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Land-Based Evaluations of the 

Siemens Water Technologies SiCURETM

Ballast Water Management System

Maritime(Environmental(Resource(Center

September 2010

c/o Chesapeake Biological Laboratory

University of Maryland Center for Environmental Science

PO Box 38, Solomons, Maryland 20688, USA

Ref. No. [UMCES]CBL 10-038
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Notice

The objective of this Maritime Environmental Resource Center (MERC) evaluation was 

to provide shipping lines, classification societies, regulators, and flag states with an independent 

and credible assessment of treatment performance under realistic conditions. Therefore, the 

ballast water treatment system was tested in accordance with the International Maritime 

Organization (IMO) International Convention for the Control and Management of Ships’ Ballast 

Water and Sediment (2004), Resolution MEPC.174(58) Guidelines for Approval of Ballast 

Water Management Systems (G8) and Resolution MEPC.169(57) Procedure for Approval of 

Ballast Water Management Systems That Make Use of Active Substances (G9). The evaluation 

was conducted under specific, predetermined, agreed-upon protocols, criteria, and quality 

assurance procedures to assess the treatment system's performance.

MERC does not label or list technologies as acceptable or unacceptable but will present 

the results in an objective way that can be used to determine regulatory compliance by 

appropriate administrations, agencies or certification societies. Subsequent data on the 

technology's performance characteristics is presented to allow for comparison with the IMO

Convention discharge standards, Regulation D-2, Ballast Water Performance Standard. 

MERC and the MERC Advisory Board do not provide certification for technologies, or 

certify that a technology will always operate as demonstrated. Additionally, no expressed or 

implied guarantee is provided as to the performance of the technology, or that a technology will 

always operate at the levels verified. MERC does guarantee the levels verified during the 

evaluation under the conditions, circumstances, and operations encountered as fully independent 

and credible. 

This report has been reviewed by members of the MERC Advisory Board and provided 

to Siemens and MERC funding agencies prior to public release. Mention of trade names or 

commercial products does not constitute endorsement or recommendation by MERC.

Questions and comments should be directed to Dr. Mario Tamburri, tamburri@umces.edu.
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Table of Contents

Page No.

1.0. MERC Background and Objectives...............................................................................1

2.0. Description of the Siemens Ballast Water Management System...................................1

3.0. Summary of IMO Standards..........................................................................................2

4.0. Summary of Test Protocols............................................................................................2

5.0. Summary of Results.......................................................................................................4

6.0 Results............................................................................................................................6

6.1. Trial 1 (SIE-03)..................................................................................................6

6.2. Trial 2 (SIE-05)..................................................................................................9

6.3 Trial 3 (SIE-06)................................................................................................11

6.4. Trial 4 (SIE-07)................................................................................................14

6.5. Trial 5 (SIE-08)................................................................................................17

6.6. Twenty-four Hour Dechlorination Trial ..........................................................19

7. Acknowledgements......................................................................................................23

Appendix A. Vendor Interpretation .........................................................................................24
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1.0 MERC Background and Objectives

The Maritime Environmental Resource Center (MERC) is a State of Maryland initiative 

that provides test facilities, information, and decision tools to address key environmental issues 

facing the international maritime industry. The Center’s primary focus is to evaluate the 

mechanical and biological efficacy, associated costs, and logistical aspects of ballast water 

treatment systems and the economic impacts of ballast water regulations and management 

approaches. A full description of MERC’s structure, products, and services can be found at 

www.maritime-enviro.org.

To address the need for effective, safe, and reliable ballast water treatment systems to 

prevent the introduction of non-native species, MERC has developed as a partnership between 

the Maryland Port Administration (MPA), Chesapeake Biological Laboratory/ University of 

Maryland Center for Environmental Science (CBL/UMCES), U.S. Maritime Administration 

(MARAD), Smithsonian Environmental Research Center (SERC), and University of Maryland 

(UMD) to provide independent performance testing and to help facilitate the transition of new 

treatment technologies to shipboard implementation and operations. 

This report describes the MERC evaluation of the Siemens SiCURETM Ballast Water 

Management System through objective and quality assured land-based testing (dockside at a

flow rate of 200m3/hr). The goal of this evaluation was to provide shipping lines, regulators, 

classification societies, and flag states with an independent and credible assessment of treatment 

performance under realistic conditions. Therefore, the data and information on performance 

characteristics covers legitimate information to meet the evaluation's objective, and performance 

is presented in a way to allow for comparison against the International Maritime Organization 

(IMO) International Convention for the Control and Management of Ships' Ballast Water and 

Sediments (2004), Regulation D-2 Ballast Water Performance Standard.

2.0 Description of the Siemens Ballast Water Management System

The Siemens Water Technologies SiCURETM Ballast Water Management System 

(BWMS) utilizes a combination of treatment methods including physical separation and a 

proprietary, on-demand treatment with biocides produced in-situ from seawater without the 

addition of chemicals. This proprietary technology is based on the maritime industry-proven 

Chloropac® biofouling control technology that was first developed in the early 1970s and 

installed on over 2,500 vessels.

The SiCURETM system employs electrolysis of seawater to produce a dilute solution of 

sodium hypochlorite as an Active Substance that is injected into the ballast piping. The 

proprietary controls regulate the system's parameters to provide only as much Active Substance 

as required to achieve the necessary level of disinfection. This approach is aimed at eliminating 

over-chlorination, associated risks of corrosion, and generation of disinfection by-products.

The specific SiCURETM unit tested as part of this MERC land-based evaluation was a 

prototype designed to land-based evaluation conditions with shipboard implementation 

considerations. For this land based test, the water is first filtered through a 40 micron 

BallastSafeTM BSFc Automatic Electric Filter, Model BSFc-H-1.6 prior to treatment. The 

sintered stainless steel screen technology enables it to remove zooplankton. BallastSafe’s filter 

features continuous cleaning of large volumes of dirt during ballasting without interruption, and 

a reversible screw system for cleaning of the entire screen surface. This system requires the 
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discharge/backflush of accumulated solid residue (or retentate).

To account for brackish water conditions, the addition of a brine (sodium chloride) 

injection system was included for proper operation during periods of relatively low salinity. The 

sodium hypochlorite solution was produced from a small side stream of ballast water from the 

main ballast piping. An advanced electrolyzer treated the side stream to create the required 

Active Substance concentration on-demand. The sodium hypochlorite/Active Substance solution 

was then injected both before and after the filtration unit. The pre filltration injection accounted 

for 10% or less of the total treatment dose for the purpose of filter biofouling prevention. An 

injection quill specifically designed for this application was implemented for the primary dose 

after the filter unit. The SiCURETM system doses at a maximum of 6 mg/l total chlorine. Upon 

discharge of treated water, total chlorine levels are monitored and if the levels are greater than 

the discharge limit of 0.1 ppm, an automated system injects sodium sulfite as neutralizer.

Because the treatment system was a prototype, it was operated at all times by members of 

the Siemens staff. All evaluation test equipment and instrumentation was operated by MERC 

personnel.

3.0 Summary of IMO Standards

This evaluation was designed to determine if the SiCURETM treatment system could meet 

IMO D2 standards in accordance with both the IMO Guidelines for Approval of Ballast Water 

Management Systems (G8) and the Procedure for Approval of Ballast Water Management 

Systems that make use of Active Substances (G9). The IMO Convention performance standard 

states that ships must discharge:

1) Less than 10 viable organisms per m3, greater than or equal to 50 μm in minimum 

dimension;

2) Less than 10 viable organisms per ml, less than 50 μm in minimum dimension and greater 

than or equal to 10 μm in minimum dimension and

3) Less than the following concentrations of indicator microbes, as a human health standard:

1. Toxigenic Vibrio cholerae (serogroups O1 and O139), less than 1 colony forming unit 

(cfu) per 100 ml 

2. Escherichia coli, less than 250 cfu per 100 ml;

3. Intestinal Enterococci, less than 100 cfu per 100 ml.

4.0 Summary of Test Protocols

The following is a brief summary of the testing approach and methods. For complete 

details on protocols, data management, and quality control / quality assurance procedures for this 

MERC evaluation, please refer to the Test Plan for the Performance Evaluation of the Siemens 

Ballast Water Management System (August 2009), available for download at www.maritimeenviro.org.

The protocols described below are based upon the IMO G8/G9 guidelines and the U.S. 

Coast Guard supported ETV protocols under development. Any deviation from IMO G8/G9

guidelines or draft ETV protocols were explained and justified in the Test Plan. 

MERC evaluated the biological efficacy of the SiCURETM ballast water treatment system 

onboard the U.S. Maritime Administration (MARAD) Ro-Ro vessel MV Cape Washington while 

docked in the Port of Baltimore. The ballast system on MV Cape Washington was modified to 
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allow for water at a flow rate of 400m3/hr to be split equally at flow rates of 200 m3/hr. Just 

before this split, challenge condition concentrations of total suspended solids (TSS) and 

particulate carbon (POC) were augmented by injecting a concentrated slurry of Arizona test dust 

and humic acid (developed and validated by the Naval Research Laboratory, Key West, Florida). 

The water was then delivered simultaneously to either a “control” (untreated) ballast tank or a 

“treated” (passing first through the SiCURETM system) ballast tank. These two tanks were used 

for the required holding time of five days and were essentially identical in size and structure. 

Each tank was filled to approximately 250 m3 for each test trial.

Physical Parameters - Temperature, salinity, dissolved oxygen, chlorophyll fluorescence, 

turbidity and pH were measured every 15 minutes during the test trials by two identical multiparameter probes placed, one each, into the control and test tanks. Initial inline samples of ballast 

water during the filling of the control and test tanks were collected, filtered, and analyzed (using 

USEPA methods) for the water quality parameters of particulate organic carbon (POC),

dissolved organic carbon (DOC) and total suspended solids (TSS) by the CBL/UMCES Nutrient 

Analytical Services Laboratory (NASL).

Sampling - A total of 10 identical 1.1 m3

 conical bottom mesocosms were also used for 

controlled sampling during each trial. Using the mesocosms, five sequential samples were taken 

during: (A) initial filling of tanks, just prior to the split of control and treated water (T0 Control), 

(B) initial filling of test tank, just downstream of the SiCURETM system during filling of test tank 

(T0 Treated), (C) during discharge of control water after a five-day holding time (TF Control), 

and (D) during discharge of treated water after a five-day holding time (TF Treated). 

Live Organisms > 50 μm - Immediately after filling, 1.0 m3

 of water in each mesocosm 

was filtered through a 35 μm plankton net to concentrate the zooplankton for qualitative and 

quantitative analyses under a dissecting microscope. The proportion and total concentration of 

live versus dead organisms was determined using standard movement and response-to-stimuli 

techniques within one hour of collecting the individual samples. Zooplankton samples were also 

fixed and returned to the laboratory for additional taxonomic evaluations.

Live Organisms 10 - 50 μm - Fifteen to twenty liters of well-mixed, but unfiltered water 

from each mesocosm were also collected immediately after filling, to determine concentrations 

of organisms in the 10 to 50 micron size class using three distinct methods: (A) A sub-sample 

was stained using a combination of CMFDA (5-chloromethylfluorescein diacetate) and FDA 

(fluorescein diacetate) as selective live/viable indicators. Stained sub-samples were incubated 

and observed on a Sedgewick Rafter slide using a Leitz Laborlux S modified for epifluorescence. 

(B) A second sub-sample was fixed with standard Lugol's solution for use in taxonomic 

identifications and to serve as a backup sample. (C) A third sub-sample was filtered and frozen 

until analysis of total and active chlorophyll-a by the NASL. (D) Finally, a forth sub-sample was

used to determine chlorophyll-a levels after allowed to regrow under favorable conditions. An 

increase in chlorophyll, or positive regrowth, indicates that viable phytoplankton were in the 

samples, whereas chlorophyll levels at or below detection limits of the laboratory analytical 

method suggests that there was no viable phytoplankton. 

Live Microbes - Additional subsamples of unfiltered water were also collected from each 

mesocosm to determine concentrations of total heterotrophic bacteria and three specific indicator 

pathogens, E. coli, intestinal Enterococci, and toxigenic Vibrio cholerae. Total heterotrophic 

bacteria were enumerated by spread plate method using NWRI agar. The presence and 

abundance of intestinal Enterococci was determined using a commercially available 

chromogenic substrate method. Culturable E. coli concentrations were determined using a 
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standard USEPA method: membrane filtration on modified mTEC agar. Abundances of total 

and toxigenic V. cholerae were calculated by filtration and selection on TCBS agar and 

enumerated using a species-specific RNA colony blot and ctxA DNA colony blot hybridization. 

Viable toxigenic V. cholerae was assayed with a commercial DFA kit specific for serogroup O1

using monoclonal antibodies tagged with fluorescein isothiocyanate.

Toxicity - To evaluate the toxicity of treated water at the completion of each trial, samples 

from each mesocosm were collected and tested for chronic toxicity and for total residual 

chlorine. Filter “backflush” (retenate/filtrate during initial treatment of water) was also tested for 

total residual chlorine. The toxicity protocols and species used were consistent with the USEPA 

methods for Whole Effluent Toxicity (WET). The algal species tested was Isochrysis galbana, 

the fish species was the Sheepshead minnow (Cyprinodon variegatus) while the invertebrate 

species was the Mysid shrimp (Americamysis bahia). 

Chlorine concentration in samples was analyzed immediately upon collection to avoid 

potential loss of oxidant with time. The Standard Methods for the Examination of Water and 

Wastewater Low-Level Amperometric Titration method 4500-Cl D and DPD Colorimetric 

method 4500-Cl G were used to measure Total Residual Oxidants (TRO). A Fischer and Porter 

amperometric titrator was also used for amperometric measurements.

To assess disinfection by-products, a nine-liter carboy of water was drawn at the 

following 4 time-points: T-0 Control inflow, T-0 Treated inflow, T-0 backflush discharge and TF Treated discharge. The carboy of water was immediately sampled for analyses of the 

following compounds: Trihalomethanes (TTHM), Haloacetic Acids (HAA5), Tribromoacetic 

Acid (TBAA), Bromate (Br), Chlorate (ClO3), Sodium (Na, as a metal), and various Nitriles (-

CN group – triple bond). Samples were iced and delivered same-day via courier to the 

Analytical Laboratory Services, Inc. (ALSI) for analysis. 

5.0 Summary of Results

Live Organisms - For essentially all biological categories, the Siemens SiCURETM

BWMS reduced the numbers of live organisms in ballast water to levels below IMO D2 

discharge standards. The only anomaly was found in one trial where Enterococci abundances 

increased slightly in both treated and control water during the 5-day hold time, with a TF value

just over (107.4 + 33.5) the IMO D2 discharge standard of less than 100 cfu/100 ml. However, it 

is important to note the relatively large standard deviation, that the most probably number 

(MPN) method used (Idexx Enterolert kit) to quantify Enterococci commonly over estimate 

abundance when compared to the a traditional membrane filtration method (G. Ditcher, personal 

communication), and in all other test trials (over two different years) Enterococci appeared to be 

successfully treated by the SiCURETM system.

Chronic Toxicity - Toxicity testing was conducted on five treated discharge samples 

between 4/27/10 and 6/15/10. Results indicate that treated ballast water discharge (TF) was not 

chronically toxic to mysid shrimp or Sheepshead Minnows. However the treated water upon 

discharge did significantly inhibit the growth of the algae species, Isochrysis galbana (T-Iso.) for 

three of the test trials (Trial 1 22-27 April, Trial 2 13-18 May, and Trial 5 3-8 June), which is 

reported as “toxic” for this algal assay. These samples had LOECs of 100% and NOECs of 56%. 

All three algae tests with a toxicity response in the undiluted sample (100%) had similar EC50s 

of 70%, 71% and 78% for SIE-03, -05 and -08, respectively.
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Residual Chlorine Analysis - Levels of residual chlorine (or Total Residual Oxidants -

TRO) were below the permissible discharge limit of 0.10 ppm in all TF treated samples. Values 

ranged from 0.06 ppm to below the method detection limit (MDL) of 0.02 ppm. A summary 

table from the completed trial runs and the 24-hour dechlorination run is provided below. TRO 

was immediately measured shipboard using the DPD cholorimetric analysis method. 

Note that Total Residual Chlorine (TRC) is not directly measured using the DPD 

cholorimetric analysis method. The analysis does not distinguish between various oxidants 

(chlorine, bromine, ozone, etc). It reports TRO in chlorine equivalents (in other words, as if all 

oxidant measured were chlorine). In freshwater, after introducing chlorine, we would be 

comfortable calling the residual TRC. However, it is likely that in saltwater, while the majority 

are chlorines, some portion may well be bromines. Thus, we only report TRO.

TRO as measured in the control and treated tanks.

Report ID Run ID Date TRO Treated

Tank

TRO Control

Tank Comment

Trial 1 SIE-03-10 4/27 0.06 ppm

Trial 2 SIE-05-10 5/18 0.08 ppm 0.01 ppm

Trial 3 SIE-06-10 5/25 0.09 ppm 0.03 ppm

Trial 4 SIE-07-10 6/1 ND ND

Trial 5 SIE-08-10 6/8 0.06 ppm 0.04 ppm

24-Hour 

Trial SIE-09-10 6/10 0.59 ppm 0.06 ppm Initial

0.20 ppm Thiosulfate

0.21 ppm Thiosulfate

0.22 ppm Thiosulfate

0.04 ppm Sulfite

0.04 ppm Sulfite

0.02 ppm Sulfite

0.03 ppm Sulfite

0.06 ppm Sulfite

0.03 ppm Sulfite

Notes from dechlorination run. 

1. Thiosulfate treatment did not result in adequate dechlorination at point of discharge.

2. Measured TRO levels in sodium sulfite treated samples were consistently below measured free (active) 

chlorine levels, suggesting interference of sodium sulfite with DPD cholorimetric analysis.

Disinfection By-Products - A summaries of the results for DBP analyses for each trial are 

in the results section below. Reporting detection limits are provided.

Twenty four-hour dechlorintation trial - On June 9-10, 2010, MERC conducted one 

additional trial that required the use of the Siemens dechlorination system. While TF water in all 

5-day hold time trials had total chlorine levels below 0.1 ppm, a short 24-hour hold time resulted 

in measurable levels of chlorine and the subsequent automate dechlorination of the treated water 

upon discharge using Sodium Sulfite (Na2SO3,). For this added trial, total chlorine levels in 

discharged treated water declined in from 0.59 ppm prior to dechlorination, to below 0.1 ppm 
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after the addition sodium bisulfate. Note an attempt at using sodium thiosulfate on discharge 

was not effective, resulting in a final chlorine level of 0.21 ppm.

Mechanical Failures - SIE-10-02-T0 (15 April 2010) The filtration unit on the 

SiCURETM system failed prior to the first sampling mesocosm being completely filled. The unit 

clogged, causing a complete stoppage of flow. Trial SIE-10-02-T0 was therefore canceled. 

SIE-10-06-T0 (20 May 2010) The SiCURETM system experienced a malfunction during startup 

but prior to the filling of the treated tank and sampling mesocosms. Once the issue was resolved, 

testing was re-initiated. In all trials, 10-15 minutes of water flow through the system was 

provided before electrochlorination was initiated. This flow was diverted into the a separated 

ballast tanks and not into the treated test tank.

* Complete datasets and further performance information is available upon request.

6.0 Results

6.1. Trial 1 (SIE-03-10): 22-27 April 2010

Presented as means and standard deviations.

Physical Parameters

TSS mg/l DOC mg/l PC mg/l

T0 Ambient 23.9 (3.7) 2.82 (0.01) 3.44 (0.03)

T0 Enhanced 51.3 (2.4) NA 5.61 (0.61)

Enhanced data is the average of 3 time points (2 reps per time point) during the fill time of the ballast tanks.

Ambient water is sampled at the beginning of the trial and before the water is enhanced. 

Temp oC Salinity psu Dis. Oxygen mg/l Turbidity NTU pH

T-0 Control 14.28 (0.03) 5.97 (0.00) 11.89 (0.03) 17.39 (1.10) 8.5 (0.1)

T-0 Treated 14.36 (0.02) 6.64 (0.00) 16.24 (0.09) 18.46 (1.21) 8.6 (0.1)

T-F Control 14.14 (0.01) 5.95 (0.01) 8.37 (0.02) 3.67 (0.19) 7.8 (0.1)

T-F Treated 14.18 (0.01) 6.61 (0.01) 10.93 (0.01) 6.56 (0.09) 8.0 (0.1)

Live Organisms > 50 μm

T0 #/m3 TF #/m3

Control 124,000 (5,000) *223,667 (29,501)

Treated 4.5 (7) 5 (4.5)

*Note large increase between T0 and TF in Control tank (reproduction and hatching of eggs).

*TF Control *TF Treated

Copepod nauplii Copepoda

Calanoida (Acartia sp.) Rotifera

Cirripedia nauplii

Harpacticoida

* Up to four top taxa listed in order of abundance.
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Live Organisms 10 - 50 μm

Vital Stain Results - It is important to note that the specific approach used underestimates 

the abundances of live organisms in this size class because it has been found that not all live 

organisms reliably take up these stains. 

T0 #/ml TF #/ml

Control 5,297 (776) 1,113 (225)

Treated 29 (19) 0 (0)

Dominant species Type Other

Heterocapsa rotundatum Dinoflagellate Small but abundant

Gymnodinium sp. Dinoflagellate

Navicula sp. Diatom

Active Chlorophyll-a - Chlorophyll is used as ancillary data and as a general

presence/absence indicator of viable photosynthetic organisms. 

T0 μg/l TF μg/l RG μg/l

Control 39.84 (11.77) 5.63 (0.50) 1.19 (0.13)

Treated 0.32 (0.13) 0.21 (0.02) 0.00 (0.01)

RG = after re-growth assay; MDL = 0.56 μg/l

Live Microbes

cfu = colony forming units

E. coli T0 cfu/100ml TF cfu/100ml

Control 3.4 (1.52) 0.6 (1.34)

Treated 0 (0) 0 (0)

Enterococci T0 NPM/100ml TF MPN/100ml

Control 3.92 (1.38) 9.06 (2.96)

Treated 1 (0.71) 1.2 (0.45)

MPN = most probably number estimate determined by the Idexx Enterolert kit.

V. cholerae – No detectable culturable toxigenic Vibrio cholerae were detected in any 

samples during any of the trials.

Heterotrophic 

Bacteria 

T0 (sd)

cfu/1ml

TF (sd)

 cfu/1ml

Control 1,518 (373.6) 808 (190.66)

Treated 2.2 (3.58) 29,120 (2,184.49)
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Toxicity Summaries

Residual Chlorine Analysis - Levels of residual chlorine (or total residual oxidants -

TRO) were below the permissible discharge limit of 0.10 ppm in all TF treated samples. Values 

ranged from 0.06 ppm to below the method detection limit (MDL) of 0.02 ppm.

Chronic Toxicity - Results showed that ballast water discharge was not chronically toxic 

to either mysids or sheepshead minnows. All samples, however, were chronically toxic to the 

marine algal species Isochrysis galbana with a statistically significant inhibition in growth in 

treated ballast discharge compared to controls.

Disinfection By-Products (μg/l)

Control Treated BW Treated RDL/MRL

T0 T0 T0 TF

Trihalomethanes 0 91.2 ND 293 0.5

Trichloromethane < 0.5 < 0.5 ND < 0.5 0.5

Bromodichloromethane < 0.5 2.7 ND 3.8 0.5

Dibromochloromethane < 0.5 20.7 ND 28.2 0.5

Tribromomethane < 0.5 67.8 ND 261 0.5

Haloacetic Acids 0 87.4 ND 197 1.0

Monochloroacetic acid < 2.0 < 2.0 ND < 2.0 2.0

Dichloroacetic acid < 1.0 1.2 ND < 1.0 1.0

Trichloroacetic acid < 1.0 < 1.0 ND < 1.0 1.0

Bromochloroacetic acid < 1.0 5 ND < 1.0 1.0

Monobromoacetic acid < 1.0 4.5 ND < 1.0 1.0

Dibromoacetic acid < 1.0 72.2 ND < 1.0 1.0

Tribromoacetic acid < 1.0 4.5 ND 197 1.0

Other ND

Sodium chlorate < 10 340 ND 340 10

Sodium bromate < 50.0 < 50.0 ND < 50.0 50.0

Monochloroacetonitrile <0.5 <0.5 ND <0.5

Dichloroacetonitrile <0.5 <0.5 ND <0.5 0.5

Monobromoacetonitrile <0.5 <0.5 ND <0.5

Dibromoacetonitrile <0.5 18 ND <0.5 0.5

BW = backwash; RDL = reporting detection limit; MRL = method reporting limit
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6.2. Trial 2 (SIE-05-10): 13-18 May 2010

Presented as means and standard deviations.

Physical Parameters

TSS mg/l DOC mg/l POC mg/l

T0 Ambient 11.5 (1.0) 3.41 (0.13) 1.11 (0.03)

T0 Enhanced 65.2 (8.5) NA 5.88 (0.79)

Enhanced data is the average of 3 time points (2 reps per time point) during the fill time of the ballast tanks.

Ambient water is sampled at the beginning of the trial and before the water is enhanced. 

Temp oC Salinity psu Dis. Oxygen mg/l Turbidity NTU pH

T-0 Control 15.15 (0.01) 8.19 (0.02) 8.54 (0.06) 15.60 (0.87) 7.3 (0.1)

T-0 Treated 15.20 (0.01) 8.84 (0.01) 9.02 (0.02) 15.11 (1.24) 7.3 (0.1)

T-F Control 16.53 (0.06) 8.15 (0.00) 6.92 (0.06) 3.49 (0.23) 7.2 (0.2)

T-F Treated 16.52 (0.05) 8.76 (0.00) 8.74 (0.03) 5.27 (0.42) 7.1 (0.1)

Live Organisms > 50 μm

T0 #/m3 *TF #/m3

Control 60,000 (10,500) 90,500 (10,000) ŧ

Treated 4.2 (7) 0.2 (0.4)

*Note moderate increase between T0 and TF in Control tank (reproduction and hatching of eggs).

*TF Control *TF Treated

Copepod nauplii Polycheata (Spionidae)

Calanoida (Acartia sp.)

Polychaeta (Spionidae)

Harpacticoida

* Up to four top taxa listed in order of abundance.

Live Organisms 10 - 50 μm

Vital Stain Results - It is important to note that the specific approach used underestimates 

the abundances of live organisms in this size class because it has been found that not all live 

organisms reliably take up these stains. 

T0 #/ml TF #/ml

Control 1,915 (511) 3,182 (725)

Treatment 1.7 (1.2) 6 (3.8)

Dominant species Type Other

Heterocapsa rotundatum Dinoflagellate

Gymnodinium sp. Dinoflagellate

Thalassiosira gravida Diatom chain-forming

Navicula sp. Diatom
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Active Chlorophyll-a - Chlorophyll is used as ancillary data and as a general 

presence/absence indicator of viable photosynthetic organisms. 

T0 μg/l TF μg/l RG μg/l

Control 8.79 (0.48) 1.89 (0.06) 5.95 (3.11)

Treated 0.08 (0.01) 0.03 (0.01) 0.08 (0.09)

RG = after re-growth assay

MDL = 0.56 μg/l

Live Microbes

cfu = colony forming units

E. coli T0 cfu/100ml TF cfu/100ml

Control 4.6 (1.82) 0 (0)

Treated 0 (0) 1 (1.41)

Enterococci T0 MPN/100ml TF MPN/100ml

Control 8.78 (21.2) 49.34 (26.54)

Treated 2.02 (1.45) 107.4 (33.5)

MPN = most probable number estimates determined by the Idexx Enterolert kit. Note that this MPN is not a direct 

cfu count and Enterolert MPN values are commonly found to be higher than the traditional membrane filtration 

method used to estimate Enterococci abundances (G. Ditcher, Idexx).

V. cholerae – No detectable culturable toxigenic Vibrio cholerae were detected in any 

samples during any of the trials.

Heterotrophic 

Bacteria T0 cfu/1ml TF cfu/1ml

Control 146 (80) 503.33 (187.75)

Treated 0 (0) 10,520 (4,447.13)

Toxicity Summaries

Residual Chlorine Analysis - Levels of residual chlorine (or total residual oxidants -

TRO) were below the permissible discharge limit of 0.10 ppm in all TF treated samples. Values 

ranged from 0.06 ppm to below the method detection limit (MDL) of 0.02 ppm.

Chronic Toxicity - Results showed that ballast water discharge was not chronically toxic 

to either mysids or sheepshead minnows. All samples, however, were chronically toxic to the 

marine algal species Isochrysis galbana with a statistically significant inhibition in growth in 

treated ballast discharge compared to controls.
MERC ER02-10

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Disinfection By-Products (μg/l)

Control Treated BW Treated RDL/MRL

T0 T0 T0 TF

Trihalomethanes 0 106.6 ND 227.8 0.5

Trichloromethane < 0.5 < 0.5 ND < 0.5 0.5

Bromodichloromethane < 0.5 1.6 ND 2.5 0.5

Dibromochloromethane < 0.5 13.5 ND 24.3 0.5

Tribromomethane < 0.5 91.5 ND 201 0.5

Haloacetic Acids 1.4 62.9 ND 385.6 1.0

Monochloroacetic acid < 2.0 < 2.0 ND < 2.0 2.0

Dichloroacetic acid < 1.0 < 1.0 ND < 1.0 1.0

Trichloroacetic acid < 1.0 < 1.0 ND < 1.0 1.0

Bromochloroacetic acid < 1.0 3.3 ND < 1.0 1.0

Monobromoacetic acid < 1.0 3.1 ND 1 1.0

Dibromoacetic acid < 1.0 53 ND 10.6 1.0

Tribromoacetic acid 1.4 3.5 ND 374 1.0

Other ND

Sodium chlorate < 10 250 ND 250 10

Sodium bromate < 50.0 < 50.0 ND < 50.0 50.0

Monochloroacetonitrile <0.5 <0.5 ND <0.5

Dichloroacetonitrile <0.5 0.86 ND <0.5 0.5

Monobromoacetonitrile <0.5 <0.5 ND <0.5

Dibromoacetonitrile <0.5 24 ND 4.4 0.5

BW = backwash

RDL = reporting detection limit

MRL = method reporting limit

6.3. Trial 3 (SIE-06-10): 20-25 May 2010

Presented as means and standard deviations.

Physical Parameters

TSS mg/l DOC mg/l POC mg/l

T0 Ambient 19.7 (3.6) 2.96 (0.00) 1.28 (0.01)

T0 Enhanced 56.2 (13.5) NA 4.76 (0.92)

Enhanced data is the average of 3 time points (2 reps per time point) during the fill time of the ballast tanks.

Ambient water is sampled at the beginning of the trial and before the water is enhanced. 

Temp oC Salinity psu Dis. Oxygen mg/l Turbidity NTU pH

T-0 Control 15.14 (0.02) 9.80 (0.02) 6.47 (0.39) 15.68 (1.30) 7.1 (0.1)

T-0 Treated 15.18 (0.00) 10.35 (0.00) 7.91 (0.01) 14.95 (1.01) 7.0 (0.1)

T-F Control 19.83 (0.01) 9.75 (0.00) 4.82 (0.02) 3.06 (0.10) 7.1 (0.1)

T-F Treated 19.97 (0.01) 10.37 (0.00) 7.55 (0.01) 6.61 (0.09) 7.0 (0.1)
MERC ER02-10

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Live Organisms > 50 μm

T0 #/m3 TF #/m3

Control 50,500 (10,000) 35,666 (2,350)

Treated 9 (7) 9 (3.5)

*TF Control *TF Treated

Copepod nauplii Bivalve larvae

Polychaeta (Spionidae) Copepoda

Calanoida (Acartia sp, Eurytemora sp.) Turbellaria

Harpacticoida

* Up to four top taxa listed in order of abundance.

Live Organisms 10 - 50 μm

Vital Stain Results - It is important to note that the specific approach used underestimates 

the abundances of live organisms in this size class because it has been found that not all live 

organisms reliably take up these stains. 

T0 #/ml TF #/ml

Control 1,088 (194) 137 (8)

Treatment 1.7 (1.2) 0 (0)

Dominant species Type Other

Heterocapsa rotundatum Dinoflagellate

Gymnodinium sp. Dinoflagellate

Thalassiosira gravida Diatom chain-forming

Navicula sp. Diatom

Active Chlorophyll-a - Chlorophyll is used as ancillary data and as a general 

presence/absence indicator of viable photosynthetic organisms.

T0 μg/l TF μg/l RG μg/l

Control 3.07 (0.09) 0.91 (0.02) 0.12 (0.09)

Treated 0.24 (0.17) 0.13 (0.02) 0.00 (0.00)

RG = after re-growth assay; MDL = 0.56 μg/l

Live Microbes

cfu = colony forming units

E. coli T0 cfu/100ml TF cfu/100ml

Control 0 (0) 2.2 (1.5)

Treated 0 (0) 0 (0)

Enterococci T0 MPN/100ml TF MPN/100ml

Control 16.64 (4.08) 70.42 (29.77)

Treated 5.8 (1.9) 34.68 (8.59)

MPN = most probably number estimate determined by the Idexx Enterolert kit.
MERC ER02-10

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V. cholerae – No detectable culturable toxigenic Vibrio cholerae were detected in any 

samples during any of the trials.

Heterotrophic 

Bacteria T0 cfu/1ml TF cfu/1ml

Control 950 (300) 55 (31)

Treated 0 (0) 13,780 (2,560)

Toxicity Summaries

Residual Chlorine Analysis - Levels of residual chlorine (or total residual oxidants -

TRO) were below the permissible discharge limit of 0.10 ppm in all TF treated samples. Values 

ranged from 0.06 ppm to below the method detection limit (MDL) of 0.02 ppm.

Chronic Toxicity - Results showed that ballast water discharge was not chronically toxic 

to any of the three tested species.

Disinfection By-Products (μg/l)

Control Treated BW Treated RDL/MRL

T0 T0 T0 TF

Trihalomethanes 0 27 0.63 168.2 0.5

Trichloromethane < 0.5 < 0.5 < 0.5 < 0.5 0.5

Bromodichloromethane < 0.5 1.2 < 0.5 2.3 0.5

Dibromochloromethane < 0.5 10.6 < 0.5 17.9 0.5

Tribromomethane < 0.5 15.2 0.63 148 0.5

Haloacetic Acids 0 71.1 1.9 6.9 1.0

Monochloroacetic acid < 2.0 < 2.0 < 2.0 < 2.0 2.0

Dichloroacetic acid < 1.0 < 1.0 < 1.0 < 1.0 1.0

Trichloroacetic acid < 1.0 < 1.0 < 1.0 1.4 1.0

Bromochloroacetic acid < 1.0 2.9 < 1.0 < 1.0 1.0

Monobromoacetic acid < 1.0 1.4 < 1.0 < 1.0 1.0

Dibromoacetic acid < 1.0 28.4 < 1.0 5.5 1.0

Tribromoacetic acid < 4.0 38.4 1.9 0 1.0

Other

Sodium chlorate < 10 170 < 10 < 10 10

Sodium bromate < 50.0 < 50.0 < 50.0 < 50.0 50.0

Monochloroacetonitrile <0.5 <0.5 <0.5 <0.5

Dichloroacetonitrile <0.5 <0.5 <0.5 <0.5 0.5

Monobromoacetonitrile <0.5 <0.5 <0.5 <0.5

Dibromoacetonitrile <0.5 15 <0.5 7.4 0.5

BW = backwash

RDL = reporting detection limit

MRL = method reporting limit
MERC ER02-10

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6.4. Trial 4 (SIE-07-10): 27 May – 1 June 2010

Presented as means and standard deviations.

Physical Parameters

TSS mg/l DOC mg/l POC mg/l

T0 Ambient 12.7 (0.4) 3.16 (0.02) 1.29 (0.04)

T0 Enhanced 57.9 (1.7) NA 5.36 (0.19)

Enhanced data is the average of 3 time points (2 reps per time point) during the fill time of the ballast tanks.

Ambient water is sampled at the beginning of the trial and before the water is enhanced. 

Temp oC Salinity psu Dis. Oxygen mg/l Turbidity NTU pH

T-0 Control 17.40 (0.03) 8.81 (0.03) 7.09 (0.10) 15.84 (1.11) 6.9 (0.1)

T-0 Treated 17.48 (0.02) 9.42 (0.00) 5.47 (0.04) 16.09 (1.21) 7.0 (0.1)

T-F Control 19.53 (0.01) 8.87 (0.00) 5.18 (0.10) 2.22 (0.08) 7.2 (0.1)

T-F Treated 19.69 (0.01) 9.48 (0.00) 5.57 (0.02) 6.07 (0.13) 7.2 (0.1)

Live Organisms > 50 μm

T0 #/m3 TF #/m3

Control 113,333 (14,154) 63,500 (9,750)

Treated 13 (12) 1.8 (0.8)

*TF Control *TF Treated

Calanoida (Eurytemora sp.) Copepoda

Copepod nauplii Bivalve larva

Polychaeta (Spionidae)

Bivalve larvae

* Up to four top taxa listed in order of abundance.

Live Organisms 10 - 50 μm 

Vital Stain Results - It is important to note that the specific approach used underestimates 

the abundances of live organisms in this size class because it has been found that not all live 

organisms reliably take up these stains. 

T0 #/ml TF #/ml

Control 1,544 (103) 1,026 (133)

Treatment 1 (1) 1.2 (0.8)

Dominant species Type Other

Prorocentrum minimum Dinoflagellate

Heterocapsa rotundatum Dinoflagellate

Gymnodinium estuarale Dinoflagellate first time detected in 2010

Thalassiosira sp. Diatom chain-forming

Navicula sp. Diatom
MERC ER02-10

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Active Chlorophyll-a - Chlorophyll is used as ancillary data and as a general 

presence/absence indicator of viable photosynthetic organisms.

T0 μg/l TF μg/l RG μg/l

Control 6.42 (0.78) 1.08 (0.04) 1.41 (0.47)

Treated 0.05 (0.01) 0.02 (0.01) 0.00 (0.00)

RG = after re-growth assay

MDL = 0.56 μg/l

Live Microbes

cfu = colony forming units

E. coli T0 cfu/100ml TF cfu/100ml

Control 2.2 (2.49) 0 (0)

Treated 0 (0) 0 (0)

Enterococci T0 MPN/100ml TF MPN/100ml

Control 10 (4) 11.62 (3.75)

Treated 2.46 (2.16) 57.96 (30.54)

MPN = most probably number estimate determined by the Idexx Enterolert kit.

V. cholerae – No detectable culturable toxigenic Vibrio cholerae were detected in any 

samples during any of the trials.

Heterotrophic 

Bacteria T0 cfu/1ml TF cfu/1ml

Control 470 (176) 190 (63.07)

Treated 1.4 (1.43) 7,630 (4,181)

Toxicity Summaries

Residual Chlorine Analysis - Levels of residual chlorine (or total residual oxidants -

TRO) were below the permissible discharge limit of 0.10 ppm in all TF treated samples. Values 

ranged from 0.06 ppm to below the method detection limit (MDL) of 0.02 ppm.

Chronic Toxicity - Results showed that ballast water discharge was not chronically toxic 

to any of the three tested species.
MERC ER02-10

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Disinfection By-Products (μg/l)

Control Treated BW Treated RDL/MRL

T0 T0 T0 TF

Trihalomethanes 0 98.2 0 281.2 0.5

Trichloromethane < 0.5 < 0.5 < 0.5 < 0.5 0.5

Bromodichloromethane < 0.5 1.6 < 0.5 2.6 0.5

Dibromochloromethane < 0.5 14.9 < 0.5 25.6 0.5

Tribromomethane < 0.5 81.7 < 0.5 253 0.5

Haloacetic Acids 0 56.7 0 117.6 1.0

Monochloroacetic acid < 2.0 < 2.0 < 2.0 < 2.0 2.0

Dichloroacetic acid < 1.0 < 1.0 < 1.0 < 1.0 1.0

Trichloroacetic acid < 1.0 < 1.0 < 1.0 < 1.0 1.0

Bromochloroacetic acid < 1.0 4.1 < 1.0 < 1.0 1.0

Monobromoacetic acid < 1.0 3.4 < 1.0 < 1.0 1.0

Dibromoacetic acid < 1.0 49.2 < 1.0 10.6 1.0

Tribromoacetic acid < 4.0 0 < 4.0 107 1.0

Other

Sodium chlorate < 10 180 < 10 240/200 10

Sodium bromate < 50.0 < 50.0 < 50.0 < 50.0 50.0

Monochloroacetonitrile <0.5 <0.5 <0.5 <0.5

Dichloroacetonitrile <0.5 <0.5 <0.5 <0.5 0.5

Monobromoacetonitrile <0.5 <0.5 <0.5 <0.5

Dibromoacetonitrile <0.5 26 <0.5 12 0.5

BW = backwash

RDL = reporting detection limit

MRL = method reporting limit
MERC ER02-10

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6.5. Trial 5 (SIE-08-10): 3-8 June 2010

Presented as means and standard deviations.

Physical Parameters

TSS mg/l DOC mg/l POC mg/l

T0 Ambient 17.1 (5.1) 3.76 (0.11) 1.56 (0.18)

T0 Enhanced 55.0 (5.6) NA 5.39 (0.52)

Enhanced data is the average of 3 time points (2 reps per time point) during the fill time of the ballast tanks.

Ambient water is sampled at the beginning of the trial and before the water is enhanced. 

Temp oC Salinity psu Dis. Oxygen mg/l Turbidity NTU pH

T-0 Control 20.48 (0.02) 7.41 (0.00) 4.82 (0.15) 15.96 (1.13) 7.1 (0.1)

T-0 Treated 20.52 (0.01) 6.99 (0.01) 7.89 (0.01) 16.05 (1.14) 7.1 (0.1)

T-F Control 20.13 (0.02) 7.50 (0.00) 3.13 (0.04) 1.32 (0.07) 7.0 (0.1)

T-F Treated 20.27 (0.03) 6.34 (0.01) 7.94 (0.00) 7.22 (0.18) 7.0 (0.1)

Live Organisms > 50 μm

T0 #/m3 TF #/m3

Control 175,000 (11,000) 94,500 (8,250)

Treated 221 (59) 8 (3)

*TF Control *TF Treated

Copepod nauplii Copepoda

Bivalve larvae Polychaeta (Spionidae)

Spionidae

Calanoida (Eurytemora sp.)

* Up to four top taxa listed in order of abundance.

Live Organisms 10 - 50 μm

Vital Stain Results - It is important to note that the specific approach used underestimates 

the abundances of live organisms in this size class because it has been found that not all live 

organisms reliably take up these stains. 

T0 #/ml TF #/ml

Control 1,511 (271) 757 (145)

Treatment 1.7 (1.2) 2.2 (1.5)

Dominant species Type Other

Prorocentrum minimum Dinoflagellate

Thalassiosira sp. Diatom chain-forming

Gyrodinium estuarale Dinoflagellate

Navicula sp. Diatom

Amphora sp. Diatom
MERC ER02-10

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Active Chlorophyll-a - Chlorophyll is used as ancillary data and as a general 

presence/absence indicator of viable photosynthetic organisms.

T0 μg/l TF μg/l RG μg/l

Control 3.42 (0.12) 0.44 (0.14) 0.97 (0.36)

Treated 0.04 (0.01) 0.01 (0.00) 0.00 (0.00)

RG = after re-growth assay

MDL = 0.56 μg/l

Live Microbes

cfu = colony forming units

E. coli T0 cfu/100ml TF cfu/100ml

Control 13.4 (5.5) 0 (0)

Treated 0 (0) 0 (0)

Enterococci T0 MPN/100ml TF MPN/100ml

Control 113.94 (38.9) 2.42 (0.58)

Treated 1.02 (1.45) 1 (1)

MPN = most probably number estimate determined by the Idexx Enterolert kit.

V. cholerae – No detectable culturable toxigenic Vibrio cholerae were detected in any 

samples during any of the trials.

Heterotrophic 

Bacteria T0 cfu/1ml TF cfu/1ml

Control 577 (149) 466 (671)

Treated 2.3 (2.5) 3,950 (884)

Toxicity Summaries

Residual Chlorine Analysis - Levels of residual chlorine (or total residual oxidants -

TRO) were below the permissible discharge limit of 0.10 ppm in all TF treated samples. Values 

ranged from 0.06 ppm to below the method detection limit (MDL) of 0.02 ppm.

Chronic Toxicity - Results showed that ballast water discharge was not chronically toxic 

to either mysids or sheepshead minnows. 

All samples, however, were chronically toxic to the marine algal species Isochrysis 

galbana with a statistically significant inhibition in growth in treated ballast discharge compared 

to controls.
MERC ER02-10

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Disinfection By-Products (μg/l)

Control Treated BW Treated RDL/MRL

T0 T0 T0 TF

Trihalomethanes 0 241.4 0 89.6 0.5

Trichloromethane < 0.5 < 0.5 < 0.5 < 0.5 0.5

Bromodichloromethane < 0.5 2.6 < 0.5 3.3 0.5

Dibromochloromethane < 0.5 119.8 < 0.5 24.5 0.5

Tribromomethane < 0.5 119 < 0.5 61.8 0.5

Haloacetic Acids 0 143.8 0 95.6 1.0

Monochloroacetic acid < 2.0 < 2.0 < 2.0 < 2.0 2.0

Dichloroacetic acid < 1.0 < 1.0 < 1.0 < 1.0 1.0

Trichloroacetic acid < 1.0 < 1.0 < 1.0 < 1.0 1.0

Bromochloroacetic acid < 1.0 3.5 < 1.0 < 1.0 1.0

Monobromoacetic acid < 1.0 3.2 < 1.0 < 1.0 1.0

Dibromoacetic acid < 1.0 37.1 < 1.0 8.9 1.0

Tribromoacetic acid < 4.0 100 < 4.0 86.7 1.0

Other

Sodium chlorate < 10 295/240 < 10 < 10/297 10

Sodium bromate < 50.0 < 50.0 < 50.0 < 50.0 50.0

Monochloroacetonitrile <0.5 <0.5 <0.5 <0.5

Dichloroacetonitrile <0.5 <0.5 <0.5 <0.5 0.5

Monobromoacetonitrile <0.5 <0.5 <0.5 <0.5

Dibromoacetonitrile <0.5 24 <0.5 8.5 0.5

BW = backwash

RDL = reporting detection limit

MRL = method reporting limit

6.6. Twenty four-hour Dechlorination Trial: 9-10 June 2010

Presented as means and standard deviations.

Physical Parameters

TSS mg/l DOC mg/l POC mg/l

T0 Ambient 33.4 (9.6) 3.11 (0.12) 2.06 (0.09)

T0 Enhanced NA NA NA

Enhanced data is the average of 3 time points (2 reps per time point) during the fill time of the ballast tanks.

Ambient water is sampled at the beginning of the trial and before the water is enhanced. 

Temp oC Salinity psu Dis. Oxygen mg/l Turbidity NTU pH

T-0 Control 21.03 (0.08) 8.39 (0.02) 6.38 (0.22) 3.22 (0.12) 7.5 (0.1)

T-0 Treated 21.15 (0.04) 9.01 (0.01) 7.35 (0.02) 7.53 (0.20) 7.0 (0.1)

T-F Control 20.51 (0.04) 8.41 (0.00) 5.76 (0.03) 2.96 (0.14) 7.0 (0.1)

T-F Treated 20.74 (0.03) 9.04 (0.00) 7.32 (0.01) 7.29 (0.10) 7.0 (0.1)
MERC ER02-10

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Live Organisms > 50 μm

T0 Avg(sd) #/m3 TF Avg(sd) #/m3

Control 160,500 (9,750) 112,500 (5,000)

Treated 17 (7) 1.2 (2)

* Up to four top taxa listed in order of abundance.

Live Organisms 10 - 50 μm

Vital Stain Results - It is important to note that the specific approach used underestimates 

the abundances of live organisms in this size class because it has been found that not all live 

organisms reliably take up these stains. 

T0 #/ml TF #/ml

Control 4,593 (823) 3,355 (149)

Treatment 0 (0) 0 (0)

Dominant species Type Other

Prorocentrum minimum Dinoflagellate

Thalassiosira sp. Diatom chain-forming

Gyrodinium estuarale Dinoflagellate

Cyclotella glomerata Diatom chain-forming

Skeletonema costatum Diatom chain-forming

Heterocapsa triquerta Dinoflagellate

Navicula sp. Diatom

Nitzschia sp. Diatom

Active Chlorophyll-a - Chlorophyll is used as ancillary data and as a general 

presence/absence indicator of viable photosynthetic organisms.

T0 μg/l TF μg/l RG μg/l

Control 12.33 (0.77) 9.66 (0.16) NA

Treated 0.04 (0.01) 0.01 (0.00) NA

RG = after re-growth assay

MDL = 0.56 μg/l

*TF Control *TF Treated

Copepod nauplii Copepoda

Bivalve larvae Polychaeta (Spionidae)

Spionidae

Calanoida (Eurytemora sp.)
MERC ER02-10

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Live Microbes

cfu = colony forming units

E. coli T0 cfu/100ml TF cfu/100ml

Control 10.33 (9.29) 2.67 (2.52)

Treated 0 (0) 0 (0)

Enterococci T0 MPN/100ml TF MPN/100ml

Control 5.13 (2.05) 8.9 (2.88)

Treated 0.33 (0.58) 0.33 (0.58)

MPN = most probably number estimate determined by the Idexx Enterolert kit.

V. cholerae – No detectable culturable toxigenic Vibrio cholerae were detected in any 

samples during any of the trials.

Heterotrophic 

Bacteria T0 cfu/1ml TF cfu/1ml

Control 2,180 (383) 631.67 (218.68)

Treated 3.5 (6.06) 0 (0)

Toxicity Summaries

Residual Chlorine Analysis – On June 9-10, 2010, MERC assisted Siemens with the 

testing of their dechlorination system. A 24-hour trial resulted in successful dechlorination of 

the treated tank using sodium bisulfate (a decline in total chlorine levels from 0.59 ppm to below 

0.1 ppm – the EPA discharge standard). Note that using a sodium thiosulfate treatment resulted 

in a final total chlorine level of 0.22 ppm.

Chronic Toxicity – Ballast water was tested after treatment with a higher concentration of 

chlorine followed by an in-line de-chlorination. Ballast water was collect in the same manner 

and location as previous tests. All three species (mysid, fish and algae) were tested for toxicity. 

There was no statistically significant toxicological effect seen in any of these three test species.
MERC ER02-10

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Disinfection By-Products (μg/l)

Control Treated BW Treated

RDL/M

RL

T0 T0 T0 TF

Trihalomethanes 0 88.4 0 238.9 0.5

Trichloromethane < 0.5 < 0.5 < 0.5 < 0.5 0.5

Bromodichloromethane < 0.5 1.4 < 0.5 2.1 0.5

Dibromochloromethane < 0.5 15 < 0.5 22.8 0.5

Tribromomethane < 0.5 72 < 0.5 214 0.5

Haloacetic Acids 0 118.7 0 193.3 1.0

Monochloroacetic acid < 2.0 < 2.0 < 2.0 < 2.0 2.0

Dichloroacetic acid < 1.0 < 1.0 < 1.0 < 1.0 1.0

Trichloroacetic acid < 1.0 < 1.0 < 1.0 < 1.0 1.0

Bromochloroacetic acid < 1.0 2.5 < 1.0 3.1 1.0

Monobromoacetic acid < 1.0 2.5 < 1.0 3.8 1.0

Dibromoacetic acid < 1.0 25 < 1.0 39.4 1.0

Tribromoacetic acid < 4.0 88.7 < 4.0 147 1.0

Other

Sodium chlorate < 10 276/340 < 10/390 233/330 10

Sodium bromate < 50.0 < 50.0 < 50.0 < 50.0 50.0

Monochloroacetonitrile <0.5 <0.5 <0.5 <0.5

Dichloroacetonitrile <0.5 <0.5 <0.5 <0.5 0.5

Monobromoacetonitrile <0.5 <0.5 <0.5 <0.5

Dibromoacetonitrile <0.5 28 <0.5 29 0.5

BW = backwash

RDL = reporting detection limit

MRL = method reporting limit
MERC ER02-10

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7.0 Acknowledgments

The MERC Testing Team included J. Barnes, M. Carroll, D. Fisher, B. Haley, A. Huq, R. 

Kanzleiter, T. Mullady, G. Ruiz, G. Smith, D. Sparks, M. Tamburri. E. Taviani, M. Wilkinson, 

L. Yonkos, and G. Ziegler. Test protocols were developed in conjunction with A. Cangelosi, the 

Great Ships Initiative, Bundesamt fuer Seeschifffahrt und Hydrographie (BSH) and M. Veldhuis. 

We wish thank the crew of the MV Cape Washington who provided critical input and support on 

all aspects of these trials, and the Maryland Port Administration and U.S. Maritime 

Administration for funding and supporting this ballast water treatment evaluation.

16 September 2010

16 September 2010

Date Approved By: Dr. Mario Tamburri

MERC Executive Director

Date Approved By: Ross Kanzleiter

MERC Program Coordinator and

Chief Engineer