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Suggested Citation:"1 Introduction." National Research Council. 1987. Controlling Hydrocarbon Emissions from Tank Vessel Loading. Washington, DC: The National Academies Press. doi: 10.17226/1133.
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Suggested Citation:"1 Introduction." National Research Council. 1987. Controlling Hydrocarbon Emissions from Tank Vessel Loading. Washington, DC: The National Academies Press. doi: 10.17226/1133.
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Suggested Citation:"1 Introduction." National Research Council. 1987. Controlling Hydrocarbon Emissions from Tank Vessel Loading. Washington, DC: The National Academies Press. doi: 10.17226/1133.
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Suggested Citation:"1 Introduction." National Research Council. 1987. Controlling Hydrocarbon Emissions from Tank Vessel Loading. Washington, DC: The National Academies Press. doi: 10.17226/1133.
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Suggested Citation:"1 Introduction." National Research Council. 1987. Controlling Hydrocarbon Emissions from Tank Vessel Loading. Washington, DC: The National Academies Press. doi: 10.17226/1133.
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Suggested Citation:"1 Introduction." National Research Council. 1987. Controlling Hydrocarbon Emissions from Tank Vessel Loading. Washington, DC: The National Academies Press. doi: 10.17226/1133.
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Suggested Citation:"1 Introduction." National Research Council. 1987. Controlling Hydrocarbon Emissions from Tank Vessel Loading. Washington, DC: The National Academies Press. doi: 10.17226/1133.
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Suggested Citation:"1 Introduction." National Research Council. 1987. Controlling Hydrocarbon Emissions from Tank Vessel Loading. Washington, DC: The National Academies Press. doi: 10.17226/1133.
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Suggested Citation:"1 Introduction." National Research Council. 1987. Controlling Hydrocarbon Emissions from Tank Vessel Loading. Washington, DC: The National Academies Press. doi: 10.17226/1133.
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Suggested Citation:"1 Introduction." National Research Council. 1987. Controlling Hydrocarbon Emissions from Tank Vessel Loading. Washington, DC: The National Academies Press. doi: 10.17226/1133.
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Suggested Citation:"1 Introduction." National Research Council. 1987. Controlling Hydrocarbon Emissions from Tank Vessel Loading. Washington, DC: The National Academies Press. doi: 10.17226/1133.
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Suggested Citation:"1 Introduction." National Research Council. 1987. Controlling Hydrocarbon Emissions from Tank Vessel Loading. Washington, DC: The National Academies Press. doi: 10.17226/1133.
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Suggested Citation:"1 Introduction." National Research Council. 1987. Controlling Hydrocarbon Emissions from Tank Vessel Loading. Washington, DC: The National Academies Press. doi: 10.17226/1133.
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Suggested Citation:"1 Introduction." National Research Council. 1987. Controlling Hydrocarbon Emissions from Tank Vessel Loading. Washington, DC: The National Academies Press. doi: 10.17226/1133.
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Suggested Citation:"1 Introduction." National Research Council. 1987. Controlling Hydrocarbon Emissions from Tank Vessel Loading. Washington, DC: The National Academies Press. doi: 10.17226/1133.
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Suggested Citation:"1 Introduction." National Research Council. 1987. Controlling Hydrocarbon Emissions from Tank Vessel Loading. Washington, DC: The National Academies Press. doi: 10.17226/1133.
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Suggested Citation:"1 Introduction." National Research Council. 1987. Controlling Hydrocarbon Emissions from Tank Vessel Loading. Washington, DC: The National Academies Press. doi: 10.17226/1133.
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Suggested Citation:"1 Introduction." National Research Council. 1987. Controlling Hydrocarbon Emissions from Tank Vessel Loading. Washington, DC: The National Academies Press. doi: 10.17226/1133.
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Suggested Citation:"1 Introduction." National Research Council. 1987. Controlling Hydrocarbon Emissions from Tank Vessel Loading. Washington, DC: The National Academies Press. doi: 10.17226/1133.
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Suggested Citation:"1 Introduction." National Research Council. 1987. Controlling Hydrocarbon Emissions from Tank Vessel Loading. Washington, DC: The National Academies Press. doi: 10.17226/1133.
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Suggested Citation:"1 Introduction." National Research Council. 1987. Controlling Hydrocarbon Emissions from Tank Vessel Loading. Washington, DC: The National Academies Press. doi: 10.17226/1133.
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Suggested Citation:"1 Introduction." National Research Council. 1987. Controlling Hydrocarbon Emissions from Tank Vessel Loading. Washington, DC: The National Academies Press. doi: 10.17226/1133.
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Suggested Citation:"1 Introduction." National Research Council. 1987. Controlling Hydrocarbon Emissions from Tank Vessel Loading. Washington, DC: The National Academies Press. doi: 10.17226/1133.
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Suggested Citation:"1 Introduction." National Research Council. 1987. Controlling Hydrocarbon Emissions from Tank Vessel Loading. Washington, DC: The National Academies Press. doi: 10.17226/1133.
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Suggested Citation:"1 Introduction." National Research Council. 1987. Controlling Hydrocarbon Emissions from Tank Vessel Loading. Washington, DC: The National Academies Press. doi: 10.17226/1133.
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Suggested Citation:"1 Introduction." National Research Council. 1987. Controlling Hydrocarbon Emissions from Tank Vessel Loading. Washington, DC: The National Academies Press. doi: 10.17226/1133.
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Below is the uncorrected machine-read text of this chapter, intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text of each book. Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.

1 INTRODUCTION When loading their cargo tanks, tankships and barges carrying vola- tile liquids expel vapors, displaced by entering cargo or ballast. The vapors contain volatile organic compounds (VOCs), which can exacerbate respiratory conditions. Thus, the maritime emissions are part of the larger national air pollution problem. About 95 percent of tank vessel VOC emissions are from crude oil and gasoline cargoes. About two-thirds come from inland barges, and the remainder from tankships. These emissions amount to only about 0.2 per * An analysis of the impact of volatile organic compound emissions from tank barges and tankships on ozone concentrations in port areas was conducted by Booz-Allen & Hamilton, Inc. at the request of the American Waterways Operators (Booz-Allen & Hamilton, Inc., 1987b). The analysis shows that marine VOC emissions represent a small per- centage of the total VOC emissions in four selected port areas--New York/New Jersey, Houston, Philadelphia, and Los Angeles/Long Beach. In three of the port areas, each of the largest ten point sources of VOCs exceeded the total of all marine VOC emissions. Control of hydrocarbon emissions from loading and ballasting operations would produce decreases in VOC emission levels in the four port areas of from 0.03 to 2.3 per- cent. Furthermore, analysis of wind direction during exceedances indi- cates that marine sources do not normally contribute pollutants toward ozone monitors during days of nonattainment conditions. Of the four ports evaluated, only the New York/New Jersey area could possibly expect any measurable reduction in ozone levels if emissions during marine transfer operations were controlled. In contrast, the Los Angeles/Long Beach and Philadelphia marine VOC emission levels are very low in compar- ison to total VOC emission levels. Marine emission levels in Houston were higher than Los Angeles/Long Beach and Philadelphia, but prevailing wind conditions indicate that the marine VOC emission sources were not contributing to nonattainment levels. The analysis concludes that, "Marine tank vessel operations are a minor contributor of VOC emissions, particularly when viewed in context of automobiles and major industrial sources. . . . [I]n the ports of New York/New Jersey ? Houston, Philadel- phia and Los Angeles/Long Beach, controlling marine emissions would have no or minimal impact on measured ozone levels and exceedances." 7

8 cent of all volatile organic vapor emissions nationally; they are about one-tenth as great as vapor emissions from automobile fueling (EPA, 1986~. However, they may be significant locally. Under current air quality regulations, emissions from tank vessels are generally not subject to controls. However, several states, in order to meet federal air quality standards for ozone, are considering controls (see Appendix B). The national standard for ozone is not being met in most large centers of population, and the statutory deadline for attainment is December 31, 1987. Areas in nonattainment by that date will be required to submit plans for additional control of volatile organic compound emissions. Figure 1-1 shows the ozone nonattainment areas by county. In general, heavily populated areas fail to meet the standards. In attainment areas, new source review requirements being considered in some states may involve vapor emission controls for new terminals. Technology for controlling vapor emissions from marine cargo loading is available and in use for some cargoes. Vessels and marine terminals that load liquefied natural gas, acrylonitrile, and other hazardous fluids (and a few that load crude oil or gasoline in areas of strict air quality control) routinely capture and reuse or dispose of vapors emit- ted during cargo operations, piping the vapors to incinerators, flares, or recovery systems. Safety devices are employed to prevent or limit the effects of fires and explosions. Controlling vapor emissions from gasoline and crude oil loading would require extending this practice broadly. Processing flammable vapors could present an added hazard at barge and tankship terminals, and would entail substantial investments by the tank vessel and terminal industries. These prospects have raised concerns on grounds of both safety and economic impact. Regulations being considered in several states would require loading terminals to install and operate systems for piping hydrocarbon vapors to recovery or disposal equipment. Vessels, too, would be retrofitted. Installing and operating these systems could challenge the engineering, operational, and training standards of some sectors of the industry, especially at the lower technology end of the scale, such as inland barges and small product terminals. The drive to clean up the air in this instance raises a potential conflict of national interest between air quality, as regulated by the U.S. Environmental Protection Agency (EPA) and the states, and operational safety, the primary concern of industry and the U.S. Coast Guard. LAWS AND REGULATIONS CONCERNING AIR QUALITY AND MARITIME SAFETY The Clean Air Act and the States The federal Clean Air Act (CAA) of 1970, as amended, created the basis for a cooperative federal and state program to control air pollu- tion. Under the act, National Ambient Air Quality Standards (NAAQS) are established by the EPA for certain "criteria pollutants." For areas not

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10 in attainment of a standard, each state must develop and enforce a State Implementation Plan (SIP), with specific emissions limitations to meet the standard by statutory deadlines. Ozone in the lower atmosphere is one of the criteria pollutants, with a compliance deadline of December 31, 1987, and several states are now considering regulating sources of volatile organic compounds. VOCs, mainly hydrocarbon vapors, are precursors of ozone. Among the sources being considered for control are marine terminals serving tank barges and tankships. Marine vessels, unlike other mobile emission sources such as auto- mobiles, are not expressly regulated by federal air quality legisla- tion. The extent of EPA's power to regulate the emissions of so-called mobile sources indirectly, by attributing them to their stationary gathering points (in this case, marine terminals), is not explicitly defined. It is unclear whether EPA may require states to regulate indirectly marine vessel emissions. In the absence of explicit gui- dance, some states have determined that loading and ballasting emissions from vessels can be attributed to the adjacent shore facility. However, the CAA does not preclude states from doing so in a SIP. (Appendix C discusses the CAA and related legal and policy issues as they apply to the control of hydrocarbon vapor emissions from tankships and barges.) Under the pressure of the ozone deadlines, and the severe penalties for nonattainment, several states are considering this step. Coast Guard Authority in Marine Safety The U.S. Coast Guard, under the Port and Tanker Safety Act (PTSA) of 1978 (33 USC section 1221-31 and 46 USC chapter 37) and other statutes, has clear and comprehensive responsibility for marine safety and for preventing the pollution of water by vessels. Under this authority, the Coast Guard regulates the design, construction, repair, maintenance, operation, and manning of tank vessels. The Coast Guard, except to a limited degree, has no specific regula- tions in place to address the safety of vapor control devices on board tank vessels, although it does approve and inspect vapor recovery equip- ment under its general regulatory and inspection authority. The Coast Guard has general authority to review and approve the safety aspects of shoreside facilities at terminals. It may shut down terminals whose operations are identified as unsafe. Vapor control regulations might apply equally to both domestic and foreign vessels visiting a port in which controls are in force. There- fore, issues of national uniformity and deference to international regulation require careful consideration. ESTIMATING EMISSIONS To estimate emissions of VOC vapors from maritime sources, it is necessary to develop an understanding of the marine terminals and vessels that handle petroleum cargoes, and of the cargoes themselves.

11 Sources of Emissions When liquid cargo is loaded into a tank, some vaporizes into the tank atmosphere. As the tank is filled, the vapors are displaced and forced out of tank vents. The displaced gases contain the VOC vapors of the cargo being loaded and vapors from the previous cargo, if the tank was not purged of gas or "gas-freed" since the last time it was loaded. A cargo tank that has undergone crude oil washing (see Chapter 2) releases more vapors than a tank that has not. Figure 1-2 illustrates the emission of vapors while loading. ULLAGE HATCH~: VAPOR TO ATMOSPHERE _ PRESSURENACUUM l VALVE ,- _ ~I it_ IGS OR Vim HEADER ~- ~_ ~ CARGO LOADING HEADER - :; )~d ...' , , . 1 1 VAPORS · t.t-1.1.1...1.:1.1:1:I:t..l FIGURE 1-2 Emissions from cargo loading. Vapor emissions from tankship ballasting are also of some concern, although diminishing in importance. After unloading, many tankships travel without cargo. For stability, they must carry water as ballast. When ballast water is loaded into cargo tanks full of vapor from the preceding cargo, the vapor is displaced and emitted in much the same way as in loading cargo. Most tankships built since 1980 are required by domestic law and international agreement to use segregated ballast tanks and thus do not emit vapors during ballasting. Older and smaller tank- ships remain unaffected by the requirement. Inland barges do not carry ballast. VOC vapors are also released by tank "breathing," the result of pressure changes in the cargo tank owing to changes in temperature. These emissions are small, and they occur mainly away from ports while vessels are underway, or, in the case of barges, while they are fleeted. Small vapor emissions also occur during cargo gauging, when a hatch cover is opened to permit inspectors to measure the cargo; no attempt was made to calculate this small amount of emissions. - Emissions from unloading are not addressed in this report because emissions from unloading tank vessels are released, if at all, on shore. These emissions are subject to state regulation and licensing.

12 TABLE 1-1 EPA Emission Factors in Pounds Per 1,000 Gallons of Liquid Loading Operations Emission Source Ships Barges Tanker Ballasting Gasoline 1.8 3.4 0.8 Crude oil 0.61 1.0 1.2 JP-4 0.5 1.2 Unknown Kerosene 0.005 0.013 Unknown Distillate oil no. 2 0.005 0.012 Unknown Residual oil no. 6 0.00004 0.00009 Unknown Source: U.S. Environmental Protection Agency (1985~. Facilities that clean cargo tanks are also sources of vapor emissions. These facilities are outside the scope of this study. Emission Factors Emissions of VOCs are estimated by multiplying the amount of liquid cargo loaded by an emission factor, generally expressed in pounds per 1,000 gallons of liquid. Emission factors have been developed for many organic compounds. Table 1-1 summarizes typical emission factors devel- oped by the U.S. Environmental Protection Agency (1985) and given in the agency's AP-42 publication. Table 1-2 lists additional emission factors from Scott Environmental Technology, Inc. (1981~. The difference in emission factors between tankships and tank barges is due to differences in tank configuration. Tankship tanks are deeper and have less surface area; consequently less cargo is evaporated. Vessel Population Tank vessels include both tankships, which are self-propelled, and tank barges, which are not. Aside from some oceangoing barges and a few oceangoing integrated tug-barge combinations, the tank barges generally ply the inland waterways of the United States. The tankships other than for petroleum importation are used mainly in coastal traffic, since almost no petroleum is exported. Tankships in active trade in and with the United States range in size from less than 1,000 deadweight tons (dwt) to 406,000 cwt. Data on tankships holding active U.S. Coast Guard certificates of inspection or compliance (necessary documents for entry into U.S. ports) at the end of 1986 show 152 U.S.-flag tankships of more than 20,000 dwt trading in U.S. waters (9.4 million dwt) as well as 990 foreign-flag tankships of more than 20,000 dwt (77.3 million dwt). In 1986 there were only 81

13 TABLE 1- 2 Scott Environmental Technology Emission Factors in Pounds Per 1, 000 Gallons of Liquid Product Benzene JP -4 JP-5 Kerosene Mixed chemicals Lube oil Naphtha Distillate oil Loading/Ballast Emissions 1.0 0.6 0.005 O.005 0.005 0.005 0.3 0.3 0.005 Source: Scott Environmental Technology (19811. U.S.-flag tankships of less than 20,000 dwt, whose total tonnage of 240,000 dwt reflects the very small size of many of these vessels. In 1986, 3,968 barges in the United States were certificated to carry subchapter D cargoes (generally flammable liquids , including crude oil and gasoline) or both subchapter D cargoe* and subchapter O cargoes (chemicals with hazards beyond flammability). Inla*d barges gener- ally range in size from 10, 000-40, 000 barrels (bbl). U.S. and international regulations require most tanksh~ps to have segregated or clean ballast tanks. (The amount of ballasting emissions depends on the amount of ballasting in uncleaned cargo-tanks.) They require most ships to have inert gas systems to charge the atmosphere above the cargo with a nonreactive gas as a safety measure. The gas piping of inert gas systems can be used as a vapor header, through which cargo vapors could be piped to vapor recovery or disposal units. It can also be used in transferring vapors from tank to tank during ballasting, thus limiting emissions (see Chapter 21. Figure 1-3 is a diagram of the international regulatory requirements. U.S. regulations incorporate and implement international regula- tions, and, because of a U.S. statutory provision, are somewhat more stringent in their requirements for existing product tankships of * The terminology refers to the subchapters of Title 46, Code of Federal Regulations (CFR), under which liquid cargo is regulated when carried in bulk on a vessel. Subchapter D is found in 46 CFR parts 30-38, and subchapter O is in 46 CFR parts 150-154. Subchapter D covers roughly 400 liquid and liquefied gas cargoes having only the hazard of simple flammability. Subchapter O covers approximately 300 liquid and liqu*fied gas cargoes having hazards beyond simple flammability. Approximately seven barrels are equivalent to one cwt.

1979 1980 1981 1982 1983 . 1984 1985 1986 New Tankers Existing Tankers SOLAS/Safety-IGS Requirements F.xl~tlng crawl (-() I~ci`~-t Feinting, ~ retain ~r`,tiu~ t - 4()-, () kJ`` t [:`l~ting cretin rebut t , () ~ l~ti`vt _ ~t MARPOL/ Pollution, CBT, SBT, COW Requirements [:xlsting crud`. 4~)-, (l kill`` t :xl~ting t~rocluct 4() - k~iv~t .. an. ~ ..~... . invites IMO to develop proposals tor appropriate am menci men ts to the MARl'OL Protocol flag once Inert state requirement US/UK O IMO O 611183>. !IIY ~ ~e ~::~::~ .. .~: ~ A '' . ' . . ' ' 61V83 BY ~ ~id, ~ ~85 :~: :: I: ;~ ~ ~ elm ,:,. ,, . _ . 611/81 t .. 9. ~.,,,,, ' 5~3 ~ ' ~ ~'~ ~ ~ ~ ~ i: _ ~ ~ . ' , . 6Q183.'. ~ '':~e '~56** `rt.lilidUminl~trdtioll~(~' ~ ~ 1~ K |.~.ll~h.lv( ~'n.)`t`.ltt`~` rcquir~ll,~nt~ h..l~l l t the` l!`l() rt alter. m. nt ~1.1t. ~ I'll rots r tl, then` In~ll\-l~ltl.ll ~ldnill1l` tr.ltl'.n~ tt.r ,tlr,ht r at tally ~IMO O ]~)J2fl983 {::8If :: 10/2/1981 SBT or COW SBT or COW lOf2''l983 ~10/2~1985 SBT Or COW SBT or COW . I()f'2fl^3 CBT or SOT . ~C,5 I always r uired ·~h~n C OW i!; Alps ratted ·~l~ the at H(V\'N1 near hi ~-emptecl It Installation In unrta ~ noble and Impractical · 'Requirecl only ll tittec] health TIC cowl stin'2 crucJe (,r F,r( duct tanker ()`er 7() 1~1^t tor `` huh th. . ret r \`dS ~,ldcec] att'r lo 31, ~ . r the deal 1.ll.1 att. r h A) ,h `,r clell`cred alter 12 ~l, ~ must h biro\ lded ~ 1th bBl In a-ran.. with Regulation 1 l ( 1, SlARI'( ll l'roto<-ol 1978 t lapa n en t`,rce~i tht same requ lrements n l Ilil8; t tO'I discharge monitoring and cat ntrol ss stem requ lred late 14t\~ FIGURE 1-3 Tanker safety and pollution prevention design requirements. Source: Exxon Marine, 1987. LEGEND: SBT (segregated ballast tank). When a tanker discharges its cargo, it must take on ballast water to maintain a seaworthy condition. Under present regulations, ships take water into empty cargo tanks. Before the ship reloads, the ballast water is discharged either into shore reception facilities or as clean ballast after a load on top (LOT) operation. SBT requires sufficient tanks for carrying only ballast water so that under ordinary circumstances ballast water does not enter the cargo tanks. As the chart shows, this measure was adopted for newbuildings. PL (protective location). With the PL concept, SBTs are placed in selected areas of the vessel where it is believed they can provide a

15 degree of optimum protection for the ship's crew and cargo in the event of a grounding or collision. CBT (clean ballast tank). In existing ships, CBTs are cargo tanks dedicated to carrying ballast. As the chart shows, this option was available for existing tankers only during the specified interim, until the SBT became mandatory. Although similar in concept to SBTs, CBTs do not require separate pipes and pumps for taking on and discharging ballast. COW (crude oil washing). COW is the cleaning of cargo tanks with high-pressure jets of crude oil while the ship is discharging. The crude oil pumped through the ship's tank washing machines acts as a cleaning agent and removes oil residues, which are then pumped ashore with the cargo. COW requires the installation of fixed-in-place washing machines and IGS. HCWM (high-capacity washing machine). HCWM is a tank-cleaning machine with a capacity of 60 cubic meters per hour or more. IGS (inert gas system). IGS permits a ship to maintain an inert, that is, nonflammable, atmosphere in cargo tanks. In a typical system, boiler flue gas is cleaned, cooled, and pumped to tanks. Although hydro- carbon vapors might also be present in the tanks, oxygen levels in the inert gas are too low to support combustion. LOT (load on top). LOT is a system based on the principle that when oil and water mixtures are left standing, the oil separates and rises to the top. The heavier clean water at the bottom can be drawn off and returned to the sea; oil and water mixtures that remain are transferred to a slop tank. After a period of time, the mixtures separate further, and clean water can again be removed from the bottom of the tank. At the next loading port, new cargo is loaded on top of the reclaimed oil in these tanks. LOT, in use for many years, has contributed signifi- cantly to the reduction of operational pollution from tankers. 20,000-40,000 cwt. Domestic product tankships of this size range, and foreign product tankships visiting the United States, must have segre- gated or clean ballast tanks by January 1, 1986, or by the date on which the vessel is 15 years old, whichever is later. Figures 1-4 and 1-5 show the numbers of vessels affected by these domestic and international regulations. Trade The committee estimated the volumes of relevant liquid cargoes loaded in U.S. ports to determine which cargoes make the most important contributions to vapor emissions. Tables 1-3, 1-4, and 1-5 summarize data from the U.S. Army Corps of Engineers on the 1984 transport of crude oil, oil products, and chemicals in the United States. Most U.S. harbors are too shallow to admit large tankships. At these harbors, large ships must remain outside and off-load to a series

16 40 ~n LL cn 3 1 cn LU ~ 20 o c: m 10 z 40 ~n , 30 ~n LL o cr: LL m z 20 10 o cn 4o cn ~n o ~: m z 30 20 10 Crude Oil SBT or COW SBT or SBT or COW COW Under 15 yre old Over 15 yrs old SBT SBT [, , .. .... . . ~ 20-40 40-70 Over 70 20-40 MDWT MDWT MDWr 40-70 Over 70 MDWT NlDWT MDWT Existing New, from 1979-1982 SBT or _SBTor CBT CBT at 1 5yrs ~ - SBT or SBT or ~ther other at .. Over 20 MDWT New, after 1982 Product SBT or CBT at SBT or t5 yrs CBT 1 t~s~: ::.::. ::::.-:-:':.: :,.: :;.:;.:. :-:;.:. .-:.-:.1 20-40 40-70 Over 70 MDWT MDWT MDWT Under 15 yrs old Over 15 yrs old SBT 20-40 40-70 Over70 Over30 MDWT MDWr MDWI MDWr Existing New, from 1978-1982 Oil/Product SBT or SBT or OthQr SBT or other ~ other at SBT or other 20-40 40-70 Over 70 MDW1 MDWT MDWT 20-40 40-70 Over70 MDWT MDWT MDWT Existing New, from 1978-1982 New, after 1982 Under 15 yrs old Over 15 yrs old SBT Over 20 MDWT New, after 1982 FIGURE 1-4 U.S.-flag tankships in compliance with U.S. safety and pollution-prevention requirements. Source: Based on U.S. Coast Guard data.

1 7 400 300 U) LL o m z 200 100 100 cn LL CO 75 LIJ o C[: LIJ m z 50 25 o 100 J LL O) 75 cn LL o ~: LIJ m z 50 25 O SBT or COW SBT or SBT ~COW at or SBT or 15 yrs COW COW SBT or CBT at 15yrs .~.~..~ SBTor CBT Crude Oil SBT or SBT or SBT Under t5 yrs old Over 15 yrs old 20-40 40-70 Over70 20-40 40-70 Over70 Over20 MDWT MDWT MDWr MDWT MDWT MDWT MDWT Existing New, from 1980-1982 New, after 1982 Product SBT or CBT at 1 5 yrs SBT or SBT o' CBT CBT SBT or CBT _ ~ ~ ~; ~,, t ~ Under 15 yrs old 20-40 40-70 Over70 20-40 40-70 Over70 Over 30 MDWT MDWT MDWT MDWr MDWr MDWT MDWT Existing New, from 1980-1982 New, after 1982 SBT or other at 15 yrs S2BhT or Oil/Product ~; ........ . . SBT or SBT or .. other other Under 15 yrs old Over t5 yrs old SBT SBT or other at SBT or 1~; vre other 20-40 40-70 Over70 20-40 40-70 Over70 Over30 MDWT MDWT MDWT MDWT MDWT MDWT MDWT Existing New, from 1980-1982 New, after 1982 *Note Scale Change FIGURE 1-5 Foreign-flag tankships (trading at U.S. ports) in compliance with safety and pollution-prevention requirements. Source: Based on U.S. Coast Guard data.

18 TABLE 1-3 1984 Summary of Trade in Millions of Short Tons Other Organic Petroleum Type of Trade Crude Oil Gasoline Chemicals Products Foreign Import171.64 12.55 19.68 68.37 Export0.02 0.44 13.15 17.53 Subtotal171.66 12.99 32.83 85.90 Domestic Ship135.00 17.40 3.86 43.57 Barge45.80 59.61 29.64 139.11 Subtotal180.80 77.01 33.50 182.68 Total352.46 90.00 66.33 268.58 TABLE 1-4 1984 Organic Chemicals Trade in Millions of Short Tons Crude Tar, Type of Oil, Gas Trade Products Alcohols Benzene and Basic Miscellaneous Toluene Chemicals Chemicals F. orelgn Import 0.406 1.036 0.802 16.20 1.24 Export 0.436 0.913 0.173 10.69 0.94 Subtotal 0.84 1.95 0.98 26.89 2.18 Domestic Ship 0.12 0.48 0.53 2.51 0.23 Barge 1.17 3.81 3.69 20.44 0.53 Subtotal 1.29 4.29 4.22 22.95 0.76 Total 2.13 6.24 5.20 49.84 2.94 Source for Tables 1-3 and 1-4: U.S. government data obtained from the Maritime Administration. of smaller vessels, in a process known as lightening. Approximately 60 million tons of cargo is lightered at U.S. ports annually. Most lighter- ing is done from more than 30 miles offshore, so that emissions from these operations are well dispersed before reaching land. About 20 million tons of cargo, mainly crude oil, were lightered nearer to shore in 1985.

19 TABLE 1-5 1984 Other Petroleum Products in Millions of Short Tons Type of Jet Trade Fuel Kerosene Fuel Oil Distillate Residual Lube Naphtha and Fuel Oil Oil Solvents Foreign Import 2.12 0.28 14.68 40.86 1.20 9.23 Export 0.39 - 3.14 12.22 1.65 0.13 Subtotal 2.51 0.28 17.82 53.08 2.85 9.36 Domestic Ship 4.63 0.60 14.71 20.34 2.18 1.11 Barge 9.11 1.69 45.81 74.89 3.02 4.59 Subtotal 13.74 2.29 60.52 95.23 5.20 5.70 Total 16.25 2.57 78.34 148.31 8.05 15.06 Lion. Source: U.S. government data obtained from the Maritime Administra In total, tank vessel loadings of crude oil and gasoline are declin- ing, as pipelines exploit their cost advantages and as oil consumption has remained stable. Figure 1-6 illustrates this trend. Emissions Calculations The committee calculated VOC vapor emissions on a national basis, using methods derived from a study by the EPA (1986), but with more detailed information on vessel characteristics. Table 1-6 summarizes the committee's estimates of VOC emissions from vessel loading and ballasting. Appendix D presents the details of the calculations. Vessel loading emissions are calculated using the quantity of cargo loaded (in tons), the emission factor f, and the density of the cargo (tons per 1,000 gallons). Emissions are calculated by the follow- ing equation: E = (C/d~f, where E = mass of emissions; c = mass of cargo; d = density of cargo (mass per unit volume); and f = cargo-specific emission factor (mass per unit volume). Lightering emissions are calculated by the same formula. Ballasting emissions are calculated from the quantity of cargo off- loaded (in tons), the density of the cargo, the percentage of ballast loaded, the fraction of ships using cargo tanks for ballast, and an emission factor. The committee's calculations assume that, in port, tankships ballast up to 30 percent of their deadweight. U.S. regula

20 1400 1200 1000 800 600 400 200 o Plpellne Tank Vessel 1973 1975 1977 1979 YEAR 1981 1983 1985 FIGURE 1-6 Comparison of tank vessel and pipeline flows--Gulf to Atlantic regions, 1973-1985. Source: U.S. Department of Energy data. Cited in Booz-Allen & Hamilton, Inc., 1987. tions forbid vessels with segregated or clean ballast tanks to ballast into uncleaned cargo tanks, except in emergencies. They also require vessels with crude oil washing systems to provide a method to prevent VOC emissions during ballasting of cargo tanks. The ballasting emis- sions estimates in Table 1-6 account for the 30 percent assumption. The formula for estimating ballasting emissions is as follows: E = (c/d~x x O .30 x f, where E = mass of emissions; c = mass of cargo; d = density of cargo (mass per unit volume); x = percentage of tankships without equipment to prevent ballasting emissions; and f = cargo-specific emission factor (mass per unit volume). Locations of Emissions More than 98 percent of vapor emissions occur at the port of load- ing. If that port is in a nonattainment area for ozone, the state government may be particularly concerned about vessel emissions.

21 TABLE 1-6 Estimated Annual Emissions in Metric Tons, 1984 Organica Activity Crude Oil Gasoline Chemicals Other Petroleum Totale Foreign Loadingb--1136332208 Ballasting413109914544 Lightering2,503------2,503 Domestic Ship loadingb10,3174,5447740415,342 Barge loadings5,73729,4155621,909-37,623 Ballasting259127523414 Totalse19,22934,3087172,38156,635 aOrganic chemicals include alcohols, benzene and toluene, crude tar, oil and gas products, basic chemicals, and miscellaneous chemi- cals. While not all the basic chemicals are organic, because there was no method of separating trade data for organic and inorganic basic chemi- cals, all basic chemicals for the purpose of the emissions calculations were assumed to be organic. Emissions from organic chemicals are calcu- lated using the Scott emission factor (Table 1-2) of 0.005 pounds per 1,000 gallons for mixed chemicals. These assumptions result in higher emls s Ions . bShip-loading emission calculations assume that cargo tanks are not gas freed. On specialized chemical tankers, the tanks are usually gas freed. These assumptions lead to higher emissions estimates. CBecause data on ocean barges are aggregated with those on inland barges, it was necessary to use identical emission factors for the two classes of vessels. This simplification results in a small overestimate of emissions since ocean barges are much like tankships in their opera- tion and construction (aside from the lack of propulsion), and lower emission factors apply to tankships. dAn assumption here is that all jet fuel transported is JP-4. Since other grades of jet fuel have lower emissions factors, this assumption leads to a high estimate. eTotals may not add because of rounding. Source: Appendix D. The estimates in Table 1-6 show that more than 95 percent of all VOC emissions from vessels are from crude oil and gasoline. With this fact in mind, the committee focused its attention on these two liquids.

22 Loading Ports for Domestic Oil and Gasoline Tables 1-7 and 1-8 list loading volumes of crude oil and gasoline, respectively, at U.S. ports loading more than 100,000 tons per year for domestic shipping. These ports account for more than 98 percent of crude loadings and 95 percent of gasoline loadings in domestic trade. The tables also give the ports' ozone attainment status. Tables 1-9 and 1-10 summarize the data by state. As the tables show, the only states where ports in nonattainment for ozone load more than 5 million tons of crude oil and gasoline annually are Texas, New York, Louisiana, and California. Loading Ports for Crude Oil and Gasoline Exports Table 1-11 is a list of all U.S. ports that export gasoline. None is in attainment of the ozone standard. Almost no crude oil is exported from the United States. Table 1-12 lists all U.S. ports loading more than 1 million short tons of crude oil or gasoline, with their ozone attainment status. Exports of gasoline and crude oil are less than 1 percent of the total loadings for domestic movement of these cargoes. FOCUS FOR ASSESSMENT The foregoing estimates show that 95 percent of the VOCs emitted from marine cargo handling are associated with loading crude oil and gasoline at marine terminals. Accordingly, the committee focused on those cargoes and operations.

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29 TABLE 1-9 Domestic 1985 Crude Oil Movements by State with 1985 Ozone Nonattainment Status of Loading Ports Handling More Than 100,000 Short Tons Percentage of Loadings State Nonattainment Attainment Total Short Tons Areasa Areas (thousands) Alabama 9372, 489 Alaska 100101,237 California 594112,795 Delaware 1008,155 Florida 100 659 Illinois 100 809 Louisiana 326821,845 New Jersey 100 197 New York 100 961 Ohio 100 743 Puerto Rico 100483 Texas 49517,048 Virgin Islands 100283 Total 157,704 aLoadings in nonattainment areas are about 23.5 percent of total.

30 TABLE 1-10 Domestic 1985 Gasoline Movements by State with 1985 Ozone Nonattainment Status of Loading Ports Handling More Than 100,000 Short Tons Percentage of Loadings State Nonattainment Attainment Total Short Tons Areas Areas (thousands) Arkansas 100304 California9192,082 Connecticut100 40 Delaware100 1,315 Hawaii 100196 Illinois68321,421 Indiana55451,109 Louisiana9379,297 Massachusetts100 318 Minnesota 100785 Mississippi 1002,784 Missouri100 13 New Jersey100 1,557 New York99123,117 Ohio100 624 Oregon100 489 Pennsylvania29712,458 Puerto Rico 100614 Tennessee100 317 Texas100 17,175 Virginia 1001,268 Virgin Islands 1001,336 Washington59S4,881 Total 73,989 aLoadings in nonattainment areas are 78.8 percent of total.

31 TABLE 1-11 Gasoline Exports by Porta Gasoline Gasoline Exports Exports Port (tons) Port (tons) California Michigan Long Beach8,957 Detroit82 Los Angeles69 Saginaw186 Suisun Bay33,608 Total268 San Francisco41 San Pablo6,315 New Jersey Carquinez48,796 Camden150 Strait Total150 Oakland255 Total98,091 New York Albany45 Florida New York23,521 Port Everglades1,394 Total23,566 Palm Beach225 Miami227 Pennsylvania Total1,846 Philadelphia173 Total173 Louisiana New Orleans7,321 Puerto Rico Lake Charles254 San Juan10,298 Total7,575 Total10,298 Maryland Texas Baltimore1,220 Texas City462 Total1,220 Houston137,124 Corpus Christi70,362 Massachusetts Port Arthur17,682 Boston8,998 Freeport14,650 Total8,998 Total240,280 aNational total for gasoline exports is 392,455 tons Source: U.S. Army Corps of Engineers data for 1985 .

TABLE 1-12 Ports Loading More Than 1 Million Tons of Crude Oil and Gasoline Annually, 1985 1985 Ozone Loadings Attainment (thousands of Port Statusa tons) Alabama Mobile N 2,318 Alaska Valdez A 99,625 Kenai A 1,177 Delaware Lower Delaware Bay A 8,155 California San Francisco N 3,949 Carquinez Strait N 1,300 Morro Bay A 4,270 Santa Barbara Channel Islands N 2,048 Suisun Bay N 1,100 Illinois Madison County N 1,777 Louisiana Baton Rouge Cameron Parish Destrehan Lake Charles New Orleans Ostrica Plaquemine Parish Red and Atchafalaya Rivers A Terrebonne Parish Vermillion Parish N A N N N A A A A Mississippi Pascagoula A New York Upper Bay N New York N New York and New Jersey Channels N 3,158 2,926 1,964 2,952 1,383 3,130 2,006 1,194 2,011 1,312 2,784 2,276 13,434 7,949 Pennsylvania Marcus Hook A 1,747 Texas Beaumont N N N N N Corpus Christi Houston Channel Houston Texas City Port Isabel and vicinity A Virgin Islands Chris tians ted A 2,900 7,428 3,206 2,137 2,870 3,125 1,620 aN = area in nonattainment for ozone; A - area in attainment.

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