines
Collapsible rulers
Plumb bobs
Scale sticks
Bungees, spools, various clips to mark features
Project Plan
Location
The Mating Amtracks are located at 36 37.788 N 121 54.620 W, approximately half a mile north of Lovers' Point, in 70 to 75ft of water. The entire site covers around 300 square feet, and is surrounded by sand. Depending on the sea conditions, the area can be subject to surge, and the visibility is extremely variable, though 20' is typical.
The site consists of two amphibious tracked vehicles, one on top of the other. The bottom vehicle is mostly buried in the sand, while the top one is almost completely exposed, with its super-structure collapsed inside of the body. There is a rubble field on the south end of the site.
While accessible primarily by boat, the site can be reached on a well-planned scooter dive under excellent diving conditions. Since the site is quite small, commercial dive boats do not frequent this site but it is often visited by private dive boats.
Approach
Our goal was to generate a 2D top-down site plan of the top Amtrack. If time allowed, we would also generate a 2D side view of at least one of the tracks. In order to achieve this, we planned to identify and mark interesting and distinctive reference points on the wreck, upon which we would center our data collection. We would map out these reference points using the baseline-offset method, with two baselines running parallel along the rails on each side of the wreck, which would themselves be oriented to each other. We would also photograph all areas of the wreck, with scale sticks and reference points in each frame. The baseline-offset data allowed us to draw a basic map of these points, with the photographs allowing us to "connect the dots". We did not plan any sketching in the water, relying instead on the photographs to allow sketching after the fact.
Support
BAUE chartered the Escapade to support our activities for the project. As always, the crew of the Escapade was essential to facilitate timely and safe operations.
Timeline
While we frequently refer to the project as taking place on a single weekend, the entire project consisted of six months of planning and preparation, a weekend of data collection, and six more months of data processing. The rough timeline for this year's project was:
Preliminary project planning (Jan - Mar 2012)
Reconnaissance dive (Feb 2012)
Project meeting (April 2012)
Project practice days (April, May 2012)
Background research on Amtracks (April 2012 - present)
"Project weekend" - setup and data collection dives (June 2012)
Data processing; sketch, video, and report preparation (June - Dec 2012)
Dive Plans
Dives were conducted over a total of four days, including one reconnaissance dive (in February), one day of project setup, and two days of data collection. All dives were conducted from the Escapade, with the full support of the captain and crew.
Site Assessment Dive
In February, a team of divers conducted a dive on the site in order to assess the site for its potential as a project site. Beyond general assessment, the goals of this recon dive were to collect some preliminary pictures and video of the site, and take some very coarse measurements of the size of the site. These data would be presented during the project meeting in April.
Project Setup Day
A small group of divers conducted set-up dives on the site in preparation for the larger group effort on the following days.
Two teams of 3 divers completed the following objectives over three dives:
Located the wreck and set a downline.
Set and labelled 2 baseline tapes along the rails of the top Amtrack, and oriented the baselines to each other.
Identified and marked interesting survey points on the wreck.
Took photographs of the wreck before survey work had begun.
Captured GPS data from a downline positioned on one corner of the wreck.
