New Data Assessing the Concentrations and Potential Toxicity of Copper in Sediments

Bob Dwyer & Hal Stillman, Copper Alliance Svein Midtoy, Lerow AS; Daniel Steitz, WielandAlex Brown, EcoSea SA

Engineering Testing of Unstocked Copper Alloy Pen, Norway, May 2015 to June 2017

Single Pen (NS 9415-certified) deployed in central Norway for mechanical, durability, corrosion and other engineering tests by potential customer

Pen never stocked during deployment

As part of assessing potential of deployment of Copper Alloy pens at farms seeking ASC certification, buildup of copper in sediments was assessed:

• Pen testing site had never been used previously, so sediments had only natural crustal-derived copper and other metal concentrations

• Pen site sediments sampled initially in May, 2015, prior to pen deployment

• Sediments sampled again in June 2017, just after pen removal:-- inside the ASC’s Allowable Zone of Effect (AZE – 25 m beyond float ring)-- outside AZE

European Aquaculture Society – EAS17, Dubrovnik, October 18, 20172

EcoSea Integrated Copper Alloy Pen Design NS-9415 - certified

European Aquaculture Society3

Pen Test Site and Post-Deployment Sediment Sample Locations

European Aquaculture Society – EAS17, Dubrovnik, October 18, 20174

Total Copper Concentrations in Sediments, Pre- vs Post-Deployment (inside vs outside AZE)

European Aquaculture Society – EAS17, Dubrovnik, October 18, 20175

Pre-Deployment

InsideAZE

Outside AZE

66.7

Tota

l Cop

per,

mg/

Kg

Total Copper in Sediment - Conclusions

No evidence of any pre- vs. post-deployment increase, over the 25 months.

The medians (thin horizontal lines inside each box) of all three groups (medians eliminate the undue influence of the outlier…) are in the range of 7 to 11 mg/Kg – no differences.

All samples <50% of the ASC’s 34 mg/Kg limit.(except for one pre-deployment outlier)

European Aquaculture Society – EAS17, Dubrovnik, October 18, 20176

Bioavailable Copper in Sediments

Bioavailable copper – what remains in pore water after binding to Organic Matter, and Sulfides

Many countries changing to regulating metals in sediments based on Bioavailable fraction, rather than Total metal:

• European Commission’s accepted sediment PNEC for Copper based on Bioavailable Fraction; many Member States evaluating Bioavailable thresholds under Water Framework Directive.

• Australia (ANZECC) sediment Trigger Value based on Organic Carbon, % silt-clay

Bioavailable metals in sediments at the Norway site – still at the laboratory!

European Aquaculture Society – EAS17, Dubrovnik, October 18, 20177

Main factors governing bioavailability for metals in sediments

AVSAVS is important in reduced sediments and forms insoluble MeScomplexes

Organic carbonImportant absorption phase in absence of AVS

Fe/Mn oxidesAbsorbing and scavenging properties (oxicsediments)

CECPlays similar role as in soils

Factor 1 Factor 2 Factor 3 Factor 4

ASC, August 20158

9

Members of the Project Team

Hal StillmanTechnology Development and Transferhal.stillman@copperalliance.org+1 917 345 1409

Martin HeidenreichBusiness DevelopmentMartin.Heidenreich@wieland.de+ 49 731 944 2757

Hallgeir BremnesCEOboss@lerow.no+47 901 58 802

Nicolás PuelmaMarket Developmentnpuelma@codelco.cl+56 2 2690 3035

Javier TapiaCOOjtapia@ecosea.cl+56 65 2313650

Lerow executed the project through

Leroy

Kent-Roger WahlvågMobil 97541078www.akerbla.no

Thank You!

| Presentation title and date

For more information please contact:

Robert Dwyerrobert.dwyer@copperalliance.org

Or visit:

CuAquaculture.org