1. Field of the Invention
The present invention generally relates to spill containment systems and more particularly pertains to devices for confining cargo leaking from watercraft at a moorage.
2. Description of the Prior Art
Spillage of cargo from an oil tanker, whether on the high seas, near an ecologically sensitive coastline, or at dockside has an adverse effect on the environment and exposes all involved parties to substantial liabilities. Although spills at dockside typically involve orders of magnitude less oil than spills resulting from damage to a tanker while underway, the frequency of the small dockside mishaps are far greater and the pollution of a harbor environment is no less undesirable.
Various systems have been devised to prevent or minimize spillage, contain spillage, recover spillage, and/or treat spillage. None provide an effective and economically feasible means to reduce the environmental impact to an acceptable level. The magnitude of effort required to recover or treat an uncontained spill defies solution while the logistical impossibility of addressing all possible contingencies renders absolute prevention similarly unattainable. Efforts directed to containment therefore appear to offer the most potential as an effective and feasible solution. However, no systems have been disclosed that are routinely, quickly and easily deployable, are capable of positively confining a spill, and are readily implemented on an industry-wide basis in a relatively economical fashion.
The system currently most often relied upon at dockside requires the placement of floating booms around the perimeter of a tanker during on-loading or off-loading. In the event of a spill, such booms are effective to prevent a film or thin layer of oil from spreading, but such a system is substantially incapable of containing a significant volume of spillage. Although the oil does float on water, it freely passes underneath such booms once sufficient oil is present to float the booms. The fitment of a curtain-like structure, extending a short distance below such floating booms, does enhance the efficacy of such a system, but nonetheless fails to provide a structure that is capable of positively confining spillage.
Additional shortcomings relate to the effort typically required to deploy the described conventional system about the entire tanker once moored. The booms must typically be manually maneuvered into place, either from a small launch or from the deck of the tanker. A similar effort is required to remove the system when the vessel is ready for departure.