Rubicon Foundation Archive ( AQUARIUS UNDERSEA LABORATORY: THE NEXT GENERATION

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1 AQUARIUS UNDERSEA LABORATORY: THE NEXT GENERATION Andrew N. Shepard David A. Dinsmore Steven L Miller Craig B. Cooper Robert 1.Wicklund National Undersea Research Center University of North Carolina at Wilmington 7205 Wrightsville Avenue Wilrnington, NC USA The Aauarius undersea laboratory is owned by the National Oceanic and Atmospheric Administration and run by the National Undersea Research Center at the University of North Carolina at Wilmington. Aquarius is now supporting saturation science missions off Key Largo, FL. The laboratory, or habitat, was designed and built in the mid-1980s. In partnership with industry, academia and government, the Center plans to upgrade systems, operating protocols, and scientific programs starting in the summer of 1996, when the laboratory will be retrieved from Conch Reef. The most significant operational change is replacement of the Mobile Support Base, a 50 foot by 100 foot life support barge moored above Aauarius, with an unmanned, state-of-the-art, life support and telemetry buoy (LSTB). The buoy will simplify operations, reduce costs, and expand science capabilities. INTRODUCTION In the last three years, NOAA's National Undersea Research Center at the University of North Carolina at Wilmington successfully operated the world's only underwater laboratory, Aquarius, in the Florida Keys National Marine Sanctuary. The Aquarius program supports scientists who live and work underwater during ten day missions to study economically important, deep water coral reefs. Living underwater and in space are similar. Whether in space or under the sea, life support equipment is needed to survive in an environment hostile to humans. Exploration, discovery, and cutting-edge scientific research of national importance routinely occur in both programs. Since 1993, the Aquarius program successfully completed 21 missions over a 32-month period in the Florida Keys. The program operated previously in a submarine canyon in the Caribbean, where 12 missions were conducted in the late 1980s. Achievements include discoveries related to the damaging effects of ultraviolet light on coral reefs, geological studies that use fossil reefs to better understand the significance of present-day changes to coral reefs, research that is rewriting the book on how corals feed, water quality studies that evaluate sources and impacts of pollution, and long-term monitoring studies of reefs to document natural ecosystem variability and the potential affects of global change. The next generation of Aquarius (Aquarius 2000) will correspond with advancements in the science program, and builds on operational strengths that include: 1. Nearly unlimited bottom time to conduct experiments and make observations; 2. Sophisticated computer and electronic capability for in situ studies; and, 3. Unique access to the ocean without restrictions typical of surface-based operations.

Lang and Baldwin (Eds.): Methods and Techniques of Underwater Research These capabilities facilitate coral reef research that could not be accomplished using conventional technology.

2 Lang and Baldwin (Eds.): Methods and Techniques of Underwater Research These capabilities facilitate coral reef research that could not be accomplished using conventional technology. Based ondata from saturation missions in 1994, Figure 1 estimates the number of days required to accomplish equivalent science objectives from the surface versus saturation. This conversion assumes a rigorous dive schedule and no weather delays, which commonly leads to canceled surface dives. A,quarius missions that span 8-10 days would take at least 40 to 60 days if conducted using surface-based technology. Few scientists have time available to spend months in the field; a 10-day Aquarius mission accomplishes the same goals. Also, at the depths worked from Aquarius, surfacebased diving is considerably more rigorous and dangerous than diving in saturation. Multiple dives from the surface produce greater fatigue and risk of decompression sickness. Comparing saturation and non-saturation diving also assumes that the work can be conducted from the surface. Aquarius provides laboratory capabilities that cannot be matched using boats Mission#, Diving Figure 1. Comparison of dive days required to complete mission objectives using saturation- versus surface-based diving procedures, based on 1994 missions: science objectives can be accomplished few to five times faster in saturation. OPERATIONALPROCEDURES: 1993 TO 1996 From September 1993 to May 1996, Aquarius operated in 20 m of water, 13km from a shore support base on Key Largo, FL. The Mobile Support Base (MSB), a 50 ft. by 100 ft. catamaran barge, provided life support and technical services. The MSB, moored over the top of Aquarius, was the habitat's original Launch, Recovery, and Transport (LRT) vessel that was reconfigured to provide life-support and technical services for saturation operations. Lift davits were removed to make room for vans that housed required services and equipment (Fig. 2). The MSB was always manned during saturation missions. Each mission required twelve support staff; a technician in the habitat; four surface-support staff on two shifts during excursions, and three staff during a shift when no excursions were allowed. Between missions the MSB was visited for routine maintenance. The aquanaut team consisted of five scientists and the staff technician. Safety procedures, included constant surveillance ("bubble watch") by the surface crew of all aquanaut excursions. Equipment, supplies, meals, and general assistance for the aquanauts were also provided by the surface crew. During Aquarius operations in Florida, there were no emergency situations that required response by topside support personnel located on the MSB or safety boats. Two aquanauts suffered Type I (pain only) Decolrnpression Sickness (DCS) that occurred during decompression at the end of the missions. Both were treated in the habitat without further complications. THE NEXT GENERATION CONFIGURATION AND SYSTEMS The Center will recover and begin refurbishment of Aquarius in Re-deployment at Conch Reef is planned for The most significant change will be the replacement of the MSB with an unmanned

Shepard et al.: AQUARIUS 2000 Life Support and Telemetry Buoy (LSTB) (Figure 3). The buoy will contain habitat support systems, including power generators and high pressure air compressors.

3 Shepard et al.: AQUARIUS 2000 Life Support and Telemetry Buoy (LSTB) (Figure 3). The buoy will contain habitat support systems, including power generators and high pressure air compressors. Other systems previously located on the MSB, such as the environmental control unit, freshwater maker and storage, - and high pressure air storage, may be located on the habitat baseplate. Shown is a cutaway view of the Aquarius Undersea Laboratory. 2 Figure 2. Aquanus operations in the Florida Keys, ; on-site Mobile Support Base (MSB) provided all support functions for the aquanauts. The buoy will be secured to the seafloor with a 3-4 point mooring system. An umbilical will connect the buoy to the habitat and be used to supply power and a communications link. On-board equipment will be linked to a master control system that will automatically start and stop certain systems as appropriate. For example, if a generator shuts down, a back-up unit will automatically start and a message indicating the action taken will be transmitted to the habitat below and to the shore base. Information that may be transmitted to the shore base via the buoy includes: real-time communications (audio, video, and written); critical habitat parameters (depth, temperature, humidity, oxygen and carbon dioxide levels, gas storage status); buoy equipment status (temperature, oil pressure, fuel level, power); diver information (location, depth, air pressure in tanks, bottom time); oceanographic data (currents, water temperature, salinity, wave height and period); and, meteorological data (barometric pressure, air temperature, wind speed and direction).

4 Lane and Baldwin (Eds.): Methods and Techniques of Underwater Research STAFFING Saturation missions will consist of four scientists and two Center habitat technicians, one more staff aquanaut than past operations. All staff aquanauts are certified in advanced EMT procedures and diving medicine. The habitat technicians will be responsible for: operation of the system including monitoring and maintaining all equipment inside and outside the habitat; serving as a support diver for aquanaut excursions when needed; controlling pressurization and decompression of the habitat; aquanaut tracking, and helping to rescue a lost, injured, or surfaced aquanaut; and, emergency medical care. AQUARIUS The next eration of Aquarius will involve use of an unmanned Life Support and?ternetiy Buoy (LSTB). Real-time data, voice, visual and written communications will be telernetered from the buoy to the shore base 13 Ion away, and to satellites for world-wide distribution. A minimum of four topside staff technicians will be on-call at the shore base throughout each saturation mission, to man the watch desk and respond to emergencies. SAFETY New staff, procedures and technologies will reduce and control risks that are unique to saturation diving, with added precautions adopted due to the reduction in permanent on-site surface systems and crew. The greatest risk is aquanaut surfacing prior to decompression. From 1966 to 1996, approximately 9,700 man-excursions were made from the Hydrolab and Aquarius seafloor habitats. In March 1984, one pair of Hydrolab aquanauts surfaced after getting lost and running out of air while on excursion off St. Croix, USVI. The protocol at that time was to retrieve the divers and recompress them in a surface decompression chamber on shore. Both divers were successfully transported and decompressed back to

Shepard et al.: AQUARIUS 2000 the surface with no residual side effects. Thus, during 30 years of NOAA saturation operations, the incident rate for accidental surfacing was 0.01%.

5 Shepard et al.: AQUARIUS 2000 the surface with no residual side effects. Thus, during 30 years of NOAA saturation operations, the incident rate for accidental surfacing was 0.01%. Surfacing may also be intentional, for example, if an aqyanaut is suffering from a life-threatening illness or the habitat must be evacuated due to an emergency. One Hydrolab aquanaut had to be evacuated due to an acute medical problem, but he was decompressed in the habitat prior to evacuation. Hydrolab was completely evacuated twice in 20 years: once due to a viewport problem, although the viewport did not fail and flooding never occurred, and once because of a hurricane. In both cases, aquanauts were brought to the surface, transported to a shore-based recompression chamber, and successfully decompressed. The Center emphasizes training and safety practices to avoid emergencies. Measures taken to reduce risk include: Participants in saturation operations are fully qualified, with extensive diving backgrounds; Aquanauts are trained before missions, based on saturation dive procedures that are described in the Center's Diving Operations Manual; Participants, aquanauts and surface support crew know the posted Emergency Assistance Plan (EAP) that summarizes prescribed responses to potential emergency situations; Excursions will be continuously monitored from the habitat and shore base using a new diver tracking system with communications; No solo diving is permitted and the distance between buddies will be monitored using the tracking system, and minimized; and, The addition of a second staff technician inside the habitat will ensure that a strong diver and DMT will always be ready to assist aquanauts. The surfacing of an aquanaut is not necessarily a dire emergency. The old NOAA Diving Manual (Jan , outlines a procedure by which aquanauts may surface, determine their location and return to depth without decompression penalty. The manual also clearly states that, in case of emergency, a saturated aquanaut's primary refuge is the habitat, not the surface. Current procedures (NOAA, 1991) for handling a surfaced aquanaut is to return them to depth in the water column as quickly as possible. The manual allows for a brief surface interval (30 seconds) for a lost aquanaut coming from 100 fsw or less, to take a bearing and submerge. The Center's present operations manual allows a maximum surface interval of fifteen minutes for aquanauts surfacing from 50 fsw, based on recommendations from Tektite I1 experiments in the 1970s (Beckman and Smith, 1972). The recommended method in the NOAA Dive Manual and foremost corrective action is to return the surfaced aquanaut to the habitat. This was the approved procedure for previous saturation operations that operated with unmanned life support buoys. New procedures will be developed that will allow up to a 30 rnin. surface interval and, thus, safe transport of saturated divers from Conch Reef to a shore-base recompression chamber. If a diving or medical emergency occurs on-site, the Emergency Assistance Plan (EAP) provides guidance for immediate response. The shore-based recompression chamber and rescue boats will be en stand-by during missions. A diving medical physician is always on-call during missions. All Center staff are CPR and First Aid certified, and DMTs are always on watch and in the habitat. A fully stocked medical locker is also on-site. New technologies will further reduce the probability of unplanned surfacing. An acoustic diver tracking and communication system will provide continuous information about each diver's location and status. A transponder net will allow precise positioning of the aquanauts relative to the habitat. This information, plus air pressures in the aquanauts' scuba tanks, will be transmitted to the habitat technicians and shore base. Built-in alarms will warn the watch desk and habitat if air is low, bottom time limits are exceeded, if aquanauts descend or ascend beyond acceptable limits, separate from their dive buddy, or wander too far from the planned work site. Corrective actions can then be immediately communicated to the aquanauts via voice or messaging on a hand-held, underwater computer console.

6 Lang and Baldwin (Eds.): Methods and Techniques of Underwater Research An audible alarm will draw the diver's attention to the display. The diver may respond using macro key entries for pre-set responses, the key pad for custom messages, or possibly by voice. Cameras will be strategically placed to monitor diver activities inside and outside of the habitat. Images will be sent, real-time to the shore base, and incorporated into UNCW's Web site. Underwater loudspeakers will allow the shore base or habitat technicians to contact the aquanauts. Strategically placed safety stations will allow aquanauts to stand inside a dry air space and communicate with one another or the habitat, and refill their scuba tanks. Alternative gas supply systems, such as rebreathers, will be tested as a means to further extend air supplies. Navigation lines will lead to and from the habitat and work sites, and will reduce the possibility of an aquanaut becoming lost and having to surface. Additional lines will mark the lateral boundaries of the work site and will be marked to show the direction back to the habitat. However, if an aquanaut gets lost, they may surface, take a bearing to the LSTB or any of the surface buoys marking the reserve air stations, and return to depth. OPERATIONAL ADVANTAGES The next generation of Aquarius operations will be more effective and efficient (Table 1). Advantages associated with the new operating plan can be divided into three main categories: reduced liability, reduced costs, and improved operational effectiveness. Liability will be reduced for the university and NOAA. The chances of a maritime accident, such as collision with other boats or mooring failure, are far less with a 15-20' diameter buoy than a 50' x 100'barge. The elimination of the MSB will reduce the potential for unauthorized boarding between missions, theft, and vandalism of equipment on the barge. One of the most routinely hazardous aspects of current operations is the transfer of personnel to and from the MSB from small vessels in rough seas. The different motions of two vessels, large and small, makes the transfer of personnel and supplies difficult, especially for individuals unaccustomed to the motion of the sea. Table 1. Comparison of present operations to the next generation, with respect to safety and cost factors. Operational factor Next generation \ Number of F via Internet Surface support staff 12 6 ~ ~ u a 12n hr. a! : w o r k ~1 Consmble delivered from surface stored in the habitat Safety features surface crew on-site better communications, diver tracking, less interaction with air/sea interface Weather Scientific capabilities, Cost of dives excursions limited under storm watch conditions and by ability to operate small boat -max. six ft. seas immediate surface support from onsite crew excursions not limited b sea state except under storm watch conditions more bottom time, longer work day, more work days, unrestricted day-night divine, improved data collection and transmission considerably less due to increased bottom time and fewer staff, however, initial investment required for technology enhancements

7 Shepard et at.: AQUARHIS 2000 Operating costs will be less. The MSB is a large vessel with a significant number of systems and equipment requiring maintenance and manning 24 hours a day during missions. The elimination of the MSB will allow Aquarius to be operated by a smaller staff of at least six and considerably less than the current team of twelve. The LSTB will require less maintenance than the MSB and support vessels, which were occasionally damaged as a result of being moored to the barge. The new operating protocols will result in increased operating efficiency and effectiveness. Aquanaut excursions will not be limited by the process of getting topside support on station. Excursions have been postponed or canceled due to topside sea conditions, although sub-sea conditions were acceptable for excursions. The operating window for saturation missions may be extended by several months since the scheduling of missions will be less weather dependent. The support buoy, diver tracking system, and underwater fill stations reduce staff working hours, fatigue, and the amount of release time accrued during missions. The planned changes will also allow the interval between missions to be decreased and more projects to be supported each year. SCIENTIFIC ADVANCEMENT The most striking improvement in operations that will affect science objectives is related to communications. The ability to communicate underwater during excursions and the ability to use voice and data transmission equipment, in real time, will make Aquarius an underwater outpost with access to the world. Marine scientists will use Aquarius as a presentation platform to capture the attention and imagination of the public about the advantages of underwater living, and the importance of marine science to coastal economies. The public will be able to interact in real-time with the aquanauts via the Internet, and real-time audio and video available from the shore base or satellites. Improved communication links will benefit the science program by providing the ability to transmit data to colleagues for review and comment, announcements can be posted related to episodic events of wide interest (e.g. upwelling, coral bleaching, reproductive events, or disease epidemics), and on a daily basis, the ability to communicate underwater while diving results in more efficient use of time. It will also be possible to control experiments from remote locations around the globe using the buoy as a receiving platform for commands that are relayed to equipment previously deployed. The use of remote sensing, using Aquarius and its buoy as a base, for oceanography will increase the value of Aquarius by providing continual information about the ocean in the upper Keys, including water temperature, salinity, current speed and direction, tides, wave height and period, and possibly a suite of other parameters including chlorophyll (by fluorescence), dissolved oxygen, and meteorological conditions. The unique combination of offshore power and continuous human presence underwater will allow new equipment tests, as well as routine maintenance of sensors and computers, that would otherwise be impossible. Human presence also permits ground truthing of experimental equipment by using conventional means to gather comparative data (especially related to biology and chemistry). The new operating protocols for the Aquarius science program take advantage of state-of-the-art communication technologies that open new windows to the oceans for people all over the world. Jason VII demonstrated that there is tremendous public interest in what we do and public support ultimately translates into program support. It is also significant that a buoy will provide scientists with even more access to the sea without restrictions related to surface-based weather problems. This means more diving per mission and more missions per year. Any measure of cost effectiveness will benefit as the amount of science supported increases. PARTNERSHIPS Many of the technological innovations that will distinguish Aquarius 2000 from all previous saturation science programs will result from partnerships between industry, academia, and government. The next generation of the Aquarius science program will forge new partnerships that will strengthen our capabilities to study the oceans using the most advanced technologies.

8 Lang and Baldwin (Eds.): Methods and Techniques of Underwater Research CONCLUSION The Aquarius undersea laboratory was moved to the Florida Keys in 1993 to help scientists address concerns and questions regarding the condition of the coral reefs. Due to the distance from shore and operating in a new environment, NURC/UNCW and NOAA chose to operate Aquarius with a surface barge, with constant vigilance by an on-site, professional crew. Based on the past three years of operations, and development of new technologies, the Center determined that a more autonomous system is. appropriate for the next generation of saturation operations, a change sanctioned by the NOAA Dive Program. Aquarius will operate safer, more effectively, and at less cost with the replacement of the manned barge with the Life Support/Telemetry Buoy (LSTB). LITERATURE CITED Beckman, E.L. and E.M. Smith Tektite 11: Medical supervision of scientists in the sea. TX Repts. On Biol. and Medicine 30(3): NOAA Dive Manual (Third Ed.) NOAA/NURP, Silver Spring, MD, p

Teaching students about how technology enables science through building Aquarius Habitats.

Lesson Plan Aquarius Technology: Building an Underwater Habitat Focus Teaching students about how technology enables science through building Aquarius Habitats. Focus Questions Why build an underwater