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Spills
Tank vessels and ship contribute waste to the areas surrounding in multiple ways. On top of the risk of cargo spill and emissions, tank vessels dumping overboard waste, bilge water, and other aqueous waste have a negative impact on the surrounding environment. Due to the nature of crude oil, many oil tank vessels are operated stringently to avoid spillage. Despite precaution however, oil spills are still somewhat of a commonality. In US waters alone (circa 1991), the average predicted amount of petrol products and crude oil to be spilled averaged 9,000 short tons annually. Between 1990-1999, the total chronic worldwide release of oil into the ocean averaged 270,000 tons.

Bilge Water
The discharge of bilge water is also cause for concern. Bilge water is a mixture of water, chemicals, and oil that accumulate in the lowest part of a ship's engine room. The concern of bilge water is the mixed content; bilge water often contains a variety of chemicals, detergents, and types of oils. It may contain lubricant and hydraulic oils, detergents, metals, cleaners, surfactants, as well as crude oil or petrol products. The discharge of bilge water is in small quantities, so the area affected by its content is in the immediate vicinity. Bilge water is either treated en route, or stored and brought to an onshore facility to treat. With regards to treating bilge water on ships, the International Maritime Organization requires all vessels to be outfitted with an Oily water separator outfitted with an electric eye. The legally allowable discharge limit of bilge water is 15ppm or less of oil content. It is unlawful to discharge untreated bilge water. While oil in bilge water can be treated with the use of an Oily water separator, the process for treating chemicals is more dedicated. Tests cited by Peter Tiselius (2017) involving bilge water’s effect on copepods, and concluded bilge water chemicals and oil affected copepod activity in concentrations of 1-5%, and significant mortality of these organisms were observed in concentrations of 5-10%. In areas with heavy shipping activity, constant release of bilge water may pose deadly for plankton.

Ballast Water
With the introduction of steel hulled ships, a way to stabilize and balance these vessels was required. This was achieved with the use of ballast tanks. However, the discharge of ballast water from different marine environments introduced invasive species into foreign waters. To further prevent the introduction of invasive species that threaten ecological balance, the International Maritime Organzation requires all vessels to have a ballast water treatment system and ballast water management plan. This plan goes over the vessel's procedure to handle ballast water in detail. It requires a logbook for when ballast water is discharge and treated. It is unlawful to discharge untreated ballast water worldwide.

Sound Pollution
Tankers along with shipping traffic contribute largely to sound pollution within the ocean. The noise levels produced affect wildlife and as well as their environment. Sound pollution produced by passing vessels affect a variety of species, most notably: cetaceans. Other marine life are still affected by sound pollution though, as tests show that simulated playback on species of crab and eel demonstrate the organisms reacting negatively to the sound when observed. Negative effects include distraction from feeding, increased oxygen consumption/ventilation rate, and seeking shelter. In the case of cetaceans, vessel noise interferes with their biological sonar, reducing effective foraging range. Additionally, constant sound pollution due to heavy shipping activity and traffic also induce stress into cetaceans, which rely largely on sound for communication.

Design Considerations
Following major oil spills involving crude oil tank vessels, the US Committee of Tank Vessel Design (1991) have suggested design modifications for retrofitting and redesigning vessels in order to reduce the chance of oil spilling from a vessel. Design suggestions include: double hulls, double sides, double bottoms, and flexible tank liner membranes. Though this may take years before implementation in the US fleet, the design modifications are meant to reduce spill of cargo due to accidental collision or impact of the vessel. Additionally, due to the amount of sound that ships produce as well as concerns of disturbing wildlife habitat, suggestions of retrofitting ships with noise dampening technology have been proposed. Furthermore, consideration of removal for just 15% of current sailing vessels in the US fleet has been considered. Half of noise pollution generated in the North American shipping fleet is produced by 15% of the entire fleet.