Zequanox Demonstration Trials at DeCew II Generating Station at Ontario Power Generation to Control Dreissenid Mussels

Transcription

1 Zequanox Demonstration Trials at DeCew II Generating Station at Ontario Power Generation to Control Dreissenid Mussels Tony Van Oostrom, Ontario Power Generation Bridget Gruber, Carolyn Link, and Sarahann Rackl, Marrone Bio Innovations Kelly Murray, ASI Group

2 Overview of the Presentation 1.0 Background to Ontario Power Generation 2.0 Current Treatment Approach - Sodium Hypochlorite 3.0 Pseudomonas fluorescens Discovery 4.0 What did OPG Do 5.0 Regulatory Regime 6.0 Project Objectives 7.0 Methods 8.0 Results 2012 Trial at DeCew II GS 9.0 Treatment Dilution 10.0 Water quality and eco-toxicology data 11.0 Next Steps

3 OPG Was Established in 1999 April 1, 1999 split into five entities

4 19,051 MW generating capacity 2012 Energy produced: 83.7 TWh 65 hydro, 2 nuclear, 5 thermal 2 leased nuclear stations Generates about 60% of Ontario s electricity Full-time Employees 10,840 Major projects Niagara Tunnel Atikokan biomass conversion Lower Mattagami OPG at a Glance* As of Dec. 31, 2012

5 2.0 Current Treatment Approach Reactive Form of Periodic Treatment (2003 to present) 24 hr/day at target dose of 0.65 ppm for a 10 days minimum Total Residual Chlorine levels maintained in ppm range Warm water treatment (>15 C) for a quicker kill Monitor effectiveness biobox bioassay

6 2.0 Current Treatment Approach Where do you go from here? NPG had reduced usage of sodium hypochlorite by over 80% since 1990 Minimal ability to reduce sodium hypochlorite usage & maintain effectiveness Looking for an approach that is environmentally friendly, and effective Want to be able to use the same infrastructure reduce cost to change Would like to reduce hazards to staff from exposure to product

7 3.0 Pseudomonas fluorescens Discovery Zequanox is derived from soil microbe (Pseudomonas fluorescens) discovered by NYSM Composed of 100% dead cells Controls mussels in all life stages Perceived as food source destroys the mussel s digestive system Highly selective toward zebra/quagga mussels Effective in a broad range of water conditions and temperatures Noncorrosive and Nonvolatile Zebra Mussel Workshop, Saskatoon

8 3.0 Pseudomonas fluorescens Discovery Mode of Action Dead Pseudomonas fluorescens cells contain compounds that destroy epithelial cells in the mussel s digestive system, cause hemorrhaging and death Must be ingested to be effective Death can occur within days to weeks Mussels perceive Zequanox as food and readily feed Unlike with many chemicals, mussels do not close shells in reaction to the presence of Zequanox Digestive gland before ingesting Zequanox: Healthy epithelial cells (arrows) surround the tubules in the digestive gland Zequanox is highly selective to zebra and quagga mussels (Dreissena species) Following ingestion of Zequanox: Blood cells are abundant inside the hemorrhaging digestive gland Zebra Mussel Workshop, Saskatoon

9 4.0 What did OPG Do? Tailrace DeCew 2 GS Marrone Bio Innovations (MBI) entered initial agreements with New York State Museum (NYSM) to commercialize Pseudomonas fluorescens strain CL 145A in 2008 After concept endorsement by Senior Management, NPG approached the NYSM and MBI about doing a trial in Canada Accepted. After consultation with the MOE and the Pest Management Regulatory Authority, plans put in place to initiate a trial

10 4.0 What did OPG Do? Percent Full Plant Treatment Mortality

11 5.0 Regulatory Regime Research Authorization From the Pest Management Regulatory Authority in Ottawa Approx 6-8 months, comes with conditions Allows importation into Canada & trial execution Environmental Compliance Approval From Ontario Ministry of Environment Approx 1-2 months Detailed conditions including discharge objectives

12 6.0 Project Objectives Background: DeCew 2 chosen as it was small to mid-size plant. 144 MW of generation Generation flow 691,000 m3/hr Service water (treated flow) 430 m3/hr used existing infrastructure for chlorine treatment

13 6.0 Project Objectives

14 6.0 Project Objectives Objectives: Testing efficacy and reliability of material produced at a commercial manufacturing scale Testing ease of use (e.g. mixing) Testing mixing onsite without the need for a staging location Testing addition of an antifoaming agent to prevent foam formation in the tail race Concentration optimization

15 7.0 Methods Trial completed within 12 hours on August 1, 2012 and on September 6, 2012 Used existing treatment infrastructure Used Quadro ZC1 mixing and totes to insure proper mixing on site Used calibration columns on pumps as well as turbidity checks to verify concentration

16 7.0 Methods Full Scale Treatment Bypass pipe was designed as another means of evaluating actual trial performance through a bioassay During Treatment all cooling water flow is directed through the bypass pipe to more closely simulate a real world environment Includes a removable stainless basket seeded with several hundred adult Zebra and Quagga Mussels

17 8.0 Results August 1, 2012 Zequanox Treatment Day 7: 91% mortality Final Mortality: 94%

18 8.0 Results September 6, 2012 Zequanox Treatment

19 8.0 Results Summary Successful control of dreissenid mussels at Decew II GS in As a result, OPG DID NOT conduct a chlorine treatment in 2012 August 1, 2012 treatment: 150 mg a.i./l resulted in 94% mortality of adult mussels September 6, 2012 treatment: 100 mg a.i./l resulted in 64% mortality 80 mg a.i./l resulted in 71% mortality Bypass Pipe Mortality 97% (after both treatments) Powder formulation has been shown to have variability in results ( mg a.i./l yields 70% - 100% mortality). MBI further optimizing formulation and addressing variability Success of the treatments supports success of onsite mixing, and the ability to eliminate offsite mixing location. Successful prevention of foam formation with the use of the antifoam agent Concentration optimization: greater than 70% mortality can be achieved with concentrations as low as 80 mg a.i./l.

20 9.0 Treatment Dilution Calculated effluent concentrations: <0.123 mg a.i./l for August 1, 2012 treatment <0.061 mg a.i./l for September 6, 2012 treatment > 1000x dilution

21 10.0 Additional water quality and eco-toxicology data After 3 years of environmental monitoring and in situ nontarget tox studies, MOE reduced 2012 monitoring requirements due to de minimus risk of Zequanox No observable difference in water quality before and after treatment No impact to trout, native bivalves, or daphnia

22 10.0 Additional water quality data 2011 Water quality monitoring Upstream and downstream; before, during and after No significant difference for all parameters tested, before, during, and after treatment. Twelve Mile Creek water quality Trial Time August, 2011 Location of Collection Time of collection TOC (mg/l) BOD (mg/l) Turbidity (NTU) Temp ( C) Upstream 1 hour pre trial 2.8 < Upstream 2 hours into trial 2.9 < Upstream 4 hours into trial 2.8 < Upstream 2 hours post trial 2.8 < Downstream 1 hour pre trial Downstream 2 hours into trial 2.9 < Downstream 4 hours into trial 2.9 < Downstream 3 hours post trial 3 <

23 10.0 Additional eco-tox data Zequanox treated water pulled directly from cooling water lines: NOT toxic Daphnia magna or Rainbow trout (passed Environment Canada testing protocols for acute toxicity testing) Native freshwater mussels (Eastern elliptio) tested alongside dreissenid mussels: 0% mortality was observed after 30 days

24 11.0 Next Steps Followup and Look at Opportunities to carry out treatments at Other Niagara Facilities

25 Questions? Tony Van Oostrom, Ontario Power Generation Bridget Gruber, Carolyn Link, and Sarahann Rackl, Marrone Bio Innovations Kelly Murray, ASI Group