Presenter Allan McMurray Conestoga-Rovers & Associates (CRA)

Presenter Allan McMurray Conestoga-Rovers & Associates (CRA) Presentation Pilot Scale Study Removal of Uranium, Radium-226 and Arsenic from Impacted Leachate by Reverse Osmosis Session: Stream B - Innovative Assessment and Remediation Technologies 2:30 pm May 1 st, 2012 for Real Property Institute of Canada Federal Contaminated Sites National Workshop 2012 Toronto, ON

Presentation Outline Welcome Waste Management Facility CRA Design Approach On-Site Pilot Testing CRA Water Treatment Plant Design Summary Acknowledgements

Presentation Outline Welcome Waste Management Facility Site Background Influent Water Quality CRA Design Approach Review of Potential Treatment Alternatives Bench Scale Evaluation of Preferred Treatment Concept On-Site Pilot Testing Experimental Design On-Site Testing of Reverse Osmosis Membranes Results CRA Water Treatment Plant Design Summary

Welcome Site - Background Currently, Groundwater/surface water/impacted water at Welcome waste management facility (WMF) treated with ferric chloride and discharged to Lake Ontario Expected importation of additional low-level waste to site will result in additional loading of contaminants

Welcome WMF Approximately 1.2 million cubic meters of low-level waste to be contained in the Welcome Long-Term WMF

Preliminary Estimate of Impacted Water Generation 400,000 Annual Wastewater Generation Based on Cameco Annual Monitoring Reports 350,000 Projected Wastewater Generation Based on 31 Year Average Precipitation (m3) 300,000 Projected Wastewater Generation Based on 31 year Max Precipitation (m3) Wastewater Generation (m3) 250,000 200,000 150,000 100,000 Historic Wastewater Generation LTWMF Construction and Development 50,000 Construction of Upgraded WTP 0 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020 2022 Year

Influent Water Quality Equalization pond to receive ground and surface water from different sources Conservative estimates of maximum source concentrations (weighted average) applied in estimate of combined impacted water quality Contaminants of Concern (COC) identified include: Arsenic Uranium Radium-226 Upgraded water treatment facility must reduce COC to levels as low as reasonably achievable (ALARA)

Estimated Influent Water Quality Parameter Maximum Concentration (mg/l) Parameter Maximum Concentration (mg/l) Arsenic 26.62 Sulphate 166.35 Boron 0.85 Mercury 0.0002 Calcium 96.37 Silicon 8.85 Copper 0.13 Sodium 126.88 Iron 19.22 Radium-226 (Bq/L) 10.62 Magnesium 75.53 Uranium 11.61 Chloride 50.3 Dissolved Organic Carbon (DOC) 9.99 Estimated combined impacted water quality based on weighted average using conservative estimates of maximum source concentrations

Preliminary Impacted Water Investigation Review of Potential Treatment Technologies Bench Scale Investigation of Selected Technology On-Site Pilot Testing at Welcome WMF Detailed Design of Water Treatment Plant

Treatment Technology Ferric Chloride Co Precipitation Review of Potential Treatment Alternatives apple apple apple Advantages (Pros) Simple, reliable, proven Relatively low cost/energy Solid residual (sludge) apple apple apple Disadvantages (Cons) Not effective on all COC Potentially hazardous reagents Mix tanks are of fixed size Specialized apple Excellent effluent quality Reverse apple Reliability has improved Osmosis for Impacted Water Treatment apple Reference applications verified as effective method for treatment of landfill run-off apple Membrane physical barrier to retain COC Evaporation apple Very good effluent quality apple Robust treatment method, capable of treating large range of influent concentrations apple Good track record for difficult, multiple component treatment projects Lime apple Simple, reliable Precipitation apple Relatively low cost/energy (Lime Softening) apple Solid residual (sludge) apple apple apple apple apple apple apple apple Relatively high energy and pressure requirements Potentially high volumes of liquid residual High energy requirements Degree of complexity depends on unit Concentrated brine generated (unless multiple stages used to evaporate to dryness) Potentially hazardous reagents Neutralization after treatment required Large volume of high ph residual sludge generated Over 20 individual physical, chemical and biological treatment systems were considered during review of Best Available Technologies (BAT)

Reverse Osmosis Treatment Approach Clarifier Equalization Pond Sand Filtration Reverse Osmosis Sludge Treatment Permeate Concentrate Residuals Lake Ontario Evaporator Slurry Dryer

RO Module for High Dissolved Solids Content Spacer Tube (ST) membrane and module designed to handle high dissolved solids applications; less susceptible to fouling compared to conventional RO modules ST concept, open channel design minimizes colloidal and particulate fouling Cross flow configuration and high recycle rate continuously scours membrane elements Conventional Spiral Wound Membrane Spacer Tube (ST) Membrane for High Dissolved Solids

RO ST Module for High Dissolved Solids Content Influent Concentrate Permeate

Bench Scale Study RO Treatment Performed bench testing on RO Disc Tube (DT) membrane and cell (bench scale version of ST membrane & module) on impacted water Obtained high water recovery where permeate contained 80 to 98% of sample volume Consistent rejection of COC: Arsenic >85% Uranium >99% Radium 226 >75% Recommended proceeding to on-site pilot testing to evaluate ST module performance to treat impacted water

Reverse Osmosis Bench Scale Apparatus Reverse Osmosis Disc Tube (DT) Cell

Bench Scale Study RO Treatment INFLUENT PERMEATE REJECT Jars containing stream samples from bench test with RO Disc Tube cell (from left to right): raw impacted water (influent), RO permeate, and RO concentrate (reject).

Pilot Testing Experimental Design Design of experiment (DoE) crossed 3-way mixed unbalanced model, having 9 runs with 3 repeats, to evaluate influence of main effects on measured responses. Factors evaluated: Percent Recovery Pre-treatment TDS Spike Measured responses: Operating Time Average Specific Flux Rejection of COC

Port Hope Pilot Study Design of Experiment Design Matrix Factors & Levels Tested Run # Percent Recovery Pre-treatment TDS Spike 1 85 No No 2 80 No No 3 80 No No 4 80 No Yes 5 80 Yes No 6 85 Yes No 7 85 No Yes 8 80 No No 9 75 No No Applied Stat-Ease Inc. Design Expert Version 8 software for design of experiment statistical analysis. TDS Spike refers to injecting collected concentrate from the RO unit previous runs into the influent of the first RO module. Concentrate was added to increase the electrical conductivity in the range of 1000 to 1200 us/cm. No TDS Spike means the electrical conductivity was not altered.

On-Site Pilot Testing PILOT TRAILER

On-Site Pilot Testing On-site pilot testing performed for 3 consecutive months in a metal sea container; container footprint 2.4 m by 12 m Dedicated submersible pump supplied impacted water from lagoon to pilot unit Pilot unit included: conventional pre-treatment equipment and Rochem RO-510 PT2 pilot unit containing 3 of ST RO modules Pilot data required for design of full scale facility: RO membrane flux optimization RO membrane cleaning regimes RO concentrate

Port Hope Pilot Treatment System

Port Hope Pilot Study Design of Experiment Significance of Main Effects Measured Response Main Effects Significant Operating Time Percent Recovery Yes Pre-treatment TDS Spike Average Specific Flux Percent Recovery No Pre-treatment TDS Spike Uranium Rejection Percent Recovery No Pre-treatment TDS Spike Radium-226 Rejection Percent Recovery No Pre-treatment TDS Spike Arsenic Rejection Percent Recovery No Pre-treatment TDS Spike Applied Stat-Ease Inc. Design Expert Version 8 software to perform ANOVA. First order interactions and higher included in error term. Significance based on Null Hypothesis test; F-distribution value at 5% probability level. Yes No No No No No No No No No

Graph of Operating Time Versus Percent Recovery 180 Opera/ng Time, hours 160 140 120 100 80 60 40 20 0 75 80 Percent Recovery 85 No Pre Treatment Pre Treatment

Graph of Percent Rejection Versus Contaminants of Concern 75% Recovery, No Pre Treatment Percent Rejec/on 100 80 60 40 20 0 80% Recovery, No Pre Treatment 85% Recovery, No Pre Treatment 80% Recovery, Pre Treatment 85% Recovery, Pre Treatment U Ra 226 As Contaminants of Concern

On-Site Pilot Testing Conclusions Determined from DoE, over range tested, that: operating time is affected by percent recovery and pretreatment average specific flux and COC rejection not affected by percent recovery, pre-treatment and TDS spike Deduced that system drift from set point will not significantly impact final effluent quality; built-in safety factor Verified in the RO ST module suitable for the application Obtained operating data required for sizing full scale plant

Floor Plan: CRA Plant Design

Floor Plan: Clarifier

Floor Plan: Sand Filters

Floor Plan: Rochem RO Units

Summary Upgraded impacted water treatment facility mandated by Canadian Nuclear Safety Commission for execution of Port Hope Project Reviewed Best Available Technologies; resulted in selection of a combination of ferric chloride precipitation and ST RO technology Optimized ferric chloride process and demonstrated removal of COC during Bench Scale Testing of ST RO system Validated effectiveness of ST RO membranes during Pilot Testing Acquired operating data in 3 month pilot trial; data utilized in design of full scale RO treatment facility

Acknowledgements CRA would like to thank AECL and PWGSC for permission to present information. As well, to the RPIC for this forum to present study.