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

I:\MEPC\58\2-1.doc

INTERNATIONAL MARITIME ORGANIZATION

IMO 

# E

MARINE ENVIRONMENT PROTECTION
COMMITTEE
58th session Agenda item 2 MEPC 58/2/1
19 March 2008 Original: ENGLISH

HARMFUL AQUATIC ORGANI SMS IN BALLAST WATER

Application for Final Approval of the OceanSaver Æ Ballast Water Management System (OS BWMS)

Submitted by Norway

SUMMARY

Executive summary: This document contains non-confiden tial information related to the application for Final Approval of the OceanSaverÆ Ballast Water Management System in accordance with the Procedure for approval of ballast water management systems that make use of Active Substances (G9) adopted by resolution MEPC.126(53)

Strategic direction: 7.1

High-level action: 7.1.2

Planned output: 7.1.2.4

Action to be taken: Paragraph 6

Related document: BWM/CONF/36, MEPC 53/24/Add.1, MEPC 57/2/6, MEPC 57/2/10
and BWM.2/Circ.12

Introduction

1 Regulation D-3.2 of the International Conve ntion for the Control and Management of Shipsí Ballast Water and Sediments stipulates th at ballast water management systems that make use of Active Substances to comply with the Convention shall be appr oved by the Organization.

2 The Procedure for approval of ballast water management systems that make use of Active Substances (G9) identifie s the information that should be incl uded into a proposal for approval (MEPC 53/24/Add.1, annex 4, paragraph 4.2.1) and provisions for risk characterization and analysis (MEPC 53/24/Add.1, annex 4, paragr aph 5.3). According to section 6 of Procedure (G9), the Organization should evaluate the informati on provided in the application.MEPC 58/2/1 - 2 -

I:\MEPC\58\2-1.doc 3 According to BWM.2/Circ.12, a document on the proposal for approva l containing all the
non-confidential data related to the respective ballast water mana gement systems that make use
of Active Substances needs to be submitted to MEPC 58.

4 The competent authority in Norway has verifi ed the application dossi er and believes that it satisfies the data require ments of Procedure (G9).

5 Norway therefore submits the non-confidentia l part of the manufacturerís application dossier, as set out at the annex to this documen t, to the Organization for evaluation according to Procedure (G9). The complete dossier will be made available to the experts of the
GESAMP-BWWG with th e understanding of conf idential treatment.

Action requested of the Committee

6 The Committee is invited to consider the pr oposal for approval and decide as appropriate.

***MEPC 58/2/1

I:\MEPC\58\2-1.doc ANNEX

NON-CONFIDENTIAL INFORMATION ON THE OCEANSAVERÆ BALLAST WATER MANAGEMENT SYSTEM (NORWAY)

Contents

1 INTRODUCTION

2 OVERVIEW OF THE OCEANSAVERÆ BWMS

2.1 OceanSaverÆ Ballast Water Management System ñ treat sequence 2.2 Ship system interface implications 2.2.1 Operational implications

3 OVERVIEW OF THE INFORMATIO N BASIS FOR THE APPLICATION

3.1 Land-based tests for approval of the BWMS (G8)

4 ACTIVE SUBSTANCES

4.1 Identification of Active Substances 4.2 Active Substance decay

5 RELEVANT CHEMICALS

6 DATA-SET FOR ACTIVE SUBSTANC ES AND RELEVANT CHEMICALS

7 ECOTOXICOLOGICAL RESPONSES OF TREATED BALLAST WATER

7.1 Introduction 7.2 Growth inhibition of the marine algae Skeletonema Costatum 7.3 Invertebrate toxicity testing 7.4 Fish toxicity testing 7.5 Summary and conclusion with regard to ecotoxicity

8 ENVIRONMENTAL RISK ASSESSMEN T ñ BALLAST WATER DISCHARGE

8.1 PNEC evaluation based on toxicity te sting of treated ballast water
8.2 Environmental risk assessment applying the MAMPEC Model
8.3 SINTEF - environmental risk assessment in two harbours 8.4 Risk assessment - discharge of hypoxic ballast water
8.5 Conclusion - environmental risk assessmentMEPC 58/2/1
ANNEX Page 2

I:\MEPC\58\2-1.doc 9 HUMAN EXPOSURE ASSESSMENT

9.1 Introduction 9.2 Risk characterization during normal operation
9.2.1 Risk characterization for th e operator during ballasting
9.2.2 Risk characterization for the crew a nd general public during ballasting 9.2.3 Risk characterization for the operator and crew during discharge of ballast water 9.2.4 Risk characterization for the general public during discharge of ballast water 9.3 Risk characterization during maintenance
9.3.1 Maintenance of the C2E unit
9.3.2 Maintenance of the ballast water tanks
9.4 Risk characterization in accident situations

10 CORROSION

10.1 Introduction 10.2 Testing
10.3 Results
10.4 The addition of the C2E disinfectants

1 INTRODUCTION

This report contains the non-c onfidential information concerning the OceanSaverÆ Ballast Water Management System (OS BWMS) and is struct ured in accordance with the Procedure for approval of ballast water management systems that make use of Active Substances (G9).

The application for Final Approval submitted to IMO consists of two parts:

ñ a summary document containing non-confidential information submitted by the Member to MEPC (this document); and

ñ a full and comprehensive application dossier submitted to the IMO secretariat accompanied by a complete set of annexes containing reports, assessments and
confidential information a bout the OceanSaverÆ BWMS.

Besides covering the requirements of Proce dure (G9) and the GESA MP-BWWG Methodology, the application also includes information mee ting the recommendations a nd requests provided by the GESAMP-BWWG in the report of its fift h meeting (MEPC 57/2/10), recommending that Basic Approval to be granted the OS BWMS . The GESAMP BWWG co mments are listed below
with a reference to the section in this docum ent containing information relevant to the

comments:

1 ìThe application indicates that the sequenc e of the different treatment elements may be varied. In any application for Final Approval, the Group would require a definite configuration to be submitted for evaluation.î (section 2);

2 ìWhere the use of Nitrogen is concer ned, the Group considers that high nitrogen levels and consequent oxygen depletion in the headspace of ballast tanks could form a hazard to human health and that de oxygenated ballast water could form a hazard to the environment unless adequatel y oxygenated prior to discharge of
ballast water.î (sections 8 and 9);MEPC 58/2/1
ANNEX

Page 3

I:\MEPC\58\2-1.doc 3 ìThe applicant claims that TRO had dis appeared in less than 24 h. However, it requires explanation why the ecotoxicity te sts carried out all showed ecotoxicity even 5 days after treatment.î (sections 4 and 7);

4 ìThe Group expects that the applicant will provide a co mplete environmental risk assessment as part of an applic ation for Final Approval.î (section 8);

5 ìThe Group considered that the mitigation steps included in the application i.e. re-aeration prior to discharge would be an important factor, in reducing the discharge concentrations of a variet y of Active Substances and by-products.î (section 8);

6 ìTaking the above into consideration, the Group recommends that for Final Approval, the Applicant should subm it the BWTS HES, namely to address nitrogen exposure as here is an identifie d risk in several areas adjacent to a nitrogen-filled space.î (section 9);

7 ìThe Group recommends that for Final A pproval description of the operation units where human exposure can take place should be submitted according to HES (MEPC 56/2/2, annex 9). The Group r ecommended that for Final Approval, the Applicant should submit a BWTS HES, where unit operations for the nitrogen system and electrochemical system are de scribed in terms of where, when and how human exposure can take place (ple ase see HES, MEPC 56/2/2, annex 9).î (section 9); and

8 ìThe Group noted that no corrosion tests were carried out with the complete OceanSaverÆ treated ballast water, wh ich would include electrochemical
activation and cavitation.î (section 10).

2 OVERVIEW OF THE OceanSaverÆ BWMS

The OceanSaverÆ Ballast Water Management Sy stem (OS BWMS) applies cavitation, nitrogen supersaturation and disinfection as main work ing principles following a pre-filtration step.

The OS BWMS consists of several components which may be categoriz ed as both ancillary components and as OceanSaverÆ components. The ancillary components are industrial type equipment developed for the maritime industry, and are applied on board ships for various purposes worldwide. For these components the OS BWMS is not committed to use a singular manufacturer or a specific com ponent, but rather it is more pertinent to specify equipment performance characteristics and deliverables. The OceanSaverÆ components on the other hand are specifically developed and designed for the OS BWMS and thus require a more in-depth specification.MEPC 58/2/1
ANNEX Page 4

I:\MEPC\58\2-1.doc The OS BWMS treatment sequence is fixed a nd illustrated in Figure 1 below and further elaborated upon in the following text.

Figure 1: The OS BWMS: Main Components

2.1 OceanSaverÆ Ballast Water Manageme nt System ñ treatment sequence

On ballast uptake, following the ballast water pump, the water enters a mechanical filtration unit to remove particles and organi sms. The filter includes automatic back flushing, which removes the larger trapped particles and organisms and thus contributes in protecting the remaining treatment components and at the same time c ontributes to the reduction of accumulated
sediments in the ballast water tanks.

Following filtration, the ballast water is subjected to controlled intense pressure pulses arising from hydrodynamic cavitation. In the OS BWMS, th e cavitation is generated in a specially developed circumferential cavitation chamber (the C3T unit), which operates over a flow rate and differential pressure range with the aid of eith er active or passive ba ck pressure controls (depending on the overall configurat ion of the specific ballast wate r system including the ballast water tanks). Harnessed in this way, these pre ssure pulses are intense enough to rupture cell membranes and destroy particles and organisms by forcing them to ruptur e, collapse or collide
with one another. In order to achieve desired fl ow rate capacities, the C3T unit is stacked with identical C3T sub-units, duplicated and arranged along a circumference and integrated in the actual ballast water pipe in a manner providing identical flow conditions and thus identical efficacy for each individual sub-unit.MEPC 58/2/1
ANNEX

Page 5

I:\MEPC\58\2-1.doc Following exposure to cavit ation, the ballast water is then supersaturated by the injection of nitrogen before it enters the vesselís ballast water tanks. Nitr ogen supersaturation causes oxygen naturally dissolved in the water to be released, leaving the water in the tanks deficient in oxygen (in a hypoxic condition) and thus, severely affec ting residual organisms that are dependent on oxygen for their survival. The released oxygen and su rplus nitrogen is evacuated by the use of conventional tank ventilation arrangements. In order to avoid further natural release of the nitrogen over time and to prevent potential contam ination by outside air en tering the ventilation system a pressure-vacuum device is incorporated into the ventilation system of the ballast water tanks (the vent-head) to maintain and allow control of optimum satu ration levels during a

voyage.

Additionally, in order to ensure compliant e fficacy as a function of varying ballast water properties, the system also incorporates an isolat ed electrodialytic proces s based on the principles
of an electrochemical activati on technology, the C2E process. The C2E unit applies the principle
of electrochemical activ ation to a small portion of the flow , producing a disinfectant which is returned to the main flow following cavit ation (C3T) exposure in conjunction with supersaturation in order to enhance the overall biological efficacy. The C2E unit does this by generating controlled amounts and variations of Active Substances in situ wit hout adding any Preparations to the water. A feature of the proc ess is that these activat ed substances naturally degrade over a relative short period of time. Furthe r, the efficacy of the disinfectant is enhanced by cavitation since the cavitation causes fragmentat ion and separation of b acterial colonies etc., which expose organisms previously protected by the surrounding colony to the disinfectant, thereby, creating a significant increase in biologi cal efficacy at modest dosage and concentration levels. To meet necessary range of flow rates, the C2E unit is modularly composed and consists of a number of identical cells powered by a number of iden tical rectifiers.

During ballast water discharge, the ballast water pump pumps the ballast water from the respective ballast water tanks. In this mode, the water is e xposed to cavitation (C3T) only.

2.2 Ship system interface implications

The introduction of ballast water treatment, regard less of measure or measures applied, is most likely to have impacts that may introduce requireme nts to other on board ship systems. Analysis of the OS BWMS has identified such implications:

ñ existing or conventional approaches to supply system (pump, piping and distribution);

ñ automation, control a nd monitoring; and

ñ corrosion and potential coating degradation.

The generation of hydrodynamic cavitation introduces additional pressure losses to the overall ballast water system when compared to conventio nal non-treatment ballast water systems. This is taken into account by including th e pressure losses generated in total by the system including the C3T unit when specifying the ballast wate r pump requirements. For some vessels this requirement may introduce an additional boosti ng pump instead of an upgrade of the actual ballast water pump specification. Note that an increased system pressure may impact piping arrangements as this may be specified to a dive rging design pressure sp ecification. This is an issue arising when considering the installation of the OS BWMS on bo ard an existing vessel. For new vessels, this issue will have been addressed in the system requirement specification.MEPC 58/2/1
ANNEX Page 6

I:\MEPC\58\2-1.doc The extent of on-board automation may vary c onsiderably from one vessel to another and consequently representing a considerable cha llenge in relation to interface flexibility. The OS BWMS has an internal automation, calibrati on and data monitoring, storage and reporting system. This administrates and controls overall performance between all components/processes within the system and records all measured data . This allows the OS BWMS to operate with simplified interfaces limited to the vessels ballast water pump and distribution. The system includes recording and storage of data in accordan ce with the requirements as specified in the Guidelines for approval of ballast water management systems (G8).

Comprehensive corrosion and coating impact studies including literature assessments, small-scale and laboratory studies as well as fu ll-scale studies have been conducted. The main objectives of these studies have been to verify that the OS BWMS does not accelerate corrosion nor the ageing of corrosion protection systems (coa tings) and also that the system is compliant
with the intentions of Performan ce standard for protective coatings for dedicated seawater ballast tanks in all types of ships and double-side skin spaces of bulk carriers adopted by resolution MSC.215(82). It may be noted that the fu ll-scale studies include d all treatment stages with the exception of the addition of th e disinfectants produced by the C2E unit (filtration, cavitation and supersaturation). An additional study has since been undertaken including this treatment stage. Results from th ese studies are further discussed in section 10.

2.2.1 Operational implications

The performance of the C2E component in th e OS BWMS depends upon the use of saline seawater or alternatively a brine solution. Th e electrochemical activation process will operate satisfactorily with a level of s eawater salinity of 0.7% and above. In cases wh ere the ballast water taken on board has a level of salinity below this poi nt, measures are installed to ensure that the saline level in the feed water to the unit remains within satisfactory levels.

The electrochemical activation technology applie d within the C2E unit will generate a limited quantity of hydrogen (H 2 ). Since hydrogen is a flammable ga s which may also be explosive under certain conditions, this naturally raises various concerns. These concerns have been comprehensively addressed in a separate study in cluding theoretical consid erations verified by field test programs. The study has addressed potential accumul ation of hydrogen at dangerous levels in spaces as applicable (C2E location, en gine room, ballast water pipe line, ballast water tanks, etc.). Based on this study, a safe gas evacuation system has been specified and developed. The system rests upon the principles of collection at source, dilution by air to safe concentration levels and evacuation to open air.

Hydrogen is flammable at concentr ations of 4% and explosive at levels above 18%. The safe gas evacuation system includes continuous dilution to less than 1%. Safety features are employed to
ensure reliable colle ction at source, continuous dilution an d evacuation. The approach on safe gas
evacuation as identified for the OS BWMS has b een benchmarked with approaches implemented for other systems on board ships producing H 2 (e.g. electrochemical bio- fouling units for cooling systems, battery charge stations, etc.).MEPC 58/2/1
ANNEX

Page 7

I:\MEPC\58\2-1.doc 3 OVERVIEW OF THE INFORMATIO N BASIS FOR THE APPLICATION

The system has been the subject of continuous performance assessments and development for a duration accumulating to more than 5 years. This has incorporated:

ñ initial small-scale laboratory studies (flow rates flow < 5 m 3 /h) at the DNV
laboratories (2003 ñ 2004);

ñ small- and medium-sca le (flow rates < 40 m 3 /h) land-based tests at the MetaFil laboratory at Fagerstran d from May 2005 to March 2008;

ñ the OS BWMS te st unit of 200 m 3 /hr capacity (operati onal range: 190ñ250 m 3 /hrs).
This was commissioned in Ju ne 2007. Compliant land-bas ed testing in accordance with the IMO Guidelines (G8)/Procedure (G9) started in August 2007 at NIVAís facility at Solbergstrand, Norway. The co mpliance tests in Guidelines (G8 )were successfully finished in November 2007;

ñ endurance tests (OS BWMS 200 m 3 / hrs test unit) test unit (January 2008 and ongoing);

ñ the development proc ess has incorporated two prototype ship installations which are used actively as research platforms. A fu ll installation of the OS BWMS is now on
board the MV Hˆegh Trooper . A total of two full-sc ale corrosion studies (DNV/ Safinah Ltd.) an d 18 on-board biologic al efficacy studies have been carried out (University of Bergen (UNIFOB)/GoC onsult) including tw o approval tests (shipboard testin g) under Guidelines (G8);

ñ parallel laboratory assessments of corros ion control and coati ng impact studies in compliance with DNVís respective standards (DNV/ Safinah Ltd.).

ñ consequential analysis addr essing the potential impacts of the incl usion of the C2E treatment step to the overall coating/ corrosion achievement s by the remaining treatment stages (nitrogen supersatura tion and consequentia l oxygen reduction. (Safinah Ltd.);

ñ environmental Risk Assessment (in accordan ce with Guidelines (G8)/Procedure (G9) (DNV/ NIVA/ Sintef);

ñ installation studies includin g vibration analysis (StoGd a sp.zo.o Ship Design and Engineering (Poland));

ñ testing of a data recording and monitori ng system for functiona lity control of the treatment system under the EU CRAFT Programme (OceanSaver Ballast Water treatment) (Pole Star Ltd./Houm as/MAS as /Technological Institut e of Norway (TI);

ñ the development of a singular platform fo r system automation, calibration and data recording, processing and storage (Batronic AS);

ñ safety assessment associ ated with gas production by electrolysis; production, separation dilution and removal (IGAGIC (UK)/ GexCon as);MEPC 58/2/1
ANNEX Page 8

I:\MEPC\58\2-1.doc ñ a study of the efficacy of filtration under dirty load situations. The initial filtration test
was undertaken in 2005 at the resear ch facility of NIOZ, the Netherlands (DNV/NIOZ);

ñ industrialization ñ feasibility assessments looking at improvements with focus on sampling, system interactio ns including shipboard auto mation, installation and
maintenance issues etc. For this, the vesselís crew has been engaged in order to attain experience feedback to be used in the process of industrialization;

ñ conceptual feasibility st udies regarding OS BWMS onboard; chemical carriers (including product carriers/LNG carriers/crude oil carriers/bulk carriers (larger class).
These studies were unde rtaken by DNV; and

ñ human exposure assessment.

3.1 Land-based tests for approval of the BWMS (G8)

The tests were conducted at NIVAís test site lo cated at Solbergstrand, 20 km south of Oslo. Seawater is supplied from vari ous depths down to 60 m in the Oslofjord, while fresh water is supplied from ground water bore holes or from a local creek.

The test facility includes 4 glass-fibre reinforced polyester tanks, supplied with inlet and outlet arrangements and equipment for proper cleanin g. The three tanks for st orage are covered to mimic real conventional ballast tank conditions, e.g. preventing light introduction and limiting air exchange. The surfaces of the test tanks (TT1 and TT2) and the control tank (CT1) are coated with coatings widely applie d for ships ballast tanks (Ba lloxy HB light, Jotun, Norway).

Figure 2: Transfer of test water during one test cycle with the OS BWMS including a test line (blue) and a control line (red). Sampling numbe rs are indicated by S1-S5. Note that nitrogen supersaturation is not included in th e illustration for purposes of clarity.

The different water transfers between tanks via the OS BWMS during a test cycle including the control, is shown in Figure 2. One test cycle (blue lines) includes the consecutive treatment
of >200 m 3 test water by the OS BWMS (including filter, C3T cavitation, C2E disinfectants as WST
516 m 3 S2

TT1
231 m 3

S5 C3T TT2
205 m 3

CT2
205 m 3 S1 S3

S4 filter Pump C3T cavitation unit
C2E electrodial y tic unit

C2EMEPC 58/2/1
ANNEX

Page 9

I:\MEPC\58\2-1.doc well as nitrogen injection for supersaturation), tran sferring the test water from tank with prepared test water (WST) to a ballast water tank (TT1). The treated water is stored in TT1 for a minimum of 5 days. After 5 days, the wa ter is transferred by the feed pump, ballast pump and the booster pump, by-passing the filter and the C2E unit, but treated in the C3T unit, to TT2 for sampling before discharge. Note that discharge doe s not involve the use of C2E nor nitrogen supersaturation. Tank ventilation management by means of pressure/vac uum valve control is fitted on the tank (TT1) simulating the vessels ballas t tank ventilation arrangement as specified in
the OS BWMS.

A control cycle (red lines) is run by transferring >200 m 3 of the same type of prepared test water from WST to a ballast tank (CT2) for at least 5 days storage using the pump of the OS BWMS, but in by-pass of the treatment units. After stor age the control water is pumped to TT1 for sampling before discharge.

An overview of the relevant analysis of disi nfection by-products (DBP) and ecotoxicity tests
done with water treated in the land-based tests unde r Guidelines (G8) is pr esented in Table 3-1. Note that in addition, results from similar analys is (DBP and ecotoxicity tests) from a pre-test with medium salinity carried ou t in June 2007 were presented in the application for Basic Approval.MEPC 58/2/1
ANNEX Page 10

I:\MEPC\58\2-1.doc Table 3-1 Overview of ecotoxicity tests and di sinfection by-product an alysis carried out in
the land-based tests in accord ance with Guidelines (G8)

Test cycle Date Salinity
PSU TSS, mg/L DOC, mg/L POC, mg/L Samples/Analysis

1 8-13th Aug 07 > 32 15.7 2.2 3.3

2 15-20th Aug 07 > 32 15.3 2.2 3.0 Ecotoxicity-Skel (Day 5) Ecotoxicity- Acute Turbot (day 5) Ecotoxicity ñ Chronic turbot ñ 1 (day 5)

3 22-27th Aug 07 > 32 13.0 2.8 2.6 Ecotoxicity-Skel (Day 0, 5) Ecotoxicity-Nitocera (day 5) Ecotoxicity ñ Chronic turbot ñ 1 (day 5)

4 29thAug3th Sep
07 > 32 10.8 3.0 3.1 Ecotoxicity-Skel (Day 0, 5) Ecotoxicity-Nitocera (day 5) Ecotoxicity ñ Chronic turbot ñ 1 (day 5)

5 5-10 th Sept 07 > 32 76.2 2.6 2.9 By-products (day 0, 5) Ecotoxicity-Skel (Day 0, 2, 5) Ecotoxicity-Acartia (day 5) Ecotoxicity ñ Chronic turbot ñ 1 (day 5)

6 12-17 th Sept 07 < 22 69.5 8.9 11.6 Ecotoxicity-Skel (Day 0, 5)

7 19-24 th Sept 07 < 22 67.6 8.3 11.2 By-products (day 0, 5) Ecotoxicity-Skel (Day 0, 5) Ecotoxicity-Acartia (day 5) Ecotoxicity-Nitocera (day 5) Ecotoxicity- Acute Turbot (day 5) Ecotoxicity ñ Chronic turbot ñ 2 (day 5)

8 3-8 th

Oct 07 < 22 68.5 9.9 9.9 Ecotoxicity-Skel (Day 0, 5) Ecotoxicity ñ Chronic turbot ñ 2 (day 5)

9 10-15 th

Oct 07 < 22 64.5 8.6 11.5 Ecotoxicity-Skel (Day 0) Ecotoxicity ñ Chronic turbot ñ 2 (day 5)

10 17-22 th

Oct 07 < 22 66.9 7.8 11.0 Ecotoxicity-Skel (Day 0, 5) Ecotoxicity ñ Chronic turbot ñ 2 (day 5)

11 24-29 th

Oct 07 < 22 67.9 7.6 11.0 By-products (day 0, 5) Ecotoxicity-Skel (Day 0, 2, 5) Ecotoxicity ñ Chronic turbot ñ 2 (day 5)

12 31th
Oct5 th Nov

07 < 22 81.6 9.0 12.7 By-products (day 0, 5) Ecotoxicity-Skel (Day 0) Ecotoxicity ñ Chronic turbot ñ 2 (day 5)

13 7-12 th

Nov 07 > 32 14.4 2.2 2.7 By-products (day 0, 5) Ecotoxicity-Skel (Day 0, 5)

14 14-19 th

Nov 07 < 22 76.4 8.5 10.2 By-products (day 0, 5) Ecotoxicity-Skel (Day 0, 5)

Results from these tests are presented in the following sections.MEPC 58/2/1
ANNEX Page 11

I:\MEPC\58\2-1.doc 4 ACTIVE SUBSTANCES

4.1 Identification of Active Substances

The component of the OS BWMS deemed relevant for Active Substance approval is the C2E unit (MEPC 57/2/6). Active Substances are produced in the anode chamber (anolyte, commercial reference: AWAC) and to so me extent in the cat hode chamber (catholyte, commercial reference: AWAL) of the C2E unit. The Active Substances formed in the C2E unit are primarily hypochlorous acid (HClO) with concentrations of chlorine gas (Cl 2 ), ozone (O 3 ), hydrogen peroxide (H 2 O 2 ), chlorine dioxide (ClO 2 ) and hypochlorite (ClO - ). In seawater these oxidants react with bromide (Br - ) and generate hypobromous acid and hypobromite ion. The resulting mixture of oxidants (mainly hypochlorous acid, hypochlorite ions, hypobromous acid and hypobromite ion) are named Free Residua l Oxidant (FRO) in the literature while Total Residual Oxidant (TRO) also includes the halogenamines and other less effective oxidants with N-C link. The maximum dosage of TRO in th e OS BWMS measured in the ballast water line is 2.5 mg Cl/L.

More detailed information about the Active Substa nce and properties of th e individual oxidants was submitted in the application for Basic Approval (MEPC 57/2/6) and will not be repeated in this document. In the following text the Activ e Substance will be re ferred to either as Free Residual Oxidant (FRO) or Total Residual Oxidant (TRO).

4.2 Active Substance decay

The decay of free and total residual oxidant levels has been investigated in relevant natural sea
water environment after OS BWMS treatment under simulated ballast water treatment conditions in the Oslofjord, Norway. Remaining concentrations of oxidants in the treated ballast water were
measured with standard colorimetric met hods (HACH-Lange: DPD method; SM 4500-Cl G, USEPA 330.5). Results from samples taken during th e full scale land-based tests are presented in the following figures (Figures 3 to 7).

The results show that the decay rates are very high in the first 30 minutes after injection of the disinfectants arriving from the C2 E unit. It takes approximately one hour to treat the full volume (>200 m 3 ) of test tank TT1. During this period it wa s not possible to take samples from TT1. Highest oxidant concentration measured in samp les taken from TT1 between 1 and 2 hours after filling started was around 1 mg C l/L (low salinity Tests 10 and 11, and all high salinity tests). A 50 L sample was therefore taken from the ba llast pipe for the purp ose of monitoring the oxidant decay before samples could be taken from test tank TT1. All results in the following figures from before 2 hours are from these samples.

The maximum allowable concentration of the Active Substances (Procedure (G9), paragraph 7.1.1) measured in the ballast tank after filling of tr eated water is estimated to be 2 mg Cl/L taking into account that the sea wa ter taken up by a ship may be less polluted with organic matter than used in the land-based tests.MEPC 58/2/1
ANNEX Page 12

I:\MEPC\58\2-1.doc Medium salinity - high organic concentration

0,00 0,25 0,50 0,75 1,00 1,25 1,50 1,75 2,00 2,25 2,50

0 20 40 60 80 100 120 140 160 180 200 220 240 260 280 300 320 Time (min)Free residual oxidant (mg Cl/L) Test 6 Test 7 Test 8 Test 9 Test 10 Test 11 Test 12

Figure 3: Decay of Free Residual Oxidant in tr eated water from land-based approval tests with the OS BWMS measured by the DPD method. Measur ements were done in a sample (50 L) taken out immediately after treatment. Test numbers refer to Table 3-1.

Medium salinity - high organic concentration

0,00 0,25 0,50 0,75 1,00 1,25 1,50 1,75 2,00 2,25 2,50

0 20 40 60 80 100 120 140 160 180 200 220 240 260 280 300 320 Time (min)Total residual oxidant (mg Cl/L) Test 6 Test 7 Test 8 Test 9 Test 10 Test 11 Test 12

Figure 4: Decay of Total Residual Oxidant in tr eated water from land-based approval tests with the OceanSaver BWMS measured by the DPD met hod. Measurements were done in a sample (50 L) taken out immediately after treat ment. Test numbers refer to Table 3-1

.MEPC 58/2/1
ANNEX Page 13

I:\MEPC\58\2-1.doc Medium salinity water - high organic concentration

0,00 0,25 0,50 0,75 1,00 1,25 1,50 1,75

0 2 50 500 750

1 000 1250 150 0

1 7 5 0 2 0 0 0 2250 2500 2 7 5 0 3 0 0 0 3250 3500 3 7 5 0 4 0 0 0 4250 4500 4 7 5 0 5 0 0 0 5250 5500 5 7 5 0 6 0 0 0 6250 6500 6 7 5 0 7 0 0 0 7250 7500

Time (min)Free residual oxidant (mg Cl/L) Test 6 Test 7 Test 9 Test 10 Test 11 Test 12

1 day 2 days 3 days 4 days 5 days

Figure 5: Decay of Free Residual Oxidant in treated water with medium salinity (around 22 PSU) from land-based approval tests with the OceanSaver BWMS measured by the
DPD method. Measurements from 0 to 2 hours are done in a sample (50 L) taken out immediately after treatment. Othe r measurements are from test tank TT1. Test numbers refer to
Table 3-1.

Medium salinity water - high organic concentration

0,00 0,25 0,50 0,75 1,00 1,25 1,50 1,75 2,00

0 250 500 7 5 0 100 0

1 2 50

1 5 00 175 0 2 0 00 2 2 50 250 0 2 7 50 3 0 00 325 0 3 5 00 3 7 50 400 0 4250 4 5 00 475 0 5000 5 2 50 550 0 5750 6 0 00 625 0 6 5 00 6 7 50 700 0 7 2 50 7 5 00

Time (min)Total residual oxidant (mg Cl/L) Test 6 Test 7 Test 9 Test 10 Test 11 Test 12

1 day 2 days 3 days 4 days 5 days

Figure 6: Decay of Total Residual Oxidant in treated water with medium salinity (around 22 PSU) from land-based approval tests with the OceanSaver BWMS measured by the
DPD method. Measurements from 0 to 2 hours are done in a sample (50 L) taken out immediately after treatment. Othe r measurements are from test tank TT1. Test numbers refer to
Table 3-1.MEPC 58/2/1
ANNEX Page 14

I:\MEPC\58\2-1.doc High salinity water - low organic concentration

0,00 0,25 0,50 0,75 1,00 1,25 1,50 1,75 2,00 2,25

0 2 50 500 750

1 000 1250 150 0

1 7 5 0 2 0 0 0 2250 2500 2 7 5 0 3 0 0 0 3250 3500 3 7 5 0 4 0 0 0 4250 4500 4 7 5 0 5 0 0 0 5250 5500 5 7 5 0 6 0 0 0 6250 6500 6 7 5 0 7 0 0 0 7250 7500

Time (min)Free residual oxidant (mg Cl/L) Test 1 Test 2 Test 3 Test 4 Test 5 Test 13 Test 14

1 day 2 days 3 days 4 days 5 days

Figure 7: Decay of Free Residual Oxidant in treated water with high salinity (around 33 PSU) from land-based approval tests with the O ceanSaver BWMS measured by the DPD method.
Measurements from 0 to 2 hours are done in a sample (50 L) taken out immediately after
treatment. Other measurements are from test tank TT1. Test numbers refer to Table 3-1.

Oemcke & van Leuwen (1998) states that the decay of residual oxidant (y) can be modeled by an exponential equation:

y = ce -kt

where k is the decay constant for the residual with denomination hr -1 . Higher values imply faster decay of TRO. The decay constant for tests with the OS BWMS is approximately 0.014 hrs -1

, which corresponds to TRO concentration of more than 0.1 mg/L for a maximum 10 days depending on water quality. This corresponds to decay constants found in DNV (2000) and in experimental work and literature ci ted in Oemcke & van Leuwen (1998).

The free and total residual oxidant was monitored from treatment (simulating ballasting) (day 0) to discharge of ballast water af ter 5 days. Highest oxidant concen tration measured after 5 days was 0.2 mg Cl/L. In a normal situation on board ships it may be assumed that the shortest voyages where treatment of the ballast water is required will be 24 hours. Based on the
information above the maximum allowable discharge concentra tion (Procedure (G9), paragraph 7.1.1) is 0.5 mg Cl/L.

5 RELEVANT CHEMICALS

The TRO formed in chlorinated seawater are mo re persistent than their parent compounds. However, the TRO will gradually degrade in redox-reactions with inorganic and organic matter,
with the liberation of Br - -ions and formation of halogena ted organic by-pr oducts in low concentrations (Relevant Chemicals).

These Relevant Chemicals are so-called Disinfec tion By-Products (DBPs) that are both organic and inorganic substances formed when TRO re act with naturally occu rring compounds in the water. DBPs are normally formed in reactions where organic chemicals play a major part. TheyMEPC 58/2/1
ANNEX Page 15

I:\MEPC\58\2-1.doc are called organohalogens and ar e further divided into volati le organohalogens (POX) and adsorbable organohalogens (AOX). Figure 8 (f rom Taylor, 2006) summarizes the current understanding of halogene chemistry associated with use of oxidants in seawater systems.

Figure 8: An outline of chemical reactions upon electrochlorination treatment of natural seawater (figure from Taylor 2006).

Based on literature review and preliminary analyses of ballast water treated with OS BWMS, the
main relevant chemicals were identified in th e application for Basic Approval (MEPC 57/2/6).

In the present study, treated water in several te st cycles were sampled and analysed for AOX, EOX, bromate, trihalomethanes (THMs) a nd other halogenated organic compounds. These compounds were analysed to clarify if the residual oxidants produced react with organic substances to form potentially harmful organic compounds, and in what concentrations. Results are given in Table 5-1 from one of the two di fferent laboratories used for the analysis.

As expected, the dominating halogenated organic compound, and THM, was bromoform. Bromoform was detected in concentrations up to 294 μg/l. In general, halogenated organic compounds are not acute toxic to aquatic animals in th e concentration range detected. Even the most toxic by-product, which is bromoform, has to be present in the mg-range to exhibit an acute toxic effect. Bromoform has an NOEC (No Observed Effect Concentration) for algae (the most sensitive trophic group) of ≥ 2 mg/l (Erickson and Hawkins, 1980).

Another compound of concern is Bromate, whic h was not found in any of the samples (Table 5-1). It was expected that some bromat e would be formed in the process. One should be aware of the analytical challenges the laborator ies are faced with when processing seawater samples. High salinity content may interfere with some of the analytical procedures used.MEPC 58/2/1
ANNEX Page 16

I:\MEPC\58\2-1.doc

Table 5-1 Concentration of AOX, EOX and ox idation by-products in control and treated water (day 0 and day 5) from Tests 5 and 7 (Analysis by Eurofins laboratory)

Test 5, day 0,
Treated Test 5, day 0,
Control Test 5, day 5,
Treated Test 5, day 5,
Control Test 7, day 0,
Treated Test 7, day 0,
Control Test 7, day 5,
Treated Test 7, day 5,
Control

AOX mg/l 2.9 1.63 0.84 3.74 0.64 3.48 5.04 0.75 Bromate μg/l < 0.003 < 0.003 < 0.003 < 0.003 < 0.003 < 0.003 < 0.003 < 0.003 EOX μg/l < 0.01 < 0.01 0.07 < 0.01 < 0.01 < 0.01 < 0.01 < 0.01 Trichlormethane μg/l < 0.5 < 0.5 < 0.5 < 0.5 < 0.5 < 0.5 < 0.5 < 0.5 Dibromchlormethane μg/l 4.6 < 0.5 5.5 < 0.5 17 < 0.5 15 < 0.5

Tribrommethane (Bromoform) μg/l 110 < 1 120 < 1 200 < 1 230 2.5

Dibromethane μg/l < 0.5 < 0.5 < 0.5 < 0.5 < 0.5 < 0.5 < 0.5 < 0.5 Dichlorbrommethane μg/l 0.51 < 0.5 < 0.5 < 0.5 0.93 < 0.5 1 2.6 1,2,3-Trichlorpropane μg/l 2.5 2.1 2.3 4.1 2.2 2.6 1.5 1.5 1,2-Dibrom-3- Chlorpropane μg/l < 1 < 1 < 1 < 1 < 1 < 1 < 1 < 1

Phenol 2-Chlorphenol μg/l < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 3-Chlorphenol μg/l < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 4-Chlorphenol μg/l < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 2,3-Dichlorphenol μg/l < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 2,4-Dichlorphenol μg/l < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 2,5-Dichlorphenol μg/l < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 2,6-Dichlorphenol μg/l < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 3,4-Dichlorphenol μg/l < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 3,5-Dichlorphenol μg/l < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 2,3,4-Trichlorphenol μg/l < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 2,3,5-Trichlorphenol μg/l < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 2,3,6-Trichlorphenol μg/l < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 2,4,5-Trichlorphenol μg/l < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 2,4,6-Trichlorphenol μg/l < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 3,4,5-Trichlorphenol μg/l < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 2,3,4,5- Tetrachlorphenol μg/l < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 < 0.1

2,3,4,6- Tetrachlorphenol μg/l < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 < 0.1

2,3,5,6- Tetrachlorphenol μg/l < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 < 0.1

PCP μg/l < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 2-Chlortoluol μg/l < 0.5 < 0.5 < 0.5 < 0.5 < 0.5 < 0.5 < 0.5 < 0.5 4-Chlortoluol μg/l < 0.5 < 0.5 < 0.5 < 0.5 < 0.5 < 0.5 < 0.5 < 0.5 1,2,4-Tribrombenzol μg/l < 0.5 < 0.5 < 0.5 < 0.5 < 0.5 < 0.5 < 0.5 < 0.5 1,3,5-Tribrombenzol μg/l < 0.5 < 0.5 < 0.5 < 0.5 < 0.5 < 0.5 < 0.5 < 0.5MEPC 58/2/1
ANNEX Page 17

I:\MEPC\58\2-1.doc 6 DATA-SET FOR ACTIVE SUBSTANC ES AND RELEVANT CHEMICALS

This information was submitted in the applicat ion for Basic Approval (MEPC 57/2/6) and will not be repeated here.

7 ECOTOXICOLOGICAL RESPONSES OF TREATED BALLAST WATER

7.1 Introduction

The IMO regulations require that treated ballast water as a mi nimum be toxicity tested both acutely and chronically at three trophic levels. Although not required in Procedure (G9), a full test program with acute and chr onic ecotoxicity at all three trophic levels has been performed for both water qualities tested and in nearly all la nd-based tests carried out as part of approval procedure under Guidelines (G8). As control, non- treated ballast water has been used to ensure that only the effect of the treat ment system is assessed. The test s and test results are summarized
below.

7.2 Growth inhibition of the marine algae Skeletonema costatum

Pre-tests showed that th e toxicity tests with S. costatum were the most sensitive endpoint. It was therefore decided that this test should be perf ormed both at 0 day and at 5 day treated water. As both absolute amount of anolyte (AWAC) and amount of organic matter varied somewhat in each test, it was of interest to have a measure of variability in toxicity. Using the results of the algal inhibition test results, it was possible to monitor the variability in biological active levels of anolyte and degradation produc ts with toxic potential.

The algae growth inhibition tests were carried out in a concentration series of 0-100% of the
treated ballast water diluted in untreated ballast water from the same batch. To all samples, an inorganic nutrient solution was added to allow un restricted, exponential grow th of the added test algae for three days. The results of the tests ar e reported as graphics showing the progress of growth in the cultures at various concentrations of the treated ballast water and concentration/response plots with a response curve fitted to the observations and indications of
the effect concentrations EC 10 and EC 50 which are derived from the response curve. The EC 10 and EC 50 are the concentrations (expressed as % trea ted ballast water) th at cause 10% and 50% reduction of the growth rate of the algae, respectively. This implies that a low EC 50 indicates a high toxicity. For those test s that the growth inhibiti on was too low to derive EC 10 and EC 50 by curve fitting, the NOEC was reported as the lowest test concentration causing a statistically significant reduction of the algal gr owth after 72 hours. An exampl e of the results is shown in Figures 9 and 10 below (Test 8, day 0).MEPC 58/2/1
ANNEX Page 18

I:\MEPC\58\2-1.doc 1 10 100 1000

0 20 40 60 80

Hours106cells/l 10

18

32

56

100

Control Concentration (%)

Figure 9: Growth curves of S. costatum at various concentrations of treated ballast water

0 20 40 60 80 100 120

1 10 100 1000

Concentration (%)Growth rate (% of control)

Figure 10: Concentration/response plot showing the effect of treat ed ballast water on the growth rate (0-72h) of S. costatum

The growth curves (Figure 9) show that the growth in the control (untreated ballast water) and at
low concentrations of the treated ballast wa ter (10% and 18%) was exponential throughout the three day incubation period as indicated by the straig ht curves when cell density is plotted against a logarithmic y-axis. At 32% con centration, the growth wa s slightly reduced in itially, but during the last two days the growth rate was as high as or even slightly higher than in the control as indicated by the slope of the growth curve. At 56% concentration, the growth was completely inhibited during the first day, but after that the algae seemed to recover and the growth rate was almost as high as in the control in the undiluted treated ballast water. The growth inhibition was complete throughout the exposure period and no r ecovery was observed. This growth pattern which was seen in most of the tests, indicates a gradual decrease of the toxic effect during the three-day test at intermediate concentrations of the treated ballast water. The final effect concentrations were calculated for the average growth rate during the entire exposure period (0-72 hours). In this case the EC 50 was 57% and the EC 10 was 39% (Figure 10). Because of the apparent recovery of the algae during the exposure, calculation of the EC-values during the initial phase of the test (0-24 or 0-48 hour s) would yield lower EC-values.MEPC 58/2/1
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I:\MEPC\58\2-1.doc With respect to 0 day samples the EC 50 estimates vary in the rang e of 16% to >100% with a
mean of 47%. Test water with 32 PSU had a mean EC 50 of 27%, while 22 PSU water had a mean of 68%. This difference probably reflects the influence of greater amount of organic matter in the 22 PSU test water, giving a more rapid degrad ation of the active C2E disinfectants in the low salinity water. It should be noted that the water samples were stor ed at 4-6 °C overnight before the toxicity tests were started.

In most of the test runs, the EC-values were high er at 5 days after treatment than at day zero, and
on several occasions EC 50 could not be derived. Therefore, the EC 10 or NOECs should be used for comparison. The EC 10 /NOEC values vary in the rang e of 26% to 100%, with a mean of 68.4% for all tests of day 5 samples. Fo r 32 PSU, water the mean was 68.8% while it
was 68.0% for 22 PSU water. The difference in obs erved effect level found for 0 day samples is no longer there for the 5 day samples. There were some instances were the residual toxicity for 5-day samples were at a level that allowed estimation of an EC 50 value. The 5-day test sample for test Nos. 8, 10, 11 and 13 had EC 50 of 66%, 53%, 93% and 39%, respectively. These values
indicate that sometimes there are small residual amounts of biol ogical active compounds in the
treated water even after 5 days.

The dose response curve is often quite steep as indicated by a low EC 50 /EC 10 ratio. This is indicative of presence of powerful biological re active compounds. In the most extreme case, the ratio is only 1.13 as on day 0 in test 13. The most extreme the other way is 2.7 on 2.day, test 5. The steep response curves can be related to the growth respons e pattern that was observed and exemplified by the growth curves in Figure 9 a bove. The apparent recovery of the algae at
intermediate concentrations results in small reduc tion of the average (0-72 hours) growth rate as compared to the control cultures even if a substa ntial initial growth inhi bition is observed. Above a critical concentration, however, the growth inhibition is comp lete and no recovery occurs. This response pattern may be caused by a partial destruction of the al gal cells caused by the initial
concentration of oxidants. When the concentrat ion of oxidants is high enough to destroy all the cells, no recovery is observed. When only a frac tion of the cells are de stroyed, the remaining cells are able to grow at a normal rate once the concentration of oxidants has decayed below a critical level. The decay of the oxi dant concentration is linked to the destruction of the algal cells.

The response of algal growth inhibition tests of organic substances with a non-polar narcotic mode of action is usually characterized by a more constant growth reduc tion (less recovery) and lower slopes of the concentration/response curves. This may indicate that the observed effects of the treated ballast water are mainly due to oxidants and not by-produc ts like halogenated organics. Even the most toxic halogenated organic by-product li ke bromoform has an NOEC for algae (the most sensit ive trophic group) of ≥ 2 mg/l (Erickson and Hawkins 1980). For bromoform, the lowest EC 50 found for algae ( Skeletonema costatum ) is 12.3 mg/l with respect to photosynthesis (Aquire, US EPA database). With an initial oxidant level of even 3 ppm, it is not expected that bromoform levels would reach such toxic levels.

Bromoform has been measur ed in 6 of the tests (see some of the results in Table 5-1) with a
maximum concentration in treated water after 5 days of 0.29 mg/l, and an average concentration of 0.185 mg/l. This value includes both measurem ents for test 5. As the bromoform NOEC is ≥ 2 mg/l and bromoform is the most toxic halogenate d organic by-product expected to occur, it is unlikely that any of the observed effects seen in the algal tests are caused by by-products.MEPC 58/2/1
ANNEX Page 20

I:\MEPC\58\2-1.doc Bromoform is a volatile compound; therefore, brom oform released to seawater will eventually end up in the atmosphere where it has a decay 1⁄2 tim e of 80 h (Barnes et al., 1981). It has been estimated that about 70% of the global bromof orm production is pro duced by marine algae (Manley and Barbero, 2001).

7.3 Invertebrate toxicity testing

Acute toxicity testing with Acartia tonsa with 5 day treated water did not give significant mortality. However, the chronic reproduction test with Nitocra spinipes showed a significant 20% reduction in fecundity in both test water qualities. Again, i ndicating that there are small amounts of remaining biological active components in the treated water after 5 days.

7.4 Fish toxicity testing

Both acute and chronic testing was performed with turbot ( Scopthalmus maximus ) with both water qualities (Table 3-1). There was no mortality due to test compound in any of the tests and no significant reduction in growth ra te observed in the chronic tests.

7.5 Summary and conclusion wi th regard to ecotoxicity

Although a general rapid reduction in toxicity was observed in the samples from day 5 compared to day 0 samples, several day 5 samples show a sm all remaining toxicity that is evident in the chronic toxicity studies with S. costatum and N. spinipes . This makes it necessary to perform an environmental risk assessment taking into cons ideration the observed effects in these tests.

8 ENVIRONMENTAL RISK ASSESSMEN T ñ BALLAST WATER DISCHARGE

8.1 PNEC (Predicted No Effect Concentration) evaluation based on toxicity testing of
treated ballast water

Treated ballast water has, after a 5- day holding period, been te sted in acute a nd chronic tests with species from three trophic levels. From th ese tests, it is clear th at algae are the most sensitive group. According to TGD (EU, 2003) an Assessment Factor (A F) of 100 is then applicable for assessment of PNEC seawater . Given that there are several (11) tests available for 5 day holding period, the average EC 10 of 62.2% is used as basis. With an AF =100 this gives a PNEC of 0.62 of treated ballast water. There is no sign ificant difference between the results from high salinity tests, equal to 62.6% and brackish water tests, equal to 61.2%. A common average is therefore applicable and the common PNEC seawater becomes:

PNEC seawater = Average EC 10 =62.2% /100=0.62%

There is a need to redefine the units at this st age, in order to perform risk characterization. As evident from the toxicity testing (presented in detail in the Confidential Dossier), high EC 10 values are related to low toxicity of test water. In order to assess the PEC/PNEC ratio the following calculation needs to be performed. PEC=Inverse EC 10 value of test water =100/EC 10

. The PNEC needs to be multiplied with 100 in order to have same unit.

PEC/PNEC=100/EC 10 /PNEC*100 (1)

Table 8-1 presents the dilution fact or of ballast water necessary in order to reduce the risk below the threshold of PEC/PNEC=1 assuming no oxidant decay.MEPC 58/2/1
ANNEX Page 21

I:\MEPC\58\2-1.doc Table 8-1. Predicted necessary di lution factor after variable days of holding time to bring
PEC/PNEC ratio below the risk threshold of PE C/PNEC=1. The calculation is based on the EC 10 values for treated ballast water using the slop evalues calculated based on ecotoxicity results.
The estimated PEC/PNEC ratio is ca lculated according to equation (1).

Holding time of treated ballast
water in tank (Days) PEC/PNEC =
Dilution factor

0 346

1 325

2 306

3 289

4 274

5 261

6 248

7 237

The remaining toxicity of the treated ballast wate r found in the ecotoxicity tests is caused by the low concentrations (<0.5 mg Cl/L (0.5 ñ 0.05 mg Cl/L)) of residual oxidants after one day holding time. Bromoform is the most toxic disi nfection by-product expected to occur in the
treated ballast water and has been measured w ith a maximum concentration in treated water after 5 days of 0.29 mg/l, and an average concen tration of 0.185 mg/l. As the bromoform NOEC
is ≥ 2 mg/l, it is unlikely that any of the observed effects seen in the algal tests are caused by by-products.

The above calculations assume no decay of the residual oxidants, which is a very conservative assumption. When the treated balla st water is discharged into coastal and harbour waters, the residual oxidants will be exposed to organic mo lecules and particles wh ich are easily oxidized. A decay rate similar to the rates observed in th e ballast tanks can be expe cted. The half-life of TRO just after injection of C2E disinfectants into the ballast line is less than 30 minutes. This slows down to approximately one day mainly due to degradati on of the organic matter in the
treated water.

The calculated dilution factors for treated ballast water after one holding day in ballast tanks are used in the following risk assessments (sections 8.2 and 8.3). This dilution factor includes an
assessment factor of 100 in accordance with the EU TGD.

Two risk models have been applied with di fferent traffic scenarios. The MAMPEC model (section 8.2) has been used in se veral earlier ap plications. In addition, th e applicant has used the DREAM model (section 8.3) with more detailed hydrodynamic cal culations where the worst case scenario found during a whole year modeling (February 14th) has been used as basis for the risk

assessment.

8.2 Environmental risk assessmen t applying the MAMPEC model

A simplified risk assessment of the remaining ecotoxicity was performed using the
MAMPEC model for a worst case commerci al harbour scenario. MAMPEC includes a commercial harbour scenario (Rot terdam case study) with specifics as shown in Table 8-2. The
flush rate indicates fraction of water exchanged each day.MEPC 58/2/1
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I:\MEPC\58\2-1.doc Table 8-2 The MAMPEC commercial harbour scenario

Harbour Length (m) Width (m) Depth (m) Volume (m 3 ) Flush rate

Commercial

estuarine
habour 10000 2000 20 400x10 6 0.65

MAMPEC informs that Rotterdam in 1996 had 25,078 port arrivals with an average tonnage of 15,000 dwt. This indicates an average number of port calls of 68 ships per day. Table 4.23 in
the emission scenario document for anti-fouling products (EU, 2004), tabulates size and number of ships at port for 1 day. This gives a total release of ba llast water of 92,100 m 3 /day. This is
believed to be a conservative estimate as number of ships used is much higher than average and not all the ships will discharge ballast water. Rather the opposite is the case as ships unloading cargo will take on ballast water to comp ensate for the cargo taken on board.

Table 8-3: Based on the number of ships a nd categories given in Table 4.23 of the emission scenario document (EU, 2004) for a port like Rotterdam, the fo llowing ballast water volume released per day can be estimated.

No. of ships Ship size (m) Dwt Ballast (m 3 ) Sum ballast (m 3 ) 57.0 100.0 6615 1600 91,200 25.0 150.0 14,215 6000 150,000 24.5 200.0 30,547 12,000 294,000 5.5 250.0 65,646 20,000 110,000 7.5 300.0 141,074 28,000 210,000 1.5 350.0 303,166 44,000 66,000 Sum 111,600 921,200

Applying the total release of ballast water from Ta ble 8-3, equal to 921,200 m 3 /day give a build up of ballast water as shown in Table 8-4. It is assumed that ballast wate r is evenly distributed throughout the harbour. The dilution converges at a value of 280. This value may be compared to the required dilution of 261 found for 5-day old wate r in Table 8-1. As the dilution in the harbour is greater than required to meet the PNEC, the PEC/PNEC in this instance is less than 1. Using shorter holding times for ballast water gives a highe r need of dilution and therefore an estimated PEC/PNEC that may be grater th an 1. A worst case example usi ng the 2-day dilution value from Table 8-4 gives a PEC/PNEC of 1.88. In both calcu lations, the TRO is assumed to be persistent with no decay as discussed in section 8.1.

Several studies related to the decay of TRO have been documented that this follows an exponential equation with less than 30 minutes ha lf-life of TRO immediately after discharge.

Table 8-4 Estimated dilution of ballast water

Dilution

Released ballast (m 3 ) 1 day 2 day 3 days 4 days 921,200 434 322 295 287MEPC 58/2/1
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I:\MEPC\58\2-1.doc Using a realistic worst case scenar io from MAMPEC and estimated dilution requirements to reach
PNEC from the land -based tests, it is fo und that estimated PEC/PN EC may vary between 1.88 and 0.9 using holding times of 2-5 days based on the traffic scenario as described above. One should
have in mind that these es timates are very c onservative as they assume no oxidant deca y, that all ships arriving at the port releas e ballast water (probably less than 50% do so), and the number of ships is 80% higher than the average number for Ro tterdam. Lastly, it is unlikely that all ships
will have ballast water that is treated with the OS BWMS technology. It is therefore highly unlikely that PEC/PNEC>1 will occur.

8.3 SINTEF- environmental risk assessment in two harbours

The DREAM model tool has also been utilized to calculate the potential environmental impact caused by discharge of ballast water treated with OS BWMS at two different locations on the Norwegian coast (Mongstad and Fredrikstad).

The model was chosen because it gives de tailed hydrodynamic results where worst case situations may be chosen from a modeled full year discharge scenario.

The two locations are selected due to variati ons in currents and hydrography. For the Mongstad case, the winter month of February is simula ted (weak currents and stratification). For the Fredrikstad case, the month of May is simulated (strong river flow and also strong stratification due to the presence of the river water masses).

Figure 11: Location of the two si tes considered in the present report, Mongstad and the Glomma archipelago (Fredrikstad).MEPC 58/2/1
ANNEX Page 24

I:\MEPC\58\2-1.doc The traffic used for the Mongstad port is the real traffic of crude and product tankers at this oil terminal as given by the opera tor StatoilHydro. With respect to ballast water discharge, Mongstad is one of the larg est recipients in Europe.

Table 8-5: The ship categories and corresponding discharges for the Mongstad case (oil terminal and refinery). Discharges are given as an averag e for one year. BW (tons) is the total amount of ballast water discharg ed over a whole year

.

Mongstad Size categories (dwt) Size (dwt) 12 000 50 000 100 000 150 000 250 000 350 000 SUM

No. tankers 600 200 80 70 40 10 1000 BW (tons) 2 880 000 4 000 000 3 200 000 4 200 000 4 000 000 1 400 000 19 680 000 Discharge rate (ton/h) 600 1800 3500 5000 5500 8000 Discharge depth 5 6 7 8 10 10

The traffic in the Fredrikstad port is low and th e location was chosen mainly due to the limited port area (water volume) and strong stratification of the water column due to large fresh water
effluent from the river Glomma. To increase traffi c and thereby ballast water discharges, the ship traffic from the LPG terminal KÂrst ̄ was assumed located at Fredrikstad.

Table 8-6: The ship categories and corres ponding discharges for the Fredrikstad case (traffic from the LPG terminal at KÂrst ̄). Disc harges are given as an average for one year. BW (tons) is the total amount of balla st water discharged over one year.

Fredrikstad Size categories (dwt) Size (dwt) 4 000 15 000 30 000 50 000 70 000 110 000 SUM

No. vessels 180 120 120 90 80 10 600 BW (tons) 288 000 720 000 1 440 000 1 800 000 2 240 000 440 000 6 928 000 Discharge rate (ton/h) 200 750 1500 2000 2500 4000 Discharge depth 3 5 5 6 6 7

This study was aimed at considering environmental risk when treated ballast water is discharged
to the sea. Based on the evaluation in secti on 8.1 three cases have been considered:

- Base case : PNEC at dilution 400. No oxidant decay included
- Case 2 : PNEC at dilution 400. Oxidant decay included
- Case 3 : PNEC at dilution 260. Oxidant decay included

Discharges from 6 different ship /tanker categories are programmed with discharges with regular time intervals for the various ship/tanker categor ies through one month for each of the locations
selected. The DREAM model has calculated the dilution of the various discharges and thus determined the volumes of water impacted (at any time through the month simulated) with water
masses diluted with a factor less than 400 or 26 0 (that is, PEC/PNEC > 1 for the ballast water when the dilution is less than 400 and 260, respec tively). Two of the cases also include some oxidant decay (a conservative 6 hrs half-tim e as to the 30 min half-time experienced the comprehensive assessments undertaken by NIVA).MEPC 58/2/1
ANNEX Page 25

I:\MEPC\58\2-1.doc The locations considered have ye arly discharge rates that are so mewhat different. Total discharge through one year is slightly below 20 mill. t ons/year for the Mongstad case, and slightly below 7 mill. tons/year for the Fredrikstad case. Therefore, impacted volumes of recipient water are expected to be larger for the Mongst ad case than for the Fredrikstad case.

Time plots are presented for calculated volumes of water impacted with dilutions less than required (including effects from oxidant decay) for the three cases considered (for both Mongstad and Fredrikstad) at any time through the simulati on period. The results are presented in Table 8-7
below.

Table 8-7: Summary of results from DREAM simulations of vol umes of water impacted with
PEC/PNEC > 1.

Location Case Dilution requirement Oxidant decay Maximum volume of water
x 10 5 m 3 (PEC/PNEC>1)
Base case 400 No 370
Case 2 400 Yes 70 Mongstad
Case 3 260 Yes 38
Base case 400 No 35
Case 2 400 Yes 20 Fredrikstad

Case 3 260 Yes 13

As expected, impacted volumes of water are largest for the Mongstad case, without oxidant decay. Impacted volumes of water are smallest for the Fredrikstad case, with oxidant decay
included.

Details from the calculations of Case 3, PNEC at dilution 260, with decay is presented in more detail in the following figures. Figure 12 shows th e concentration field downstream caused by the discharge from the various sources with the maxi mum volume of water impacted with a dilution of 260 of the ballast water (PNE C is at the concentration le vel of 3.846 ppm, 1000 ppm in the ballast water before discharge).MEPC 58/2/1
ANNEX Page 26

I:\MEPC\58\2-1.doc Figure 12, Case 3, Mongstad. Concentration field ge nerated from discharge of ballast water for
the case with a PNEC level of 260 dilution of the ballast water. With decay. Concentration level of 3.846 ppm for the tracer shown corresponds to th e PNEC level of the treated ballast water (concentration in the discharge is assumed to be 1000 ppm of th e tracer). Discharge during the month of February. Aerial view is shown to the le ft, vertical cross section is shown to the right.
The cross section selected is shown w ith an arrow on the figure to the left.MEPC 58/2/1
ANNEX Page 27

I:\MEPC\58\2-1.doc Figure 13 shows the similar risk field for the concentration field shown in Figure 12.

Figure 13, Case 3, Mongstad. Maximum risk fi eld found in the simulations. Risks are
encountered when the ratio PEC/PNEC > 1. Aerial view is shown to the left, vertical cross section is shown to the right. Th e cross section selected is show n with an arrow on the figure to
the left.

Figure 14 shows the time development of the water volume impacted by ballast water diluted less than 260, including effects from the decay. For such a case, the ratio PEC/PNEC > 1 and thus has a potential risk for damage on the biota in the re cipient. Due to the deca y of the toxic compounds in the ballast water, the water volume of the imp acted water is significantly reduced, compared to the Base case with no TRO decay.MEPC 58/2/1
ANNEX Page 28

I:\MEPC\58\2-1.doc Time development chart

0 5 10 15 20 25 30 35 40

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27

Time (days)g

Figure 14, Case 3, Mongstad. Time development of the water volume impacted by a dilution that
is less than 260 of the ballast water. Decay included. Calculati on for the month of February.
Units on the vertical scale is 10 5 m 3 of sea water.

Case 3 represents a conservative approach since no ecotoxicity was found after a dilution of 1:2 or more in the ecotoxicity tests. When diluting th e treated ballast water in the ecotoxicity tests, seawater with low content of organic matter was used. If normal harbour water or coastal water had been used, even lower dilution than 1:2 would have given no remaining ecotoxicity as result.

In addition, the assessment factor 100 was used as recommended by the EU TGD (2003). The maximum allowable discharge concentration of TRO in ballast water treated with OS BWMS is 0.5 mg Cl/L (ranging from 0.5 ñ 0.05 mg/Cl/L). Due to the assessment factor, this TRO has to be
diluted with a factor 1:400 down to a concentration far below any detectable level indicating that there are remaining ecot oxicity at concen tration down to approximat ely 0.001 mg Cl/L. This concentration is below expected concentrations of naturally occurring TRO in surface water exposed to sunlight.

Different oxidant treatment systems are used to prevent bio-fouling in coastal power stations. Chlorination using hypochlorite or electrolysis of seawater are standard technologies for such treatment. According to Taylor (2006), 50 ñ 85 m 3 /h of chlorinated coo ling water effluent is discharged to the recipient coastal waters from these power stations. A 60 m 3 /h discharge accumulate to nearly 2000 mill. m 3 yearly discharge of oxida nt treated cooling water. In comparison, the oil terminal Mongstad repres ents one of Europeís largest ballast water discharge localities with a total discha rge of ballast water of 20 mill. m 3

.

Taylorís paper reviews the current understandi ng of the degree of impa ct involved of these discharges. The paper describes a recent colla borative programme of work on chlorination by products within the wider contex t of a number of allied studies on power station cooling waterMEPC 58/2/1
ANNEX Page 29

I:\MEPC\58\2-1.doc entrainment and discharge effects. The results suggest a very limited impact of oxidant use and the associated chlorination by-products on receivi ng waters both in terms of plume toxicity or any more widespread ecotoxicological influence. Instead, it is the combination of applied temperature, pressure and the ot her stressors involved in entrai nment within the power station cooling water circuits themselves that cause a marked impact in the recipient.

8.4 Risk assessment ñ discharge of hypoxic ballast water

A study carried out by DNV (DNV, 2007) investigated the dilution of six typical scenarios of ballast water discharge in a harbour recipient. A total ba llast water volume of 50,000 m 3 is assumed discharged at a rate of 6,000 m 3 /h. A typical harbour dept h of 20 m is assumed.

The discharge velocity is assumed to be just le ss than 4 m/s. A discharge pipe diameter of 750 gives a velocity of 3.77 m/s. The discharge of wa ter is assumed to occur at 8 m depth. This may be assumed to be a ìworst case scenarioî compar ed to a surface discharge, in that a surface discharge may experience more turbulent mixing.

The initial mixing of the discharge in the recipien t is modelled using Visual Plumes. This is an industry-standard tool pr ovided by the US EPA (see www.epa.gov/ceampubl/swater/vplume/ ).

A range of 6 scenarios are defined, combining 2 cases of longshore curre nts with 3 cases of density difference between discharge and recipient, thereby investigating the effect of density and currents on the extent of the plume:

.1 no density differe nce, no current; .2 no density difference, transverse current; .3 brackish recipient, no current; .4 brackish recipient, transverse current; .5 brackish ballast, no current; and .6 brackish ballast, transverse current.

A near-zone of 300 m along the quay and 200 m from the ship side is defined. The total volume of this zone is 1,200,000 m 3 . Therefore, excluding the effect of initial momentum and longshore currents, the discharge will be diluted >20 times within this zone.

The boundary defining the near-zone has a flux area of 14,000 m 2 . The flux of discharged ballast water through this boundary, again excluding the effect of initial momentum and longshore currents, is 0.42 m/h. Therefore, excluding th e effect of initial momentum and longshore currents, it can be said that the discharge will be diluted >20 times within the 300 x 200 m near-zone to the discharge point, and that the flux of ballast wate r out of this zone is low.

The initial mixing of ballast water gives a diluti on of more than 20 x within 50 m of discharge. This is supported by general considerations of volumes and discharge rates, which find that excluding the mixing effects of th e initial momentum, and any l ongshore currents, a 20 x dilution
is achieved in a 300 x 200 m near zone. The harbour current pattern will aff ect the influence zone to a great extent. Tidal currents and river flows can in many cases be expected to stretch the influence zone downstream and upstream.MEPC 58/2/1
ANNEX Page 30

I:\MEPC\58\2-1.doc Oxygen levels in coastal su rface water varies normally between 6 and 14 mg O 2 /l depending on organic load and algae blooms. Degradation of organic matte r will consume oxygen causing lower levels and the photosyntesis of algae cause higher oxygen levels.

Ballast water treated with the OS BWMS is supe rsaturated with nitrogen and the oxygen level is between 2 and 3 mg O 2 /L. When ballast water low in oxygen is discharged to the sea, the oxygen level in the plume spreading from the point of discharge will increase due to mixing with oxygen-rich (6 and 14 mg O 2 /L) seawater. Using the dilution factor of 1:20 within 50 m of discharge, found in the calculations above, the oxygen level in the plume will reach the same level as seawater at this distance from the discharge point. Hence, discharge of ballast water will have a local effect on seawater quality in terms of oxygen, limited to a 50 metres distance from the ship. With ballast water containing 2 mg O 2 /l, the oxygen content in the plume 50 m away from the discharge is calculated to 5.8 mg O 2 /L.

It may be noted that conventional (untreated) ballast water discha rged from ships following some time of storage is characterized by typically having a redu ced level of oxygen naturally consumed by organisms present in the water. The oxygen levels in ballast tanks after treatment
with the OS BWMS is held constant around 2-3 mg O 2 /L while the oxygen le vels in conventional ballast tanks slowly decrease and reach approximately the same level in the lower section of the tank after some days or week s depending on the water quality.

8.5 Conclusion ñ environmental risk assessment

Two different models have been applied to assess cases in three different ports. The scenarios have applied a conservative approach with regard s to decay as well as to discharge volumes.

Based on the available ecotoxicity data an envi ronmental risk assessment has been performed applying different models; MAMPEC and DREAM.

The MAMPEC model is a simple box-model calcu lating concentrations in Rotterdam harbour with a worst case emission scenario assuming that all ships entering the port, discharge all ballast
water on board. It is found that estimated PEC/PNEC may vary between 1.88 and 0.9 using holding times of 2-5 days. These estimates are conservative as they as sume no oxidant decay. By including a decay rate following a exponential function as found in seve ral earlier studies as well as in this study, the PEC/PN EC level is below 1 for all hol ding times of ballast water.

The DREAM model includes more detailed hydr odynamic calculations, which make it possible to find a worst case discharge scenario for a whol e year. For the Mongstad oil terminal, this was found to be February 14 with lo w stratification of the water colu mn and weak currents leading to a low dilution of the discharges. With an assess ment factor 100 and assuming linear decay of the remaining TRO, the PEC/PNEC was found to be slightly above 1 in a volume of 4 mill. m 3

. Due to the assessment factor, the TRO has to be diluted with a factor 1:400 down to a concentration far below any detectable level indi cating that there are re maining ecotoxicity at
concentrations down to a pproximately 0.001 mg Cl/L.

An assessment of the implications of discharg ing ballast water low in oxygen has also been undertaken. It may be noted that also untreated ba llast water from ships will have a reduced level of dissolved oxygen dependent upon st orage time and organic content.MEPC 58/2/1
ANNEX Page 31

I:\MEPC\58\2-1.doc Using the dilution factor of 1:20 within 50 m of discharge, found in the calculations in chapter 8.4, the oxygen level in the pl ume will reach the same level as seawater at this distance from the discharge point. Hence, discharge of ba llast water will have a local effect on seawater quality in terms of oxygen, limited to a 50 metres distance from the ship. With ballast water containing 2 mg O 2 /l, the oxygen content in the plume 50 m away from the discharge is calculated to 5.8 mg O 2 /L.

9 HUMAN EXPOSURE ASSESSMENT

9.1 Introduction

The human health risk assessment of the O ceanSaverÆ Ballast Water Management System covers risks to human health due to potentia l exposure to chemicals during normal operation, accident situations, as well as incidents following equipment maintenance as well as malfunctioning and failure.

The assessment focuses on two groups: the crew on board the ship, and the general public (users of coastal areas, beach coastlin es and offshore installations and harbours (GESAMP-BWWG 3/9).

The assessment is based on the wo rk processes/unit operations i nvolved with the OS BWMS in which exposure to humans occur. A unit operation is a basic step in the process encompassing individual system components that are likely to lead to huma n exposure to Active Substances, Relevant Substances and by-pr oducts (GESAMP-BWWG 4/9).

In this risk assessment, the applicant addresse s nitrogen exposure, exposure to chemicals and substances used in the treatment process, and exposure to the halogenate d by-products in treated ballast water, generated by the electrochemical process (C2E). The applicant assesses the intensity and duration of exposur e to halogenated by-products, fo llowed by a characterization of the risk for human health applying WHO guide line values for drinking water quality (WHO, 2003). The WHO guidelines are founded on comprehensive studies of risks for human health when exposed to disinfectant by-products.

9.2 Risk characterization during normal operation

9.2.1 Risk characterization for the operator during ballasting

There are two possible scenarios for operation of the OceanSaverÆ Ballast Water Management System as follows:

ñ the system is operated by deck officers. The system will in this case be remotely controlled, preferably from a deck office. The possibility of exposure to harmful substances to the person in question is equal to zero; and

ñ the system is operated by the engineers. The system is controlled from the engine control room (ECR). As long as the engineer is located in these premises, there is

no exposure.

Common for both scenarios is that engine room personnel will be performing daily routines in the area where the system is located. Under normal operation, the BWT system is to be
considered as a closed circuit. There is no e xposure to anolyte (AWAC) , catholyte (AWAL) or
N 2 during normal operation (exposure to these substa nces can only occur as a result of breakage in the piping).MEPC 58/2/1
ANNEX Page 32

I:\MEPC\58\2-1.doc Due to possible leakage of N 2 , sensors detecting O 2 levels are installed in all rooms affected by piping connecting the N 2 generator to the ballast water pipeline as well as in the area where the
N 2 generator is located. There is also an internal O 2 sensor inside the N 2 generator for internal gas leakage. If the sensors detect a leakage of N 2 , the system automation will record an alarm and the system will enter shutdown mode.

Any individual O 2 sensors will activate system shutdown should the O 2 level fall below 19%. It may be noted that the extent of this safeguard exceeds that of the requirements of class for such systems.

There is no health risk for th e operator during normal operation.

9.2 Risk characterization for the crew and general public during ballasting

During ballasting, the air in the empty ballast tank s will gradually be vented out of the tanks as the air is replaced by the rising water and residual N 2 . The air can contain halogenated compounds found in the ballast water that could impl y a health risk if i nhaled. The tank air is released through vent-heads usuall y located on the deck edge, along the deck hatch frame or less commonly, on the side of the ship (for instance on car ships and RO/RO ships).

Crew on deck can be exposed to the vented ta nk air. The intensity a nd duration of exposure depends on various factors, for instance, type of ship. On LNG-tankers, no-one is allowed on deck during ballasting, resulting in no exposure. On other ships, there could be crew working on deck while ballasting is on-going. The maximum dur ation of the exposure e quals the duration of the ballasting. Duration of ballasting is maximu m 10-12 hours for large sh ips with big ballast tanks (ìworst case scenarioî).

The intensity of exposure varies with, for instan ce, wind conditions and how close a person is to the vent-head. It is not likely that anyone will be located right next to the vent-head and inhale the released air directly for the duration of the ballasting. More likely, persons on deck will
inhale air from the vent-head that is mixed and diluted with ambi ent air, reducing the exposure to any halogenated by-products. The worst-case w eather condition is considered to be no wind, reducing the effects of mixing and, hence, dilu tion. In a best-case scen ario, wind directs the discharge from the vent-heads away from the shi p, resulting in minimal exposure for persons on
deck.

The compounds detected in treated ballast water are equal to the compounds formed as by-products during chlorination of drinking water. WHO gui delines for drinking water 1 (WHO, 2003) include risk assessments of inha lation of these compounds. For this reason, WHO Guidelines have been applied to assess the h ealth risks for crew inhaling tank air released during ballasting. The assessment is done by comparing the guidelines with measured
concentrations in treated ballast water. The compounds in question are bromodichloromethane, bromoform, chlorodibromomethane, dichlorome thane and vinyl chloride. Table 9-1 gives
WHO Guidelines and concentrations in tr eated ballast water (maximum and mean concentrations) for each of the compounds in question.

1 WHO has developed a comprehensive backgrou nd documentation about the chemical hazards in drinking water for the ìWHO Guidelines on Drinking-water qualityî. The documentation can be found

at: www.who.int/water_sanitation_health/dwq/chemicals/en

.MEPC 58/2/1
ANNEX Page 33

I:\MEPC\58\2-1.doc Table 9-1: WHO guideline values for drinking-w ater quality and the concentrations in the
treated ballast water

BromodichloroMethane Bromoform Chlorodibromomethane Methylene
bromide
Dibromomethane Dichloromethane Vinyl
Chloride

CAS NR 75-27-4 75-25-2 124-48-1 74-95-3 75-09-2 75-01-4
WHO Guideline Value (mg/L) 0.06 0.1 0.1 0.02 0.0003

Highest measured
concentration in
Ballast water (mg/L)* 0.0009 0.3 0.02 0.0004 0.9 0.0003

Mean value of
measured
concentration in
ballast water (mg/L) 0.00004 0.2 0.01 0.0002 0.1 0.0002

* data from NIVA-report found in full application

Three compounds in ballast water are found in c oncentrations lower than the WHO guideline; bromodichloromethane, chlorodibromomethane, and vinyl chloride.

Two compounds are found in concen trations higher than the WH O guideline value for drinking water quality; bromoform and dichloromethane. The implications of this is investigated further by calculating the concentration of bromoform a nd dichloromethane in the air just above the water surface using Henrys law, and comparing these calculated values with the Norwegian
administrative norm 2 for 8 hours work. The concentration of bromoform in the air was calculated to 0.004 mg/m 3 and the administrative norm is 5 mg/m 3 . The concentration of dichloromethane was calculated to 0.056 mg/m 3 and the administrative norm is 50 mg/m 3 . Thus, the calculated
concentration values in the vented air for these two com pounds are much lower than the Norwegian administrative norms.

The compound dibromomethane id entified in the ballast water is not mentioned in the WHO guideline. The measured concentration in the ballast water was low with a maximum concentration of 0.0004 mg/L (Table 9-1). The c oncentrations of dibr omomethane are on the
same level as the concentrations of vinyl chloride, and it is not more toxic (E PA, 2008 ). On this basis, dibromomethane in treated ballast water is considered to imply the same health risk as vinyl chloride.

The low concentrations of compounds in ballast water compared to WHO guidelines for drinking water and Norwegian administrative norms indicate th at the health risk related to inhalation of tank air for persons on deck is very low . It is worth noting that exposure to tank air is less frequent and of lower intensity than exposure to drinking water vapours, which should imply that the risk characterization is conservative. There is no need for risk mitigation measures.

If the wind directs the released tank air to the nearby port/coast, third part y in the port/coast can be exposed to the tank air. The health risks involved for third party is equally very low.

Release of N 2 through the vent heads is of no hea lth risk to persons on deck, as N 2 , being lighter than air, will rise up vertically in the open rapidly, and disappear.

2 The Norwegi a n a d m i nistrative nor m i s bas e d o n E E A

- r e q u i re m en t s

.MEPC 58/2/1
ANNEX Page 34

I:\MEPC\58\2-1.doc 9.2.3 Risk characterization for the operator a nd crew during discharge of ballast water

There is no exposure to the operato r or crew during discharge of ba llast water as the ballast water is discharged under sea level.

9.2.4 Risk characterization for the general public during discharge of ballast water

Seafood such as shellfish and fish can be harves ted from areas where tr eated ballast water is discharged. The halogenated compounds found in treated ballast water are found to be not bio-accumulating (MEPC 57/2/6). Hence, thes e compounds will not be found in seafood. As a result, there is no health risk c onnected to consumption of seafood taken from areas where ballast water is discharged.

People can be swimming in ports or nearby beach es while ships are discharging treated ballast water, possibly getting exposed to treated ballas t water via skin contact, inhalation (of vapours) and swallowing of (small amounts of) seawater. WHO guidelines for drinking water quality are
used to assess the health risks in connec tion with swimming. The guidelines cover risk assessments of halogenated compounds for all three exposure paths. Two compounds in treated
ballast water have been found in concentrations higher than th e WHO guideline; bromoform and dichloromethane, the latter found in the highest concentration comp ared to the guideline value.
The mean concentration of dichloromethane is 5 x guideline value, and the maximum concentration is 45 x the guideline va lue. When discharged to sea, the plume of ballast water will be diluted in seawater, reducing th e concentrations of dichlorometh ane in the plume. The dilution is previously modelled to 1:20 within 50 metr es from the discharge (section 8.4). For anyone swimming in the sea at a distance of 50 m from the discharge point, the water will be of WHO drinking water standard in terms of dichlorometh ane. Concentrations of the other halogenated compounds will be much lower than the guideline valu e. Only if a person gets very close to the discharge (a few metres away) is there a risk of exposure to concentrations above WHO guidelines for drinking water. Hence, the health ri sk in connection with sw imming in the vicinity of ships discharging ballast wa ter is assessed as very low

.

9.3 Risk characterization during maintenance

9.3.1 Maintenance of the C2E unit

As part of maintaining the cells in the C2E uni t, the cells are to be flushed with AWACLEAN, a 7% solution of vinegar. Flushing takes place af ter ballasting or after approximately 10-12 hours of use. The C2E flushing system is a relatively simple device. The system consists of a 100-litre tank in addition to valves and a small pump. The fl ushing system is integrated in the OS BWMS and controlled by the OS automation w ith its own start/stop sequences.

Filling up the storage ta nk for the vinegar is manual labour. Th e operator can inhale fumes from the vinegar during filling, and po ssibly spill vinegar on hands and clothes. The intensity of the exposure is considered low and the duration is shor t, as the filling proced ure is completed within minutes. Emptying the tank is a closed circuit pr ocess. It consists of opening a valve under the tank and draining it to the bilge, hence, there is no exposure to vinegar that is emptied from the
tank.MEPC 58/2/1
ANNEX Page 35

I:\MEPC\58\2-1.doc Vinegar is a dilute solution of acidic acid. Diluti ons with an acidic acid concentration below 10%
are not classified as a hazardous chemical according to European Inventory of existing
Commercial Chemical Substances (EINECS). A 7% solution of vi negar is considered as a food
article and there is no health risk in connecti on with neither normal handling nor spillage.

9.3.2 Maintenance of the ballast water tanks

Before entering a ballast tank, the tank must be free of both hydrocarbon and inert gasses to secure a safe working environment. This invol ves blowing fresh air into the tank to force accumulated gasses out. There are strict requiremen ts and thus routines associated with securing safe breathable atmospheres before personnel are allowed to enter any tanks on board ships. This is according to class regulati on. Specially trained personnel shal l monitor the tankís atmosphere during the process, often using hand-held gas indicators which measur e the percentage of hydrocarbons present as well as e.g. oxygen. There can be N 2 in the tank resulting from the ballast water treatment. However, existing procedures for work in a tank means that any N 2 in the tank due to ballast water treatment will not pose a ny additional health risk to personnel entering the tank. Hence, there is no need for additional risk mitigation measures.

When a ballast water tank is full and N 2 is accumulated in the head space, oxygen leve ls will be low. There will be no human exposure to the ga ses in the headspace of the ballast tanks, as opening and inspection of the tank is strictly prohib ited when the vessel is operating in this mode. This is also according to class regulation. Note also that the OS BWMS employs active tank ventilation management as conventional vent-hea ds are replaced by pressure/vacuum vent-heads. Thus, under normal operations, ther e will be no releases from the vent-heads except during ballasting.

9.4 Risk characterization in accident situations

There is no exposure to the C2 E disinfectants (anolyte (AWAC) , catholyte (AWAL)) or to N 2 during normal operation. Exposure to these substances may occur on ly in the case of breakage in the piping. This type of fault will quickly be detected by the automation system as it includes internal leakage detection (insid e the C2E cabinet) and pressure lo ss monitoring (piping) that monitors the process. In the cas e of detected leakage, alarms are recorded and an immediate shutdown procedure of the C2E is activated.

If the breakage is located outside the C2E cabinet, the amount of AWAC and AWAL fluid spilled is limited to the amount within the pipes, from the point of leakage to the cabinet and
confined to a few litres. Personnel can remove the liquid by conventional means, using water and/ or an absorbent. The person will be exposed to whatever volume that is spilled. The C2E
solutions are classified as non- dangerous (88/279/EWG) but may cause irritation to the eyes,
sensitive skin and thro at. Conventional personal protective equipment (PPE) is considered adequate in order to protect against accidental exposure (i.e. gloves, and goggles). In case of ventilation breakdown or leakage, there is a risk of vapour or fumes to be released. These fumes may cause dizziness and nausea and inhalation shoul d be avoided. Respiratory protection should
be available. Note that ventilat ion performance is actively monitore d. Any failure will institute an alarm and consequently the system shutdown. The ri sk to human health is considered to be low

.MEPC 58/2/1
ANNEX Page 36

I:\MEPC\58\2-1.doc The C2E solution does not react with other material s and is stable and may be stored in sealed plastic containers.

If the breakage is inside the C2E cabinet, this is a sealed compartment w ith a built-in detection system and the risk of expos ure is considerably limited.

There are strict safety procedures in place to mi nimize the health risk for crew and other persons on the ship in connection with N 2 leakage from the N 2 generator or piping. N 2 is a non-toxic but asphyxiating gas. Due to possible leakage, sensors detecting O 2 levels are installed in all rooms affected by piping connecting the N 2 generator to the ballast water pipeline as well as in the area
where the N 2 generator is located. If the sensors detect a leakage of N 2 , the system will enter the
shutdown mode. An alarm will be activated if the oxygen level is reduced to 19%, and access to
the rooms will be denied. No-one will be able to enter the rooms until they are thoroughly ventilated and controlled, as the rooms will be closed, secured and have warning signs posted until they are safe to enter.

N 2 can migrate from the source to adjacent spaces. The safety procedures will ensure that also adjacent spaces and areas under potential nitrog en migration are close d, secured and warning signs posted. Each of the adjacent spaces wi ll be ventilated to secure that any N 2 that has migrated from the leakage point is vented out . When the safety procedures are followed, the health risks related to leakage of N 2 from the N 2 generator or piping is assessed as low

.

10 CORROSION

10.1 Introduction

To complement the development work of the OS BWMS in compliance with the intentions of the IMO Ballast Water Management Convention and the recommendations and guidance provided in the accompanying Guidelines (G8) and Procedure (G9), a corrosion and coating impact test programme has been devised by DNV, Safinah Lt d. in cooperation with Oc eanSaver/ Metafil. This program has been carried out in order to consider any effects on ballast tank coatings and further to evaluate the hypothese s that OS BWMS treatment would fulfil the criteria of not being detrimental to ballast tank coatings and also that the hypoxic or oxygen de ficient seawater would be beneficial in reducing the ra tes of corrosion. The test program ha s included desk-t op/ literature assessments as well as laboratory-ba sed and ship-based assessments.

A total of 12 ballast tank coatings representing conventional products, present standard coatings as well as state of the art coatings have been included. All tests are un dertaken by independent third parties in compliance with recognized test methods. Test reports have previously been submitted as enclosures to the Basic Approval. Two additional reports are included in the Confidential Dossier (Summary results of testing Seawater Ballast Tank Coatings under ìOceanSaverî Conditions (Safinah Ltd.) and Effect of Electroche mical Activation by the C2E component in the OS BWMS to cause Corrosion/Coating impacts in Ballast Tanks (Safinah Ltd.).MEPC 58/2/1
ANNEX Page 37

I:\MEPC\58\2-1.doc 10.2 Testing

The test program has included laboratory-based testing at the DNV Corrosion Laboratory in Bergen, Norway. Two ballast water tank simulato rs were applied with an unmodified tank acting as control with ìstandard 2 conditionsî. Two simulated test programmes were carried out: (1) coating study; and (2) corrosion study.

In addition and in parallel, tw o shipboard test programmes have been performed focussing on corrosion and coating impacts, respectively. Thes e programmes were undertaken over a period of more than 15 months on board the vessels; MV Hˆegh Trooper/MV Federal Welland

.

All testing has been undertaken applying filtration, cavitation (C3T) and nitrogen supersaturation only. The disincentive component of the OS BWMS (C2E) was excluded from testing. The effects of electrochemical activation repres ented by the C2E componen t in the OS BWMS to cause corrosion/coating impacts has been addres sed in the separate study as enclosed.

10.3 Results

The tests confirm that a decrease of oxygen content in water and in the humid atmosphere in the tanks causes a decrease of the gene ral corrosion rate of steel. A similar conclusion is drawn with regards to impacts on coated surfaces as referen ces are drawn to: (1) the formation of rust; (2) blistering; and (3) adhesion. In the tests re port, none observed rust ing, none blistering and adhesion strength similar to unexposed laborat ory retained reference control panels.

Following an in-depth analysis of the results from tests undertaken, it is concluded that the OS BWMS as tested has no recognizable detr imental effect upon the coatings or upon their corrosion protection properties. Furt her, it is reported that; ì...t he results show a higher anode consumption and current demand fo r the bottom panel in the untreat ed seawater compared to the nitrogen treated seawater, i.e. corrosion is suppressed under OceanSaver treatment conditions.î

10.4 The addition of the C2E disinfectant

Potential effect of electrochemical activation by the C2E treatment component in the OS BWMS to cause corrosion/coating impacts in ballast tank s when integrated with the remaining treatment stages has been studied. The work concludes th at free residual oxidant level in the treated seawater is present over a period of time approximated to 24 hrs. In itial values lies in the range of 2 ppm. Following resting in ta nks, these residual oxidants are consumed rapidly as illustrated in Figures 3 to 5. After 5 hours, the free re sidual oxidant level (FRO) is typically below 0.25 ppm. After a 24-hour period, levels are typically between 0.05 and 0.25 ppm.

Based on the identified rapid consume of the fr ee residual oxidants and the initial low starting level and on general available litera ture and experience, it is concl uded that it is unlikely that the introduction of the C2E component will have any effect on the coatings applied for corrosive protection of ballast water tanks. Similarly, it is unlikely that th e additional treatment component
will affect corrosion of steel.

It is further concluded that the overall positiv e effects of reduced corrosion is likely to be maintained with such low levels of active oxyg en species present over the short timeline.MEPC 58/2/1
ANNEX Page 38

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