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James Latimer Environmental Program Specialist Drinking Water Program AK Dept. of Environmental Conservation E-mail: james.latimer@alaska.gov. Planning for and Collecting Valid and Meaningful Drinking Water Samples. 2010 Sustained Compliance Workshop Anchorage, AK Sept 23-24, 2010.
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James Latimer Environmental Program Specialist Drinking Water Program AK Dept. of Environmental Conservation E-mail: james.latimer@alaska.gov Planning for and Collecting Valid and Meaningful Drinking Water Samples 2010 Sustained Compliance WorkshopAnchorage, AKSept 23-24, 2010
Presentation Summary • Sample Planning – generalized and detailed • Collecting Samples – preparations and procedures • Sample Demonstration – total coliform & chemical • Sample Results – understanding results and following through as needed • Questions
Sample Planning • Planning Tools • Total Coliform Sample Siting Plan • Lead & Copper Sample Plan
Importance of Planning • Planning ahead can be critical to maintaining an adequate supply of safe and healthy water • To succeed, we need to know (and do): • what needs to be done • when & where to sample
A Monitoring Summary includes: What to sample for & where to sample How often to sample Date of last sample Date next sample is due Definitions and explanations DEC contact information
Other Planning Tools Quarter • Printed media • e.g., wall or desk calendar • Electronic media • e.g., email alerts
Specific Sample Plans The following sampling plans will not be covered today: • A source water monitoring plan for Long Term 2 Enhanced Surface Water Treatment Rule (LT2); or • A Stage 2 Disinfectant and Disinfection Byproducts Rule (Stage 2 DBPR) Initial Distribution System Evaluation (IDSE) sampling plan
Creating, Using, & Modifying a Total Coliform Rule (TCR) Sample Siting Plan
Total Coliform Sample Siting Plan (18 AAC 80.410) • Who is required to have one? • Applies to Community, Non Transient Non-community, & Transient Non-community public drinking water systems • What it is? • Where and when to sample • Routine sampling; and • In the event of total coliform positive result: • Within 24 hours, and the following month • Sample site selection is important • Keep a copy readily available onsite, & revise as needed
DEC TCR Sample Siting Plan* “Template” * for smaller systems, serving 1000 or less people http://dec.alaska.gov/eh/dw/publications/forms.html
What to do if a result is positive/present for total coliform bacteria or E. coli
Distribution System Schematic • Any format • E.g., engineer schematic, hand-drawn, notes on satellite image, and others • DEC Drinking Water Program staff review & approve all Total Coliform Sample Siting Plans
Lead and Copper Sampling Plan (CWS and NTNCWS) • Site selection • Based on materials evaluation (pipes and fixtures containing lead and/or copper), & use (i.e. residential vs. commercial) • Do not include sites with point-of-use or point-of-entry treatment devices for inorganics (1 exception) • What to do if not enough sites. • Names or IDs of sites should be clear and consistent • Consistent locations provide results that can be compared over time • Accessibility - changes • Activity/Inactivity (i.e. , schools) • First Draw, after 6 hours with no-flow • Newly replaced pipes or fixtures may influence results
Lead and Copper Sampling Plan Essentials • Provide an explanation for selection of sites • Provide clear and complete descriptions and names for each site, and include alternative sites • Note sample procedures • Flushing procedures • Describe how 6-hour idle flow time will be met • Note if residents will collect samples • Emphasize collection from cold water tap • Emphasize use of consumptive taps
Collecting Samples • Preparations • Supplies, Instructions, Forms • Collecting samples • Tap or site issues • Potential contamination • Container specifics • Demonstrations • Total Coliform • Volatile Organics (VOCs) • Recording & reporting data
Pre-collectionPreparations • Supplies • Sample bottles • Valid free chlorine residual powder packets • Tools & paper towels • Cooler (s) • Ice & packing materials • Disinfectant • Forms • Other items as needed • Arrangements • Lab hours • Flights • Coordinate with any relevant contractors • Courtesy reminders to home or business owners –ensure access • Payments • Other items as situation warrants
Quiz & Clues –Distribution System Free Chlorine Residual • Same Time & Location as each Total Coliform Sample • Collect prior to Total Coliform sample • Free - and check powder packet type & expiration date • There is at least one approved free chlorine residual test strip • When and where do we sample distribution chlorine residual? • Do we sample before or after total coliform sampling, and does it matter? • Is this a free or total chlorine measurement? • How about test strips?
Distribution Chlorine Residual http://dec.alaska.gov/eh/dw/publications/sample.html
Common Methods of Determining Free Chlorine Residual Follow instructions provided by the manufacturer
Total Coliform BacteriaSampling Reminders • Arrange transportation • Keep enough extra sample bottles on site • Confirm sample location on the sample siting plan • Personal and area sanitation is important • Prepare faucet (avoid sampling at drinking water fountains): • Disinfect then flush • Fill to 100+ ml - not too little • < 100ml gets rejected • Not too much • Sample bottles are brittle • Pad for shipping, and do not submit if damaged • Cool, yet not frozen • Double check forms • Limited hold time
Total Coliform Bacteria Sampling http://dec.alaska.gov/eh/dw/publications/sample.html
Non-TCR Samples Today’s Special - VOCs • Volatile Organic Compounds (VOCs) • Total Trihalomethanes (TTHM) & Haloacetic Acids (HAA5) • Lead & Copper • Inorganics • Arsenic • Fluoride • and more... • Special bottle/lid • Open septa lid prevents contamination while allowing for sample extraction at lab • Do not rinse bottle • Low tap flow • Close to tap • Bottle angled • Fill completely - no air space • Minimize overflow
VOC Sampling http://dec.alaska.gov/eh/dw/publications/sample.html
Partially Completed Forms the lab the lab
Sampling Demonstrations • West aisle • Kelly Cobbs (DEC) • East aisle • Leticia Tadina (DEC)
Reporting • Ensure that time and money are not wasted: • Recheck forms & labels for accuracy & completeness • Label on bottle • Labs are required to report results directly to DEC • PWSs are responsible to ensure that DEC receives results
Points To Ponder & To Act On • Plan & sample as far ahead as possible • Develop, revise, and keep handy TCR and Pb/Cu sample plans • Understand and use the Monitoring Summary, and use in combination with a calendar or other sample scheduling or tracking media. • Sampling begins and ends with accurately and completely filling out forms • Understand & address sample issues specific to each type of sample collected • Accurate results are very important • Water is very important • Your job is very important
Thee End! ??? Questions, comments ???