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Total Coliform Rule (TCR) Sampling Procedures
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The purpose of these slides is to demonstrate recommended sampling techniques. This presentation includes: supplies needed supplies needed sample tap selection sample tap selection collection; and collection; and shipping. shipping. Total Coliform Rule Sampling
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We know and recognize that there are numerous techniques and methods for collecting drinking water samples. The idea of this presentation is to demonstrate the general method used while providing some helpful suggestions for sample collection, whether you are an owner, operator, or trainee. This presentation is in no way to be considered a substitute for the federal Safe Drinking Water Act and amendments This presentation is in no way to be considered a substitute for the federal Safe Drinking Water Act and amendments Total Coliform Rule Sampling
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What is the Total Coliform Rule (TCR)? The Total Coliform Rule, or TCR, is a rule established by the Safe Drinking Water Act (SDWA) with sample requirements primarily based on the presence or absence of total coliform bacteria rather than on the number of coliforms detected in the samples.
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What is the Total Coliform Rule (TCR)? The TCR, exists to protect public health by monitoring for fecal and other disease causing pathogens in drinking water. Each month Public Water Systems must collect a designated number of total coliform samples.
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What is the Total Coliform Rule (TCR)? By referencing the following charts, public water systems, by population size served, can locate their required number of samples and their frequency as required by the SDWA.
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Minimum Number of Routine Bacteriological Samples Required Type of System Population Served Minimum # of Routine Samples Ground Water (GW) 25 – 1,000 1 sample per month or quarter 1,001 – 2,500 2 samples per month or quarter 2,501 – 3,300 3 samples per month or quarter
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Minimum Number of Routine Bacteriological Samples Required Type of System Population Served Minimum # of Routine Samples Surface Water (SW) or Ground Water Under the Direct Influence of Surface Water (GWUDI) 25 – 1,000 1 sample per month or quarter 1,001 – 2,500 2 samples per month or quarter 2,501 – 3,300 3 samples per month or quarter
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What is the Total Coliform Rule (TCR)? Compliance with the TCR is based on the presence or absence of total coliform bacteria. If all routine samples tested negative (absent) for the presence of total coliforms, no additional testing is required for that monitoring period. Whether you sample monthly, quarterly, or annually.
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What is the Total Coliform Rule (TCR)? However, the rule requires that total coliform positive samples (presence) be further tested for fecal coliform or Escherichia Coli (E. Coli) and that a set of three repeat samples be collected for each total coliform positive sample.
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What is the Total Coliform Rule (TCR)? Repeat samples must be collected within 24 hours after the Water system officials are notified of the routine positive coliform result. Furthermore, if coliforms were detected, the water system will be required to collect a minimum of five (5) additional routine samples the following month. Population Served # of Repeat Samples required per Positive Routine Sample 25 – 1,000 4 1,001 – 2,500 3 2,501 – 3,300 3
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What is the Total Coliform Rule (TCR)? It is important to note that, initially, each water system must have an approved sampling plan that lists the frequencies and locations of samples to be collected. This plan may be reviewed, revised, or modified by your State or tribal drinking water program office.
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As an example of a compliance requirement for public water systems serving under 1000 population, only one (1) sample per month may be positive for total coliform. Only one (1) sample per month may be positive for total coliform. What is the Total Coliform Rule (TCR)?
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If a system exceeds this maximum contaminant level, or MCL, it must let the water consumers know through requirements established in another federal rule called the public notification rule. If this MCL is exceeded: The Public MUST BE NOTIFIED. What is the Total Coliform Rule (TCR)?
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State Guidelines – Rules – Sample Requirements Be sure to check with your state or tribal drinking water program office for additional guidelines, rules and/or sample requirements since they may be more stringent than those required by the federal Safe Drinking Water Act.
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TCR Sampling Supplies Before you begin sampling, it is important to have all of your supplies on hand. Here is a list of the suggested supplies you may need:
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Cooler for shipping and storage of your sample while in transit between collection point and lab. TCR Sampling Supplies
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Bagged Ice for your shipping cooler. TCR Sampling Supplies
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PVC or unsupported Neoprene gloves which are necessary to keep your hands safe from sample container preservative chemicals. TCR Sampling Supplies
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Sample Container TCR Sampling Supplies
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Lab slips, labels, and markers for sample container identification TCR Sampling Supplies
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Additional Recommended Items are: Paper towels for drying off the outside of your sample container after sampling. TCR Sampling Supplies
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Plastic storage baggies for ice and sample container TCR Sampling Supplies
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Sample preparation instructions Although different sizes and types of sampling containers may be used for collecting coliform samples, most laboratories supply 125mL sterilized, plastic bottles. A few laboratories may furnish single service, sterilized glass bottles. Although different sizes and types of sampling containers may be used for collecting coliform samples, most laboratories supply 125mL sterilized, plastic bottles. A few laboratories may furnish single service, sterilized glass bottles.
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As a general rule, proper washing of hands is highly recommended for the sample collector. Sample preparation instructions
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Also, food, drink, and even 2nd hand cigarette smoke should never come into contact with the sample or its containers. These foreign objects have been suspected of causing false results in samples, so be sure to practice good clean sample collection procedures. Sample preparation instructions
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It is recommended that you not sample with any containers that appear to have been tampered with since this may cause an undesirable sample result. Sample preparation instructions
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Sampling Instructions The laboratory that supplies the sampling containers may provide instruction with the kit for the type of monitoring being performed. Be sure to refer to those instructions when provided.
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Sampling Procedures Important Notice Follow the laboratory instructions if provided. If no instructions are provided – the following are general sampling procedures. If no instructions are provided – the following are general sampling procedures.
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Assemble all of the sampling supplies before beginning. Your sample bottle may have Sodium thiosulfate, a small white tablet or powder in the sample container, which is used for chlorinated waters (such as those found in most distribution systems). Handle the containers carefully as they are sterilized. Do not rinse out or dispose of any liquids, powders or tablets inside the containers. Assemble all of the sampling supplies before beginning. Your sample bottle may have Sodium thiosulfate, a small white tablet or powder in the sample container, which is used for chlorinated waters (such as those found in most distribution systems). Handle the containers carefully as they are sterilized. Do not rinse out or dispose of any liquids, powders or tablets inside the containers. Sampling Procedures
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Select an approved sampling location if any have been designated. Normally, the sampling location (s) is specified in the approved sampling plan as reviewed by your state drinking water program. Each representative sampling location is usually located in the distribution system and is usually considered accessible during the day. Sampling Procedures
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Examples include hospitals, city buildings, pump stations, restaurants, and dedicated sampling stations. Sampling sites specified in the sampling plan should be selected carefully throughout the distribution system to represent the varying conditions that occur throughout your system or plumbing. Sampling Procedures
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It is especially important to identify and include in the sampling site selection those areas that may adversely affect the microbiological quality of the water. These include high use areas such as taps serving wait staff servicing stations, bathroom taps where consumers make contact with the water, and taps in food preparation areas. Sampling Procedures
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Sampling sites should also consider cross connections, varying population densities, low-pressure zones, sites of deteriorating water lines, shared connections, dead ends, areas of low-velocity water movement, and other trouble spots in the distribution system. Sampling sites should also consider cross connections, varying population densities, low-pressure zones, sites of deteriorating water lines, shared connections, dead ends, areas of low-velocity water movement, and other trouble spots in the distribution system. Sampling Procedures
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Faucets and specially-installed sampling taps are the two most common types of sampling sites. If faucets are to be used, each faucet should be examined carefully to ensure its suitability. Poor faucet design or placement may contribute to invalid sample results or fail to identify problems within your water system. Faucets and specially-installed sampling taps are the two most common types of sampling sites. If faucets are to be used, each faucet should be examined carefully to ensure its suitability. Poor faucet design or placement may contribute to invalid sample results or fail to identify problems within your water system. Sampling Procedures
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Some examples of undesirable faucet conditions are: Swivel-type faucets that have a single valve for hot and cold water. Faucets that have leaky packing material around the stem. Faucets that supply areas where bacterial contamination is likely, such as janitorial or commercial sinks. Faucets close to or below ground level. Faucets that point upward (such as drinking fountains). Faucets that have threads on the inside of their spouts. Faucets that have aerators. (If such faucets are to be used, the aerators must be removed before a sample is collected.) Sampling Procedures
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To avoid the problems inherent with faucets, some water suppliers collect water samples for coliform analysis from special taps connected directly to distribution piping. These special taps can be simply a faucet at the end of a riser pipe connected to the distribution line or a more sophisticated manufactured sampling station device. To avoid the problems inherent with faucets, some water suppliers collect water samples for coliform analysis from special taps connected directly to distribution piping. These special taps can be simply a faucet at the end of a riser pipe connected to the distribution line or a more sophisticated manufactured sampling station device. Sampling Procedures
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If possible, remove any aerator, strainer, or hose that is present, as any of these many harbor bacteria and cause a false coliform positive sample result. Sampling Procedures
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OPTIONAL STEPS: OPTIONAL STEPS: Some sampling practices involve spraying the tap with a chlorine solution, or even flaming the tap. (This step is optional since many people believe this practice does not kill attached bacteria and is not necessary if the sampling tap is selected carefully.) Keep in mind that the average consumer will not perform such practices and could be argued that doing so would not properly represent the water quality at the point where the consumer will use it. Some sampling practices involve spraying the tap with a chlorine solution, or even flaming the tap. (This step is optional since many people believe this practice does not kill attached bacteria and is not necessary if the sampling tap is selected carefully.) Keep in mind that the average consumer will not perform such practices and could be argued that doing so would not properly represent the water quality at the point where the consumer will use it. Sampling Procedures
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Turn on the cold water and run the water to flush the tap. This typically takes 2-3 minutes. Then reduce the flow so that the stream is no greater than ¼ inch in diameter, or the width of a pencil. Check for steady flow. Sampling Procedures
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While the water is running, fill out the labels, tags, and laboratory forms. Apply the labels to the containers. Do not change the water flow once the sampling has started as that could dislodge microbial growth. Test for both the chlorine and the pH of the water and place the results on your lab slip. Sampling Procedures
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Remove the bottle cap. Be careful not to contaminate the sample by touching the inside of the cap or the inside of the sample container with your fingers. Sampling Procedures
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Then position the bottle under the water flow. Hold the bottle in one hand and the cap in the other. Do not lay the cap down or put it in your pocket! Water dripping from your hands may also cause contamination of the sample so extra care should be taken when collecting this sample. Sampling Procedures
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Fill the bottle to the shoulder or to about ¼ inch from the top. Many bottles have a 100ml fill line. Sampling Procedures
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The sample container should be tightly capped. Blot the sample container with a paper towel to dry it off. The sample container should be tightly capped. Blot the sample container with a paper towel to dry it off. Sampling Procedures
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Since Ice is sometimes recommended for use in shipping, it is recommended that it be bagged separately to eliminate any contamination of the sample. Turn the tap off. Replace the aerator, strainer, or hose.
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Check that the information on the label is correct (or check the laboratory form and attach it to the bottle with a rubber band). Complete any additional laboratory forms that came with the sample bottle, including chain-of- custody form (if necessary). Sampling Procedures
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The samples must reach the laboratory and the analysis must begin within 30 hours of collection. It is recommended that all samples be refrigerated or cooled to 4 degrees to 10 degrees Celsius (39 degrees to 50 degrees Fahrenheit). If the laboratory is nearby, refrigerate with ice packs, and deliver the samples there directly. If not send the samples overnight by US mail or by an overnight courier. Sampling Procedures IMPORTANT:
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Taping of the chest prior to shipping is also recommended since the container could be mistakenly opened during shipment. Also be sure to tape the sample forms and any other sample documentation either inside or the outside of the lid. Sampling Procedures RECOMMENDED:
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If the laboratory has any additional shipping recommendations or requirements, they should be read and followed closely. Sampling Procedures
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If you have any additional questions, please contact your state or tribal drinking water program office for assistance. Following the proper drinking water sample collection procedures can lead to peace of mind, knowing that the test results truly represent the quality of water your customers are drinking. After all, isn’t our goal to ensure... Following the proper drinking water sample collection procedures can lead to peace of mind, knowing that the test results truly represent the quality of water your customers are drinking. After all, isn’t our goal to ensure... Sampling Procedures
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Total Coliform Rule (TCR) Sampling “Water Safe to Drink”
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