5
Monitoring

Monitoring of ballast water has two major purposes in the context of current efforts to control introductions of nonindigenous aquatic nuisance species. First, monitoring is needed to audit ballast water control methods and check for compliance with regulations or guidelines; therefore it is an integral part of the ballast water management process. Second, monitoring is a research and development tool that permits assessment of the effectiveness of ballast water treatments, allows increased understanding of the nonindigenous species problem, and may assist in developing plans to manage ballast water. The use of monitoring for auditing is likely to become increasingly important as implementation of ballast water guidelines becomes more widespread (see Chapter 3).

Compliance with existing mandatory requirements for changing ballast water prior to entering the Great Lakes is checked by measuring salinity (see Chapter 3). It is the committee's understanding that the requirements in the Great Lakes—and other future regulations—could never be satisfactorily enforced without supporting monitoring protocols. ''Spot check" procedures will be needed to indicate (either directly or indirectly) whether the densities of organisms, numbers of species, numbers of specific non-native species, or other such indicators in discharged ballast water have been reduced to the required levels, in the same way current checks at ports and airports serve to enforce compliance with quarantine regulations. Monitoring methods used for such "quarantine checks" will need to address issues of verification, accountability, and responsibility and must be supported by appropriate record keeping.

As noted in the preceding chapter, the committee determined that there is currently no off-the-shelf technology (i.e., technology transferable without modification) capable of completely sterilizing ballast water cheaply and effectively,



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5 Monitoring Monitoring of ballast water has two major purposes in the context of current efforts to control introductions of nonindigenous aquatic nuisance species. First, monitoring is needed to audit ballast water control methods and check for compliance with regulations or guidelines; therefore it is an integral part of the ballast water management process. Second, monitoring is a research and development tool that permits assessment of the effectiveness of ballast water treatments, allows increased understanding of the nonindigenous species problem, and may assist in developing plans to manage ballast water. The use of monitoring for auditing is likely to become increasingly important as implementation of ballast water guidelines becomes more widespread (see Chapter 3). Compliance with existing mandatory requirements for changing ballast water prior to entering the Great Lakes is checked by measuring salinity (see Chapter 3). It is the committee's understanding that the requirements in the Great Lakes—and other future regulations—could never be satisfactorily enforced without supporting monitoring protocols. ''Spot check" procedures will be needed to indicate (either directly or indirectly) whether the densities of organisms, numbers of species, numbers of specific non-native species, or other such indicators in discharged ballast water have been reduced to the required levels, in the same way current checks at ports and airports serve to enforce compliance with quarantine regulations. Monitoring methods used for such "quarantine checks" will need to address issues of verification, accountability, and responsibility and must be supported by appropriate record keeping. As noted in the preceding chapter, the committee determined that there is currently no off-the-shelf technology (i.e., technology transferable without modification) capable of completely sterilizing ballast water cheaply and effectively,

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while also meeting criteria for safety, compatibility with ship operations, and environmental acceptability. Thus, the degree of effectiveness of treatment technologies needs to be measured, particularly during the evaluation of prototype systems. Monitoring ballast water before and after treatment will permit a quantitative assessment of treatment effectiveness. Ultimately treatment effectiveness will be tailored to meet the levels for ballast water discharge defined by regulatory authorities. Monitoring is also important as a research tool to enhance the present limited understanding of the biology of introductions, thereby facilitating the development of effective ballast water management strategies, including a plan for managing ballast water. For example, the presence of dense populations of one or more nonindigenous species of concern could indicate to the master that ballast should not be taken on unless absolutely necessary. Monitoring will also aid in assessing the effectiveness of regulations and guidelines for managing ballast water. This chapter provides a discussion of the issues associated with monitoring ballast water, whether for auditing or R&D purposes. As with ballast water treatment, shipboard monitoring appears to offer the greatest flexibility, although other possibilities are addressed. Opportunities exist to measure a wide range of ballast water parameters—in addition to salinity—that might be helpful for monitoring purposes. The committee has identified promising approaches, both near term and long term, and has also considered levels of monitoring that might be needed in conjunction with different options for managing ballast water. Many monitoring procedures and approaches appear promising, but none has yet been used routinely on board ships. Like the candidate technologies for treating ballast water discussed in Chapter 4, shipboard application of monitoring systems introduces additional requirements and constraints on equipment and its operation in comparison with land-based industrial applications. The characteristics of an effective shipboard monitoring system for supporting strategies of managing ballast water can be summarized as follows: allows rapid data collection permits unambiguous detection of unwanted biological material or indicator organisms is safe, rugged, and relatively inexpensive to install and operate occupies minimum space, allowing monitoring to be performed in situ aboard ships without impeding other onboard operations allows the necessary monitoring to be performed as quickly as possible, so as not to put undue burden on the ship's crew permits effective monitoring by personnel with minimum training requires a minimum of complex procedures, such as chemical extraction These characteristics may not be realized in a single automated procedure, and some compromises may be necessary to achieve a workable monitoring method. As discussed below, the monitoring method in any given situation will

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be closely tied to the methods for controlling and managing ballast water to mitigate risk effectively. MONITORING SCENARIOS Vessels arriving at a load port can be in one or more of three ballast conditions: Category 1. No ballast change conducted. The vessel arrives with water as ballasted in the port-of-origin or of unknown or mixed origin(s). Category 2. Ballast change conducted. The vessel arrives with some proportion of the original water having been changed in the open ocean. Arriving water can range from original water diluted with open-ocean water to almost entirely open-ocean water with traces of original water remaining. Category 3. Onboard ballast treatment conducted. The vessel arrives with some or all of its ballast water having been treated in some fashion using physical, chemical, or mechanical techniques, as described in Chapter 4. A vessel could reflect one or more of the aforementioned conditions because its ballast tanks may contain ballast water from different regions. Thus, different ballast tanks may have been subjected to different treatments. Category 2 (ballast change conducted) represents the most probable ballast treatment scenario because, subject to safety constraints, a ballast change is the most effective treatment option currently available on board vessels. Changing ballast water will quite possibly remain the principal option available in the foreseeable future, unless international bodies agree to more stringent regulations. In general, category 1 vessels (no ballast change) are likely to present a greater risk as potential inoculators of nonindigenous species than category 3 vessels (onboard treatment). Although most category 1 ships would be considered "higher risk" vessels, exceptions may occur when vessels are transiting climatic extremes, when they ballast in polar waters and deballast in tropical waters, for example, or when they move between fresh water and salt water. ALTERNATIVES TO SHIPBOARD MONITORING The discussion in this chapter focuses on shipboard monitoring. However, in some instances it may be impractical or too expensive to install onboard monitoring systems. It has been suggested that a vessel might take ballast water samples at the ballast load port and forward them to the destination port for analysis. Samples (including replicates) would need to be taken using specialized equipment and an appropriate, approved methodology because it is difficult to collect representative samples of ballast water, including the sediment. Samples would

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then be sent by air freight to registered facilities capable of testing ballast water and sediment samples to internationally acceptable criteria. At present no such testing facilities exist, and advanced biological analysis involving taxonomic identification to species level is both costly and time-consuming (see below). However, in principle, if shore-based analysis indicated that some form of treatment was required, the vessel could be notified accordingly. If the voyage passage time were long enough, treatment could be performed in transit. A simplified version of this "sampling and dispatch" approach has been used by the Australian Quarantine and Inspection Service in the case of an identified chronic carrier of toxic dinoflagellate cysts operating between Japan and Australia. Extending the "sampling and dispatch" approach to a range of organisms of concern is a significant challenge in terms of both sampling and testing. In addition, critical ballast introductions—such as the Asian river clam in San Francisco Bay—would not have been recognized as significant potential invaders if they had been found and identified in ballast water samples prior to their introduction. Under some circumstances, ports may choose to monitor their water to provide additional reassurance about the effectiveness of strategies used to manage ballast water in reducing the risk of introductions. For example, some port-water sampling studies have been conducted in Australia to determine the presence or absence of potentially harmful organisms that could be transmitted to other Australian ports (Kerr, 1994). Formal certification that a ballasting site (e.g., cargo discharge port) is, and continues to be, free of a given species requires a rigorous, continuing, scientific program (Carlton et al., 1995). Studies would need to be updated every three to five years—and possibly more frequently—to determine whether a species that was previously absent had been introduced. Baseline sampling of ports for specific organisms to standardized, internationally accepted criteria would be helpful in determining the risk associated with a voyage between specified ports. The port of ballast water uptake could provide information that would assist vessel owners and operators in deciding upon the ballast water management or treatment methods needed during transit to meet requirements at the receiving port. This procedure could assist regulating authorities in more effective monitoring of possible introductions of a species known to be of concern. This approach would also require a costly, continuing program. LEVELS OF MONITORING The committee considered levels of monitoring for vessels in categories 1 and 2 (no ballast change conducted and ballast change conducted). When vessels have undertaken specialized onboard ballast treatment (category 3), monitoring of the method's effectiveness will be sensitive to the treatment class (see below). The three proposed levels of monitoring are as follows:

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TABLE 5-1 Approaches to Monitoring Options for managing ballast water No change of ballast water Open-ocean ballast change Treating ballast water onboard →→→→risk decreases→→→→ Likelihood of scenario occurring Currently most probable scenario. Most probable scenario for most vessels within near future. Possible in the near future if mandated. Condition of ballast water Original, as ballasted at port of origin, or unknown. Ranges from diluted ballast water from port of origin to fully changed ocean water. Organisms removed and/or inactivated by various treatment methods. →→→→ monitoring effort decreases →→→ Monitoring approach Monitoring complex because many original organisms present. Start with level II/III unless transiting climatic extremes. Levels I, II, and/or III as necessary to determine that water meets required standards. Monitoring dependent on treatment method(s) Level I. Log of change events and basic water quality parameter descriptions Level II. Basic bioactivity and/or indicator species description Level III. Advanced biological or chemical analyses Each of these levels of monitoring requires increasingly higher numbers of personnel, levels of expertise, and expenditures to conduct the analyses indicated below. Level I monitoring is the simplest and least costly; level III is the most complex and expensive. Levels I and II are designed to be conducted on board vessels at sea, using automated equipment (although manual measurements could easily be made). Level III monitoring would probably require an onshore laboratory, using current technology. Monitoring would be conducted at the lowest level necessary to demonstrate that ballast water meets required standards (see Table 5-1). Failure to meet criteria for effective risk control at one level would necessitate more sophisticated and costly monitoring as defined in higher levels.1 For example, vessels that have not changed their ballast water are not likely to be able to use level I monitoring approaches to establish with confidence that the risk is acceptable. They would require level II or level III analyses—with some potential exceptions, as discussed previously. Thus, although "no action" is the least costly option for managing ballast water, this option would require extensive monitoring to establish 1    Such criteria may be sensitive to vessel type, voyage history, and other factors.

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that the ballast water meets acceptable levels of risk. In contrast, treating ballast water on board requires investment in equipment and crew training, as well as operational expenditures. However, the associated monitoring procedures would be simpler and could potentially be integrated with the treatment system to provide continuous feedback on treatment effectiveness. It is probably inevitable that ships taking on ballast water in estuaries will take on sediment. Monitoring approaches need to address the combination of water and sediment. Monitoring the sediment phase is discussed later in this chapter, following the discussion of monitoring water. Level I Monitoring Level I monitoring consists of (1) an examination of the ship's logs and records of where and how much ballast water was initially loaded and where and how much of it was changed, accompanied by (2) continuous monitoring of basic physical-chemical water quality parameters, such as turbidity, salinity, temperature, concentration of dissolved oxygen, and pH (see Table 5-2). These parameters can be monitored by automatic, online equipment that provides continuous readouts for subsequent data storage or for direct transmission to shore. Alternatively, all of these parameters could be measured concurrently by handheld equipment at regular intervals. TABLE 5-2 Basic Physical-Chemical Water Quality Parameters Indicator Definition Potential significance for ballast water monitoring Salinity Amount of dissolved salts in water (reported as parts per thousand sodium chloride or as specific gravity). Could indicate extent to which port water was changed with oceanic water. Turbidity Amount of light-reflecting material in suspension in water. Could indicate concentrations of plankton and suspended sediment. Temperature Degree of heat. The survival potential of ballasted organisms may be determined in part by (1) changes in temperature from voyage start to finish and (2) the temperature difference between ballast uptake and discharge ports. Dissolved oxygen Amount of oxygen dissolved in water. May indicate general ability of ballast water to support living organisms. pH Level of acidity or alkalinity in water, as measured by the negative logarithm of hydrogen ion activity. May indicate differences between port (estuarine) and oceanic water

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Records of ballast water operations are currently kept aboard the vast majority of vessels (Carlton et al., 1995). Thus, examination of ships' logs and records (containing mandatory information) for monitoring purposes would not impose any additional burden on the shipping industry, and it could be used in conjunction with basic water quality parameter measurements to verify that ballast had been changed prior to arrival at port. The basic parameters indicative of water quality are readily measured using commercially available instruments and test kits; reliable measurement of pH, conductivity, dissolved oxygen, and temperature is available using a single probe for analysis. Both microprocessor-controlled and digital instrumentation packages can be interfaced with a computer or data-logger for continuous analysis, and many commercial units have been field tested that are suitable for marine applications. Turbidity and concentrations of specific chemicals can also be analyzed using colorimetric and amperometric techniques. Instruments designed for use in process streams can provide continuous measurement of water quality parameters necessary for ballast treatment technologies. Most of these systems are priced between $500 and $2,500, excluding installation costs. Turbidity may currently be the most useful indirect indicator for establishing the presence of port or inshore water as opposed to open-ocean water; low turbidity would indicate the lack of dense biological populations, such as algal blooms. Measurements of turbidity also reflect relative concentrations of undesirable plankton and suspended sediment. Since it is likely that some sediment will be present at the bottom of the ballast tanks, the results of turbidity measurements can be greatly influenced by sampling location. Ships arriving from ports and harbors known to be active sites of infestation by known nuisance species may, in addition to the Level I monitoring outlined above, be sampled to check for the presence of the species in question. This would require impounding a vessel until its ballast water had been rigorously examined, unless a "sampling and dispatch" approach could be implemented. Level II Monitoring The presence of life in ballast water can be determined quickly by several techniques that assess bioactivity in the water. These techniques, many of which can now be automated, include measuring one or more of the following: Photosynthetic pigment. The amount of chlorophyll present in the water reflects the biomass of living phytoplankton in the water. ATP. The presence of a biochemical energy system, adenosine triphosphate, indicates that living cells are present. Nutrients. The amount of a compound such as nitrate or phosphate in the water indicates that level of nutrients available to support phytoplankton. Another technique is to determine the presence and abundance of one or more particular species (such as a bacterium or dinoflagellate) known as indicator

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species. The potential presence of additional, similar species can then be inferred without actually undertaking a more extensive biological analysis. This indicator species approach is used in waste-water treatment, where certain organisms (e.g., enteric bacteria) are used as surrogates to predict the presence of pathogens in waste water, including bacteria, viruses, protozoans, nematodes, and flatworms. Although the indicator species approach may not be useful for monitoring ballast water in all cases, it may be useful in specific instances. For instance, if ballast water had been taken up in an area known to harbor an unwanted species, that particular species might be searched for specifically. Particularly resistant forms known to present high risks (such as dinoflagellate cysts) might be selected for monitoring. At the same time, it could be assumed that, if a particular species were killed or removed, most other species would also be eliminated. Level III Monitoring Advanced biological analysis comprises collecting plankton samples from the water column and benthic samples from bottom sediment (if present), followed by taxonomic identification to the species level, if possible. Identification may be manual or flow cytometry, molecular probes, or immunofluorescence may be used (see Appendix H). Level III monitoring with existing technology is probably not feasible except when the risk of introduction is very high. In particular, the time needed for advanced biological analyses is not compatible with shipping schedules. However, the development of automated techniques, such as immunofluorescence, may eventually allow onboard identification of specific taxonomic groups. A number of biochemical methods for monitoring water are currently under development and might be applicable to level II and level III monitoring in the longer term (see Appendix H). MONITORING AFTER TREATMENT OF BALLAST WATER In contrast to the generic approaches to ballast water monitoring described above, monitoring methods after ballast water has been treated on board may be closely tied to the method used to treat the ballast water. For example, it may be possible to monitor the effectiveness of biocide treatments by monitoring the presence and concentrations of residuals in ballast water. Australian researchers have identified three steps needed when monitoring the treatment of ballast water on board ships (AQIS, 1993): Record equipment operation to confirm that all ballast water has been appropriately treated. Sample treated ballast water and sediment to check performance of the equipment.

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Perform random inspections of facilities to ensure that they are properly maintained and operated. The present discussion focuses on the second step for the three most promising treatment categories identified in Chapter 4—biocidal (chemical) treatments, filtration (mechanical) systems, and thermal (physical) treatments. The effectiveness of treating ballast water with a chemical biocide could be monitored by measuring the amount of biocide (residual) in the water, rather than the organisms. For example, in wastewater disinfection, where chlorine is the most common biocide, the residual levels of free chlorine are routinely measured by various colorimetric or titrimetric methods. Because of environmental concerns about chlorine, the U.S. Environmental Protection Agency (EPA) has placed limitations on the discharge of free residual chlorine. From an environmental point of view, a desirable ballast water biocide would be one that quickly degrades into nontoxic byproducts and does not pose a chemical threat to the receiving environment.2 However, this could make monitoring for the residual biocide itself more complicated. Monitoring for turbidity after filtration may be a reasonable technique to assure the effectiveness of the filtration process. Turbidity indicates that there are particles in the water, some of which may be living organisms.3 Low turbidity would indicate a lack of dense biological populations. High turbidity could indicate concentrations of plankton and suspended sediment. In the case of thermal treatment, the success of treatment would need to be measured in terms of the degree of completion of the inactivation process. In laboratory tests, the effect of heat treatment on toxic dinoflagellate cysts was determined by observing germination rates when culture medium was added to the treated sample (Bolch and Hallegraeff, 1993). Clearly such an approach—which is not applicable to all organisms—would not be practical for shipboard use, and development of a simple, onboard test method is needed to support the heat treatment option for treating ballast water. It would also be possible to monitor temperature versus treatment time as an indicator of effective treatment. SAMPLING ISSUES There are a number of sampling issues associated with using level II or level III monitoring to establish the presence of living organisms in ballast water. Certain species of plankton migrate vertically in the water column, going up at night and down during the day; this behavior may continue for several days in the absence of light cues. Further, ballast water samples taken during the day in 2    A discussion of discharges to the environment following ballast water treatment is given in Chapter 4. 3    The use of particle size analysis as a monitoring tool may merit consideration in some situations.

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cargo holds whose hatch covers have been opened (and thus the water fully exposed to daylight) may not reveal planktonic species that have descended to the tank bottom. Alternatively, ballast tanks that are suddenly exposed to a light source (for example by removing a deck manhole cover on a topside tank) may cause certain species to be attracted to the light, and their density may be artificially increased. When feasible, ballast water should be sampled at various depths and as deep as possible, and inline sampling should be used when filling ballast tanks, if possible. MONITORING SEDIMENT Ballast sediment at tank and hold bottoms requires periodic monitoring to understand its influence on turbidity readings and nutrient levels and its potential to act as a sink and source of transported organisms. Four methods are available for sediment sampling and monitoring (AQIS, 1992): In-line turbidity meter. The turbidity of outflow water (whose turbidity has been premeasured at different vertical levels in the tank) could be measured. Comparing elevated turbidity readings of outflow water with turbidity readings of the tank's water column could indicate input from bottom sediment. However, a determination that sediment is being discharged comes too late to permit remedial action. Monitoring the turbidity of incoming ballast water forewarns the ship's master that sediment is present and that changing or treating ballast water will probably be required prior to arrival at port and deballasting. Suspended sediment sampling at ballast load port. Representative sediment samples could be taken by lowering sampling devices through deck-level access openings. This method could be used to obtain water column samples during or just after ballasting, when the bottom sediment is still suspended in the water column and has not settled to the bottom of the tank. Direct observation and sampling via tank access. Tank bottoms are typically inspected for their sediment loads by entering an empty tank and examining the amount of sediment present. Again, a determination that sediment is present comes too late to permit remedial action to control the discharge of suspended sediment in the ballast water. Sediment sampling at ballast load port. Samples of harbor-bottom sediment could be taken at the ballast water loading port adjacent to the cargo discharge berths as an indicator of the sediment content of ballast water. If either of the last two methods were used, sediment samples could be taken to determine the presence of living organisms, such as dinoflagellate cysts and benthic invertebrates.

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SETTING STANDARDS Cost-effective implementation of the monitoring approaches described in this chapter requires (1) the development of monitoring technologies with the necessary sensitivity and (2) the determination of appropriate standards. As noted in Chapter 3, identifying risk-based levels of protection—and developing associated standards—depends on both biological data (assessing the probability of establishment) and social judgements regarding potential risks (assessing the consequences of establishment) (see Box 3-3). Assessment of the consequences of introductions of nonindigenous aquatic species is beyond the scope of the present study. However, the committee considered some brief remarks on the challenges of setting standards to be appropriate in the context of the preceding discussion of monitoring. The ability of biological science to predict the probability of establishment of nonindigenous aquatic species is currently very limited. As noted earlier, it is not known how many individuals of a given species, or their densities, are needed to establish a viable, self-reproducing population at a new site. Even if this number were known, it would not be consistent from one receiving environment to another. It is daunting to contemplate the amount of research that would be required to adequately assess all of the organisms that could possibly be established in new locations. The use of risk assessment to establish safe levels of exposure to carcinogens and other toxic chemicals provides an interesting analogy. In setting such standards, two different approaches are used. In one approach, toxicological data on individual chemicals are used to estimate the dose of a carcinogen that would result in a one-in-a-million risk of cancer. While limited, these toxicological data are generally far more extensive than current information on how many individuals need to be released in a new environment to establish a viable population of a given species. Alternatively, standards for controlling water pollution are sometimes based on levels of contaminants that can be achieved after treating water with the ''best available technology." It remains to be seen to what extent such approaches can be used in setting standards for discharge of ballast water. Regardless of how standards for the safe release of ballast water are determined, it is important that the supporting reasons and assumptions be fully transparent to all those affected. In addition, the implementation of ballast water controls based on the standards should be accompanied by appropriate outreach, education and training activities. REFERENCES AQIS. 1992. Controls on the Discharge of Ballast Water and Sediment from Ships Entering Australia from Overseas. Australian Quarantine and Inspection Service Notice. Canberra, Australia: Australian Government Publishing Service.

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AQIS. 1993. Ballast Water Treatment for the Removal of Marine Organisms. Report No. 1 in Ballast Water Research Series. Canberra, Australia: Australian Government Publishing Service. Bolch, C.J., and G.M. Hallegraeff. 1993. Chemical and physical treatment options to kill toxic dinoflagellate cysts in ships' ballast water. Journal of Marine Environmental Engineering1:23–29. Carlton, J.T., D.M. Reid, and H. van Leeuwen. 1995. The Role of Shipping in the Introduction of Nonindigenous Aquatic Organisms to the Coastal Waters of the United States (other than the Great Lakes) and an Analysis of Control Options. Washington, D.C.: U.S. Coast Guard and U.S. Department of Transportation, National Sea Grant College Program/Connecticut Sea Grant. USCG Report Number CG-D-11-95. NTIS Report Number AD-A294809. Kerr, S.1994. Status of Australian Ballast Water Research: Project 10—Port Water Sampling Program (Established Organisms Baseline Studies). Canberra, Australia: Bureau of Resource Sciences.