Marine Security of Hazardous Chemical Cargo
Released: 2005-08-26T00:00:00

Introduction

The federal government has statutory obligations to regulate interstate commerce and securethe United States against terrorism. Therefore, Congress has a strong interest in federal regulationsand programs related to hazardous chemicals security. Since September 11, 2001, legislators,government agencies, and industry have been working to prevent terrorist attacks involvinghazardous chemicals. Their goal is to ensure the continued availability of such chemicals forcommercial use while reducing the risk of their exploitation by terrorists.

Large quantities of hazardous chemicals are found in commercial facilities, marinetransportation, rail transportation, and highway trucking. (1) To date, Congressional attention has focused largely on the securityof hazardous chemicals transported by rail or tanker trucks, or stored at commercial facilities nearpopulated areas. As the nation's rail, truck, and chemical facility policies mature, Congress isreviewing federal policies related to marine transportation of hazardous chemical cargo. (2) In the 109th Congress, forexample, H.R. 2651 would establish or increase penalties for criminal or terrorist activities aroundports and marine vessels. S. 1052 includes provisions to increase general port security, includingports in foreign countries. In response to the overall security environment, Congress is likely to seeka broader understanding of hazardous chemical marine shipments and efforts to secure them.

This report provides an overview of hazardous chemicals marine transportation in the UnitedStates. The report discusses the general risks from such marine transportation in the homelandsecurity context. It focuses on many of the hazardous chemicals with the greatest potential to affectthe public in a terrorist attack and the marine vessels that carry such chemicals. It summarizesfederal statistics on the hazardous chemical marine shipments in U.S. waters, including shipmentvolumes by type of chemical and port location. It provides a brief overview of relevant U.S.maritime security regulation. It raises security policy issues associated with these shipments,including risk uncertainties, security resources, and security effectiveness. The report concludes witha discussion of marine chemicals security as part of the nation's overall chemical security strategy.

Scope and Limitations

This report addresses marine shipments of a limited set of acutely hazardous chemicalcargoes that, if released, could potentially pose a catastrophic hazard to the general public. (Thespecific cargoes are defined in subsequent sections). The report does not examine other potentialmaritime security hazards such as petroleum products, biological agents, or container bombs, whichmay also be of interest to policymakers. (3) It focuses on threats to the general public from chemical releaseduring marine transport. It does not address marine attacks targeting economic activity or theenvironment. Due to the sensitive nature of the topic and legal limitations on the publication ofcertain proprietary shipping data, the report does not provide detailed statistics for the specifichazardous chemicals or ports of interest.

Maritime Terrorism and Hazardous Chemical Cargo

Marine shipments of hazardous chemical cargo are potentially attractive terrorist targetsbecause these chemicals are acutely toxic or highly combustible, and are shipped in large volumes. They may represent a serious threat to human life and physical infrastructure if intentionally releasednear populated areas. Hazardous chemical marine vessels are also part of two "criticalinfrastructures" identified by the Bush Administration--the chemicals and transportationsectors. (4) For thesereasons, the protection of hazardous chemical shipments passing through U.S. waterways and portsis an important component of U.S. homeland security strategy.

Although security experts widely acknowledge that marine shipments of hazardous chemicalsmay be attractive terrorist targets, no marine vessel carrying hazardous chemicals has been used byterrorists in an attack on civilians. Nonetheless, marine accidents involving such shipments in theU.S. and abroad have demonstrated their potential to impact nearby communities. Foreign terroristsalso have successfully attacked other types of marine vessels overseas. As discussed later in thereport, intelligence suggests that terrorists may have both the interest and capability to executehazardous chemical shipping attacks in the United States.

Hazardous Marine Cargo Accidents

Major accidents involving the marine transportation of hazardous chemicals are uncommon. (5) However,those that have occurred include some of the deadliest industrial accidents ever recorded. In 1917,for example, the explosion of the Mont-Blanc, carrying a cargo of explosives in the port of Halifax,killed over 1,900 people and seriously injured over 4,000 others. (6) The 1947 explosion of twocargo ships carrying ammonium nitrate and sulfur in Texas City, Texas destroyed the port, killingnearly 600 people and injuring another 3,500. (7)

Due to improved safety practices and vessel construction, a marine accident as destructiveas the Texas City disaster has not occurred in the ensuing 60 years. However, serious incidentsinvolving chemical marine shipments have forced the evacuation of threatened coastal populations. These incidents include a 1985 fire aboard the Ariadne carrying 100 containers of toxic chemicalsin the port of Mogadishu, Somalia (8) ; a 1987 accident aboard the Cason carrying 1,200 tons offlammable, toxic, and corrosive chemicals near Cape Finisterre, Spain (9) ; and a 1999 fire aboard the Multitank Ascania carrying a cargo of vinyl acetate off the coast of Scotland. (10) These incidents did notresult in serious casualties among neighboring communities, but emergency responders had a highdegree of concern for public safety as indicated by the associated evacuations.

Likelihood of Terrorist Attacks on Ships

Although terrorists have never used a marine cargo vessel to launch a chemical attack on thegeneral public, both international combatants and domestic terrorists tried to use explosives torelease chemicals from land based manufacturing and storage facilities during the 1990s. Most ofthese attempts were in foreign war zones such as Croatia. They included attacks on a plantproducing fertilizer, carbon black, and light fraction petroleum products; other plants producingpesticides; and a pharmaceutical factory using ammonia, chlorine, and other hazardous chemicals.All of these facilities were close to population centers. In the United States, there were at least twoinstances during the late 1990s when criminals attempted to release chemicals from similar facilities.One incident involved a large propane storage facility in California, and the other a gas refinery inTexas. (11)

Terrorists have directly targeted marine vessels, mainly to destroy the vessel or cargo. InJune 2002, Moroccan authorities foiled an Al-Qaeda plot to attack U.S. and British warships, andpossibly commercial vessels, in the Straits of Gibraltar. (12) In October 2002, the oil tanker Limburg was successfullyattacked off the Yemeni coast by a bomb-laden fishing boat. (13) Foreign governmentshave reportedly expressed concerns about terrorist groups commandeering a hazardous chemicalvessel and "crashing it into a port." (14)

In the United States, the Department of Homeland Security (DHS) has been consistentlyconcerned about the security of chemicals infrastructure, including chemical tanker ships. (15) The Homeland SecurityCouncil included terrorist attacks on ships carrying flammable and toxic chemical cargoes in a U.S.port among the hazard scenarios it developed as the basis for U.S. homeland security nationalpreparedness standards. (16) The President's National Strategy states that "much of the portsystem represents a significant protection challenge, particularly in the case of high consequencecargo." (17)

One type of hazardous marine cargo--liquefied natural gas (LNG)--has received particularpublic attention. The DHS reportedly included LNG tankers among a list of potential terrorist targetsin a security alert late in 2003. (18) The DHS also stated that "the risks associated with LNGshipments are real, and they can never be entirely eliminated." (19) A 2004 report by SandiaNational Laboratories considered potential terrorist attacks on LNG tankers "credible andpossible." (20) TheSandia report identified LNG tankers as vulnerable to ramming, pre-placed explosives, insidertakeover, hijacking, or external terrorist actions (such as a Limburg -type attack, a missile attack, oran airplane attack). (21)

What is "Hazardous" Chemical Cargo?

Homeland Security Presidential Directive 7 (HSPD-7) directs federal homeland securityactivities to focus on terrorist attacks that could cause "catastrophic health effects or mass casualtiescomparable to those from the use of a weapon of mass destruction." (22) For purposes of thisreport, hazardous chemical cargo is chemicals carried aboard a commercial marine vessel that, ifaccidentally released or combusted, could, under certain circumstances, pose a catastrophic hazardto the general public. Typically, such hazards could include poisoning, asphyxiation, chemicalburns, or thermal burns. In some cases, a single chemical could present a combination of thesehazards. Numerous federal standards identify potentially hazardous chemicals. With respect topublic security, relevant standards are promulgated by the Department of Transportation (DOT), theCoast Guard, and the Environmental Protection Agency (EPA).

DOT Hazardous Materials

The DOT regulates the transportation of all hazardous materials under the HazardousMaterials Transportation Act of 1975 ( P.L. 93-633 ) and subsequent amendments. The act empowersthe Secretary of Transportation to designate as "hazardous" any particular quantity or form ofmaterial that "may pose an unreasonable risk to health, safety and property when transported incommerce." The DOT defines and classifies hazardous materials in 49 C.F.R. Â§ 172.101. TheDOT's list includes thousands of materials--including toxic, radioactive, corrosive, explosive, andflammable materials--which could potentially be shipped. The DOT groups individual materials bytype of hazard (e.g., inhalation poisoning) but not necessarily by relative degree of hazard. The DOTdoes provide a ranking of relative hazard by general class or division in 49 C.F.R. Â§ 173.2a. Thisranking is summarized in Appendix 1 .

In addition to its general hazardous material safety regulations, the DOT requires shippersof certain "highly hazardous" cargo to develop security plans in 49 C.F.R. Â§ 172.8. (23) Under these provisions(subject to various conditions), the DOT defines highly hazardous cargo to include:

radioactive material (Class 7);

over 55 pounds of explosives (Division 1.1, 1.2, or 1.3);

over 1.06 quarts per package of material poisonous byinhalation;

3,500 gallons or more of bulk hazardous liquids orgases;

468 cubic feet or more of bulk hazardous solids;

5,000 pounds or more of packaged hazardous material;

agents regulated by the Centers for Disease Control and Prevention;

certain hazardous materials that require placarding under other provisions in49 C.F.R. Â§ 172.

Note that the DOT's definition of "highly hazardous" materials extends to most of the materials in49 C.F.R. Â§ 172.101 when they are present above the prescribed quantities.

Coast Guard Hazardous Cargoes

The Coast Guard regulates the safety and security of marine vessels and is responsible forenforcing all applicable federal hazardous material laws in U.S. waters. Coast Guard regulationsidentify hazardous cargo in several sections of the federal code. Under the Port and WaterwaysSafety Act of 1972 (P.L. 92-340), the Coast Guard defines "certain dangerous cargoes" in 33 C.F.R.Â§ 160.204. The definition of "certain dangerous cargoes" refers to the DOT list mentioned above, and specifically names certain liquefied gas and bulk liquid cargoes. In 46 C.F.R., the Coast Guardprescribes special requirements for vessels carrying certain hazardous materials, identified asfollows:

Bulk solid hazardous materials (46 C.F.R. Â§ 148).

Bulk liquid hazardous materials carried in barges (46 C.F.R. Â§151).

Bulk liquid, liquified gas, or compressed gas hazardous materials carried byship (46 C.F.R. Â§ 153).

Incompatible chemicals where multiple chemicals may be carried together inparcel tankers or on container ships (46 C.F.R. Â§ 150).

The Coast Guard also identifies hazardous marine cargoes through regulation of waterfront facilitieshandling these cargoes in 33 C.F.R. Parts 126, 127, and 154. Collectively, hundreds of differenthazardous materials are included on the Coast Guard's lists. While Coast Guard regulations identifyparticular hazardous materials potentially carried in marine vessels, they do not necessarily identifythe relative degree of hazard among these materials.

EPA Hazardous Substances

The EPA regulates stationary facilities handling potentially hazardous substances under theClean Air Act (CAA), Section 112(r)(7). In 1990, Congress passed P.L. 101-549 , which amendedthe CAA, Section 112, to require facilities possessing more than specified threshold quantities ofcertain hazardous substances to file risk management plans (RMPs). These RMPs summarize thepotential threat from sudden, large releases of those substances. These plans must also include theresults of off-site consequence analysis for a worst-case accident and plans to prevent releases andmitigate any damage.

The Clean Air Act Amendments defined "hazardous substances" to include 14 listedsubstances (including chlorine and ammonia) and at least 100 additional chemicals to be designatedby the EPA. The amendments directed EPA to designate chemicals posing the greatest risks tohuman health or to the environment, based on three criteria: the severity of potential acute adversehealth effects, the likelihood of accidental releases, and the potential magnitude of human exposure. The EPA promulgated a list of 77 acutely toxic substances, 63 flammable gases and volatileflammable liquids, and "high explosive substances" (found in 40 C.F.R. Â§ 68). As a result of a legalsettlement, the EPA deleted high explosives from the list in 1998. The list was further amended in2000 to exclude flammable substances when used as a fuel, or held for sale as a fuel at a retailfacility. The current EPA/RMP list is shown in Appendix 2 . (24)

The vast majority of hazardous materials on the DOT lists do not likely represent a"catastrophic" health hazard to the general public, because the materials involved are not shippedor stored in sufficient quantity, or because their physical properties limit their potential off-siteimpacts. Likewise, most of the hazardous materials listed by the Coast Guard in 33 C.F.R. and 46C.F.R. do not represent catastrophic health hazards. Accordingly, the EPA list may moreappropriately identify those chemicals considered to have the greatest potential consequences to thegeneral public. Since the chemicals in EPA's list are considered among the most hazardous on land,it follows that many of them may be similarly hazardous if transported on water.

This report uses the EPA/RMP chemicals as the basis for marine cargo hazard analysis. Nearly all of the EPA's listed hazardous substances under the CAA Section 112(r) are found in theDOT and Coast Guard hazardous materials lists, so the findings in this report should be applicableto the DOT or Coast Guards lists as well. (The EPA/RMP chemicals are cross-referenced to theDOT categories in Appendix 2 .) Two notable classes of hazardous material identified by DOT noton the EPA/RMP list are radioactive materials and explosives. Army Corps of Engineers marinecommerce statistics for 2003 (discussed later in this report) show that explosives and radioactivematerials would account for less than 0.3% of U.S. hazardous marine cargo if added to theEPA/RMP hazardous materials list. (25) Excluding these two classes is unlikely to affect the policyconclusions in this report.

Health Effects of Hazardous Chemicals

As noted above, the EPA/RMP chemicals are broadly classified as acutely toxic or flammable(or both). The degree of toxicity or flammability of specific chemicals within the EPA/RMP listvaries with their chemical properties. The following example chemicals illustrate such variations:

Ammonia. Ammonia is an acutely toxic,potentially explosive, liquefied gas primarily used in the manufacture of fertilizers and as a fertilizeritself. It has many other uses as well; for example, as a chemical production component, as sourceof protein in livestock feeds, and in metal treatment operations. (26) Ammonia can reachharmful concentrations in the air very quickly on loss of containment. It can causing severe skinirritation, and if inhaled, can cause respiratory irritation, eye corrosion, and fatal fluid buildup in thelungs. (27)

Methane. Methane (natural gas) is used as aheating fuel and industrial feedstock for a range of chemical processes. Methane is not inherentlytoxic, although high vapor concentrations may cause asphyxiation by displacing breathable air. Cryogenic methane (liquefied natural gas, or LNG) may freeze body parts with which it comes intocontact. Methane is extremely flammable when mixed with air and may be explosive when suchmixtures are in confined spaces. (28)

Methyloxirane. Methyloxirane is used tomanufacture polyurethane foam (for furniture and cars), solvents (in paints, cleaners, and waxes),polyster resins, and other industrial products. Methyloxirane is a toxic liquid and a fire hazard.Human exposure may irritate the eyes, skin, and respiratory tract. Methyloxirane vapor is extremelyflammable when mixed with air and reacts explosively with chlorine, ammonia, strong oxidants, andacids. (29)

As the examples above demonstrate, an uncontrolled release of a specific chemical on theEPA/RMP list could have varying effects on an exposed population. Evaluating the particulareffects of such releases material by material is beyond the scope of this report, nor is it necessary fora general discussion of hazardous marine cargo policy. The important point is that the EPAconsiders all the RMP chemicals, when present above their individual threshold quantities, to besufficiently hazardous to the general public to warrant special regulatory treatment (i.e., off-siteconsequence analysis). Recognizing that certain shipments of specific cargoes may be morehazardous than others, this report assume that they are all hazardous enough to warrant publicconcern as potential terrorist targets.

Hazardous Chemical Releases Over Water

The EPA/RMP list of hazardous chemicals was developed for facilities on land. Due to theirchemical properties, the health hazard associated with these chemicals may be significantly differentif released over water. Certain EPA/RMP chemicals dissolve in water (e.g, propylene oxide) or sinkin water (e.g., tetramethyllead), potentially reducing the hazard they pose to the general public in amarine incident. Other chemicals (e.g., ammonia) dissolve in water, but evaporate quickly as well. Still others (e.g., cryogenic methane) float and evaporate faster on water than on land, creating alarger hazard zone more quickly in a marine release than a land release for the same quantity ofchemical. (30) Becauseland release and water release characteristics of specific EPA/RMP chemicals may differ, onlylimited conclusions may be drawn from a study of EPA/RMP hazards in marine shipments. Furtherresearch and analysis are required for a better understanding of the relative marine hazards ofspecific chemicals.

Hazardous Marine Cargo Statistics

The Army Corps of Engineers (ACE) maintains statistics of marine commerce in U.S. waters. These statistics may be used to estimate the marine shipping volumes of EPA/RMP chemicals. (See Appendix 3 for a description of the ACE database and its limitations.) According to the ACEstatistics, a subset of the EPA/RMP chemicals are transported through U.S. waters in significantquantities. Table 1 summarizes the total U.S. waterborne shipments of these chemicals by theDOT's general hazard category. As the table shows, over 48 million tons of EPA/RMP chemicalspassed through U.S. waters in 2003, the most recent year for which data are available. Thesehazardous chemicals accounted for 2% of total U.S. waterborne cargo tonnage.

Table 1: 2003 U.S. Waterborne Tonnage of EPA/RMPHazardous Cargo

Sources: 49 C.F.R. Â§ 173.2a; Army Corps of Engineers; EPA; CRS analysis. Note that DOTDivisions are subcategories within a Class.

Hazardous Cargo Shipment Frequency and Volumes

It may be appropriate to consider both size and number of shipments in an analysis of marinecargo terrorism hazards. The hazardous materials on the EPA/RMP list are included primarilybecause their chemical properties make them hazardous to human health. To be a potentiallycatastrophic threat to the general public, however, these materials must be present in large enoughvolumes to impact nearby populations in the event of a maritime release. Accordingly, the overallvolume of a hazardous material in a marine shipment becomes an important consideration whenevaluating potential public impacts of terrorist attack. Additionally, a larger number of shipmentscould potentially equate to a larger overall terrorist risk because terrorists could have moreopportunities for a successful attack, among other reasons.

Over 100,000 marine shipments of EPA/RMP hazardous cargo passed through U.S.waterways in 2003. Figure 1 summarizes the total number of shipments and average cargo tons pershipment in 2003 for the EPA/RMP hazardous chemicals as estimated by the ACE. (31) Because cargo vessels mayload or unload partial cargoes at multiple locations over the course of a single shipment, the tonnageof cargo actually carried aboard a vessel at any time may vary. Note that the data in Figure 1 areplotted on a logarithmic scale for clarity of presentation.

Figure 1: 2003 Marine Shipments of EPA/RMP Hazardous Chemicals

The EPA regulations specify minimum threshold quantities for risk planning between 500and 20,000 pounds for the EPA/RMP chemicals. The dashed line in Figure 1 represents the 20,000pound (10 ton) upper threshold above which off-site consequence plans are required for facilities onland. According to the ACE data, the average shipment volume for the hazardous chemicals in Figure 1 generally exceed the EPA/RMP 20,000 pound threshold. (32) Based on these statistics,the average waterborne shipment of most of the EPA/RMP hazardous chemicals would be ofsufficient volume to require an off-site risk management plan under the EPA's rules if the samequantity of chemical was stored on land. It is also interesting to note that each category of chemicalsin Figure 1 was typically shipped between several hundred and several thousand times in 2003. "Low frequency" and "high frequency" hazardous cargoes are not easily distinguished.

Hazardous Cargo Vessel Characteristics

Many types of marine vessels may transport hazardous cargo in bulk. These vessels havedistinct construction and operating characteristics depending upon the quantities and physicalproperties of the cargoes they are designed to carry. Cargo vessel characteristics are an importantsecurity consideration. They determine, in part, the physical vulnerability of such vessels to accidentor deliberate attack, as well as the potential consequences of an accident or attack. As Figure 2 shows, over 67% of EPA/RMP hazardous marine cargo in 2003 was shipped in tankers (liquefiedgas or chemical parcel), or self-propelled liquid chemical barges. An additional 29% was shippedin non-self-propelled liquid chemical barges. Container ships, dry cargo barges, and other vesselscarried 4% of such cargo. This section will review the characteristics of each of these vesselcategories.

Figure 2: Marine Shipments of EPA/RMP Chemicals by VesselType

Liquefied Gas Tankers

Liquefied gas tankers are oceangoing ships designed to carry one or more types of liquefiedgas cargo--gas which has been cooled, pressurized, or both, below its boiling point so it can beshipped as a liquid. Such liquefied gas cargoes include butane and propane (both referred to asliquefied petroleum gases, or LPG), liquefied natural gas (LNG), butadiene, propylene, ethylene,vinyl chloride, methyl chloride, ammonia and propylene oxide. These are all chemicals on theEPA/RMP list.

Liquefied gas tankers consist of several large and separate onboard tanks which may bepressurized, refrigerated, and insulated to accommodate different cargo needs ( Figure 3 ).International shipping codes impose extensive standards for the construction and operation of thesevessels. (33) Their cargotanks must be built to withstand high pressures or low temperatures, as necessary. Therefore, thesetanks are robust and resistant to impact damage, or flexible and able to distort without failure. Thevessels are also "double-hulled," with cargo tanks located above a double bottom and inboard of theouter hull, independent of the tankers' outer hull structures. Consequently, liquefied gas tankerspossess a level of structural integrity greater than that found in most other classes of ship, whichmakes them highly resistant to grounding and collision damage. (34) LNG tankers carry onlyLNG. Other liquefied gas tankers may simultaneously carry a combination of different cargoes, suchas butane and propylene, in different storage tanks. (35) Such combination cargoes create potentially uniquemulti-chemical hazards.

Figure 3: Typical Liquefied Natural Gas Tanker

Source: Yuasa, K., Uwatok, K., and Ishimaru, J. "Key Technologies of Mitsubishi LNG Carriers:Present and Future." Mitsubishi Heavy Industries, Ltd. Technical Review . Vol.38 No.2. June. 2001.

Liquefied gas carriers vary greatly in capacity. Fully pressurized ships may carry up to 4,300m 3 of cargo, although most can carry no more than 2,500 m 3 of cargo. (36) LNG tankers, on the otherhand, have capacities of 25,000 m 3 to 147,000 m 3 , with ships of 200,000 m 3 capacity planned fornew construction. (37) (A cargo capacity of 200,000 m 3 , is equivalent to approximately 82,000 tons of LNG.) At the upperend of this range, LNG tankers are among the largest cargo vessels in the world.

Chemical Parcel Tankers

Chemical parcel tankers are versatile vessels designed to carry a wide range of liquid andchemical cargoes, including EPA/RMP hazardous chemicals. Externally, they appear similar topetroleum product tankers, but typically can carry 10 to 60 separate cargo tanks to simultaneouslyaccommodate multiple cargoes or "parcels." They range in total cargo capacity from approximately3,000 to 50,000 tons, although most are well under 50,000 tons. (38) Figure 4 is an illustrationof a chemical parcel tanker with a cutaway view showing individual cargo tanks.

Figure 4: Typical Chemical Parcel Tanker

Source: Intl. Assoc. of Independent Tanker Owners. "Features of a Modern Chemical ParcelTanker." The Tanker Newsletter . Oslo, Norway. Issue No. 4. April 2000.

Chemical parcel tankers, like gas carriers, are governed by international constructionstandards. (39) They mayhave cargo tanks lined with stainless steel or specialized coatings, such as epoxy, zinc silicate, orpolyurethane, to ensure compatibility with a range of chemicals. The tankers have double bottomsor hulls, and maintain spaces between tank walls to prevent incompatible cargoes from coming intocontact with each other. (40) Like LPG tankers, chemical parcel tankers may carry multiplechemical cargoes of different hazardous chemicals at one time.

Liquid Chemical Barges

Liquid chemical barges are shallow draft vessels designed to carry bulk liquid chemicals,primarily in coastal regions and through inland waterways. Liquid chemical barges are similar toparcel tankers in that they may contain multiple separate cargo tanks lined with stainless steel orother special coatings. Such barges range in size from 700 tons to 3,500 tons of total cargocapacity. (41) Largerbarges transporting hazardous chemicals are typically double-hulled and self-propelled ( Figure 5 ),although smaller chemical barges may be unpowered, relying upon tugboats or towboats formovement. Unpowered chemical barges on inland waterways are approximately 52 to 54 feet wideand up to 300 feet long. (42) Inland barges usually travel river systems in groups of two toeight barges per towboat, although "linehaul" tows may consist of more than 20 barges, picking upand dropping off barges at various points along a given route. (43) Such inland barges maybe refrigerated, employing two insulated cargo tanks, each approximately 18 feet in diameter and upto 240 feet long, and each capable of carrying 1,250 to 1,500 tons of ammonia, propylene, or otherrefrigerated chemical product. (44) Pressurized cargo tanks are also available for pressurized liquidcargoes.

Figure 5: Typical Self-Propelled Liquid Chemical Barge

Source: Royal Vopak. "Photo Gallery: Barging." Internet page. Rotterdam, Netherlands. July 20,2005. http://photoshop.vopak.com/pictureGallery/page_showPictures.php?category=barging

Other Marine Vessels

Hazardous chemicals may be transported on conventional container ships in multi-modal tankcontainers, drums, portable tanks, or other cargo consignments. Roll-on/roll-off vessels may carrysuch chemicals in tanker trucks or in conventional tractor-trailers with internally packagedcargo. (45) Given the sizeof modern container ships, large quantities of a variety of hazardous chemicals may be present in acontainer ship at any time. The Jolly Rubino , for example, was reported to be carrying 3 containersof vinyl acetate, an EPA/RMP chemical, and 18 containers of other DOT toxic chemicals when itcaught fire off South Africa in 2002. (46) Hazardous chemicals must be shipped in designated cargo areasaboard these vessels. In addition to container ships, hazardous chemicals may also be shipped aboardgeneral cargo ships, container barges, ferries (in road vehicles), and other vessels.

Comparing Marine and Land Volumes

The public hazards associated with EPA/RMP hazardous cargo in a given setting areproportional to volume. Accordingly, it is informative to compare the volumes of hazardouschemicals present on marine vessels to volumes of the same chemicals in other modes oftransportation and in stationary storage facilities on land.

Land Transportation Volumes

Marine vessels, rail tank cars, and highway tanker trucks are all bulk transportation modesfor EPA/RMP hazardous chemicals. In many cases, a given shipment of hazardous cargo may bemoved sequentially by all three modes to its final destination. The maximum range in cargo capacityof rail tank cars is approximately 50 to 90 tons, depending upon the chemicals carried. (47) Containerized tankscarried on flatbed railcars may carry up to 70 tons per tank. (48) Note that rail shipmentsmay carry multiple tank cars and hazardous cargoes simultaneously. Highway tanker trucks alsocarry many EPA/RMP hazardous cargoes, such as anhydrous ammonia, chlorine, and LPG. Standardcargo capacity for these tanker trucks ranges from approximately 15 to 30 tons, depending upon thetype of cargo. (49)

Table 2: Cargo Tank Capacity for EPA/RMP TransportModes

Source: CRS

Table 2 summarizes the typical range of cargo tank capacity for the principal marine, rail,and highway tankers that transport EPA/RMP chemicals as discussed above. Note that multipletanks are usually found on liquefied gas tankers, chemical parcel tankers, and liquid cargo barges. As the table shows, marine cargo tank capacity generally exceeds the capacity of a single rail orhighway tanker truck by one or more orders of magnitude. (This is generally true for other types ofcargo as well.) Because marine tankers often carry partial cargoes, and because barge and railshipments may involve multiple barges or rail tank cars, comparing actual volumes shipped acrossthese modes is more difficult than comparing tank capacity. Based on the average marine shipmentvolumes reported in Figure 1 and the rail and highway tank capacities in Table 2 , it appears thatmany marine shipments of EPA/RMP hazardous material are larger than an individual shipment ofthe same material on land.

Chemical Facility Volumes

The EPA maintains a database of on-site chemical storage volumes for all facilities requiredto file risk management plans under the Clean Air Act, Section 112(r). Under the act, these facilitiesmust report the amount of chemical held on hand as well as the amount held in a single process. These filings may be used to estimate the maximum and average quantity of a given EPA/RMPchemical across all facilities required to file risk management plans (with off-site consequenceanalysis data). Note that these facilities are the subset of all chemical facilities with the higheston-site quantities of the EPA/RMP chemicals in a single storage location.

CRS compared average and maximum marine shipping volumes from the ACE database toaverage and maximum land storage volumes from the EPA database for nine EPA/RMP chemicals: acrylonitrile, anhydrous ammonia, chlorine, ethylene, methyloxirane, oxirane, propene, sulfurdioxide, and vinyl chloride. (50) These chemicals represent high, medium, and low volumeshipments of both toxic and flammable chemicals. The results of this comparison are summarizedin Table 3 . (Because detailed shipping and storage information for specific chemicals is proprietary,the table does not name the chemicals; they are not presented in alphabetical order.)

Table 3: Marine and Chemical Facility Volumes of NineEPA/RMP Chemicals

Sources: Army Corps of Engineers, EPA, CRS analysis.

As the table shows, for the chemicals shipped in higher volumes (#1- #4), the average marineshipments were generally larger than the average volumes stored at EPA/RMP chemical plants. Thisfinding is consistent with the practice of shipping higher volume cargo in larger vessels. The tablealso shows that the largest marine shipments were substantially smaller than the largest volumesstored at chemical plants, except for chemical #3.

Hazardous Chemical Shipments through U.S. Ports

Marine shipments of EPA/RMP hazardous chemicals either originate or terminate in U.S.ports. In some cases, port facilities serve as transportation hubs for temporary storage and transferof hazardous cargo to rail tank cars or truck tankers. In other cases, port facilities may be industrialplants that receive hazardous marine cargo directly for use in industrial processes, such aspetrochemical refining, water treatment, and fertilizer production. Some port facilities producehazardous cargo. Transportation and industrial facilities are more prevalent in some ports thanothers, so total marine shipments of EPA/RMP chemicals may vary significantly from port to port. Likewise, shipments of specific EPA/RMP chemicals vary across ports. Because security hazardsmay be related to both the volume and specific type of EPA/RMP cargo moving through a givenport, it may be helpful to examine the relative concentration of EPA/RMP hazardous marineshipments through U.S. ports.

Hazardous Chemical Cargo Ports

There are more than 360 commercial ports in the United States containing approximately3,200 cargo and passenger handling facilities. (51) According to ACE statistics, EPA/RMP hazardous chemicalswere shipped through 113 of these ports in 2003. Of these 113 ports, the top 30 handledapproximately 95% of EPA/RMP hazardous cargo tonnage. For purposes of policy discussion,these 30 ports are listed in Table 4 in alphabetical order, along with the two categories of hazardousmarine cargo shipped in greatest tonnage through each port. Note that additional EPA/RMPhazardous cargoes not listed in Table 4 may also be shipped in large volumes through a given port. For example, 22 EPA/RMP chemicals were shipped through the port of Baton Rouge in quantitiesexceeding 2,500 tons in 2003. Furthermore, volumes of a given type of cargo (e.g., LPG) in one portbear no relation to volumes of the same type of cargo in any other port. Marine shipments ofEPA/RMP hazardous chemicals in the remaining 83 ports that handle such cargo may be no less asecurity concern than shipments in the top 30 ports. An attack on a single hazardous cargo vesselmay have serious public consequences independent of other shipments through a given port.

As Table 4 shows, the top 30 hazardous chemical ports are found in 15 states. Over half ofthese ports are in the Gulf of Mexico--in Texas (9 ports), Louisiana (5 ports), Alabama (1 port),Florida (1 port), and Mississippi (1 port). All of the top 30 ports in Table 4 are classified by theACE as coastal, except for Huntington, WV, which is located on the Ohio River. (52) No Great Lakes ports areon the list. The mix of principal EPA/RMP hazardous chemicals varies considerably from port toport. The chemicals listed most frequently among the top two hazardous cargoes shipped throughthese ports are LPG (13 ports) and ammonia (12 ports). LPG (typically propane) is an extremelyflammable and potentially explosive gas, heavier than air, and shipped under pressure in liquefiedform. (53) Thecharacteristics of ammonia, a toxic gas, were summarized earlier in this report (page 8).

Table 4: Top 30 Ports Handling EPA/RMP Hazardous Cargo in2003

(in Alphabetical Order )

Sources: Army Corps of Engineers, EPA, CRS analysis.

The list of ports in Table 4 is derived solely from estimates of EPA/RMP hazardous cargovolumes, which are only one of many factors that may affect the terrorism risk in U.S. ports. Otherkey factors include:

DOT hazardous cargo shipments (e.g., gasoline,explosives);

non-chemical cargo shipping hazards (e.g., dirtybombs);

marine passenger traffic (e.g., ferries, cruise ships);

hazardous materials sites or critical infrastructure onland;

proximity to populations on land;

physical configuration of the ports;

threat intelligence and vulnerability assessments.

The Department of Homeland Security (DHS) does consider these other factors in its PortSecurity Grant Program, which provides competitive security enhancement grants to U.S. ports underthe DHS Appropriations Act of 2005 ( P.L.108-334 ). For the FY2005 program, DHS evaluated the129 largest U.S. ports using its risk-based formula to identify 66 ports eligible to apply for thegrants. (54) Table 4 shows that 24 of the top 30 hazardous material ports are among the 66 ports eligible to apply forDHS port security grants.

Coast Guard Efforts to Secure Hazardous Cargo

The Coast Guard is the lead federal agency assigned to promote U.S. maritime security,including vessel and port security. Among other duties, the Coast Guard tracks, boards, and inspectscommercial ships approaching U.S. waters. A senior Coast Guard officer in each port oversees thesecurity and safety of vessels, waterways, and many shore facilities in the geographic area.

In pursuit of its mission to protect life, property, and the marine environment, the CoastGuard has a history of special concern for ships and barges carrying hazardous cargo. Coast Guardsafety and environmental protection regulations have long specified how vessels carrying such cargomust be constructed and operated, how hazardous cargo should be transferred at waterfront facilities,and what procedures should be used to respond to accidental cargo releases. (55) Compliance with thesesafety regulations could help mitigate the damage from a terrorist attack, for instance, by minimizingthe amount of cargo released, and might also help deter an attack. Prior to 9/11, however, the CoastGuard had only limited regulations directed specifically at terrorism; existing marine anti-terrorismlaw was primarily concerned with cruise ships. (56) The Coast Guard's maritime security regulation has since beenexpanded.

New Maritime Security Regulation

Since the 9/11 attacks, the Coast Guard has begun to distinguish more clearly between safetymeasures designed to prevent accidents and security measures designed to prevent sabotage orsubversive acts. The Coast Guard's area maritime security committees, which are led by localcaptains of the port, and include chemical sector representatives, have assessed specific portvulnerabilities and created plans to address those vulnerabilities. (57) These plans evaluate theoverall susceptibility of marine targets, their use to transport terrorists or terror materials, and theiruse as potential weapons. The plans also address how federal, state, and local resources will bedeployed to prevent terrorist attacks. While the vulnerability assessments focus on vessels andfacilities under Coast Guard jurisdiction, some scenarios involve other vital port infrastructure likebridges, channels, and tunnels. (58) The Coast Guard has used these assessments in augmentingsecurity of key marine assets and in developing the agency's new maritime security standards underthe Maritime Transportation Security Act of 2002 (MTSA, P.L. 107-295 ). (59)

The Coast Guard also has led in the creation of the International Ship and Port FacilitySecurity Code (ISPS Code) promulgated by the International Maritime Organization, a UnitedNations organization that establishes standards for the safe and secure operation of ships andports. (60) The ISPSCode, which went into effect on July 1, 2004, largely parallels the MTSA requirements. The ISPSCode requires that every ship and certain port facilities around the world draw up a security plan tobe approved by their national government. These security plans must indicate the operational andphysical security measures to be taken under three tiered threat levels (normal, medium, and high). Every ship and port must also designate a security officer to ensure that the ISPS Code isimplemented; must deploy required security equipment (e.g., vessel tracking devices); must monitorand control access of people and cargo at the port and aboard the vessel; and must ensure thatsecurity communications are readily available. According to the Coast Guard, by July 1, 2004, theservice reviewed and approved the security plans of over 9,000 vessels under the provisions of theMTSA and ISPS Code. The Coast Guard also completed on-site inspections of thousands of thesevessels six months thereafter to ensure the plans were being implemented as approved. In additionto these vessel inspections, the Coast Guard has completed security assessments of the nation's 55"most economically and militarily strategic" ports. (61)

Hazardous Cargo Vessel Regulations

In addition to enforcing MTSA regulations and the ISPS Code, the Coast Guard has takenspecific measures to help prevent a terrorist attack against hazardous chemicals vessels and otherhigh consequence shipping. The Coast Guard has evaluated the vulnerability of marine tankers toseveral different types of attack, such as "a boat loaded with explosives" or "being commandeeredand intentionally damaged." (62) The agency is also conducting a special assessment of inlandbarges carrying certain dangerous cargoes to evaluate their vulnerabilities and analyze potential blastconsequences. (63) TheCoast Guard requires all U.S. bound vessels and inland barges carrying hazardous chemicals toreport information about the vessel, crew, cargo, and voyage four days prior to the ship's arrival ordeparture. Based on this information and other intelligence, the Coast Guard determines thepotential security risk that a vessel may pose, whether it may enter U.S. waters, and what actions theagency will take to ensure secure transit. The Coast Guard may board a vessel before or duringentrance to a harbor and may post armed sea-marshals on the bridge or at the engine room to preventunauthorized access during harbor transit. Ships carrying hazardous cargo may be escorted by CoastGuard patrol boats that enforce a moving security zone around the vessel while it transits a harbor( Figure 6 ) and while moored at a waterfront terminal. (64) While moored, vessels carrying hazardous cargo may be requiredto provide their own roving patrols on deck and at the terminal. During periods of high threat levels,or in certain sensitive areas of a harbor, non-commercial traffic may be banned. The Coast Guardalso maintains 13 Maritime Safety and Security Teams nationwide which can perform securityoperations at any given port area(s) when needed.

Maritime Domain Awareness

The Coast Guard is trying to better distinguish suspicious from legitimate harbor activity inan effort the service refers to as "maritime domain awareness." Consistent with the ISPS Code andMTSA, cargo and passenger vessels calling at U.S. ports are required to be outfitted with AutomaticIdentification System (AIS) transponders which allow shore-side facilities and other ships to trackvessel movement. (Smaller craft, such as fishing and recreational boats, are not required to installAIS transponders). (65) The Coast Guard has installed AIS receivers at ten port areas to date, and plans to install receiversat all remaining U.S. ports. The Coast Guard is also developing "joint harbor operations centers"(JHOCs) in U.S. harbors in a model simialr to air traffic control towers at airports. JHOCs wouldhave various equipment to track and monitor vessel traffic in a harbor, such as AIS, radar, voicecommunications with ships via radio, closed-circuit television, and personnel with binoculars. Theywould also have access to intelligence databases and be staffed with other federal security agenciesand local law enforcement in order to better coordinate a response should a threat materialize. Through its "Waterways Watch" program, the Coast Guard is enlisting the eyes and ears of therecreational boating public on how to identify and report suspicious activity. The Coast Guard isworking with the Transportation Security Administration to develop a more secure merchant marinercredential and a credentialing card for landside workers, such as longshoremen and truckdrivers. (66)

Figure 6: Coast Guard Patrol Boats Escorting a Chemicals Barge

Source : U.S. Coast Guard, 8th Dist. "Photography: Marine Safety." Internet page. Feb 14, 2005. http://www.piersystem.com/external/index.cfm?cid=425&fuseaction=EXTERNAL.press&doctypeID=4758 .

NOAA Hazardous Materials Response

The National Oceanic and Atmospheric Administration (NOAA) maintains hazardousmaterial emergency response-related capabilities which may be used by the Coast Guard and otheragencies to plan for, or quickly respond to, an accident or attack on a hazardous chemical vessel. These capabilities include the CAMEO program, an integrated set of chemical dispersion softwaremodels jointly developed by NOAA and EPA for first responders and emergency planners. TheCAMEO program includes a database with response recommendations for over 6,000 chemicals, anelectronic mapping program, and a model that predicts the movement of chemical gases in theatmosphere. (67) NOAAhas also linked its three operational air dispersion models to improve its support to emergencyplanners and first responders. According the agency, NOAA partnered in 2002 with the Coast Guardand the Office of Naval Intelligence "in conducting risk assessments on 50 of the most hazardouschemicals stored at or shipped in bulk through U.S. ports." (68) CRS is not aware of anypublicly available information related to these risk assessments. NOAA, along with the DHS, is alsocurrently helping to coordinate federal chemicals emergency response through the InteragencyModeling and Atmospheric Assessment Center, which provides custom products and a single pointof contact for all-hazards dispersion modeling predictions and assessments. (69)

Private Industry Initiatives

Industry groups also have taken steps to promote the security of hazardous marine cargo. When evaluating hazardous materials regulations, the Coast Guard receives input from the ChemicalTransportation Advisory Committee (CTAC). CTAC is an advisory group made up of membersselected from the following sectors associated with marine transportation of hazardous materials:chemical manufacturing, vessel design and construction, occupational safety and health, marineenvironmental protection, and the marine transportation of chemicals. In October 2002, CTACformed a Subcommittee on Hazardous Cargo Transportation Security for the purpose of assessingvulnerability, promoting industry security awareness, and consequence management. The AmericanWaterways Operators (AWO), a trade association of barge operators, in consultation with the CoastGuard and Army Corps of Engineers, created a model vessel security plan to thwart potential terroristattacks on the inland waterway system. The plan includes an appendix which lists cargoes AWOhas deemed "high consequence." (70) The Chemical Distribution Institute (CDI) is a non-profitorganization financed by the chemical industry which serves as an industry "self-policing"mechanism. CDI inspects and issues audit reports on the world's fleet of chemical and LPG tankers,tank storage terminals, and container ships carrying hazardous cargo. (71) Separately, the AmericanChemistry Council has also issued transportation security guidelines for the chemical industry. (72)

Policy Issues

Securing hazardous chemicals against terrorist attack is a priority in U.S. homeland securitypolicy. Given the large quantities of such chemicals found aboard marine vessels on U.S. waterwaysand in U.S. ports, it is apparent that maritime security of chemical cargo is necessarily included inthis priority. Although Congress and the Coast Guard have put in place new maritime securitymeasures since 9/11, several policy issues related to hazardous marine cargo may warrant furtherCongressional attention. The most significant concerns are risk uncertainty, resource availability,and security effectiveness, although other issues have also emerged in recent policy discussions.

Terrorism Risk Uncertainties

Terrorism risk is generally defined as the product of threat, vulnerability, and consequence. Significant uncertainties exist across all three of these factors as they relate to hazardous marinecargo. The potential threat posed by terrorists targeting ships in U.S. waters, for example, has beenthe subject of debate since 9/11. Although experts acknowledge the general threat information putforth by government agencies, some believe that public concern about specific threats to hazardouschemicals shipping is overstated and should not impede maritime trade. (73) Others assert that terroristshave demonstrated both the desire and capability to attack such shipping with the intention ofharming the general population. (74) The basis of such conclusions is open to question, however, dueto the inherent uncertainty of threat intelligence and the shifting goals and methods of potentialattackers. As the Federal Energy Regulatory Commission has remarked, "unlike accidental causes,historical experience provides little guidance in estimating the probability of a terrorist attack." (75)

Vulnerability and consequence analysis of marine chemical hazards also may face importantuncertainties. The Coast Guard reports having approved mandatory security vulnerabilityassessments and security plans for thousands of vessels as required under the MTSA and ISPS codes. NOAA reports having established a partnership with the Coast Guard to conduct hazardous chemicalrisk assessments at U.S. ports. Notwithstanding these Coast Guard activities, some analysts suggestthat the potential vulnerabilities and consequences of a terrorist attack on (or with) a hazardousmarine cargo vessel are not well understood. Recent public controversy about terrorist risks to LNGshipping, for example, has been largely driven by conflicting vulnerability and consequence studiesfrom a variety of government and private sector groups. (76) The security sensitivity of such assessments and planscomplicates efforts to evaluate them. Little public information is available, for example, on thephysical vulnerabilities of different types of marine vessels to terrorist attacks with weapons orimprovised explosives, although the Cole and Limburg attacks suggest that such vulnerabilities exist. Furthermore, while there is a body of public marine research related to accidental release ofhazardous chemicals, little appears directly related to intentional release, which may havesubstantially different characteristics. Vessel vulnerability assessments and security plans are centralto U.S. maritime security strategy, but their value and effectiveness for hazardous chemicals carriersmay be limited if operators lack a full understanding of vulnerability and consequence, especiallyfor attacks affecting the general public.

It may be impossible for federal officials to determine with precision the risk of terror attackson hazardous marine cargoes. Nonetheless, any reduction in risk uncertainty would aid inprioritizing maritime security activities. For example, the Coast Guard may be able to focus its portsecurity efforts through ensuring timely reception of the most relevant intelligence information fromfederal intelligence agencies. Security experts may further reduce risk uncertainty through researchand analysis of vessel vulnerabilities and chemical attack consequences. Such analyses may benefitfrom the use of standard models and methodologies, such as those maintained by NOAA, those usedby EPA for chemical plant releases on land, or the model developed for LNG tankers in conjunctionwith recent marine terminal siting applications. (77) A federal role may be important when performing such securityanalysis to help ensure methodological consistency across chemicals, vessel types, locations, andagencies.

Maritime Security Resources

The costs associated with hazardous marine cargo security and the potential diversion ofCoast Guard and other government agency resources from other activities have been a concern topolicy makers. (78) According to Coast Guard officials, the service's maritime security expenditures are not allincremental, since they are part of the Coast Guard's general mission to protect the nation's watersand coasts. Nonetheless, Coast Guard staff have acknowledged that resources dedicated to securingmarine shipments of hazardous cargo might be otherwise deployed for boating safety, search andrescue, drug interdiction, or other missions. (79) A recent Government Accountability Office (GAO) studyreported that security activities grew from 4 percent to 34 percent of the Coast Guard's total annualresource hours in the two years following 9/11. (80)

President Bush requested $8.1 billion for the Coast Guard in FY2006. Of this total, thePresident requested $2.2 billion for port, waterway, and coastal security, which is a 6% increase overthe FY2005 enacted amount. Hazardous marine cargo security is funded from the Coast Guard'sgeneral maritime security budget, so it is not a line item in the FY2006 DHS budget request. However, the Coast Guard's FY2006 budget does seek an additional $11 million in general maritimesecurity funding over FY2005 levels. These resources are for new small response boats andassociated crew to increase the Coast Guard's operational presence and response posture, enforcesecurity zones, and escort high interest vessels. (81) The budget also includes $5.7 million to implement a nationwidevessel monitoring system and $87.4 million to increase surveillance of vessels by aircraft.

State and local agencies are also seeking more funding to offset the costs of hazardous marinecargo security. These funding concerns are most clearly illustrated in the case of LNG tankers,which may cost the public up to $80,000 to secure each time they deliver a shipment. (82) State and local police andemergency services agencies pay a significant share of these costs. They believe LNG security costsmay force them to divert limited local resources from other important public services. (83) Acknowledging suchconcerns, federal officials have recommended that new LNG terminal operators pay the costs of anyadditional maritime security or safety needed for their facilities. (84) The Energy Policy Actof 2005 requires private and public sector cost-sharing for LNG tanker security (Sec. 311d). Nonetheless, because the accounting of security costs is ambiguous and tied to uncertain sources offederal funding, such as DHS port security grants, some government officials continue to voiceconcern over LNG security costs. (85) Furthermore, some LNG companies have resisted suggestionsthat they pay more for public security, reasoning that the federal, state, and local taxes they payshould cover public law enforcement and emergency services. (86) Others have expressed awillingness to pay for "excess" security only if it exceeds the level of security service ordinarilycommensurate with corporate tax payments. (87)

The security costs associated with LNG shipments may not be indicative of the costs tosecure other EPA/RMP hazardous marine cargo. New security technology, more specific threatintelligence, and changing threat assessments may all help to lower hazardous marine cargo securitycosts in the future. Nonetheless, the costs to public agencies to secure hazardous marine cargo fromterrorist attack appears significant and may warrant a review of associated cost-sharing mechanisms.

Effectiveness of Security Measures

As this report notes, the Coast Guard has in place a range of security measures to protecthazardous chemicals shipping. Nonetheless, the effectiveness of these measures is regarded as anopen issue. Given the current understanding of general marine threats, some question whether theCoast Guard efficiently deploys the security resources it has. (88) Others question whetheradequate measures are in place to evaluate the Coast Guard's security activities. For example, theGAO has concluded:

Although there is widespread agreement that actionstaken so far have led to a heightened awareness of the need for [maritime] security and an enhancedability to identify and respond to many security threats, assessing the degree of progress in makingthe nation more secure is difficult. Thus far, seaport security actions ... lack performance measuresto define what these activities are intended to achieve and measure progress toward these goals. (89)

Addressing hazardous cargo, some specifically question whether Coast Guard security activities adequately address relative terrorism risks within and across ports based on quantitativerisk analysis. Within a given port, for example, there may be a greater or lesser risk from terroristattacks on ammonia tankers than from dirty bombs hidden aboard container ships. The Coast Guardstates that its internal maritime security plan identifies "high risk cargos" and conducts operationsto address those risks. (90) Nonetheless, given the terrorism risk uncertainties associated with hazardous chemical vessels andthe competing demands for Coast Guard resources, some question whether the level of Coast Guardsecurity for hazardous chemicals vessels appropriately reflects their relative risk. (91) Because Coast Guard portcaptains have considerable discretion in the deployment of security resources within their ports,some observers also question whether similar chemical shipments posing similar terrorism hazardsreceive different levels of protection from one port to another. While differences in protection maybe appropriate in some instances, such a situation could lead to excessive security of hazardousmarine cargoes in some ports and inadequate security in others. In its oversight of the Coast Guard'ssecurity activities, Congress may take steps to assess the effectiveness of the agency's hazardousmarine cargo activities in the context of its larger maritime security responsibilities.

Emergency Response

Emergency response to marine chemical attacks is another concern among security analysts. The Homeland Security Council's national planing scenario involving chemical cargo ships assumes350 deaths and 1,000 hospitalizations resulting from an attack. (92) Others have suggestedhigher casualties for specific types of chemical tanker attacks in shipping channels near denselypopulated areas. If a terrorist attack succeeded in injuring or killing such large numbers of people,it might overwhelm federal and local emergency agencies and medical facilities. An attack involvingone or more toxic chemicals might further complicate emergency response by imposing specialdemands on emergency response teams and requiring specialized medical treatment for poisoningand burns. Salvage of a vessel damaged or sunk in such an attack could be an additional problem,due to the chemical hazard and other limitations among U.S. marine salvage companies. (93)

Because of the hazardous cargo terrorism risk, it may be judged to be prudent for emergencyand medical authorities near potentially affected waterways to develop specific prospective measuresto deal releases of chemical cargoes most relevant to their region. Federal or private sectorassistance in the form of funding or expertise might be utilized to support such efforts, especially forcommunities with insufficient capabilities to develop emergency response plans. The DOT'sHazardous Materials Emergency Preparedness Fund (created in the Transportation Equity Act of2005, Sec. 7114d), and the DHS's Homeland Security Grant Program are two potential source offunding for marine chemicals emergency response plans, but Congress may opt to considerothers. (94) Theemergency response plan and cost-sharing provisions for coastal LNG terminals and tankers in TheEnergy Policy Act of 2005 (Sec. 311d) may be an alternative legislative model for such planning.

Conclusions

This report shows that marine shipments of EPA/RMP hazardous chemicals are comparablein volume to quantities stored at large chemical plants, and are typically many times larger thanshipments in individual rail or highway tankers. Marine vessels carrying hazardous chemicals oftenpass near populated areas along U.S. waterways and through the largest and most commerciallyimportant U.S. ports. Available studies and anecdotal evidence suggest that these shipments maybe attractive terrorist targets and, if successfully attacked or used as a weapon, could causecatastrophic injuries among the general public.

Both government and industry have taken numerous steps to try to improve maritime securityof hazardous chemical cargo. The MTSA gives the Coast Guard clear and far-ranging authority overthe security of hazardous marine shipping. In its efforts to fulfill this legislative mandate, the CoastGuard is continuing to evolve its security activities. As oversight of the federal role in marinechemicals security continues, Congress may raise questions concerning terrorism risk uncertaintyand efforts by federal agencies and the private sector to rigorously evaluate that risk. Congressionalpolicy makers may also analyze whether the Coast Guard, other government agencies, and theprivate sector have sufficient resources to secure hazardous chemical cargo commensurate with thatrisk and whether current security measures will be effective against a terrorist attack. Since a marineattack is possible even under tight security, evaluating the emergency response capabilities of coastalcommunities exposed to chemical shipping hazards may be of interest as well.

In addition to these specific issues, Congress may assess how the various elements of U.S.hazardous chemicals marine security fit together in the nation's overall strategy to protect the publicfrom hazardous chemicals and cargo. Bulk quantities of hazardous chemicals are found in marinevessels, in rail and highway tankers, and in chemical facilities on land. As noted earlier in thisreport, the same physical shipment of a chemical may pass sequentially through all these sectors. Balancing the nation's chemicals security resources across these sectors is a policy challenge becausemarine transportation, land transportation, and chemical facilities fall under different homelandsecurity authorities and regulations. Limited vulnerability and consequence information, especiallyfor marine transportation, complicates this problem by making it difficult to compare terrorism riskscenarios across sectors, even for the same chemical hazard. Without such a comprehensiveperspective on hazardous chemical risks, security analysts may have difficulty identifying whichchemicals assets to protect and how well to protect them with the limited security resourcesavailable. Likewise, diverting marine resources away from safety to enhance security might furtherreduce terror risk, but increase overall risk, if safety programs become less effective as a result. Reviewing how these security priorities and activities fit together to achieve common goals couldbe an oversight challenge for Congress.

Appendix 1: DOT Hazardous Cargo Ranking

Source: 49 C.F.R. Â§ 173.2a. Note that DOT Divisions are subcategories within a Class.

Appendix 2: EPA Hazardous Chemicals Requiring Clean Air Act Off-site Risk Management Plans

Sources: 40 C.F.R. Â§ 68, 49 C.F.R. Â§ 173.2a

Appendix 3: Army Corps of Engineers Marine Commerce Data

The Army Corps of Engineers (ACE) collects, processes, and archivesdetailed marine commerce statistics through its Waterborne Commerce StatisticsCenter (WCSC). These statistics are used by the ACE primarily to plan new capitalprojects and manage existing projects. The ACE maintains separate domestic andforeign commerce databases. The domestic database records domestic and foreignvessel trips and tonnages by commodity for U.S. ports and waterways. The foreigndatabase records waterborne commerce between the U.S. and foreign countries byU.S. port, foreign port, foreign country, commodity group, and tonnage. Vessel typesinclude dry cargo ships and tankers; barges (loaded and empty); fishing vessels;towboats (with or without barges in tow); tugboats; crew boats and supply boats tooffshore locations; and newly constructed vessels from the shipyards to the point ofdelivery. Vessels remaining idle during a monthly reporting period are also reported.Under federal law, vessel operators must report domestic waterborne commercialmovements to the ACE. (95)

Limitations of the ACE Waterborne Commerce Data

The ACE waterborne commerce databases were not developed to support thetype of chemical-specific analysis presented in this report. However, they may beused for that purpose subject to certain significant limitations and caveats . At therequest of CRS, the ACE provided its best estimates of EPA/RMP cargo statisticsderived from the available data. Based on a review of more limited shipping andhazardous chemicals data from other sources, CRS believes the ACE estimates aresufficiently accurate to warrant inclusion in this report. However, the values reportedhere should be viewed strictly as estimates, with the following key caveats .

Cargo Classification. The ACEdatabases identify cargos using two sets of standardized commodity codes--aninternal WCSC code, and the United Nations (UN) international standard code. Insome cases, these commodity codes do not consistently or uniquely correspond to theindividual hazardous chemicals in the EPA/RMP list, which are identified by theirChemical Abstract Service (CAS) registry numbers as assigned by the AmericanChemical Society. Such inconsistencies arise either from commodity aggregation ordifferences in definition. CRS has attempted to identify and correct for theseinconsistencies to the extent possible through comparison of WCSC and UN codes,and consultation with classification experts. For example, the WCSC systemclassifies LNG and LPG under the same 5-digit code (34000). Using LNG trade datafrom the Department of Energy, CRS was able to separate the LNG and LPGvolumes for this report. Nonetheless, shipment estimates reported for a number ofother EPA/RMP chemicals likely include some volume of other chemicals not on theEPA/RMP list. Alternatively, shipments of certain EPA/RMP chemicals may beincluded in the shipment totals for a similar EPA/RMP chemical. (96)

Cargo Volumes. As noted earlierin this report, chemicals cargo vessels may load or unload partial cargoes at multiplelocations over the course of a single shipment. The ACE data report the movementof cargo at each of these loading and unloading points, but cannot report the totaltonnage of cargo actually carried aboard a vessel at any time.

Data Quality. The ACEwaterborne commerce databases contain millions of records. Like any database ofthis size, errors in data classification, entry, and processing may appear in summarystatistics. Furthermore, CRS's data request involved new and complex queries of theACE databases. The ACE employs a rigorous internal review process for dataanalysis and reporting to minimize the infiltration of such errors into its analyticproducts. Nonetheless, CRS identified inconsistencies in the ACE estimates whichthe ACE was able to correct. It is possible, however, that additional, dataquality-related errors have escaped both the notice of the ACE and CRS.

Legal Restrictions on ACE Commerce Data Release

The ACE waterborne commerce databases contain detailed commercialinformation about private companies. This report includes only summary estimatesof chemicals shipping data and does not associate shipping data for any specificchemical with any named vessel or operating company. ACE data at the level ofindividual shipments, vessels, or operators is considered privileged information notfor public release under 18 U.S.C. Â§ 93.905. CRS products are not prepared forgeneral public distribution.