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Brazos County Health Department
April 7, 2015
IntroductionsKen Bost – BCHD Director
Amanda Garner – BCHD Lab Director
Amy Bauer – Lab Assistant
Kristen Ramseier – Lab Assistant
Jesus Rodriguez
Shelley Hobbs
Importance of Testing Your Well Just because your water is clear and
smells okay does NOT mean it’s not contaminated
Total coliform bacteria can be an indicator of more serious intestinal parasites and pathogens
E. coli and total coliform bacteria can be extremely dangerous for immunocompromised individuals
Importance of Testing Your WellCan be an indicator of an improperly
constructed or failing septic system
Increased fracking and drilling can damage your well and underground pipes
Establishes a record of water quality
Importance of Testing Your Well“There are a variety of bacteria, parasites, and viruses which can potentially cause health problems if humans ingest them in drinking water. Testing water for each of these potential pathogens (disease causing agents) would be difficult and expensive. Instead, water quality and public health workers measure coliform levels. The presence of any coliforms in drinking water suggests that there may be a pathway for pathogens and/or fecal contamination to enter the drinking water distribution system (pipes, storage facilities, etc.).”
- Water: Total Coliform Rulehttp://water.epa.gov/lawsregs/rulesregs/sdwa/tcr/basicinformation.cfm
Total Coliform bacteria and E. coli Total coliform bacteria originate in natural habitats
such as soil, water, and vegetation, and in the intestines of warm-blooded organisms
E. coli is commonly found in the intestines of warm-blooded organisms and is an indicator of fecal matter
How can this bacteria affect humans? Cause gastrointestinal problems
Serious for immunocompromised individuals
E. coli may be a pathogen – can be lethal
Indicator of more serious pathogens that can cause:
Typhoid
Dysentery
Cholera
Some types of gastroenteritis
How does bacteria enter a well?Runoff from woodlands, pastures, and
feedlots
Septic tanks and sewage plants
Animals including wild fowl
Backflow from a contaminated source
Old/broken well equipment and pipes
While repairing or installing a well
How does bacteria enter a well? Except for very rare instances, the underground water
in this area is not contaminated. Any contamination found in well water is almost certain to have come from outside sources.
A new well is likely to be contaminated until it has been properly treated.
Drinking water standards No regulated standards for private wells
The Texas Commission on Environmental Quality (TCEQ) enforces standards for public water systems
Under the Safe Drinking Water Act (SDWA), the EPA sets legal limits on the levels of certain contaminants in drinking water. The legal limits reflect both the level that protects human health and the level that water systems can achieve using the best available technology.
The EPA requires public water contain NO total coliform per 100 ml of drinking water.
Water Testing Must be an accredited water testing laboratory
BCHD laboratory is certified by TCEQ
Also certified by The Nelac Institute (TNI)
Routine audits every two years
Proficiency testing twice a year
Water Testing Use the Colilert test to detect total coliforms and E. coli
in water
Test takes 24 hours to provide a final, negative result
If a sample is positive it can be resulted before 24 hours
Samples set up twice a day at 1 pm and 3 pm
Each sample is provided a unique identifier number
Each sample is tested for chlorine level
Not required to be on ice, but recommended
Collecting Samples for Testing DO NOT RINSE OUT THE BOTTLE!
Use a faucet as close to the well as possible. If an inside faucet is used, remove the aerator before collection.
Wash and dry the exterior of the faucet to prevent external contamination of the sample.
Turn on the faucet full force for 2-3 minutes to flush out anything which might be in the immediate pipes or the faucet itself, then turn the flow down to a slow stream.
Carefully remove the cap, making sure that nothing touches the inside of the cap or the bottle.
Without creating a splash, fill the bottle to the 100 ml mark.
Make sure each bottle is correctly identified.
Samples must be received within 24 hours of the time of collection.
Collecting Samples for Testing
Sample Rejection Water samples may be rejected for testing for a variety
of reasons including:
The sample is too old (over 24 hours)
Insufficient volume of water
Excessive chlorine present
Heavy silt/turbidity present
In most cases you will be notified that we are unable to test your sample when you are dropping it off.
In some cases we may call you after you’ve left to inform you we are unable to test your sample.
Must retake and resubmit a new sample.
Resulting Water Samples When total coliforms break down the nutrient indicator,
the sample turns yellow
When E. coli metabolizes the nutrient indicator, the sample also fluoresces under a black light
Samples only have to be as yellow as the comparator bottle
Disinfecting Your Well Turn off pump and drain cistern/pressure tank.
Open access hole into casing. If your well has a self-priming surface mounted pump, this procedure may not be necessary.
Place a funnel into the access hole and pour I gallon of household bleach per 100 feet of depth into the well.
Turn the well pump on and off several times to "bump" the well and mix the bleach and water.
Connect a section of garden hose to the faucet at the pressure tank ( or the nearest faucet if the pressure tank does not have one) and place the other end into the funnel. Turn on the pump and the faucet and allow the water to circulate from the well to the tank and back to the well for 15-30 minutes.
Disinfecting Your Well Close the faucet and the access hole to the well.
Go to all water faucets in the entire system being served by the well and open them until you can smell the bleach. Start with the faucet nearest the well and work away from it.
Make sure that every outlet is flushed with the treated water. Flush the toilets, run the showers, washing machine, dish washer, ice-maker, outside faucets, etc.
If there are any dead end lines, they must be opened and flushed as well.
If the system is quite extensive, you may need to add more bleach to the well to ensure adequate treatment of the system.
ALLOW THE SYSTEM TO STAND AT LEAST OVERNIGHT WITH THE BLEACH IN THE LINES.
Remove any filters-or aerator screens from the fixtures and flush the system with fresh water until all debris and discolored water is removed and the bleach can no longer be smelled.
Replace the filters and screens and use the water normally for a few days, then resample.
Disinfecting Your Well
In some cases, this procedure may need to be repeated two or even three times to clear up a severe contamination problem.
This disinfection procedure will work only if the system is in a good state of repair. Leaky pipes, cracked casing or similar problems will allow immediate recontamination.
The system will need to be disinfected any time there is work on the pipes or pump.
Disinfecting Your Well
Additional Resources Brazos County Health Department
http://www.brazoshealth.org
EPA http://water.epa.gov/drink/info/well/
TCEQ http://www.tceq.state.tx.us/
Texas Well Owner Network http://twon.tamu.edu/
Texas Department of Licensing and Regulation http://www.tdlr.texas.gov/wwd/wwd.htm
Additional Water Testing Labs Aqua-Tech Laboratories
635 Phil Gramm Blvd. Bryan, TX 77807
(979) 778-3707
Mega Lab 2700 Finfeather Rd, Bryan, TX 77801
(979) 779-7680
TAMU Lab 345 Heep Center, College Station, TX 77843
(979) 845-4816
Questions?