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Pages 65-88

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From page 65...
... Coast Guard in cooperation with the National Academy of Sciences (International Maritime Organization, 1990~. Increased petroleum production and consumption by industry and the public in the past 15 years warrants an updated analysis of the quantity and varied inputs of petroleum hydrocarbons into the marine environment.
From page 66...
... Although the categories are organized slightly differently in the two reports, the major input sources are the same. In TABLE 3-1 Input Sources in 1985 and Present Report 1985 Report Present Report Natural Sources Marine seeps Offshore production Transportation Tanker operations Dry-docking Marine terminals Bilge and fuel oils Tanker accidents Non-tanker accidents Atmosphere Municipal & Industrial wastes Municipal wastes Refineries Non-refining industrial wastes Urban runoff River runoff Ocean dumping Natural seeps Extraction of Petroleum Platforms Atmospheric deposition Produced waters Transportation of Petroleum Pipeline spills Spills (tank vessels)
From page 67...
... NATURAL SEEPS Crude oil that seeps naturally into the marine environment establishes a contaminant "background" that needs to be measured in order to determine the extent of pollution resulting from human activities, such as oil spills. This new assessment places the current global rate of natural seepage of crude oil at 600,000 tonnes per year, with a range of 200,000 to 2,000,000 tonnes per year.
From page 68...
... 68 OIL IN THE SEA III FIGURE 3-1 The sinking of the tanker U.S.S. Mississinewa AO-S9, Ulithi Lagoon, November 20, 1944.
From page 69...
... Max. Natural Seeps 160 160 80 240 600 200 2000 Extraction of Petroleum 3.0 3.0 2.3 4.3 38 20 62 Platforms 0.16 0.15 0.15 0.18 0.86 0.29 1 Atmospheric deposition 0.12 0.12 0.07 0.45 1.3 0.38 2 Produced waters 2.7 2.7 2.1 3.7 36 19 SR Transportation of Petroleum 9.1 7.4 7.4 11 150 120 260 Pipeline spills 1.9 1.7 1.7 2.1 12 6.1 37 Tank vessel spills 5.3 4.0 4.0 6.4 100 93 130 Operational discharges (cargo washings)
From page 70...
... 3The 20 percent factor applied to develop an maximum estimate is somewhat subjective and reflects the committee's confidence in the reporting of spills, the completeness of available databases, and a recognition that 97 percent of the total spill volume captured by these databases comes from spills that exceed 100 gallons. The likelihood that a spill much larger than that will go unobserved is, in the committee' s opinion, rather small.
From page 71...
... The minimum is 72 tonnes or 60 percent of the best estimate, and the maximum is 450 tonnes or 375 percent of the best estimated. Worldwide, the best estimate is 1,300 4The 60 percent factor used to develop a best estimate and the 375 percent factor applied to develop an maximum estimate is somewhat subjective arid reflects the comm~ttee's confidence in the data available and the methods and assumptions used to complete the calculation.
From page 72...
... Transportation of Petroleum Significant petroleum hydrocarbon inputs into the oceans from petroleum transportation activities include oil spills and operational discharges from tankers and pipelines, atmospheric deposition of volatile organic compounds (VOC) vented from tankers, and coastal facility spills.
From page 73...
... This estimate is prob5The 10 percent factor used to develop a best estimate and the 20 percent factor applied to develop an maximum estimate is somewhat subjective and reflects the committee's confidence in the reporting of spills, the completeness of available databases, and a recognition that 97 percent of the total spill volume captured by these databases comes from spills that exceed 100 gallons. The likelihood that a spill much larger than that will go unobserved is, in the committee's opinion, rather small.
From page 74...
... The computed minimum volume spilled is 6,100 tonnes/year and is based on the volume of petroleum hydrocarbons spilled per mile of pipeline per year in North American waters. Because of the uncertainty of the number of miles of pipelines existing in non-North American waters and the lack of adequate databases, the best estimate is 12,000 tonnes per year or two times the calculated amount, while the maximum spillage is estimated to be 37,000 tonnes per year or six times the calculated amount.
From page 75...
... figures by the relative movements of petroleum. On this basis, the calculated oil spillage to North American waters, from tankers is 4,000 tonnes per year (see Table 3-2~.
From page 76...
... A loss rate of 0.2 percent is applied in this study. Approximately 3.3 million tonnes of petroleum products were moved by tanker vessels in 1999, including about 2.4 7The 33 percent factor used to develop a minimum estimate and the 100 percent factor applied to develop maximum estimate are somewhat subjective and reflects the committee's confidence in the data available and the methods and assumptions used to complete the calculation.
From page 77...
... , and the maximum value is 15 The 50 percent factor used to develop a minimum estimate arid the 300 percent factor applied to develop maximum estimate are somewhat subjective arid reflects the comm~ttee's confidence in the data available and the methods and assumptions used to complete the calculation. 77 tonnes (300 percent of the best estimate)
From page 78...
... Significant petroleum hydrocarbon inputs into the oceans related to consumption of petroleum include river and urban runoff, oil spills from cargo ships, operational discharges from commercial vessels and recreational craft, and atmospheric deposition of petroleum hydrocarbons. Details concerning data sources, methodology, and computations can be found in Appendix E
From page 79...
... For the majority of the inland river basins, no usable O&G data were available, or observations were too few to be reliable. For these rivers, annual loading of O&G were calculated by multiplying the unit loads from the rivers for which data were available by the urban land area reported for the corresponding river watersheds in U.S.
From page 80...
... The calculated value of land-based inputs of petroleum hydrocarbons to North American marine waters, using the unit loadings per urban land area, is 2,600 tonnes per year (minimum) , while the best estimate is 54,000 tonnes per year and the maximum estimate is 1,900,000 tonnes per year (Table 3 2~.~2 The worldwide best estimate, as determined using the methodoli2The factors used to develop maximum and minimum estimates are somewhat subjective and reflect the committee's confidence in the data available and the methods and assumptions used to complete the calculation.
From page 81...
... As the name implies, four-stroke engines use four piston strokes for each combustion cycle including an intake stroke where fuel and air enter the combustion chamber a compression stroke combustion or power stroke and PHOTO 11 Recreational vessels, especially those with older, two-stroke engines contribute about 6 percent of the total load of petroleum entering North American waters each year. Tri-level "boat racks" along Falmouth Harbor, in Falmouth, Massachusetts, emphasize how enjoyment of recreational marine boating has expanded, leading to a shortage of slips and vessel storage facilities.
From page 82...
... OIL IN THE SEA III lated oil spillage from non-tank vessels into North American waters is 1,100 tonnes per year. This figure was applied as the minimum estimate.
From page 83...
... Fuel Oil and Bilge Oil Inputs in North American Waters Based on an analysis of transit miles of ships trading in U.S. waters and the size of their power plants, the generation of bilge oil on vessels greater than 100 GT in size transiting United States waters was estimated to be 2,820 tonnes.
From page 84...
... Factoring in Canada and Mexico, the best estimate for bilge oil discharge in North American waters is 99 tonnes per year. Similar to the worldwide estimates, the minimum and maximum values were set at one-third and three times the best estimate, respectively.~7 Operational Discharges {Vessels <100 GT)
From page 85...
... For this assessment, petroleum hydrocarbons were defined as n-alkanes with carbon lengths ranging from C~0 to C33. To develop an accurate assessment of the contaminant burden to the coastal waters via atmospheric deposition, the various coastal structure and representative contaminant loadings had to be determined.
From page 86...
... The best estimate of atmospheric deposition (wet deposition + dry aerosol deposition + gross gas absorption) of petroleum hydrocarbons into the marine waters of North America is 21,000 tonnes per year, with a minimum of 9,100 tonnes per year and a maximum of 81,000 tonnes per year.
From page 87...
... The loads trom rivers and air inputs are not being consistently monitored, and the background inputs from rivers are virtually unknown. In order to assess impacts attributable to different sources including oil spills and non-point sources, federal agencies, especially the USGS and EPA should work with state and local authorities to undertake regular monitoring of TPH and PAH inputs from air and water (especially rivers and harbors)
From page 88...
... Gasoline and lube oil inputs from older, inefficient, twostroke recreational vessels are a large marine source of petroleum hydrocarbons. These discharges are primarily gasoline and lube oil, which have high evaporation rates and low PAH OIL IN THE SEA III levels.


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