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Zebra Mussel Abatement. Anne Lucietto Fermi National Accelerator Laboratory FESS/Ops – Engineering April 18, 2007 2007 DOE/Contractor Fire Protection Workshop. Issues. The Zebra Mussel Methods of Control Control Considerations Project Steps. The Zebra Mussel. Methods of Control.
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Zebra Mussel Abatement Anne Lucietto Fermi National Accelerator Laboratory FESS/Ops – Engineering April 18, 2007 2007 DOE/Contractor Fire Protection Workshop
Issues • The Zebra Mussel • Methods of Control • Control Considerations • Project Steps
Methods of Control • Chemical molluscicides: Oxidizing (chlorine, chlorine dioxide) and Non-oxidizing • Manual removal (pigging, high pressure wash) • Dewatering / Desiccation (freezing, heated air) • Thermal (steam injection, hot water >32°C) • Acoustical vibration • Electrical current • Filters, Screens • Coatings: Toxic (copper, zinc) and Non-toxic (silicone-based) • Toxic constructed piping (copper, brass, galvanized metals) • Carbon dioxideinjection • Ultraviolet light • Anoxia / Hypoxia • Flushing
Considerations Made by the Committee • Configuration of ICW System and Ponds • Location of Zebra Mussels found • Materials of system/age of system • History of repairs • Flows on a “normal” basis
Other Considerations • There is no effective means of controlling zebra mussels. Prevention of further spread is key to minimizing its impacts. • Zebra mussels are physically removed from coated surfaces, such as water intake pipes, as needed.
Steps in Project • Determine BEST method of abatement • Align System for Introduction Phase • Inject EVAC into system at Casey’s Pond • Monitor System for flow and concentration • Monitor System for signs of mussel separation • Begin/Continue Flush until cleared of shells
Monitor System for Flow and Concentration Lessons Learned Realignment needed to achieve accurate dosing in: • Main Injector • Main Ring/Tev • Area Near Cross Gallery
3 new hydrant flows introduced to induce accurate flow and dosing 60% increase in testing originally planned – to provide more data to benefit future treatment EVAC concentrations following this phase lower than anticipated (by 25%) Separation of shells progressing slower than anticipated due to lower water temps Changes Resulting in Successful Completion of Introduction Phase
Lessons Learned • Flow is not even throughout system and changes to original procedure were necessary. • When completed they resulted in even chemical distribution. • Extra care needed on out flows from FCC and Industrial Buildings to eliminate/reduce fish kill in Bull Rush Pond and Proton Ditch. • When exercised no fish kill was observed.
Pre-Flush department briefings 24/7 flushing by shop to minimize clogging Due to careful pre-planning and constant flushing no clogging occurred. Begin/Continue Flush Until Cleared of Shells
Results of Flush 3,000# removed from pipes 10,200# removed from intake Heavy concentrations in: • Fixed Target • Meson Central Cryo/LLRW • TPL • PB6 & PB7 • Labs A-G • New Muon • CHL & IB1A • Reflecting Pond • Cross Gallery
Results of Flush (con’t) • Smaller Shell Sizes at New Muon – somewhat uniform first flush • Very large sizes found near Wilson Hall (5-6 years old) • General mix in size throughout site
Moving Forward • Twice a year treatment will keep all at bay and further issues with shells will not be an issue……will be transparent to user. • Other options are being investigated. • Overall in the first chemical treatment we were successful even though we had some problems. • Subsequent treatments were completely successful due to adjustments made from lessons learned. • Watching for new/better technologies for zebra mussel abatement.