A drilling contractor has collaborated with operators, engineering firms, equipment manufacturers and a shipyard to develop the design and specifications for a mobile offshore drilling unit that is capable of working in both Arctic marine environments as well as in tropical environments. Emergency Escape and Recovery (EER) operations in an Arctic environment present unique challenges with regard to crew evacuation, equipment specification, vessel arrangement, and recovery operations for the broad theater of operations. Standard readily available solutions did adequately address the environmental and regulatory challenges. A solution was developed between equipment manufacturers and an operator and described herein. This paper addresses lifeboat operations in cold weather environments, which require special attention to life boat design, storage, location on the vessel, and recovery systems during transit and drilling operations. The specific Arctic lifeboat enhancements, Canadian State requirements, and description of the crew evacuation plan are included.
The Canadian Arctic environment introduces challenges to emergency escape and rescue operations not normally encountered in the major drilling locations of the world. The presence of ice increases the complexity of EER equipment and operations. Hull crushing, engine cooling intake blockages, and obstacles seen or not seen are some of the physical difficulties ice introduces. Canadian state regulations add to this area of uncertainty, due to a lack of familiarity that must be addressed. This paper addresses these factors on how they influence crew evacuation, equipment design, and recovery operations by demonstrating them through an Arctic drillship design and specification.
The Arctic operating locations for the vessel include the Alaskan Chukchi Sea, Alaskan Beaufort Sea, and Canadian Beaufort Sea. The environmental conditions include significant wave heights greater than that experienced in the Gulf of Mexico and ice. Ice may be present during the drilling season at any well site within these areas. Other environmental hazards include freezing fog, extended periods of darkness, freezing precipitation, and extremely low ambient temperatures. These conditions make possible a difficult worst case scenario for EER operations at the location of interest.
The drilling location may be exposed to different degrees of ice during the drilling season and during transit into and out from the well site. Ice conditions range from no ice, to slush ice, to level first year ice with multi-year ice inclusions. Furthermore, wind and waves will interact with the ice to various degrees presenting impact and crushing hazards to the lifeboat.
Temperatures in the location of interest vary in extremes. The cold weather condition presents the most difficult challenge to solve. Ambient outside temperatures may plunge to less than −50°C in the winter as shown in historical records of nearby weather stations. Crew exposure to the elements must be limited or removed when considering these low temperatures.