I:\MEPC\57\2-3.doc

For reasons of economy, this document is printed in a limited number. Delegates are kindly asked to bring their copies to meetings and not to request additional copies.

INTERNATIONAL MARITIME ORGANIZATION

IMO

E

MARINE ENVIRONMENT PROTECTION

COMMITTEE

57th session

Agenda item 2

MEPC 57/2/3

7 September 2007

Original: ENGLISH

HARMFUL AQUATIC ORGANISMS IN BALLAST WATER

Application for Final Approval of a ballast water management system

using Active Substances

Submitted by Germany

SUMMARY

Executive summary: This document contains an application for Final Approval of a ballast

water management system under the Procedure for approval of ballast

water management systems that make use of Active Substances (G9)

adopted by resolution MEPC.126(53)

Action to be taken: Paragraph 5

Related documents: BWM/CONF/36; MEPC 53/24/Add.1; MEPC 55/23 and

BWM.2/Circ.10

1 Regulation D-3.2 of the International Convention for the Control and Management of

Shipsí Ballast Water and Sediments stipulates that ballast water management systems that make

use of Active Substances to comply with the Convention shall be approved by the Organization.

2 Germany herewith submits an application for Final Approval according to the Procedure

for approval of ballast water management systems that make use of Active Substances (G9). This Procedure stipulates the required information (MEPC 53/24/Add.1, annex 4, paragraph 4.2.1), which according to section 6, should be evaluated by the Organization. In

accordance with BWM.2/Circ.10, this document at the annex, contains the non-confidential part

of the manufacturerís application dossier. The complete dossier will be made available to the

experts of the GESAMP-BWWG with the understanding of confidential treatment.

3 Basic Approval of the Active Substances used has already been granted at MEPC 55

(MEPC 55/23, paragraph 2.16) and the competent authority took into account all the

recommendations contained in paragraph 10.4 of annex 7 of the Report of the second meeting of

the GESAMP-BWWG (MEPC 55/2/16).

4 The receiving competent authority in Germany has verified the application dossier and

believes it to satisfy the data requirements of the Procedure (G9) adopted by resolution

MEPC.126(53).
MEPC 57/2/3 - 2 -

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Action requested of the Committee

5 The Committee is invited to consider the proposal for approval and decide as appropriate.

***
MEPC 57/2/3

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ANNEX

PROPOSAL FOR APPROVAL OF RWO BALLAST WATER MANAGEMENT SYSTEM

ñ CleanBallast!

1 INTRODUCTION

The applicant is proposing a combined system using a mechanical separation step (disc filtration)

and an electrochemical treatment step (EctoSysÆ, receiving Basic Approval at MEPC 55) as a

complete solution for ballast water treatment. This complete ballast water treatment system was

described as Technology No. 1 in annex 1 of MEPC 55/2/17 and of MEPC 56/2/10 and will be

commercialized under the name of CleanBallast! Having defined and described the Active

Substances and Relevant Chemicals, which are produced in-situ by the electrochemical treatment

unit, previously under the Basic Approval procedure, the applicant hereby proposes the complete

CleanBallast! ballast water treatment solution to receive Final Approval under the Procedure (G9)

by resolution MEPC.126(53).

The application for Final Approval consists of two parts: an application dossier and a summary

document. The latter is also submitted by the Member directly to the MEPC. Besides covering

the requirements of the Procedure (G9), the application also includes data and argumentation

meeting the recommendations and requests given by the GESAMP-BWWG in their second

report recommending Basic Approval to be given to the disinfection unit (EctoSysÆ).

1.1 Description of the CleanBallast! system and its components

The CleanBallast! ballast water treatment system consists of one mechanical separation step and

one electrochemical treatment (disinfection) step. The Active Substances are exclusively

produced in-situ by the electrochemical treatment cell (EctoSysÆ). During ballast water uptake

the CleanBallast! system is operated inline using disc filtration followed by the EctoSysÆ

disinfection before the water enters the ballast water tanks. In general, re-growth of organisms is

possible in the ballast water tanks during the voyage, which is simulated during the land-based

type approval procedure by the five daysí tank storage. For prevention, the filter unit is bypassed

and, therefore, the EctoSysÆdisinfection alone is applied a second time during deballasting

before discharge.

As the first treatment step, the ballast water disc filter unit bases on the disc filter technology, which is already in use for filtering sea water on board ships for many years. The automatic disc

filter unit removes suspended solids, sediments and larger organisms and prevents the sediment

accumulation in the ballast water tanks. With nominal filter fineness of 50 μm, the disc elements

provide advanced filtration results by adding the in-depth filtration effect to the common surface

filtration.

For the 500 m3/h CleanBallast! system four filter housings are operated in parallel. The

differential pressure of the filter unit is used for the backwashing release. Hereby, one filter

housing after the others is backflushed automatically while the other ones handle the full flow

without interruption of the filtering process. The backflushing water, which contains the removed

particles of the source water, is discharged right back to the source water during ballast water

uptake.

The cleaned filtrate leaving the disc filters is subsequently treated by the inline advanced

EctoSysÆelectrolysis directly in the ballast water pipe, whereby the numbers of viable organisms

is minimized without any dosing of chemicals before entering the ballast water tanks. By
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applying a direct current between the anodes and cathodes, different disinfectants e.g., reactive

free hydroxyl- and oxygen radicals and a low amount of HOCl (will be converted to HOBr in

water with high salinity) are produced by EctoSysÆelectrolysis directly from the water due to an

effective mass transport (see further the separate application for Basic Approval, MEPC 55/2/4

and specific patent application HÂkansson, Bo et. al. ìElectrolytic cell for treating contaminated

watersî, WO2005058761(A1)). The simultaneous inline production of different disinfectants

gives the EctoSysÆa broad effectiveness range, and is the reason why relative low disinfectant

concentrations of 1 - 2 mg/l Total Residual Oxidants (TRO) are sufficient. Due to overpotential,

the advanced EctoSysÆelectrolysis can be operated likewise in river water without loss of

disinfection efficiency and therefore, in contrast to conventional chlorine electrolysis, no addition

of salt or brine solution is necessary in water with lower conductivity.

An additional feature of the CleanBallast! system is the so-called algae monitor, by which the

remaining number of viable phytoplankton is monitored continuously in the effluent of the

system and the efficiency of the disinfection can be controlled in real-time. For this land-based

type approval tests, the algae monitor was not controlling the EctoSysÆdisinfection and instead

the EctoSysÆwas run at maximum disinfection efficiency. This worst-case approach was chosen

in order to have the maximum disinfectants concentration in the test programme for the

Final Approval, which was run in parallel to the land-based type approval. As requested in

Guidelines (G8), part 4, paragraph 4.4 for sharing information on new approaches for monitoring

viable organisms, it is envisaged to provide information on the algae monitor to the German

Administration for further submission to the MEPC if it deems appropriate. Furthermore, it was

recommended by the GESAMP-BWWG that sensors etc. should monitor the production

of Active Substances in order to minimize concentrations (MEPC 55/2/16, annex 7, paragraph 3.1.2), hence is the algae monitor providing an effective way to approach this

recommendation indirectly by monitoring the effect of the disinfection online on viable

phytoplankton and give feed-back data to the EctoSysÆfor adjusting the disinfection efficiency.

The CleanBallast! system is fully automatically controlled by a PLC (Programmable Logic

Controller) and automatically operated including power control when all conditions for each

operation mode are available. Hereby, the operation sequence is displayed on the screen and

status messages and alarms are generated as well as the required data recorded and stored.

1.2 Description of the test facility used in the simultaneous land-based type approval

and Final Approval test procedures

The test facility is installed on a commercial barge which has a length of 45 m, a width of 18 m, a

height of 3.30 m and a draught of 2.40 m. In total there are 12 ballast tanks. Three ballast tanks

have a capacity of 270 m3 each and two of them are used as control and treatment tank during the

type approval procedure. As a commercial barge the ballast water tanks have the normal internal

structures including air pipes and are coated with standard tank coating as it is the common

practice on board.

The piping material for the accrediting part of the plant is the common material for ballast water

piping (St37-2, zinc plated). The piping material for the external components on the barge is

plastic (PE). The control and the treatment line (each 500 m3/h) are equipped with sampling ports

with usual undisturbed straight main piping in front and afterwards. Its design guarantees that a

homogenous sample is taken reproducibly from the main line, which is especially important for

lighter particles such as algae. The sample ports are arranged according to Revised Guidelines

and specification for pollution prevention equipment for machinery space bilge of ship adopted
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by resolution MEPC.107(49), by which a homogenous sampling of lighter oil droplets is assured

since several years.

Fig. 1 and 2 show the process and sampling diagram for the ballasting as well as for the

deballasting procedure.

Fig. 1: CleanBallast! process and sampling diagram for ballasting procedure (sampling points in black circles)

Fig. 2: CleanBallast! process and sampling diagram for deballasting procedure after five days of tank storage

(Sampling points in black circles)

In addition to the biological sampling points shown in Fig. 2 during deballasting for some

parameters, samples where also taken after the treatment tank/feed pump and before the

C

EctoSysÆ

Treatment

line

E

Reference line

Feed

pumps

Treatment

tank

270 m

3

Control

tank

270 m

3

Discharge Discharge

A

B

Habour water F

4 parallel filters

EctoSysÆ

Treatment

line

D

Control line

Dosing of test

organisms Feed

pumps

Treatment

tank

270 m

3

Control

tank

270 m

3
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EctoSysÆvia sampling port A (DB) (not shown in Fig. 2) in order to see if a parameter changed

during the five daysí tank storage.

The ballast water treatment system and the testing arrangement have been technically examined

and commented by the Germanischer Lloyd (GL). The test facility and testing procedure were

accepted by the German Administration BSH to be in compliance with Guidelines (G8).

Guidelines (G8) require tests to be performed in two salinities. The first test set was accordingly

run in brackish water (11-15 psu depending on the tide) in the Kaiserhafen/Bremerhaven

(Germany) and the second test set in river water (< 3 psu) in the Industriehafen/Bremen

(Germany).

1.3 Performance according to the D-2 standard

Guidelines (G8) state that the Ballast Water Performance Standard (D-2) shall be fulfilled during

the land-based type approval process. This performance standard states, e.g., that ships shall

discharge less than 10 viable organisms  50 μm in minimum size per m3 and less than 10 viable

organisms  10 μm and < 50 μm in minimum size per ml.

The whole effluent characterization and toxicity studies related to the land-based type approval

tests were performed at conditions fulfilling all performance requirements of the D-2 standard, and all other additional requirements of the Guidelines (G8), e.g., the inlet and outlet criteria

(G8, annex, paragraph 2.3.16). The type approval documentation in form of analysis reports will

be submitted to the GESAMP-BWWG.

1.4 Biocidal Products Directive

The use of ìActive Substancesî by the disinfection electrochemical system (EctoSysÆ) refers to

the descriptions and definitions given in Procedure (G9) and does not fall under the

Directive 98/8/EC (the Biocidal Products Directive, BPD) of the European Parliament and of the

Council of 16 February 1998 concerning ìActive Substancesî to be placed on the market. Further

information is given in the previous application for Basic Approval (MEPC 55/2/4).

2 DEFINITIONS

ìBallast Water Dischargeî refers to water, fresh- brackish or full salinity, having been treated by

the CleanBallast! ballast water treatment process according to the description given in section 1.1.

ìLand-based type approval (or LBTA) test set-upî refers to the applicants test facility and

equipment used in the type approval procedure according to Guidelines (G8) described further in

section 1.2.

The terms ìActive Substancesî, ìRelevant Chemicalsî and ìPreparationsî used in this

application refers to the definition given in the Procedure (G9).
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3 APPLICATION FOR FINAL APPROVAL

3.1 General approach on information gathering for the risk assessment

The approach of the applicant carrying out the tests has been focused on generally taking a

worst-case approach in every test, assessment and evaluation of achieved data. Reliable safety

factors (recommended by the GESAMP-BWWG) have been applied. Because of the

physical/chemical variety and complexity of natural waters, in which the CleanBallast! is

intended to operate, as well as due to the inline in-situ production of different oxidants

simultaneously by the EctoSysÆwhole-effluent tests have generally been used (i.e.,, for toxicity

tests, chemical analysis, corrosion study and discharge computer modelling).

The tests included in the Final Approval procedure are done in parallel to the land-based type

approval procedure, in accordance with the Procedure (G9). Studies have shown that the

CleanBallast! system always fulfils performance and other requirements at initial (directly after

the advanced electrochemical treatment step) concentrations of 2 mg/l Total Residual Oxidants

(TRO) or below in the discharge water. Thus, an approximate value of 2 mg/l initial

TRO concentration has been used as the worst-case concentration throughout the tests for

Final Approval. However, it is noted that the main disinfection/oxidative function of the

electrochemical advanced oxidation process (EAOP) of the EctoSysÆtechnology occurs within

the reactor, using the indirect oxidation from produced hydroxyl radicals and direct oxidation at

the anode surface. Therefore the TRO concentration in the effluent should be interpreted as an

indicator of the level of disinfection, and not as the means to achieve such disinfection levels.

3.2 General considerations on available data

Due to the fact that the proposed electrochemical disinfection system (EctoSysÆ) is not based on

the supply or addition of any chemicals to the water to be treated, it was concluded in the

application for Basic Approval that the guidance provided in the Procedure (G9) regarding the

testing and characterization of the Active Substances was not applicable at all points. Furthermore, one of the Active Substances (i.e., hydroxyl radicals) in question has such a short

half-life that it is not possible to characterize it from the point of view of persistency, bioaccumulation, endocrine disruption etc. which is a major part of the Procedure (G9). The main

disinfecting effect of the hydroxyl radicals produced will take place inside the electrochemical

system itself (within a few micrometers from the electrodes), and will not (beside some residual

regrowth preventing effect originating from active chlorine and/or bromine species) occur in

other parts of the ballast water system either on the ship or after discharge of the ballast water

back to the harbour/sea.

It will be shown by the data given in this application that in fresh water, e.g., river water

harbours, hydroxyl radicals are the only Active Substance formed in the CleanBallast! process. The reason is that due to the low salinity and subsequently chloride concentration in said waters,

the Active Substance of free active chlorine can not be formed in relevant concentrations by the

EctoSysÆelectrochemical advanced oxidation process. Furthermore, Relevant Chemicals such as

chlorinated/brominated disinfection by-products will likewise not be formed in low salinity

waters.

Toxicity data on whole-effluents from the electrochemical treatment system alone, reported in

the application material for Basic Approval, gives the collected picture of the toxicity in effluent

waters at a certain time after treatment. In both cases of EctoSysÆand the complete CleanBallast!
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effluents, the Total Residual Oxidant (TRO) is judged to be the primary cause of acute toxicity or

precursors for by-produced toxic species. This assumption was supported by the

GESAMP-BWWG in the evaluation (MEPC 55/2/16, annex 7, paragraphs 9.2.2 and 10.3.3) of

the application for Basic Approval (MEPC 55/2/4), comparing the toxicity data with the ones of

active chlorine. The assumption that the acute and chronic toxicity of the treated water is

proportional to the TRO concentration has been further studied and confirmed during the

Final Approval procedure. This has been investigated using simultaneous on-site kinetic ekotox

technique, on-site standard toxicity tests on samples collected directly after treatment, and at the

same time monitoring the degradation of the TRO level (which is very rapid in natural waters). Further description and results are reported under section 3.7.1. These acute studies have been

complemented with tests on stored samples, confirming that no further toxic substances form

over time in the treated water.

Thus, it is considered clarified that the residual toxicity of treated water is at its highest level

initially, directly after treatment by the electrochemical disinfection unit, and that it is

proportionally linked to the TRO concentration. Studies show that TRO levels of this magnitude, produced by the CleanBallast! system, in natural sea and brackish waters degrade readily back to

back-ground levels during the first 20 ñ 150 min. after treatment, leaving no or very low levels

(comparable to drinking water standards) of residual secondary by-products (see section 3.5.2.1). As mentioned above, in fresh waters e.g., river water, increased TRO levels in the effluent of the

EctoSysÆwill be very limited initially and over time, because pre-dominantly the very

short-lived hydroxyl radicals are formed and decay directly in the electrolytic cell during the

actual disinfection process.

3.3 Identification (G9, 4.1)

The electrochemical treatment (EctoSysÆ) used as the disinfection step in the CleanBallast!

treatment solution generates the Active Substances in-situ in the ballast water stream without

adding any precursors, active or non-active, to the water. No commercial formulation, including

additives, is added to the CleanBallast! system in order to comply with the D-2 standard .

The highly oxidative Active Substance primarily produced by EctoSysÆin natural waters such as

seawater/brackish water is the hydroxyl radical, OHï. This species under normal circumstances

has a half-life in the order of nanoseconds, and thus never leaves the cell (or the reaction zone)

with the water flow. The hydroxyl radical very efficiently inactivates and breaks down

micro-organisms and other contaminants. No chemically active long-lived residuals are formed at

relevant concentrations in this process using this electrochemical treatment method and specially

developed electrochemical cell. Indirect disinfection and also direct oxidation of

micro-organisms on the electrodes will only contribute to the Total Organic Carbon (TOC) level

(MEPC 55/2/4). The Active Substances and Relevant Chemicals that can be produced by the

electrochemical reactor at detectable concentrations are, hence, identified according to the

following:

 Hydroxyl radical, OHï: a very reactive oxidative species with half-life in the order of

nanoseconds, thus never leaving the reactor. Secondary radicals may also be formed in

very small amounts as intermediates in the degradation processes of other oxidative

species. The hydroxyl radical will be referred to as an ìActive Substanceî of this

electrochemical disinfection method.

 Free Active Chlorine: due to the sea water content of chloride ions, small amounts of

chlorine gas (Cl2) will form as a by-product on the anode surface and will further, by
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favourable interactions with the cathode due to the electrochemical cell design,

immediately dissolve and form non-volatile HOCl and/or OCl

- depending on the pH. Cl2

gas (in amounts relevant) cannot exist in water solutions without undergoing this

transformation, and thus not either evaporates from the treated water. The interaction with

the cathode surfaces also prevents the formation of harmful chlorinated organics such as

e.g., trihalomethanes (THM). The small amounts of free active chlorine will contribute to

prevent regrowth/biofouling in the ballast tanks and after interactions with species present

in natural waters ultimately degrade back into chloride ions. Free active chlorine will be

referred to as ìActive Substanceî due to their oxidative and disinfecting abilities.

 Hydrogen gas, H2(g): will be formed at the cathode due to common water electrolysis ñ

however, due to the composition of the electrochemical cell, the main cathode reactions

will be reduction of oxygen gas (O2), reduction of Total Residual Oxidants (TRO) and

formed Disinfection By-Products (DBP). Hydrogen gas will be referred to as a ìRelevant

Chemicalî in this application due to the safety aspects of this gas.

ìRelevant Chemicalsî will also include the potential disinfection by-products (DBPs) resulting

from an electrochemical treatment of natural waters. Focus was laid on potential DBPs formed in

waters with higher salinity, because concerns have been raised especially over chlorinated

organics. Thorough analysis on full-scale whole-effluents as well as worst-case analysis in

laboratory scale was done. See further section 3.5.2.1.

3.4 Total Residual Oxidants

Throughout this document, the term Total Residual Oxidants (TRO) will be used referring to the

measurable quantity of oxidants resulting from the electrochemical treatment process. The TRO

concentration is analysed using the standard manual DPD-reagent technique for analysis of Free

and Total Active Chlorine (FAC and TAC), well-known to be non-selective to species included

in those groups but measures all oxidative species above a certain oxidation potential present in

the water. The oxidants formed in the EctoSysÆelectrochemical cell will, due to the different

features (see separate application for Basic Approval, MEPC 55/2/4) in contrast to conventional

chlorine electrolysis, where only free active chlorine is formed, consist of a mixture of such

oxidants. Due to the complexity and diversity of natural waters, all these individual short-lived

oxidants are not possible to analyse qualitatively or quantitatively. Furthermore, the degradation

back to the background reading for TRO will be too rapid to conduct analysis required for such

quantification. Free Active Chlorine is recognized as Active Substance since it will be these

species immediately forming from the initially formed Cl2 at the anode during electrolysis of

chloride containing waters. Sea water equilibrium, however, for instance will favour active

bromine to be predominant over time. Both chlorine and bromine are detected together with other

oxidant as TRO during analysis. Therefore, a differentiation between the different species

measured as TRO is not possible.

Throughout the tests performed and included in this application for Final Approval, an

approximate initial TRO concentration of 2 mg/l has been used as the worst-case concentration. Verification for this approach is described under section 3.1.
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3.5 Data-set for Active Substances and Relevant Chemicals (G9, 4.2)

3.5.1 Active Substances

A proposal for approval should include information on the properties or actions of the

Preparation or any of its components. In the case of Active Substances used by the CleanBallast!

system, this information is included and have been submitted in the application for Basic

Approval.

3.5.2 Relevant Chemicals

The GESAMP-BWWG recommended more detailed information on Relevant Chemicals before

Final Approval can be granted to any ballast water treatment system including the advanced

electrochemical treatment system EctoSysÆ(MEPC 55/2/16, annex 7, paragraph 7.2.2). Relevant

Chemicals are recognized as potential disinfection by-products and hydrogen gas formed at the

cathode.

3.5.2.1 Disinfection by-products

In general, hydroxyl radicals do not serve as precursors for halogenated disinfection by-products

(DBPs) when participating in oxidation/reduction reactions with natural organic material. However, in the presence of bromide present in raw water, any oxidizing disinfection might lead

to the formation of other DBPs, e.g., bromate similar to Ozone decomposition mechanisms. By studies in artificial bromide-containing solution, von Gunten and Oliveras (1998) showed that

bromate can be formed by a pure OH radical mechanism and that hypobromous

acid/hypobromite is a requisite intermediate in bromate formation.

Active chlorine can act as precursor for DBPs. The formation of active chlorine in

electrochemical treatment processes is always closely linked to the chloride concentration of the

electrolyte (= the natural water) and, assuming no other controlling of the reaction rate, the

highest levels should be expected in waters with the highest chloride content (i.e., full salinity sea

water). In turn, the level of halogenated by-products will be formed in proportion to the active

chlorine/bromine in specific natural waters.

It is known that the conventional chlorination of water containing bromide and natural organic

matter (NOM) leads to the formation of halogenated organic compounds, such as brominated

trihalomethanes and haloacetic acids. Bromine substitution in disinfection by-products formed is

a consequence of the rapid oxidation of bromide by chlorine to bromine, whereby in seawater

at pH 8 hypobromous acid (HOBr) is the decisive species. This reaction is fast and may have

reached completion within 2.5 min. after chlorination of seawater (Wong and Davidson 1977).

Hereby, the ratio of bromide ion to chlorine concentration affects the THM formation and

bromine substitution of chlorine. For chlorinated drinking water, Nokes et al. (1999) showed that

above a molar [Br

-]: [chlorine] ratio of 0.4 the brominated THM were the dominant fraction of

total THM (TTHM) and at very high [Br

-]: [chlorine] ratios, bromoform is virtually the only

THM present.

The competitive reaction between chlorine and ammonia can be neglected due to the low

ammonia level and the higher bromine concentration in the chlorinated harbour/seawater

(Allonier et al., 1999).
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In general, it is well proven that NOM is the principal precursor of DBP formation and that the

DBP concentrations are typically greatest in the summer and earlier fall (United States

EPA 1999; Allonier et al., 1999). Major reasons are that the DBP formation increases with

increasing temperature and the seasonally variation of NOM in kind and concentration. In this

regard, the conditions of the land-based type approval testing of the CleanBallast!, which was

carried out in the summer time, favour the formation of DBP and facilitate the worst-case

approach. However, analysis of by-product formation caused by the advanced electrochemical

disinfection treatment of the CleanBallast! system has been made in three natural waters with

different salinity (chloride content): full salinity sea water (35 psu), brackish water (11-15 psu)

and in fresh water (< 3 psu). Examples of drinking water regulations are mentioned here to serve

as comparative values in the complete risk assessment of by-products formation in CleanBallast!

treatment, knowing the worst-case concentrations of DBPs produced.

Adsorbable Organic halogens (AOX) is a measure of the number of C-Cl bonds formed in a

reaction, expressed as Cl2 consumed to form these bonds. Part of the AOX content is volatile;

the main representative in this case is chloroform. It is very important to distinguish between the

volatile and the non-volatile part in order to analyse the AOX. The non-volatile part is of high

importance due to the potential stability of some of the components (mainly the chloroacetic and

chloroaromatic compounds).

Trihalomethanes (THMs) are a group of (mainly) four chemicals that are formed along with other

disinfection by-products when chlorine or other disinfectants used to control microbial

contaminants in water react with naturally occurring organic and inorganic matter. The trihalomethanes are: chloroform, bromodichloromethane, dibromochloromethane and

bromoform. In general, trihalomethanes are suspected to damage the liver, kidneys and central

nervous system and are considered carcinogenic, but differences between the single THM species

exist. In the case of drinking water, different regulations are currently active internationally.

In the United States the standard was reduced from 100 to 80 Ïg/L in the ëStage 2 disinfectants

and disinfection by-products ruleí (EPA, 2006). The EPA standard replaced a standard of a

maximum allowable annual average level of 100 parts per billion, in December 2001, for large

surface water public water systems. The standard became effective for the first time in

December 2003 for small surface water and all ground water systems.

The WHO has a separate standard considering trihalomethanes (WHO, 2005):

Bromodichloromethane (CHBrCl2): 60 Ïg/l

Bromoform (CHBr3): 100 Ïg/l

Chloroform (CHCl3): 300 Ïg/l

The production of bromoform has been reported for several species of marine algae, e.g., marine

red, green and brown macroalgae. This formation is enhanced in the presence of stressors such as

mechanical stress, increase light or addition of hydrogen peroxide (Sundstrˆm et al. 1996). Furthermore, by-products of algae metabolisms are known to be the main precursor for an

increase in THM formation by the conventional chlorination of estuarine water. This was proved

by chlorination of algae culturing media after the removal of the algae population

(Crane et al. 1980).

Halogenic acetic acids (HAA) are an important type of chlorinated disinfection by-products. HAAs are suspected to favour the development of cancer. Acetic acids consist of three hydrogen

atoms that are fixed to a COOH-group. H-atoms of halogenic acetic acids are partly replaced by
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halogen atoms. HAA are hydrophilic non-volatile compounds. HAA can occasionally be found in

the water in higher concentrations than trihalomethanes (THM). This is determined by the

pH value of the water. Most literature indicates that when the pH value is lower, more HAA are

formed and when the pH value is higher, more THM are formed (Dalvi et al. 2000). The composition of naturally present organic matter (NOM) also determines the amount of

THM or HAA that is formed. Fabbricino (2005) found higher THM over HAA concentrations in

chlorinated coastal water, while in chlorinated deep ocean water the relative contribution of

HAAs was almost four times higher than that of THMs. In the United States, the EPA has

established a standard of 80 Ïg/L for five halogenic acetic acids (MCAA, DCAA, TCAA, MBAA and DBAA; EPA, 2006).

Bromate (BrO3

-) is an inorganic by-product, which formation is associated with Ozone when

Ozone used for disinfection reacts with naturally occurring bromide found in source water. Naturally, bromate can be formed by the disproportionation of hypobromite into bromate and

bromide, which is favoured at pH 7.3 and one possible pathway for the decomposition of

hypobromite (compare also above; Wong and Davidson 1977). Bromate is well known to be

carcinogenic and must be controlled at all sea water treatment with oxidative methods. The Stage 2 Disinfectants/Disinfection By-products Rule (EPA, 2006) regulates bromate at an

annual average of 10 μg/l in the case of drinking water.

3.5.2.1.1 THM and AOX

The GESAMP-BWWG raised concerns regarding unacceptable levels of THM and AOX

potentially being formed at residual chlorine levels of > 1 mg/l (MEPC 55/2/16, annex 7, paragraph 6.2). As expected at a [Br-]: [TRO] ratio of 16 or higher, THM formed in brackish and

sea water will ultimately to the most extent consist of bromoform (CHBr3). Examples of analysis

results from the total formation of THM and AOX in test waters during worst-case operation of

the CleanBallast! full-scale LBTA system within the type-approval process is summarized in

Table 1, which gives also the major chemical-physical water parameters as well as the biological

efficiency for the two larger size-classes regarding the D-2 standard .
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Table 1: THM formation in the test water during the LBTA process (test cycle 3)

at worst-case condition due to unusual EctoSysÆreversed polarity mode

both during ballasting and deballasting procedure

Ballasting procedure Initial TRO 1.6 mg/l

Parameter Unit Inlet treatment A

pH-value - 7.72

Practical salinity units psu 14.80

Oxygen (dissolved) mg/l 9.20

Total Suspended Solids (TSS) mg/l 100.67

Total Organic Carbon (TOC) mg/l C 35.63

Dissolved Organic Carbon (DOC) mg/l C 19.40

Particular Organic Carbon (POC) mg/l C 16.23

Ammonium (NH4) mg/l < 0.4

Deballasting procedure Initial TRO 1.6 mg/l

Parameter Unit After treatment tank A(DB) Effluent treatment C Effluent control E

pH-value - 7.1 7.1 7.1

Practical salinity units psu 13.4 13.9 14.5

Oxygen (dissolved) mg/l 6.0 7.5 3.8

Total Suspended Solids (TSS) mg/l 10.0 12.3 16.7

Total Organic Carbon (TOC) mg/l C 5.1 3.5 4.0

Dissolved Organic Carbon (DOC) mg/l C 1.6 2.9 2.6

Particular Organic Carbon (POC) mg/l C 3.5 0.6 1.4

Ammonium (NH4) mg/l 0.4 <0.4 0.4

Trichloromethane Cl3CH μg/l <0.3 <0.3 <0.3

Dichlorobromomethane CHBrCl2 μg/l 0.2 0.5 <0.1

Dibromochloromethane CHClBr2 μg/l 6.8 13.0 <0.1

Tribromomethane Br3CH μg/l 180.0 330.0 <0.1

Sum (TTHM) μg/l 190.0 340.0 0

AOX mg/l 0.08 0.16 0.07

Size ≥ 10 and < 50 μm Cells/ml 0 0 152

Size ≥ 50 μm Cells/m3 0 0 127,785

Hereby, it has to be stressed that the worst-case conditions were not only achieved by testing in

the summer time as mentioned above, where the highest DBP formation potential is known, and

at higher DOC levels than requested for the IMO test water during LBTA but also by operating

the EctoSysÆunder worst-case conditions in respect of DBP formation. In order to prevent

mineral hydroxide deposits from seawater on the cathode surface, the polarity of the electrodes is

reversed in certain time intervals. During normal operation (defined by HÂkansson, Bo et. al. ìElectrolytic cell for treating contaminated watersî, Patent application

no.: WO2005058761(A1)), the last electrode is working at cathodic potential reducing effectively

THM formed previously in the cell. At reversed polarity, the last electrode before the water

leaves the cell is working at anodic potential at which the applied current partly forms TRO. When the cell ends with an anode, the THM formed as disinfection by-product from anodically

produced TRO can not be further reduced at any cathodic surface. This result in higher THM

concentration compared to running the electrochemical cell with normal polarity. Due to

relatively frequent polarity reversal, the treated water originates from both normal and reversed

operation mode of the EctoSysÆresulting in a mean THM concentration during common

operation of the CleanBallast! system. In contrast, in the test cycle, which results are shown in

Table 1, the reversed mode alone was used during both the ballasting and deballasting procedure

and therefore presents the highest THM concentrations possibly produced and an unrealistic

worst-case due to normally applied reversal.
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These THM analyses represent the most far-reaching reaction in the treated effluent during

deballasting, because the TRO was not quenched after sample taking by adding sodium sulphite

or thiosulphate allowing the further THM formation. In reality, during discharging the treated

effluent, totally different secondary reactions might occur with the untreated harbour water, which might not result in the DBP formation.

It cannot finally be judged, if in comparison to the data of the Basic Approval the THM

formation was increased due to the higher concentration of metabolite by-products from

cultivating the algae, before dosing to the treatment and control line to guarantee the high inlet

cell numbers (above the natural population in the harbour water) required by Guidelines (G8). Literature data by Crane (1980) strongly indicate that metabolic by-products of algae may have a

major influence on the production rate of THM.

The biological data for the two size-classes in Table 1 show clearly that the D-2 standard was

already achieved by the ballasting treatment after the five daysí tank storage, because the

numbers of viable organism for both size-classes were zero at the sample port after the storage

tank before the water enters the EctoSysfor the second disinfection treatment during

deballasting. By using too much disinfection, this shows again the worst-case approach used in

these tests for the Final Approval and the usefulness of the abovementioned algae monitor for

controlling the disinfection efficiency online in real time as intended later. Hereby, it can be

prevented that the disinfection is used too much or too less and a response is possible to the great

variation in the water quality world-wide used as ballast water.

THM was also analysed in the test water used in the chronic toxicity studies. The natural full

salinity sea water with approximately 65 mg/l bromide was pre-filtered to 10 μm before

treatment. Filtering down to 10 μm removes more organic particles so that the oxidants present in

the water after disinfection will react more readily with the dissolved organics, favouring the

formation of DBP. The TRO concentration was kept at a constant level of approximate 2 mg/l, and thus, the levels of by-products found here can be considered as worst-case. The results are

summarized in Table 2.

Table 2: THM formation in full salinity test water used in the chronic toxicity studies)

Parameter Unit Full salinity (35 psu) TRO= 2 mg/l

Control Test water Trichloromethane Cl3CH μg/l <0.1 <0.1

Dichlorobromomethane CHBrCl2 μg/l <0.1 <0.1

Dibromochloromethane CHClBr2 μg/l <0.1 0.65

Tribromomethane Br3CH μg/l 0.58 33.8

Sum (TTHM) μg/l 0.58 34.45

3.5.2.1.2 HAA

The formation of haloacetic acids (HAA) was analysed both during the LBTA process and in

effluents used in the chronic toxicity studies. The results are summarized in Tables 3 and 4.
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Table 3: HAA formation in the test water during the LBTA process (test cycle 3; for

chemical, physical and biological parameters see Table 1)

Deballasting procedure Initial TRO 1.6 mg/l

Parameter Unit After treatment tank A(DB) Effluent treatment C Effluent control E

Monochloroacetic acid (MCAA) μg/l 0.14 0.57 <0.1

Dichloroacetic acid (DCAA) μg/l 0.12 0.26 <0.1

Trichloroacetic acid (TCAA) μg/l <0.05 0.06 0.08

Monobromoacetic acid (MBAA) μg/l 0.33 3.00 <0.1

Dibromoacetic acid (DBAA) μg/l 21.00 43.00 <0.1

Bromochloroacetic acid (BCAA) μg/l 0.66 1.60 <0.1

Table 4: HAA formation in full salinity test water used in the chronic toxicity studies

Parameter Unit Full salinity (35 psu) TRO= 2 mg/l

Control Test water

Monochloroacetic acid (MCAA) μg/l <1.0 <1.0

Dichloroacetic acid (DCAA) μg/l <1.0 <1.0

Trichloroacetic acid (TCAA) μg/l <1.0 1.5

Monobromoacetic acid (MBAA) μg/l <1.0 4.1

Dibromoacetic acid (DBAA) μg/l <1.0 12.2

Bromochloroacetic acid (BCAA) μg/l <1.0 1.9

As discussed previously for THM and known from the literature (e.g., Wu and Chadik, 1998), stronger bromine substitution occurs during HAA formation, because bromine is more reactive in

substitution reactions as well as the concentration of chlorinated HAA decreases as the bromide

concentration increases.

3.5.2.1.3 Bromate

The high chloride concentration of full-salinity sea water creates major interference problems

with analysing bromate at levels relevant in the case of CleanBallast! treatment. However, using

customized IC-ICP-MS technique, it is possible to reach reporting limits down to 10 μg/l in the

brackish water of Bremerhaven, where the first test set of the land-based type approval process

took place. Bromate was also analysed in the test water used in the chronic toxicity studies. The natural full-salinity sea water used was pre-filtered to 10 μm before EctoSysÆ

treatment. The results from both cases are summarized in Tables 5 and 6.

Table 5: Bromate formation in the test water during the LBTA process (test cycle 3; for

chemical, physical and biological parameters see Table 1)

Deballasting procedure Initial TRO 1.6 mg/l

Parameter Unit After treatment tank A(DB) Effluent treatment C Effluent control E

Bromate μg/l 27 66 <1
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Table 6: Bromate formation (highest measured) in full salinity test water used in the

chronic toxicity studies

Parameter Unit Full salinity water (35 psu) TRO= 2 mg/l

Control Test water

Bromate μg/l <1 18

3.5.2.1.4 Transformation processes and toxicity of disinfection by-products

In field side studies on artificial ground water recharge after chlorination, a rapid attenuation of

HAA was found (< 1 day) as well as a short half-life of < 1 - 9 day for bromoform, which is the

most rapidly attenuated THM. In contrast chloroform was the most persistent (mean half-life

of 65 days). This verifies the previously found persistence declining with increased bromination

of THMs (Pavelic et al. 2005).

Acute toxicity data of four trihalomethanes on rats have been investigated (Chu et. al. 1980). The

LD50 values were found to be between 848 and 1388 mg/kg. Bromoform seemed to be the least

toxic compound. The data on chloroform clearly demonstrate a non-genotoxic mechanism of

action and new data on the brominated THMs provide evidence that these too are of low

genotoxic potency, or are non-genotoxic in vivo (Fawell, 2000). Nokes et al. (1999) shows that

the total cancer risks due to THMs in chlorinated drinking water increases very rapidly as the

molar [Br

-] : [chlorine] ratio increases to approximately 0.15, after which the risk slowly

decreases to the value associated with bromoform alone at high [Br

-] : [chlorine] ratios of one

and higher. For comparison in brackish water of 14 psu treated by the CleanBallast! system the

molar [Br

-] : [TRO] ratio of 16 is very high (molar TRO assumed theoretically to be purely

chlorine). Batterman et. al. (2002) studied partition coefficients for the trihalomethanes in body

fluids, and reported that in humans, THMs are both stored and metabolized with relatively rapid

clearance rates.

The good biodegradability of DCAA, which has the third highest effluent concentration of

HAAs, is known in the literature from studies in wastewater treatment plants (Rodriguez et al., in

press). Similar fast biodegradation can be assumed for MCAA, because lower halogen

substituted are normally better biodegradable. Degradation products of HAA are carbon dioxide

and halide ions. Hanson et. al. (2004, I&II) have made toxicity studies on HAAs and also an

ecological risk assessments in aquatic environments. Exposure of three aquatic plant species

(Myriophyllum, L. gibba) to the different HAAs found low toxicity in the mg/l range (i.e., EC10)

and in the g/l range for higher effect levels (i.e., EC50). MCAA was generally the most toxic. HAAs were not considered to exhibit high degree of toxicity to Myriophyllum or L. gibba under

laboratory conditions.

A critical literature review has been undertaken of the effects that bromate (BrO3

-) has on aquatic

organisms (Hutchinson et al. 1997). Chronic (multigeneration) studies using four marine

phytoplankton species indicate a stimulation of cell division at concentrations up

to 13.6 mg/l BrO3

-, such that the EC50 is >13.6 mg/l BrO3- (exposure period unspecified). For freshwater invertebrates, the available data are limited to acute studies using two species: the

water flea, Daphnia magna, with a 48 h LC50 of 179 mg/l BrO3

-. For saltwater crustaceans, the

lowest reported acute value is a 24 h LC50 of 176 mg/l BrO3

- for mysid shrimp. Reported 96 h LC50 values for juvenile saltwater fish range from 427 to 512 mg/l BrO3

-.. For fish
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early life stages, newly hatched larvae are more sensitive than embryo hatching, with a

larval 96 h LC50 of 31 mg/l BrO3

- being observed. In conclusion, a number of studies provide

evidence for the acute toxicity of bromate to invertebrates and fish in the lowest region

of 30 mg/l BrO3

-.

Applying the factor of 10 used to extrapolate from acute to potential chronic toxicity, the

available data suggest that to protect aquatic organisms from long-term adverse effects, concentrations should not exceed approximately 3.0 mg/l BrO3

- (Hutchinson et al. 1997).

3.5.2.1.5 Summary and conclusions ñ Disinfection by-products

Analysis of treated ballast water effluents shows that the disinfection by-products of concern can

only be formed in water with higher salinity (not river water) and in this case will be in the range

of drinking water standards. Theoretical studies of transformation processes of these DBPs show

that detectable amounts of potentially dangerous substances cannot form under realistic

conditions. Thus, the conclusion is drawn that disinfection by-products and secondary

transformation species will not impose threats to crew, ship or environment as a result of the use

of the CleanBallast! ballast water treatment solution.

3.5.2.2 Hydrogen formation in the CleanBallast! under worst-case operation

Hydrogen gas can potentially form during the electrolytic disinfection process (reaction

mechanisms compared and extensively described in the separate application for Basic Approval, MEPC 55/2/4). The reduction of oxygen dissolved in the water, as well as reduction of various

oxidative species and disinfection by-products are competitive reaction to formation of hydrogen

gas. Due to the oxygen and hydrogen overpotential of the electrodes used in the EctoSys

electrolysis, the hydrogen gas production is significantly lower compared to conventional

chlorine electrolysis. Therefore, in the case of the CleanBallast! system no harmful

concentrations will build up in the ballast water tanks or surrounding systems. The

GESAMP-BWWG proposed further investigations on potential hydrogen gas formation in

full-scale ballast water treatment systems (MEPC 55/2/16, annex 7, paragraphs 10.2.2

and 10.2.3) and that a safety factor of at least 2 should be applied. Both theoretical calculations

and measurements at critical points in the surrounding system confirm no possible build-up of

explosive levels of hydrogen gas in any part of the CleanBallast! system or surrounding systems, applying safety factors up to 16. For obvious reasons, the ballast water tanks are open to

vent during ballasting and deballasting, making it impossible to build up explosive

concentrations (4%) of hydrogen gas in the ballast water tanks. Additionally to the low amount of

hydrogen theoretically formed, a reliable degassing is included after the EctoSysÆin the

CleanBallast! system during the land-based type approval and for on-board installations.
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3.5.2.2.1 Theoretical maximum production of hydrogen

The maximum total amount of an electrochemically formed substance on each electrode of an

electrolytic cell is directly proportional to the quantity of electricity passed through the cell. This

relationship is simplified into the so-called Faraday's first law, which can be generally applied:

Where, m is the mass of the substance produced at the electrode (in grams), Q is the total electric charge that passed through the solution (in coulombs), n is the valence number of the substance as an ion in solution (electrons per ion), M is the molar mass of the substance (in grams per mole).

To form one molecule of H2 from water is needed 2 e

-, thus n = 2. Molecular mass of hydrogen

gas is approx. 2 g/mol. Running the system for 1 h at maximum current (800 A), 100% current

exchange for cathodic hydrogen production (i.e., the unrealistic case were unwanted hydrogen

formation is the only reaction occurring at the cathodes), will thus theoretically result in

about 30 kg of hydrogen carried by in total 500 m

3 ballast water, corresponding to 0.006w

/0 of the

effluent water.

3.5.2.2.2 Measurements of hydrogen at critical points in a full-scale (500 m

3

/h) system

During the land-based type approval process, hydrogen have been monitored both continuously

and measured manually using a portable instrument. The online measurements were done as

follows:

After the water outlet of the EctoSysÆcell, an extended pipe as gas trap is installed that

traps reliably the hydrogen. An air release valve is working continuously at the top, at

which exhaust gas line a hydrogen sensor type Dr‰ger PEX 3000 was installed. This deaeration pipe serves as the critical spot where the most hydrogen would potentially

accumulate and be removed purposefully outside to the ambient air.

The lower explosion limit for hydrogen gas at normal pressure and temperature is 4.0 Vol.-% H2, corresponding to 3.36 mg H2 per dm

3 air, which is X % on the measuring range of the Dr‰ger

PEX 3000. The hydrogen measuring calibrated range was 5 ñ 100% of lower explosion limit,

i.e., 0.2 - 4

w

/0 total H2 content in the gas.

A second, manual measurements of the hydrogen concentration were done as follows:

As a comparison to the online hydrogen gas monitoring, water samples from the

electrolysis outlet have been examined by means of gas tube tests Dr‰ger type CH 30 901. This gas pipe test boasts a measuring range of 0.5 ñ 3.0 Vol. % H2 (corresponding

to 12.5 ñ 75% of the lower explosion limit of 4%). Measuring over outlet trapped flow

simulates worst-case scenario in a ballast water tank as a critical spot.
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During the measurements, the electrochemical cell was operated with constant worst-case high

current for maximum hydrogen production, at the same time varying the ballast water flow-rate

through the system expecting potentially higher H2 accumulation at lower flow rates (that would

only occur during incorrect operation or other malfunctions).

The reading of the online instrument was done at the same time as the sampling for the tube test. Table 7 shows an overview of operating parameters and results.

Table 7: Hydrogen formation at potentially critical spots during worst-case operation of

the CleanBallast! *Dr‰ger Online PEX 3000, **Dr‰ger-tube-test

Flow rate Current/ cell-pair Measurements

Deaeration

pipe* Outlet waterflow**

[m

3

/h] [A] [Vol.-% H2] [Vol.-% H2]

400 400 < 0.20 0.15

300 400 < 0.20 0.15

200 400 0.24 0.25

Another critical spot where hydrogen may theoretically possibly accumulate is the venting pipe

on top of the ballast water tank. For measuring the hydrogen content of the exhaust air at

this point, a hand-held hydrogen instrument (Dr‰ger PACIII; range 0-2000 ppm which

equals 0-0.2 Vol.%) was used. The results varied between 185 ppm up to 1950 ppm at the

ballasting operations during the LBTA process. Thus, at this spot not even 0.2 Vol.% was

reached under worst-case conditions.

In the normal operation of the CleanBallast!, no degassing occurs due to the pressurized system

and the low amount of hydrogen produced, which has to be assumed as completely dissolved in

water. Measurements of the gas volume produced by the EctoSysin the full-scale CleanBallast!

were carried out by selectively trapping the gas volume after the EctoSyswith release against

atmosphere. Even under worst-case conditions in low salinity water (< 0.2 psu), where the high

electrode potentials lead to more electrochemical discharge through common water electrolysis

and, hence, the formation of hydrogen is favoured at a water flow rate of 500 m3/h, the produced

gas volume was very low ñ in the position after decimal point of the liter per hour range ñ and

consists of mixed gases e.g., oxygen and hydrogen.

3.5.2.2.3 Conclusions on hydrogen formation in the CleanBallast!

No concentrations of hydrogen gas even close to levels relevant to safety issues are detected in

the gaseous phase directly above the treated water at worst-case running conditions of the

CleanBallast! ballast water treatment system. The highest measured value including all critical

spots was 0.25 %, which corresponds to 6% of the lower explosion limit. This value was

achieved under extremely forced conditions (i.e., extreme incorrect use of the system) and

resulted to a safety factor of 16.
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The online measuring and the tube test used for comparison purposes show identical results. As

an additional safety measurement, the power control of the EctoSysÆshuts automatically down in

case too high hydrogen gas concentrations would be detected by the online monitor in the

deaeration pipe after the EctoSysÆ. Due to the low gas volume and the low volumetric hydrogen

gas concentration produced and, consequently, the high safety factor, no further safety

precautions are necessary besides the gas trap after the EctoSysÆwith deaeration pipe going

selectively to the atmosphere/outboard.

Taking all facts into account, hydrogen formation in the CleanBallast! can not pose any threat to

crew, ship or environment.

3.6 Whole-effluent characterization

A chemical characterization of the whole effluent including sludge was carried out according to

Methodology for information gathering and the conduct of work of GESAMP-BWWG

(MEPC 55/2/16, annex 4) hereinafter referred to as ëthe Methodologyí. Transformation

processes of relevant DBP were investigated theoretically in order to exclude them from the risk

assessment (see section 3.5.2.1.4).

Test conditions:

Brackish water with salinity range 11- 15 psu (Bremerhaven)

3.6.1 Characterization of discharged sludge

Characterization of discharged sludge was in accordance with section 3.5 of the Methodology for

treated ballast water. The following parameters were analysed in the influent of the treatment and

control line as well as in the discharge sludge line during backflushing of the filters at ballasting

procedure, all listed in Table 8.

Table 8: Characterization of discharged sludge during LBTA test cycle 3, ballasting

sequence compared to the influent of treatment and control line

Parameter Unit Inlet treatment A Inlet Control D Sludge S

pH-value - 7.72 7.80 7.49

Practical salinity units psu 14.80 14.80 14.80

Dissolved Oxygen (on-site) mg/l 4.90 5.20 4.90

Redox potential mV 344 375 305

Total Suspended Solids (TSS) mg/l 101 94 91

Total Organic Carbon (TOC) mg/l C 35.63 32.33 57.35

Dissolved Organic Carbon (DOC) mg/l C 19.40 18.33 11.10

Particular Organic Carbon (POC) mg/l C 16.23 14.00 46.25

Ignition loss % 78.00 76.67 90.60

Settling Solids ml/l < 0.2 < 0.2 < 0.2

Density g/ml 1.009 1.009 1.009

Turbidity NFU 37.43 36.70 44.40

Ballasting Procedure
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The filters are backflushed during ballasting by using the cleaned effluent. Besides slightly

higher Total and Particular Organic Carbon concentrations, there is no significant difference

between the inlet water (pumped harbour water) and the sludge discharged right back to the

receiving source/harbour water.

3.6.2 Chemical characterization of the whole-effluent water

Chemical water parameters were analysed and/or on-line monitored during both LBTA ballasting

phase and deballasting phase, according to the Methodology. Table 9 shows an example of

results from one LBTA test cycle. Disinfection by-products were also analysed, see further

sections 3.5.2.1 and 3.6.2.1.

Table 9: Characterization of whole-effluent discharged water during LBTA test cycle 5, deballasting sequence compared to ballasting inlet for treatment and control

Ballasting procedure

Parameter Unit Inlet treatment A Inlet control D

pH-value - 7.08 7.15

Practical salinity units psu 14.30 14.30

Oxygen (dissolved) mg/l 3.60 5.33

Redox potential mV 435 453

Total Suspended Solids (TSS) mg/l 101 102

Total Organic Carbon (TOC) mg/l C 31.30 35.33

Dissolved Organic Carbon (DOC) mg/l C 18.90 17.43

Particular Organic Carbon (POC) mg/l C 12.40 17.90

Ignition loss % 71.90 76.60

Settling Solids ml/l <0.2 <0.2

Density g/ml 1.008 1.008

Turbidity NFU 32.23 28.70

Deballasting procedure

Parameter Unit Effluent treatment C Effluent control E

TRO mg/l 1.6

pH-value - 7.11 6.82

Practical salinity units psu 14.20 14.20

Oxygen (dissolved) mg/l 8.00 4.27

Redox potential mV 234 345

Total Suspended Solids (TSS) mg/l 12 14

Total Organic Carbon (TOC) mg/l C 3.67 4.73

Dissolved Organic Carbon (DOC) mg/l C 1.93 2.43

Particular Organic Carbon (POC) mg/l C 1.73 2.30

Ignition loss % 28.27 53.83

Settling Solids ml/l <0.2 <0.2

Density g/ml 1.008 1.008

Turbidity NFU 3.25 7.52

As expected, the turbidity, TSS and POC concentrations are lower in the effluent of the treatment

after the deballasting compared to the control line. Furthermore, the oxidizing treatment increases

the dissolved oxygen concentration of the discharged water compared to the control line. All other parameters are not significantly changed by the CleanBallast! treatment.
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3.6.2.1 Analysis of disinfection by-products (DBP)

Analysis of the production (in natural waters) of THM (especially bromoform), AOX and HAA

as well as bromate under different operating conditions of the LBTA system and different

salinities was done. See further section 3.5.2.1.

3.7 Toxicity studies of whole-effluent water

3.7.1 Acute toxicity

The GESAMP-BWWG raised concerns over possible cumulative toxic effects of Active

Substances and Relevant Chemicals, and this can only be studied taking a whole-effluent

conservative approach. All brackish water tests on whole-effluent acute toxicity were carried out

using samples taken during land-based type approval procedure according to Procedure (G9). All these samples were taken from the effluent directly after the disinfection unit during the

deballasting operation of the LBTA process (water treated at a flow rate of 500 m

3

/h, stored for

five days, treated again and sample water immediately taken from treatment outlet and sent to

lab, or collected for the on-site measurements). Due to the short half-life and rapid decay of

Active Substances, the general approach used was to determine the initial toxicity of the water, along with determining the decrease of toxicity over time as well as parallel measurement of the

TRO. Studies of the degradation of toxicity during the initial period after treatment were

recommended by the GESAMP-BWWG in their evaluation of the submission for Basic Approval

to the disinfection unit (MEPC 55/2/16, annex 7, paragraph 10.4.2.2). All tests were made taking

a conservative ìworst-caseî approach, i.e., the disinfection unit included in the CleanBallast!

LBTA set-up was optimally adjusted for maximized, high production of TRO, which is judged to

be the primary cause of acute toxicity or precursors for by-produced toxic species. This assumption was supported by the GESAMP-BWWG in the evaluation (MEPC 55/2/16, annex 7, paragraphs 9.2.2 and 10.3.3) of the application for Basic Approval (MEPC 55/2/4).

The intention was to use as sensitive organisms as possible in the tests. The Active Substance of

free active chlorine is formed in the disinfection process of the CleanBallast! system, using

chloride ions (MEPC 55/2/4, paragraph 4.3.2) as precursor. Free active chlorine is the reactant

mostly responsible for the measured TRO value, being set to equilibrium by the actual natural sea

water parameters. Fresh water contains very low concentrations of chloride; therefore, TRO is

formed in much lower quantities and also much higher degradation rates. Guidelines (G8) require

land-based full-scale tests in at least two different salinities, and therefore acute toxicity tests on

three tropic levels were also performed in fresh water along with the acute tests in brackish water

and the chronic studies in full salinity water. No residual toxicity was expected in such waters. Due to the predominant production of short-lived OH-radicals as oxidants, the TRO

concentration in the fresh water could not reach 2 mg/l and the worst-case approach could not be

fulfilled. The results from the acute toxicity tests can readily be submitted to the

GESAMP-BWWG if requested. Worst-case studies of acute toxicity of effluent from the

disinfection unit alone in full salinity (35 psu) sea water have been performed and reported

previously in the application for Basic Approval (MEPC 55/2/4).
MEPC 57/2/3

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3.7.1.1 Brackish water studies

Test conditions:

Brackish water with salinity range 11-15 psu (Bremerhaven)

Worst-case disinfection (Initial TRO levels <=2 mg/l)

Performance Standard D-2 fulfilled.

3.7.1.1.1 Degradation of TRO

The degradation of TRO was measured using the standard DPD method (Dr. Lange) for free- and

total active chlorine measurement. It is well known that this technique (based on DPD reagents)

responds to all oxidative species interpreted as TRO. Results confirm the previous results and

statements (MEPC 55/2/4, paragraph 5.2.7.2) that the TRO degrades rapidly during the

first 20 minutes. Figure 3 shows measured TRO decay over the initial time period after treatment

in undisturbed stored samples taken from the effluent (sample port C) during the five first LBTA

deballasting procedures in brackish water. For each time interval, a sub-sample was taken from

the stored effluent sample and consequently analysed for TRO.

TRO degradation in CleanBallast! deballasting effluent

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1.6

1.8

0 20 40 60 80 100 120 140 160

Time [min]

T

R

O [m

g/l]

LBTA cycle 1

LBTA cycle 2

LBTA cycle 3

LBTA cycle 4

LBTA cycle 5

Fig. 3: TRO decay in stored effluent from the LBTA type approval set-up (without discharge to the receiving water)

Background DPD response of the natural harbour water is about 0.2 mg/l, which in all cases was

reached after approximately 150 min. Interpreting these results, it has to be stressed that the

effluent samples were stored shielded from the sunlight and, therefore, again a worst-case

approach was applied. Studying the sunlight-induced photochemical decay of different oxidants

in natural water for implication in ballast water treatment, Cooper et al. (2007) gave reaction

half-lives of approximately 11 min. for HOCl/OCl

- and 20 min. for HOBr/OBr- at pH 8. Depending on the point of discharge of the ship and mixing/turbulence of the receiving water the

photo-induced decay of chlorine and bromine has to be considered in the treated and discharged

water and might cause a faster TRO decay as shown in the undisturbed samples in Fig. 3 and

therefore lower secondary by-products formation.
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3.7.1.1.2 Kinetic Ekotox

Tetraselmis suecica is used as a test organism throughout the LBTA process according to

Guidelines (G8) and has also been used over a long period of time in testing the performance of

the CleanBallast! system. The experience of this organism is considered quite wide. Therefore,

there is an advantage of using the same organism in order to study the decay of toxic substances

and link decrease in toxicity to decay of TRO. The toxicity decrease over time from the initial

toxicity of the treated water down to non-toxic levels was studied by exposing a constant, known

cell density of viable Tetraselmis to each sample taken from the stored effluent of the

CleanBallast! system from deballasting after different storage times of the effluent. The studies

were performed on-site at the LBTA plant for immediate access of treated water. The viability

was determined by measuring the fluorescence signal of the dosed viable Tetraselmis cells in the

treatment effluent from deballasting procedure compared to control. In this case, as control, the

undisturbed harbour water at the point of later discharge (1 m from the discharge point, 30 cm

below the surface) was used. Fig. 4 shows an example of the results of the Kinetic Ekotox

studies, which corresponds well with both the TRO decay pattern and the Microtox

Æ

analysis

(see sections 3.7.1.1.1 and 3.7.1.1.3).

0.0

0.2

0.4

0.6

0.8

1.0

1.2

0 20 40 60 80 100 120 140 160

Time after disinfection [minutes]

via

bility tre

ate

d / c

o

ntrol

LBTA cycle 2

LBTA cycle 4

LBTA cycle 5

Fig. 4: Kinetic toxicity response of Tetraselmis from stored effluent from deballasting procedure in LBTA

cycle 2 (1.6 mg/l initial TRO, 4 (1.5 mg/l initial TRO) and 5 (1.2 mg/l initial TRO) related to the

undisturbed receiving water as control

The GESAMP-BWWG raised concerns over possible acute toxicity of receiving waters close to

the discharge point, when large amounts of ballast water is being discharged (MEPC 55/2/16, annex 7, paragraph 9.3.4). Analysis of the Tetraselmis response to residual toxicity has been

performed immediately on water samples taken 1 m from the discharge point, 30 cm below the

surface during deballasting 500 m

3

/h from the LBTA system. The undisturbed harbour water at

the discharge point was used as control here. Complementing harbour water samples taken from

representative distances away from the discharge point (corners of the barge where the tests
MEPC 57/2/3

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LBTA tests were done) also analysed with the same method, in parallel with TRO analysis. The results are summarized in Table 10.

Table 10: Toxicity response of Tetraselmis and TRO value of samples taken at different

locations and times during and after the LBTA deballasting process and discharge

(treated) and control (= undisturbed harbour water at point of discharge before

treatment). *DP = Discharge Point

Sampling location&time Viability TRO [mg/l]

Control Treated Corners Control Treated Corners

Start 0.649 0.155

*DP 10 min deballast 0.584 0.581 0.150

*DP 20 min deballast 0.622 0.699 0.194

*DP 5 min after end of deballast 0,640 0.668 0.154

*DP 10 min after end of deballast 0.598 0.637 0.130

Right corner, before discharge 0.625 0.133

Left corner, before discharge 0.621 0.142

Right corner, 30min discharge 0.622 0.137

Left corner, 30min discharge 0.642 0.148

The deballasted effluent had an initial mean TRO concentration of 1.7 mg/l in this test. The concentration 1 m from the discharge point during deballasting, 30 cm below surface, showed an initial 5-10 % increase compared to natural harbour water. As can be seen in these

data, no significant increase in toxicity were found amongst the samples that were taken. This confirms that CleanBallast! effluents will not cause acute toxicity in recipient waters even

under worst-case conditions.

3.7.1.1.3 Luminiscense bacteriatest (Microtox

Æ

)

The acute toxicity of the whole-effluent was measured using Microtox

Æ method, both immediate

on-site measurements and on samples transported to a nearby lab for reference. Microtox

Æ

is a

standardized toxicity test system which is rapid, sensitive, reproducible and ecologically relevant.

It is recognized and used throughout the world as a standard test for aquatic toxicity testing and

known to be very sensitive against most toxic agents.

The procedure employs the bioluminescent marine bacterium (Vibrio fischeri) as the test

organism (protocol ISO 11348-2-L34:1998-12). The bacteria are exposed to a range of

concentrations of the water being tested. The reduction in intensity of light emitted from the

bacteria is measured along with standard solutions and control samples. The change in light

output and concentration of the toxicant produce a dose / response relationship. The results are

normalized and the EC50 (concentration producing a 50% reduction in light) can be calculated.

The on-site measurements were included because of the rapid decay of the TRO judged

responsible for toxicity, and the results correlate well with the parallel TRO degradation and

Kinetic Ekotox tests. An example of the result (well reproduced) is shown in Table 11.
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Table 11: MicrotoxÆ EC50 values of CleanBallast! treated effluent

and control line effluent

Time after sampling (min) Treated Effluent Control

10 EC50 > 500 ml/l EC50 < 83.3 ml/l

45 EC50 = not reached ------------------

90 EC50 = not reached -------------------

It was found that there was an unexpected high toxicity in the untreated control water, which

consists of harbour water stored 120 h according to Guidelines (G8). This toxicity was assumed

to have been caused by anaerobic decomposition products (e.g., H2S) formed during storage in

the control ballast water tank of the LBTA. Analysis on H2S in the control water confirmed this

by showing values of > 2 mg/l H2S present in the control tank. The action of sulphate-reducing

bacteria forming H2S is well known, which leads to microbial-introduced corrosion in current

ballast water tanks (Hill 2003).

To investigate the theoretical possibility of toxic substances forming over time in water treated

with the CleanBallast! system, reproduced Microtox

Æ

analysis at the laboratory was also done on

water samples taken at the LBTA deballasting procedure. No toxicity was found in the treated

samples in any case.

3.7.1.1.4 Marine algae

Protocol: ISO/DIS 10253:2005-02

Species: Phaeodactylum tricornutum

The marine algae acute tests were done to the EC50 endpoint. The ìGAî-value is an abbreviation

for the German ìGiftgigkeit gegen ̧ber Algenî. It means, i.e., the highest test batch where no

inhibition or only very low effects (< 20 %) appear. Table 12 shows the result from tests on water

samples taken at the deballasting phase of LBTA cycle 2:

Table 12: Results of Marine Algae acute test on water taken at LBTA deballasting

GA EC50 (ml/l)

Treatment 4 380

Control 32 90

3.7.1.2 Fresh water studies

Test conditions:

Fresh water conditions salinity < 3 psu
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The following acute toxicity studies were performed on whole-effluents from the CleanBallast!

during the LBTA procedure:

Invertebrate test: Test protocol: DIN 38412-30

Test species: Daphnia magna

Algae test: Test protocol: DIN 38412-33

Title: German standard methods for the examination of water, waste water and sludge; bio-assays (group L); determining the

tolerance of green algae to the toxicity of waste water

(Scenedesmus chlorophyll fluorescence test) by way of dilution

series (L 33)

Vertebrate test: Test protocol: DIN 38415-6

Test species: Danio rerio

The results from the acute toxicity tests in fresh water can readily be submitted to the

GESAMP-BWWG if requested..

3.7.1.3 Conclusions

The results from acute toxicity studies of whole-effluents from the land-based type approval

process according to Guidelines (G8) show no significant residual acute toxic effects caused by

treatment with the CleanBallast! system. The toxicity of the water was confirmed to be linked to

the TRO concentration in the water at a specific time, and no toxicity could be detected in waters

after storage of the effluent without any dilution. The initial toxicity will thus rapidly decrease

during the first 20-30 min. after treatment, directly proportional to the decay in TRO

concentration. The marine bacteria Vibrio fisheri, which are known to be very sensitive towards

toxic agents, showed the same response as the test organism Tetraselmis strongly correlating with

the decay of TRO.

The GESAMP-BWWG raised concerns over possible acute toxicity of receiving waters close to

the discharge point, when large amounts of ballast water is being discharged (MEPC 55/2/16, annex 7, paragraph 9.3.4). Analysis of the TRO concentrations and toxicity response on

Tetraselmis of samples taken 1 m from the discharge point, 30 cm below the surface during

deballasting 500 m

3

/h from the LBTA system showed no significant changes to natural harbour

water.

The acute tests previously made for ìBasic Approvalî of the EctoSysÆdisinfection unit alone

showed a NOEC of 3% on all trophic levels at TRO values twice as high as used by the

CleanBallast!, and without any filtration. Accordingly, much higher corresponding EC50/LC50

values were noted from these tests using water treated by the complete CleanBallast! system. Thus, it can be concluded that the assumptions regarding toxicity (i.e., higher toxicity in waters

treated by the disinfection unit alone) in the application for Basic Approval were correct.
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3.7.2 Chronic toxicity

The general approach to study the chronic toxicity of natural sea water treated with the

CleanBallast! ballast water treatment system was to determine the chronic toxicity at different

worst-case constant TRO/DBP concentrations, which due to the rapid decay of these substances

was not possible to achieve during natural conditions or directly at the land-based type approval

installation. Decisive for the toxicity is not the scaling factor of the treatment system, but the

same TRO level achieved by each treatment system. Therefore, a separate set-up for the chronic

toxicity studies was developed and build directly at the lab performing the studies. The set-up

consisted of the CleanBallast! disinfection unit (10 m3/h) continuously providing the chronic tests

with worst-case effluent water, which in turn was diluted in series according to the respective test

protocol. Tests were performed at three trophic levels in accordance with the Procedure (G9). The selected test species (except the fish) were previously used for acute tests during the ìBasic

Approvalî procedure, and this provides a link between the approach to acute and chronic tests, as

well as the studies related to the ìBasic Approvalî and the ìFinal Approvalî.

3.7.2.1 Test conditions and production of the whole-effluent

Filtered natural sea water (32-35 psu, filtered < 10 μm) is treated with the CleanBallast!

disinfection unit, and led to an overflow tank from which the sample streams are taken. The TRO

level in the dosing tank is kept constant at worst-case level of 2 mg/l, verified by the DPD

method. The sampling water is divided into sub-streams and led continuously (+ diluted

accordingly) to the test facilities according to the OECD procedures (dosing or flow-through) in

order to maintain the concentration of the TRO/DBPs exposed to the organisms throughout the

test period.

3.7.2.2 Marine algae

Protocol: ISO 10253:1995(E), Water Quality ñ Marine

algal growth inhibition test with Skeletonema

costatum and Phaeodactylum tricornutum

Species: Skeletonema costatum

Duration of test: 96 hours

Results:

96 hour EbC50 3.9%

v

/v 96 hour ErC50 6.3%

v

/v NOEC biomass Not determinable

NOEC growth 3.2%

v

/v
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3.7.2.3 Invertebrate test

Protocol: According to OECD 211 (marine equivalent) ìSurvival & reproduction test on Invertebrate

(Thisbebattagliai)î

Species. Thisbebattagliai

Duration of test: 21 days

Results:

NOEC survival 1 %

v

/v NOEC reproduction 3.2%

v

/v LOEC survival 3.2%

v

/v LOEC reproduction 10%

v

/v

3.7.2.4 Vertebrate (fish) test

Protocol: According to OECD 210 (adopted 17 July 1992) ìDetermination of the effect of a chemical on the

embryo larval development of the Sheepshead

Minnow (Cuprinodon variegates)î

Species Cuprinodon variegates (Sheepshead Minnow)

Duration of test 32 days

Results: Hatch Survival Length Dry weight

NOEC (mg/l) 3.2 1.0 10 10

LOEC (mg/l) 10 3.2 -- --

Therefore, for all the biological parameters included in the evaluation (hatch, survival,

length, and dry weight) the overall results are:

No Observed Effect Concentration (NOEC) 1.0 mg/l

Lowest Observed Effect Concentration (LOEC) 3.2 mg/l
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3.7.2.5 Chemical analysis on the effluent used in the chronic toxicity studies

Water used in the chronic toxicity studies was chemically analysed for routine parameters, both

treated waters, control waters and dilution waters. Examples of parameters in the treated effluents

are summarized in Table 13.

Table 13: Routine water parameters in water used in the chronic toxicity studies

pH

*

Salinity

*

(â)

Ammonium nitrogen

as N

(Ïg/l)

Number of samples 25 25 1

Minimum 7.98 34.5

Maximum 8.17 35.2

Mean NA 34.7

<10.00

NA = Not applicable

3.7.2.6 Conclusions

The chronic toxicity of the water will be negligible at TRO/DBP levels relevant to the

environment applying CleanBallast! to ballast water treatment worldwide. Combined with

dilution/discharge modelling, acute toxicity studies, analysis of the toxicity degradation, these

chronic studies are assessed to give the full picture for environmental Risk Assessment of the

system.

3.8 Simulating emission scenarios for ballast water discharge

Modelling of ballast water discharges in generic open and closed harbours as well as case studies

of ballast water discharge in Bremerhaven, based on the worst-case acute NOEC values of the

disinfection unit effluent, have already been carried out and reported in the application for Basic

Approval (MEPC55/2/4). This was complemented with new simulations at the actual site of the

land-based type approval installation (Bremerhaven), using data relevant for the complete

CleanBallast! system e.g., two times lower TRO as use for the EctoSysÆdisinfection alone in the

Basic Approval. The model predictions were also controlled by manually taking samples at

different distance from the discharge point, and measured for Total Residual Oxidant (TRO). Using the predicted and measured TRO values, it was then possible to correlate discharge

scenarios to both toxicity studies and the chemical characterization of the treated water.

Physical processes (i.e., mixing), will be different for every port and variable within a port, depending primarily on factors such as fresh water input dynamics, tides, and winds. Mixing will

have two components, vertical and lateral, to disperse the oxidant away from the shipís point of

discharge. To assess the potential effect of mixing, the overall decay half-life of the oxidant has

to be considered. Modelling of the ballast water discharge dilution in generic harbours down to

the acute NOEC (using a safety factor of 10) resulting from the Final Approval toxicity tests, and

also down to the chronic NOEC (incl. safety factor) was performed as a more direct supplement

to the toxicity studies. A specific generic harbour scenario was developed using available data

from the harbour of Rotterdam. Rotterdam was chosen because similar evaluations have been

done using this port before and can be used as reference/comparison to the approach of the
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applicant. This specific latter study was used to determine a realistic PEC/PNEC ratio, provided

all ships in a representative commercial harbour were equipped with the proposed CleanBallast!

system and under worst-case treatment and discharge conditions. This might also be of use in

later joint-efforts of developing an ESD for BWT (see section 3.8.4).

3.8.1 Extended generic harbour models

The generic open/closed harbour simulations previously used for the application for Basic

Approval was complemented with runs down to both relevant acute and chronic NOEC values,

including a safety factor of 10. Re-runs of the existing models were done for the following:

 Dilution down to acute NOEC of 0. 3% v/v (value from Basic Approval project, disinfection unit only, incl. safety factor)  Dilution down to chronic NOEC of 0.1% v/v (value from Final Approval studies, disinfection unit only, incl. safety factor)

The definitions for generic harbours and default vessels were the same as those used for the

application for Basic Approval to the EctoSysÆ disinfection unit:

Closed - 800 m  190 m, depth 12 m., 1 ship at 400 m, 10 m with discharge onto surface

Tidal - 7000 m  300 m, depth 12 m, 1 ship at 3500 m, 10 m with discharge onto surface

With the discharge scenarios defined by the number of ships, their positions and certain loads, the

model was used to predict the time taken for concentrations to fall below 0.3% and 0.1%,

respectively, of the neat effluent concentration. With the first-order degradation rate set to fit real

data measured in Bremerhaven during the LBTA test cycles, the results could be summarized in

Tables 14 and 15. Table 14: Generic harbour modeling results for a closed harbour

Discharge

rate

(m

3

/h)

Discharge

duration

(h)

Time for

concentration to

reach 0.3%

(h)

Time for

concentration to

reach 0.1%

(h)

1000 5 4 5

1000 10 4 5

5000 5 6 7

5000 10 6 7

Table 15: Generic harbour modeling results for a tidal harbour

Discharge

rate

(m

3

/h)

Discharge

duration

(h)

Time for

concentration to

reach 0.3%)

(h)

Time for

concentration to

reach 0.1%

(h)

1000 5 2 2

1000 10 2 3

5000 5 3 4

5000 10 3 5
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3.8.2 Case study of the effluent discharge from the land-based type approval set-up in

Bremerhaven.

In order to verify the predictions of the computer models, the land-based type approval test was

chosen as a suitable case-study project. The LBTA set-up was located at a barge in Bremerhaven, were various tests linked to the type approval procedures were performed simultaneously during

the deballasting procedure according to Guidelines (G8). The model simulated the discharge and

dilution of the Active Substances in the ballast water discharge coming out at this particular

discharge point into this particular receiving environment, taking into account relevant

worst-case initial TRO concentrations, total discharge volume, discharge rate and relevant

degradation rates (which were measured on-site). The output response predicted the

concentrations at different distances and depth from the discharge point at a certain time. Then

samples verifying the model were taken at representative locations and analysed. The results

clearly showed that the data from real measurements are below data predicted by the model. This

supports the assumption that the modeling approach returns a conservative absolute worst-case

picture of real scenarios. This particular modeling exercise confirms that discharges of TRO from

the CleanBallast system would make a negligible contribution to harbour concentrations (7%)

shortly after discharge. 7.5 hours after the discharge ceases, TRO concentrations occurring in the

harbour has been diluted/degraded to ~1 ng/l.

3.8.3 Case study of commercial harbour including PEC/PNEC calculation

Rotterdam has been suggested as a representative of a heavily trafficked port where estimations,

risk assessments etc. can be made, mainly because it has been used in such studies before

(e.g., ESD for protective coatings on ship hulls) and relevant parameters is relatively well- known.

The case-study of Rotterdam was developed from a closed generic harbour scenario, with

relevant data for Rotterdam (from MAM-PEC) used and assuming all ships trafficking it would

be equipped with the CleanBallast!. A worst-case (but non-realistic) approach was taken, e.g., all

ships discharging maximum volumes of ballast water at maximum pump capacity flow rate and

worst-case initial TRO concentrations in the discharged ballast water. Balancing this, a relevant

exchange period of the harbour water volume, a relevant degradation of the TRO

(first order degradation equation, based on real data measured during TRO degradation in natural

harbour water) and normal (Fickian) dilution were introduced in the model. Then the medium

overall steady-state PEC could be calculated, using a safety factor of 10, and compared to

acute/chronic toxicity data. As a relative PNECTRO-saltwater value, the corresponding value for TRC

in sea water was used: 0.3 μg/l (Including a safety factor of 10, derived in the application for

Basic Approval MEPC 55/2/4, paragraph 5.2.10.2).

A steady-state PEC of the TRO in Rotterdam under unrealistic worst-case conditions was

predicted by the model to be 0.12 μg/l. Applying the recommended safety factor, then the

PEC/PNEC ratio could be calculated to 0.4.

In consideration of this evaluation using relevant safety factors and unrealistically conservative

worst-case approaches on all levels, it is assessed that using the CleanBallast! system world-wide

would not pose any threat to the environment even locally in heavily trafficked ports.
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3.8.4 Emission Scenario Document (ESD)

The GESAMP-BWWG has requested indications on the basis of the exposure and risk

assessment, preferably in the form of a suitable Emission Scenario Document (ESD) which

should be adopted by MEPC (MEPC 54/21, paragraph 2.12; MEPC 55/2/16, paragraph 5.8.8). The GESAMP-BWWG welcomed the submission by the United Kingdom to BLG (BLG 11/4/11)

that made suggestions for a possible outline of a specific ESD tailored to a specific treatment that

could be used in the process of Final Approval (MEPC 56/2/2, paragraph 5.3.7). The GESAMP BWWG also encouraged the MEPC (MEPC 55/2/16, annex 7, paragraph 10.4.4) to

consider the development and agreement of representative and realistic emission scenarios to be

applied by the applicant. The applicant welcomes these recommendations, and also recognizes

that the potentially useful models mentioned by the GESAMP-BWWG (MEPC 56/2/2, paragraph 5.3.1) are available. However, in order to receive the most relevant data, it is the

opinion of the applicant that a model specifically tailored for simulating ballast water discharge

into natural waters and environments would be the preferable alternative. These kinds of models

should also be developed for specific case-studying of existing ports. The approach and

worst-case outcome of such a case study (using existing data on the port of Rotterdam) related to

the CleanBallast! system is presented under section 3.8.3, and the full report included in the

application dossier for Final Approval submitted to the IMO.

3.9 Human Exposure Scenario

In considering the need for a Human Exposure Scenario (HES), the GESAMP-BWWG agreed

that in order to identify the risks associated with human exposure and safety of the ship, it was

particularly important to (MEPC 56/2/2, paragraph 5.2.1):

.1 provide a full description of the processes and individual operations in which

human exposure may occur;

.2 ascertain duration and frequency of such tasks;

.3 identify situations in which a reduction of amenities and interferences with other

uses of the sea might be caused by the discharge of treated ballast water into the sea;

.4 identify Personal Protective Equipment (PPE) and control measures to be used in

order to reduce and mitigate exposure; and

.5 ascertain the potential of the system to cause damage to the ship or its equipment.

The Active Substances produced and used by the CleanBallast! system are produced directly in

the water without any external adding of chemicals. Therefore, no handling of the Active

Substances, Relevant Chemicals or Preparations will be performed by humans during any

processes or individual operations on board. The GESAMP-BWWG also recognized that the

only possible exposure scenario would be leaking pipes, but assessed the levels of the Active

Substance of free active chlorine to be harmlessly low even in this case (MEPC 55/2/16, annex 7, paragraph 10.2.4). As a comparison, the free active chlorine concentration used for disinfection

of drinking water is ≤ 5 mg/l throughout the distribution system on board (USPH EPA). Therefore also, the use of PPE specifically in order to protect against Active Substances used in

ballast water treatment operations will not be required. Furthermore, the CleanBallast! system is

automatically shut-down in case of a leakage and the by-pass around the system is opened.
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The Active Substances will be present in the ballast water discharge and by this potentially

interfere with other uses of the sea. However, the low initial concentrations of the Active

Substances along with the rapid decay will prevent all hazards to and disturbances for amenities

or other uses of the sea. The discharge and dilution of the ballast water containing worst-case

concentrations of the Active Substances have been studied by modeling generic open/closed

harbours as well as case studies (see section 3.8).

The Active Substances will be present in the treated ballast water entering the remaining ballast

water system and finally the ballast tanks at the worst-case concentration of 2 mg/l or below this

concentration. Studies have shown that different oxidative species will have an impact on the

corrosive properties of the ballast water (BMT Fleet Technology Ltd.). The Active Substances

used by the CleanBallast! system will be present in such low concentrations and have such short

half-life in natural waters so that the natural corrosion course will not be enhanced in any way. However, an extensive study verifying this under worst-case conditions with regards to ballast

water tanks, materials, coatings etc. is also currently on-going and will be reported

(see section 3.10).

3.10 Corrosion

The GESAMP-BWWG welcomed the fact that an evaluation of the corrosive properties of water

treated with CleanBallast! should be done (MEPC 55/2/16, annex 7, paragraph 10.1.1). Corrosion

studies are also required for evaluation for type approval certificate to be issued, and the system

to be used on-board ships. Guidelines for such a corrosion evaluation of the CleanBallast!

effluent have been developed in co-operation with the classification society Germanischer Lloyd

(GL) and a well-recognized corrosion institute of northern Europe. GL concludes a number of

ISO/ASTM standard corrosion test methods useful for such an evaluation. However, these

standards focus on the evaluation of steels, paints and varnishes (using a ISO standardized test

water) instead of evaluation of media corrosiveness. Certain alterations from the standards, as

well as choice of standard steels and coatings used for test panels, were necessary in order to

follow the GL recommendations and produce useful data. This was accepted by the GL as long

as every change and choice was well documented and motivated. For the test panels, an

assortment was made among the coated/uncoated types acknowledged by the GL, who also

suggests a range of coating thicknesses (250ñ500 μm). Corrosion studies are very time

consuming, simply because it takes a certain amount of time to see anything on the test panels. This fact implied an accelerated test approach. Therefore, the test panels first undergo an

accelerated ageing period in whole-effluents from the CleanBallast! system, and then be

evaluated under the standardized test protocol guidelines.

3.10.1 Test material

Both panels of coated steel and bare steel are tested. The corrosivity is calculated by weighing

the uncoated steel panels before and after the ageing. The coated steel test panels scribes are done

in the coating before ageing.
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3.10.2 Ageing

Four parallel tests are being performed with both coated and bare steel. Water parameters such as

e.g., pH, temperature, conductivity etc. are measured before and after treatment, as well as other

relevant parameters suggested by the GL that can be measured manually. Analyses of H2 are

being performed during the test. The test water is natural sea water (32-35 psu) which is assumed

as worst-case in respect of corrosive properties as well as potential formation of corrosion

enhancing oxidative species. Ageing time in full salinity sea water is assayed corresponds to the

expected exposure duration of a ballast tank to the disinfectant during its lifetime, including

relevant safety factor.

3.10.3 Evaluation

After the ageing test in sea water, the panels are evaluated according to the following standards

to see if there are any differences between the test panels that have been exposed to CleanBallast!

effluent continuously or intermittent and the ones that have been exposed to ìpureî sea water

continuously or intermittent:

ISO 9227 (has replaced ISO 7253) salt spray 1440 h

ISO 6270-2 (condense 1440 h)

ISO 2812-2 (immersion 3000 h)

ISO 15711 (cathodic ASTM G8-96 method, A 3000 h)

The final test report of the well-recognized corrosion institute will be evaluated by the

classification society Germanischer Lloyd.

4 RISK ASSESSMENT

4.1 Crew

Handling of the Active Substances and Preparations (G9, paragraph 7.1) is not an issue for the

system proposed by the applicant, where the Active Substances are formed in-situ. Personal Protective Equipment (PPE) specifically used in order to avoid contact with the Active

Substances is therefore not necessary. The theoretical electrochemical formation of the Relevant

Chemical of hydrogen has been proven by practical tests and measurements as well as

calculations to induce no potential danger (explosions etc.) for the crew. Additionally, in case of

a pipe leakage the CleanBallast! system will automatically shut-down and the by-pass around the

system will be opened.

4.2 Ship

Studies have shown that different oxidative species will have an impact on the corrosive

properties of the ballast water (BMT Fleet Technology Ltd.), potentially harmful to the ballast

water tanks on ships. The Active Substances used by the CleanBallast! system will be present in

such low concentrations and have such short half-life in natural waters so that the natural

corrosion course will not be enhanced in any way. However, an extensive study verifying this

under worst-case conditions with regards to ballast water tanks, materials, coatings etc. is also

currently being set up and will be reported (see further section 3.10). Today in the sea chest

previously to the ballast water system chlorine concentrations corresponding to the levels

relevant in the case of CleanBallast! ballast water treatment are already in use. Corrosion rates in
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general increase with salinity, however aqueous corrosion depends entirely on availability

of oxygen (BMT Fleet Technology Ltd.). When used as a biocide at room temperature

and pH 8.5, Franklin et. al.(1991) found that hypochlorite at two parts per million (ppm or mg/l)

had little effect on the corrosion rate of unprotected carbon steel because the biofilm was not

disturbed, but at the much higher concentration of 16 ppm a marked increase in corrosion was

noted. Besides the previous corrosion study, the chemical characterization of the whole-effluent

water presented in section 3.6.2 indicate that the treatment by the CleanBallast! system does not

change water parameters that are known to potentially have a major influence on the corrosion

rate, e.g., pH, redox potential and dissolved oxygen concentration.

4.3 Environment

Previous to the studies included in the Final Approval process, the whole-effluent tests and

analysis on acute toxicity for the EctoSysÆdisinfection unit, submitted in the application for

Basic Approval (MEPC 54/2/4), are based on both nominal treatment conditions as well as

worst-case disinfection scenarios and regarded as having an overall higher impact on the water

due to the lack of proper pre-filtering etc. This was also confirmed by the following tests with the

complete full-scale CleanBallast! system, where the acute toxicity tests showed less toxic effect, compared to the disinfection unit alone. During the tests, the Active Substance responsible for the

toxicity was also used in a maximum worst-case quantity rather than nominal in ballast water

treatment (see section 3.7). Chronic toxicity data on worst-case effluents from the disinfection

unit alone without degradation of the substances judged as responsible for the potential toxic

effect (TRO, DBPs) shows no effect at concentrations relevant to the receiving environment after

discharge (see section 3.7.2). Realistically, computer-simulated emission scenarios, both generic

cases and case studies, together with actual field measurements confirm that organisms in

receiving environments will not suffer any toxicological stress due to the use of CleanBallast!

system (see section 3.8).

4.4 Conclusion

Analysis results ñ combined with toxicity data, degradation data/predictions and risk assessment ñ show that, even if high safety factors are applied, the applicant assessed that no harm will be

done to the surrounding environment, ship or crew using the CleanBallast! system. However, since certain toxicity, specified in this document, was found in the effluent water; it

might be considered necessary to assess this local immediate marine environmental impact

against the potentially catastrophic environmental impact of introducing alien species into new

biotopes. The WHO type of risk/benefit analysis can be used based on the Convention on

Biological Diversity (CBD), Article 14. The GESAMP-BWWG is invited to give their view of

this conclusion, and also to continue assessment of the overall used worst-case approach, the

relevancy and quality of performed tests in this document.
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5 ASSESSMENT REPORT (G9, 4.3)

5.1 Quality of test reports

5.1.1 Whole-effluent toxicity studies

The whole-effluent tests and analysis on acute toxicity for the EctoSysÆdisinfection unit alone, submitted in the application for Basic Approval (MEPC 55/2/4), have been performed by

certified laboratories accredited to GLP and experienced personnel. The chronic whole-effluent

toxicity tests, included in this application for Final Approval, have also been performed by the

same certified laboratory with the correct expertise. The whole-effluent acute toxicity studies on

water sampled from the land-based type approval process have been performed by accredited

laboratory and additionally supplemented with custom-made kinetic toxicity studies and relevant

measurements to be able to analyse the immediate toxicity after treatment as well as monitor the

initial time period thereafter, where the toxicity rapidly fades out. These custom-made tests have

been developed from standard toxicity procedures, using well-known test species and have been

conducted by relevant expertise in toxicology.

5.1.2 Whole-effluent characterization

A chemical characterization of the whole effluent including sludge was carried out according to

the Methodology. The external analyses were made at certified laboratories, and the on-site

measurements were done by experienced personnel using methods and material including quality

management acknowledged by the national administration of Germany.

5.1.3 Analysis of disinfection by-products (DBPs)

The sampling and sending samples for DBP analysis were done in accordance with generally

accepted methodologies and according to instructions given by accredited laboratories doing the

analysis. The analysis of disinfection by-products (DBPs) has been done at accredited laboratories

in accordance with standard test protocols (e.g., DIN etc.). The exception is the bromate analysis, where a specially developed laboratory method (based on IC-ICP-MS technique) was used, in

order to detect extremely low quantities of the substance in question without interference by high

anion (chloride) concentration.

5.1.4 Simulating emission scenarios for ballast water discharge

The computer models of ballast water discharge scenarios were performed by experienced

expertise at laboratory accredited to GLP, having developed customized computer models before

for other emission scenarios of chemicals into receiving waters.

5.2 Assessment of the risk characterization

The whole-effluent tests and analysis on toxicity for the EctoSysÆdisinfection unit, submitted in

the application for Basic Approval (MEPC 54/2/4), are based on both nominal treatment

conditions as well as worst-case disinfection scenarios and regarded as having an overall higher

impact on the water due to the lack of proper pre-filtering etc. This was also confirmed by the

following tests with the complete CleanBallast! system, where the acute toxicity tests showed

less toxic effect, compared to the disinfection unit alone. During the tests, the Active Substance
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responsible for the toxicity was also used in a maximum worst-case quantity rather than nominal

for ballast water treatment.

Analysis results ñ combined with toxicity data, degradation data/predictions and risk assessment ñ show that, even if high safety factors are applied, the applicant assessed that no harm will be

done to the surrounding environment, ship or crew using the CleanBallast! system. Thus, the

applicant assessed the risk characterization to be complete. The GESAMP- BWWG is invited to

give their opinion of this, and to take action as appropriate.

5.3 Consideration of uncertainty associated with the assessment (G9, 6.4.3)

The quantitative and qualitative formation of the Active Substances and Relevant Chemicals has

been thoroughly investigated according to the Procedure (G9). The whole-effluent acute- and

chronic toxicity has been thoroughly investigated taking a conservative worst-case approach to

shipboard use of the CleanBallast! system. The tests have been performed in full-scale

(500 m

3

/h) in natural waters covering the whole salinity range. The effluent discharge and

dilution into different generic- and specific case-study based receiving environments have been

modelled and verified as above worstñcase in real use.

The applicant assessed that these measures at present day covers the uncertainties raised by the

GESAMP-BWWG during their evaluation of the application for Basic Approval. Thus also, the

uncertainties of the assessment included in the MEPC 55/2/4 (mainly linked to possible

up-scaling problems, while the data given in the document were based on small-scale pilot

systems) have been fully investigated and are considered to be cleared. Possible uncertainties

with this assessment might be linked to future changes/disturbances of external parameters, such

as major changes of natural water quality e.g., by global climate change, future unforeseen

harbour types, synergistic effects with other ballast water treatment techniques using Active

Substances unknown at present day, etc. The GESAMP-BWWG is invited to give their view of

this, and to continue assessment of the nominal and worst-case approach and the relevancy and

quality of performed tests in this document.

6 REFERENCES

ìBasic Approval of Active Substances used by EctoSysô electrochemical systemî

(MEPC55/2/4), Submitted by Sweden. Allonier A.-S., Khalanski M., Camel V. and Bermond A. (1999): Characterization of chlorination

by-products in cooling effluents of coastal nuclear power stations. Marine Pollution Bulletin, Vol. 38, No. 12, pp. 1232 ñ 1241. Batterman S. et. al. ìPartition coefficients for the trihalomethanes among blood, urine, water, milk and airî The Science of the Total Environment 284, p. 237-247 (2002). BMT Fleet Technology Ltd. ìDeterioration of structural integrity due to chemical treatment of

ballast waterî, 311 Legget Drive, Kanata, ON K2K 1Z8. Chu I., Secours V., Marino I. and Villeneuve D. C. ìThe Acute Toxicity of Four Trihalomethanes

in Male and Female Ratsî Toxicol. Appl. Pharmacol. 52, 351-353. (1980). Cooper W. J., Jones A. C., Whitehead R. F. and Zika R. G. (2007): ìSunlight-induced

photochemical decay of oxidants in natural waters: Implementation in ballast water treatmentî. Environ. Sci. Technol. 41, 3728 ñ 3733.
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Crane A.M., Erickson S. J. and Hawkin C. E. (1980): Contribution of marine algae to trihalomethane

production in chlorinated estuarine water. Estuarine and Coastal Marine Science 11, 239 - 249. Dalvi A. G., Al-Rasheed R. and Javeed M.A. (2000): Haloacetic acids (HAAs) formation in

desalination processes from disinfectants. Desalination 129, 261 ñ 271. EPA (2006): Environmental Protection Aagency ìNational Primary Drinking Water Regulations:

Stage 2 Disinfectants and disinfection By-products Rule; Final ruleî Federal Register, Vol. 71, No.2 (2006). Fabbricino M. and Korshin G. V. (2005): Formation of disinfection by-products and applicability

of differential absorbance spectroscopy to monitor halogenation in chlorinated coastal and deep

ocean seawater. Desalination 176, 57 - 69. Fawell J. ìRisk Assessment Case Study-Chloroform and Related Substancesî Food and

Chemical Toxicology 38. p.91-95 (2000). Franklin M. J., Nivens D. E., Vass A. A, Mittelman M. W., Jack R. F., Dowling N. J. E. and

White D. C. ìEffect of chlorine and chlorine/bromide biocide treatments on the number and

activity of biofilm bacteria and on carbon steel corrosion,î Corrosion vol. 47, p.128-134 (1991). HÂkansson, Bo et. al. ìElectrolytic cell for treating contaminated watersî, Patent application no.:

WO2005058761(A1). Hanson et.al. (2004) ìHaloacetic acids in the aquatic environment. Part I: macrophyte toxicityî Environmental Pollution 130, p.371-383. Hanson et.al. (2004) ìHaloacetic acids in the aquatic environment. Part II: ecological risk

assessmentî Environmental Pollution 130, p.385-401. Hill G. C. (2003): 4. Microbial problems in bilge and ballast. In: Hill E. C. (Ed.): Microbes in the

marine industry. IMarEST Publications. Hutchinson, Thomas H. et. al. ìA Review of the Effects of Bromate on Aquatic Organisms and

Toxicity of Bromate to Oyster (Crassostrea gigas) Embryosî Ecotoxicology and Environmental

Safety 38, 238ñ243 (1997). Nokes C. J., Fenton E. and Randall C. J. (1999): Modelling the formation of brominated

trihalomethanes in chlorinated drinking waters. Water Research, Vol. 33, No.17, 3557-3568. Pavelic P., Nicholson B. C., Dillon P. J. And Barry K.E. (2005): Fate of disinfection by-products

in groundwater during aquifer storage and recovery with reclaimed water. Journal of

Contaminant Hydrology 77, 119 ñ 141. Rodriguez M. J., Serodes J. Ad Roy D. (2007): Formation and fate of haloacetic acids (HAAs)

within the water treatment plant. Water Research, in press, doi:10.1016/j.watres.2007.05.048S. Sundstrˆm J., CollÈn J., Abrahamsson K. and PedersÈn M. (1996): Halocarbon production and in

vivo brominating activity of EUCHEUMA DENTICULATUM. Phytochemistry Vol. 42, No.6, pp. 1527 ñ 1530. US EPA (1999): Alternative Disinfectants and Oxidants Guidance Manual. EPA 815-R-99-014, April 1999. Von Gunten U. and Oliveras Y. (1998): Advanced oxidation of bromide-containing waters:

Bromate formation mechanisms. Environ. Sci. Technol., 32(1), 63 - 70. WHO 2005: ìTrihalomethanes in Drinking-Waterî Background document for development of ìWHO Guidelines for Drinking-Water Qualityî, WHO/SDE/WSH (2005).
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Wong G. T. F., Davidson J. A. (1977) ìThe fate of chlorine in sea-waterî Water Research

Vol. 11, pp. 971 - 978. Wu W. W. and Chadik P. A. (1998): Effect of bromine ion on haloacetic acid formation during

chlorination of Briscayne aquifer water. Journal of Environmental Engineering, October 1998, 932 ñ 938.

7 ABBREVIATIONS

AOX: Absorbable Organic halogens

BPD: Biocidal Products Directive

BWT: Ballast Water Treatment

CBD: Convention on Biological Diversity

CPO: Chlorine Produced Oxidants

DB: Deballasting

DBP: Disinfection By-products

DP: Discharge Point

DOC: Dissolved organic carbon

FAC: Free Active Chlorine

GLP: Good Laboratory Practice

HAA: Haloacetic acids

LBTA: Land-based type approval

NOEC: No Observable Effect Concentration

NOM: Naturally present Organic Matter

PEC: Predicted Environmental Concentration

PNEC: Predicted No Effect Concentration

POC: Particular organic carbon

ROS: Reactive Oxidative Species

TAC: Total Active Chlorine

TGD: European Commission Technical Guidance Document on Risk Assessment

(EU-TGD, EC 2003)

(T)THM: (Total) Trihalomethanes

TOC: Total Organic Carbon

TRC: Total Residual Chlorine

TRO: Total Residual Oxidants

TSS: Total Suspended Solids

____________