TOTAL COLIFORM RULE COMPLIANCE A Guide for Public Water Systems

Transcription

1 TOTAL COLIFORM RULE COMPLIANCE A Guide for Public Water Systems Colorado Department of Public Health and Environment Water Quality Control Division Colorado Safe Drinking Water Program December 2013

2 TOTAL COLIFORM RULE COMPLIANCE Table of Contents INTRODUCTION... 3 APPLICABILITY AND DEFINITIONS... 3 OVERVIEW OF THE TOTAL COLIFORM RULE (TCR) AND THE GROUNDWATER RULE (GWR) REQUIREMENTS... 3 MONITORING PLANS... 5 SAMPLE LOCATION... 7 BEST SAMPLING PRACTICES... 8 POSITIVE TC INVESTIGATION... 8 SAMPLE INVALIDATION REPEAT SAMPLING SPECIAL PURPOSE SAMPLES PRIMARY REPORTING REQUIREMENTS REFERENCES Appendix A. Total Coliform Monitoring Frequency for Community Water Systems (CWSs) Appendix B. Best Sampling Practices Appendix C. TCR Positive Investigation Report Template Appendix D. TCR Positive Sample Invalidation Request Form Appendix E. TCR Customer Requested Special Purpose Bacteriological Sample Verification Page 2

3 TOTAL COLIFORM RULE COMPLIANCE TOTAL COLIFORM RULE COMPLIANCE A Guide for Public Water Systems INTRODUCTION The purpose of the Total Coliform Rule (TCR) is to monitor for the presence of microbes, specifically coliform bacteria, and to determine whether the drinking water in the distribution system of a public water system (PWS) is potentially contaminated with pathogens. Ingestion of pathogens in drinking water may result in gastroenteritis, hepatitis, myocarditis, paralysis, acute hemorrhagic conjunctivitis, meningitis, and/or other negative health impacts. Drinking water contamination can occur either before or after treatment. Treated water may be contaminated through improperly treated or maintained facilities or in the distribution system (e.g., cross connection, aging infrastructure, leaking septic tanks, etc.). This document serves as guidance to assist PWSs in complying with the TCR requirements, as identified in Article 5 of the Colorado Primary Drinking Water Regulations 1 (CPDWR). APPLICABILITY AND DEFINITIONS This document can be used by all PWSs, including community (CWS), non-transient noncommunity (NTNC), and transient non-community (TNC) water systems. This guidance was prepared based upon the current requirements in the state statute and regulations. EPA promulgated a new federal total coliform rule in February 2013, which EPA calls the Revised Total Coliform Rule ( RTCR ). The Safe Drinking Water Program (Program) will initiate the rulemaking process in early 2014, including the stakeholder process. The purpose of this document is to provide guidance to the regulated community during the interim period while the Program develops and implements the state s version of RTCR. Must and Shall mean the criterion is a requirement per the CPDWR. Must is considered the equivalent of Shall. Should means the criteria is best practice but is not a regulatory requirement. OVERVIEW OF THE TOTAL COLIFORM RULE (TCR) AND THE GROUNDWATER RULE (GWR) REQUIREMENTS What is the Groundwater Rule (GWR) and how does it relate to the TCR? The purpose of the GWR 1,2 is to provide for increased protection against microbial pathogens in PWSs that use Page 3

4 TOTAL COLIFORM RULE COMPLIANCE ground water sources. The GWR specifically identifies and targets ground water (GW) systems that may be susceptible to fecal contamination and requires a corrective action for GW systems with confirmed fecal contamination and/or significant deficiencies. The GWR builds upon the TCR by addressing the risk associated with consuming water from a fecallycontaminated GW source. A GW system must conduct triggered source water monitoring when the PWS is notified of a positive total coliform (TC) sample in the distribution system. This monitoring allows the system to determine whether or not the positive TC sample was due to well contamination or a distribution system-related issue. What are the different types of TCR and GWR compliance samples? Compliance sample types are as follows: o TCR compliance samples:tcr compliance samples are collected in the distribution system. There are three types of TCR compliance samples: Routine: The number of required samples is based on the population served (Appendix A). NOTE: Pursuant to Article 5.1.1(e)(5), a noncommunity water system that is not open year round must monitor for total coliforms at least 10 days prior to opening for the season. These pre-opening samples should be labeled as routine. Repeat: These are samples that are collected in response to any routine TC positive sample. Increased Routine: These are samples that are required the month following a routine total coliform positive sample. If a PWS collects fewer than five routine bacteriological samples per month and has at least one TC positive sample, and the Department does not invalidate the sample(s), the PWS must collect at least five routine samples during the next month the PWS provides water to the public (Article 5.1.2(f)). o GWR Compliance Samples: GWR samples are collected at all groundwater source(s) prior to any treatment (i.e., raw water). There are two types of GWR samples: Triggered source water monitoring: These samples are collected from the source water in response to a routine distribution TC positive sample that was collected as part of the TCR. Source water assessment monitoring: These are raw water samples collected from the source water in response to a corrective action, hydrogeologic sensitivity assessment, or any assigned Departmentrequired monitoring. Do all PWSs have to collect TC samples? All CWSs must collect TC samples every month, regardless of the type of source water (Appendix A). Non-community systems (e.g., TNC and Page 4

5 TOTAL COLIFORM RULE COMPLIANCE NTNC) must collect samples at the listed frequency for the following situations (Article 5.1(e)(1)-(4): o A non-community water system using only GW and serving less than or equal to 1,000 people must monitor TC samples in each calendar quarter that the system provides water to the public. o A non-community water system using only GW and serving more than 1,000 people must monitor at the same frequency as a like-sized CWS. o A non-community water system using ground water under the direct influence of surface water (GWUDI) must monitor at the same frequency as a like-sized CWS. o A non-community water system using surface water (SW), in total or in part, must monitor at the same frequency as a like-sized community water system. How does a PWS determine the number of routine distribution coliform samples that must be collected each month? CWSs monitor for TC at a frequency based on the population served by the system (Appendix A). Please reference the question above for the sampling requirements for non-community systems. If a system does not chlorinate, what is their monitoring frequency? A waivered system, regardless of its system classification, must monitor at the same frequency as a like-sized community water system. Existing discovered systems, without approved disinfection that is installed and properly operating, will likely be required to monitor for TC twice per month (i.e., every two weeks). The number of required TC samples will be based on the population served (Appendix A). MONITORING PLANS Do all routine TC sample sites need to be identified in the Monitoring Plan? Yes. PWSs must collect TC samples at sites that are representative of water throughout the distribution system according to a written sample-siting plan (Article (a)). Representative samples that accurately reflect the quality of the finished drinking water are crucial because if total coliforms are detected in the water supply, they may not be found uniformly throughout the distribution system. Depending on a PWS s distribution system configuration, one way to meet the representativeness requirement is to rotate the sample collection locations throughout the distribution system. For systems that only consist of a well and a single building (e.g., an office building or motel), the PWS should rotate samples at various sinks/taps located throughout the building (e.g., women s bathroom, kitchen sink, etc). Sample rotation allows for coverage of the distribution system without increasing the need for additional samples. How must samples collected based on customer requests or customer complaints be incorporated in the Monitoring Plan? Many PWSs collect TC samples as part of their Page 5

6 TOTAL COLIFORM RULE COMPLIANCE customer service. The Department encourages such practices. The Monitoring Plan can simply describe the PWS s approach to collecting such samples. The Department recognizes that the exact sample location will vary and cannot be predicted for these cases. What are the reporting requirements for TC samples that are representative of water throughout the distribution system but are not identified in the Monitoring Plan? All TC samples that are representative of water quality in the distribution system must be submitted to the Department and will be used to determine compliance (Article 5.1.1(b)). Please refer to the Special Purpose section of this document for the definition of special purpose TC samples. It is acceptable to have more than the minimum number of samples required. If a TC sample is collected only once at a location but is still representative of water quality in the distribution system, the sample does not have to be identified in the PWS s Monitoring Plan. However, if the PWS plans to collect a sample at the same site again (e.g., every 6 months), the sample must be incorporated into the PWS s Monitoring Plan. Are systems required to include addresses for all upstream and downstream TC sample sites in the Monitoring Plan? For PWSs with 10 or fewer TC monitoring sites, the addresses are provided for all upstream and downstream sites in its Monitoring Plan. For PWSs with more than 10 monitoring sites, a statement is included that a site within five taps upstream or downstream of the original routine site will be selected and the address will be provided to the Department, as necessary. When must a PWS update its Monitoring Plan? Any time a PWS makes a significant change to their administrative and/or operator contact information, population served, source water, treatment, distribution system, or sample sites (i.e., either adding or removing a location), the PWS must submit a revised Monitoring Plan to the Department within thirty (30) calendar days following the effective date of the change (Article ). PWSs only have to submit the updated section of the Monitoring Plan to the Department not the entire document. Can a PWS collect samples from a site more than once a month to meet the number of required samples? Yes, as long as the proposed sampling is representative of the distribution system and is clearly identified in the Monitoring Plan. Appendix A provides both the required number of TC samples that a PWS must collect based on their population served and the recommended number of routine TC sampling sites a PWS should maintain. Who is allowed to collect TC compliance samples? Any staff person who has been trained properly and is functioning under an appropriately certified drinking water operator in responsible charge (ORC) may collect TC compliance samples pursuant to the Department s Facility Operator Certification Program s requirements (Regulation 100, 5 CCR ). Page 6

7 TOTAL COLIFORM RULE COMPLIANCE Do PWSs have to collect samples at regular intervals throughout the compliance monitoring period? Yes. PWSs must collect samples at regular time intervals throughout the month. However, a GW system that serves less than 4,900 people may collect all of the required samples on a single day if they are taken at different sites (Article 5.1.1(c)). The Department recommends that PWSs collect the samples using the following sample intervals 3 : Population Recommended Sampling Intervals 3 Served Range 1 1,000 Sample event occurs once per month 1,001 12,900 Sample event occurs twice a month at regular intervals, unless the PWS is a GW system that serves less than 4,900 people these systems may collect all of the required samples on a single day if they are taken at different sites (Article 5.1.1(c)) 4,901 12,900 Sample events occur twice a month at regular intervals 12,90101 Sample events occur four times a month at regular intervals 25,000 25,001 or more Sample events occur at regular intervals throughout the month SAMPLE LOCATION What happens if a TC sample cannot be collected (e.g., frozen taps, no site access, etc.) at the site identified in the Monitoring Plan? In this case, PWSs must sample at another TC monitoring site. See Appendix A for the number of recommended monitoring sites. Do routine TC samples need to be rotated throughout the distribution system? Please refer to the Monitoring Plan section of this document regarding sample rotation. The CPDWR require that samples must be collected at sites which are representative of water throughout the distribution system (Article 5.1.1(a)). Rotating sample sites is one way for PWSs to meet this requirement. What samples are used for determining compliance? The results of all samples representative of water quality in the distribution system and any repeat samples not invalidated by the Department or the laboratory are included in determining compliance for the TCR MCL (Article 5.7.(d)). Please refer to the Special Purpose section of this document for the definition of special purpose TC samples special purpose samples are not used for determining compliance with the TCR. What are the reporting requirements for TC samples that are representative of distribution water quality but are not analyzed by a certified laboratory? All compliance samples must Page 7

8 TOTAL COLIFORM RULE COMPLIANCE be analyzed by a certified laboratory using an approved method (Article 5.5(d)(2)). If a TC sample is analyzed by a laboratory that is not certified or an approved analytical method was not used for the analysis, the TC sample cannot be used for compliance determination and there are no reporting requirements. What if a PWS collects a TC positive sample at the end of the distribution system? If a PWS collected a TC positive sample at the end of the distribution system, or one tap away from the end of the distribution system, the Department may waive the requirement to collect at least one repeat sample upstream or downstream of the original sample site and specify more appropriate sampling site(s) for the repeat sample monitoring (Article 5.1.2(c)). The PWS must consult with the Department if this situation occurs. PWSs should not collect their TC samples at dead ends, as they may not be representative of water quality in the distribution system. BEST SAMPLING PRACTICES There are many factors to consider when selecting a TC sampling site. Additionally, failure to collect a TC sample properly may result in sample contamination. See Appendix B for best sampling practices. POSITIVE TC INVESTIGATION Do PWSs have to report every TC positive sample to the Department no later than the next business day of learning that the sample was TC positive? No. PWSs only need to report MCL violations or potential acute situations to the Department no later than 24 hours of learning of the violation (Article 5.6(a) and (b)). PWSs still must submit all TC monitoring data to the Department within the first 10 calendar days following the end of the required monitoring period (Article 1.6(a)). However, under the CDPHE Laboratory Services Division s laboratory certification program, laboratories must promptly notify the Department of any TC or E. coli and fecal positive sample but no later than the end of the day when the system is notified of the test result unless the system is notified of the result after the Department office is closed, in which case the system must notify the Department before the end of the next business day. However, in the interest of protecting public health, the Department recommends that laboratories notify the Department and the system as soon as practical but no later than the next business day following the reading of a positive TC, E. coli or fecal sample. Page 8

9 TOTAL COLIFORM RULE COMPLIANCE When is a TC positive investigation report required? After the appropriate repeat samples are collected, a PWS must investigate the reason for any routine TC positive sample (Article 5.2(a)) (Appendix C). What must be included in the investigation report? The PWS must evaluate conditions of the source(s), treatment facilities, storage, and distribution system, including potential cross-connections (Article 5.2(a)). When does the report have to be available? The results of the investigation must be available at the time that repeat sample results become available (Article 5.2.(b)). The scope of the investigation may be modified by the PWS to take into account conditions unique to the PWS s size, sources, and distribution system layout and crossconnection control devices relative to the location of the TC positive sample (Article 5.1.2(a)(2)). Is there a template for the report? Yes. The Department has an investigative report template available on the Department s website at and is also included as Appendix C. How can a water system protect itself from contamination? To properly protect a water system from contamination, systems should: o Properly maintain all water facilities o Have maintained Standard Operating Procedures (SOPs) o Obtain a sanitary easement for each well (if applicable) o Control or eliminate fecal sources that are in close proximity to the source water o Install and maintain backflow preventers o Maintain a minimum pressure of least 20 psi at all points within the distribution system o Maintain a minimum disinfectant residual of 0.2 mg/l as free chlorine or 0.5 mg/l as chloramines (as total or combined) in the distribution system. These values are only the recommended minimum. TIPS FOR INVESTIGATING A TC POSITIVE SAMPLE 1. Check the sample tap for cleanliness 2. Check the well for possible sources of contamination 3. Check the area surrounding the well 4. Make sure there are no leaks in the line between the well and the treatment system 5. Check for holes in the pressure tank bladder, if applicable 6. Make sure that treatment is properly maintained 7. Ensure that the backflow prevention devices are tested and maintained 8. Look for areas where fluid could be siphoned back into the system 9. Collect investigatory samples (i.e., water quality assessment samples, including chlorine residual, turbidity, temperature, etc.) 10. Consider conducting a well inspection Page 9

10 TOTAL COLIFORM RULE COMPLIANCE Systems may target higher residual concentrations based on their water quality and disinfection objectives. SAMPLE INVALIDATION How can a TC sample be invalidated? Based on Article 5.3 and clarification provided by EPA 4, the Department may invalidate a TC sample under the following three scenarios: 1. Improper sample analysis. An improper sample analysis may be caused by a variety of situations, such as laboratory equipment malfunctions, sample container leakage/breakage, or contaminated negative-control samples. For the Department to invalidate a sample under this scenario, the laboratory itself must indicate that the analysis was improper (Article 5.3(a)(1)). 2. Results of a set of repeat samples suggest the problem is associated with a domestic or other non-distribution system plumbing problem. However, subsequent TC negative samples at both the initial tap and at nearby service connections cannot be grounds to invalidate a TC positive sample (Article 5.3(a)(2)). 3. The Department has substantial evidence to support that a TC positive result is due to a circumstance or condition which does not reflect water quality in the distribution system. The Department must document the decision for invalidation and have it signed by the supervisor of the Department official who recommended the decision. The Department must make the signed document available to both the EPA and the public (Article 5.3(a)(3)). Laboratories must invalidate a total coliform sample (unless total coliforms are detected) if any of the following conditions are met (Article 5.3(b)1-3): 1. The sample produces a turbid culture in the absence of gas production using an analytical method where gas formation is examined (e.g., the Multiple-Tube Fermentation Technique) 2. The samples produces a turbid culture in the absence of an acid reaction in the Presence-Absence (P-A) Coliform Test; or 3. The sample exhibits confluent growth or produces colonies too numerous to count with an analytical method using a membrane filter (e.g., Membrane Filter Technique). How can a TC sample site be invalidated? If a sample location no longer represents water quality in the distribution system, the site may be invalidated. PWSs must be aware that the samples sites represent water quality in the distribution system but have historically been testing positive should not be removed from the PWS s Monitoring Plan without a solid technical basis. The PWS must submit a rationale for the invalidation and the Department will review the submittals on a case-by-case basis. Additionally, the Department may Page 10

11 TOTAL COLIFORM RULE COMPLIANCE exercise its authority to revise a PWS s Monitoring Plan in instances where removal of such sites from a Monitoring Plan is not valid and is inconsistent with the protection of public health (Article 5.1.1(a)). What are the sampling requirements for invalidated samples? Whenever a laboratory or the Department invalidates a TC negative sample, the PWS must collect another sample from the same site as the original sample site within 24 hours of being notified of the invalidation and have the sample analyzed for TC. This process must be repeated until the laboratory obtains a valid result (Article 5.3(c)). The rationale for this is that the presence of high levels of heterotrophic bacteria or turbidity in a sample (after incubation) may reflect a problem in the treatment process or in the integrity of the distribution system. What documents or data are needed to invalidate a compliance sample? A PWS must submit the following documents to the Department for review in order for routine distribution system total coliform positive samples to be considered for invalidation. NOTE: This does not guarantee that the samples will be invalidated: o The Department s TCR Positive Sample Invalidation Request Checklist form (Appendix D) o Copies of the results of the required repeat samples o A brief explanation of why the sample was not representative of the water quality in the distribution system o The protocol for sample collection (i.e., the system s Standard Operating Procedure (SOP) for TC sample collection) REPEAT SAMPLING What happens if there is not an acceptable or accessible TC site within 5 taps of the routine site? Pursuant to Article 5.1.2(c) and the Department s Monitoring Plan template, the PWS must collect one repeat sample from the original TC positive site, and at least one repeat sample at a tap within five (5) service connections upstream and at least one repeat sample at a tap within five (5) service connections downstream of the original sampling site. As mentioned above, if a TC positive sample is at the end of the distribution system, or one tap away from the end of the distribution system, the Department may waive the sampling requirement to collect at least one repeat sample upstream or downstream of the original sampling site and specify more appropriate sampling sites for the repeat sample monitoring (Article 5.1.2(c)). Do repeat TC samples have to be collected on the same distribution line as the routine site? Yes. The upstream and downstream repeat samples must be collected on the same distribution system line (e.g., water main) as the original TC positive sample. If a PWS has to Page 11

12 TOTAL COLIFORM RULE COMPLIANCE collect four repeat samples, the fourth repeat sample may be collected anywhere in the distribution system to help locate any possible sources of contamination. A GW system serving 1,000 people or fewer may use a repeat sample collected from a GW source to meet both the TCR and GWR monitoring requirements (Article 13.3(a)(2)(iii)). Do PWSs have to report chlorine residual on repeat TC samples? Yes. Chlorine residual must be reported for all repeat samples that are collected in the distribution system. Does the chlorine residual for repeat TC samples count towards compliance? Yes all routine and repeat samples that have not been invalidated by either the Department or laboratory are used to determine compliance for both total coliform and distribution system disinfectant residual. SPECIAL PURPOSE SAMPLES What is a special purpose sample? While PWSs must submit all TC sample results that are representative of water quality in the distribution system, PWSs do not have to submit special purpose samples to the Department. Special purpose samples are defined as samples that are taken to determine whether disinfection practices are sufficient following distribution system repair/replacement activities (Article 5.1.1(f)) or samples that are collected in response to customer requests that are not representative of water quality in the distribution system. If a customer requests a TC sample, would that be considered a special purpose sample? All customer requested samples must be identified as special purpose samples, as long as the samples are not representative of water quality in the distribution system (e.g., samples are collected after a filtration device, the sample site is located at a dead end of the distribution system, etc.). PWSs must evaluate the sample location and determine if the sample is representative of water quality in the distribution using the Total Coliform Rule Customer Requested Special Purpose Sample Verification Form in Appendix E. If the sample is not representative of water quality in the distribution system, the PWS must label the sample as special purpose and retain the Total Coliform Rule Customer Requested Special Purpose Sample Verification Form for its records. PWSs must provide the Total Coliform Rule Customer Requested Special Purpose Sample Verification Form upon request by the Department. Please refer to the Monitoring Plan section of this document regarding when and how customer requested samples should be included in the Monitoring Plan. If the sample is representative of water quality in the distribution system, the PWS must report the customer requested samples as routine using the Department s normal Page 12

13 TOTAL COLIFORM RULE COMPLIANCE reporting forms. Please refer to the Monitoring Plan section of this document regarding when and how customer requested samples should be included in the Monitoring Plan. If a PWS returns a distribution system line to service, due to routine maintenance or in response to a line break, and collects a TC sample after the line was returned to service, how should this sample be labeled? Samples that are collected in response to distribution system maintenance and/or repair must be labeled as special purpose, even if the line has been returned to service (Article 5.1.1(f)). PRIMARY REPORTING REQUIREMENTS Do PWSs have to notify the Department of every TC positive sample within the next business day? No. PWSs are not required to notify the Department of every positive TC sample within the next business day of learning about the TC positive sample. PWSs must still submit their monitoring data to the Department within the first 10 calendar days following the end of the required monitoring period (Article 1.6.4(a)). However, pursuant to Article 5.6(a), PWSs must notify the Department within the next business day for the following: o Monthly MCL violation: the violation must be reported to the Department no later than the end of the next business day after the PWS learns of the violation. The public must be notified within 30 days after the PWS learns of the violation. o Acute MCL violation: the violation must be reported to the Department no later than the end of the next business day after the PWS learns of the violation. The public must be notified as soon as practical but no later than 24 hours after the PWS learns of the violation. NOTE: An acute violation is defined as when any fecal coliform-positive or repeat sample or E. coli-positive repeat sample, or any TC positive repeat sample following a fecal coliform-positive sample or E. coli positive routine sample occurs (Article 5.7(b)). If a PWS learns of an acute violation within normal business hours, PWSs must call the TCR Hotline at or ext If the PWS learns of an acute violation after hours, PWSs must call the Department s 24-hour Environmental Release/Incident Report Line at o PWSs with routine or repeat samples that are fecal-coliform or E. coli positive: the PWS must notify the Department as soon as possible but no later than the end of the next business day following the day on which the PWS was notified of the test result (Article 5.4.(b)). Page 13

14 TOTAL COLIFORM RULE COMPLIANCE What are the reporting requirements for TC samples that are collected in the distribution system but are not identified in the Monitoring Plan? If the TC samples were representative of distribution system water quality, were analyzed by a laboratory certified by the Department, and were analyzed using an approved method, the samples must be submitted to the Department as routine TC samples. These samples must be included in the PWS s compliance determination calculation. What are the reporting requirements for TC samples collected by others without the PWS s knowledge but are analyzed by a certified laboratory? Samples collected by customers without the PWS s knowledge cannot be used to determine compliance. REFERENCES 1. Colorado Department of Public Health and Environment, 5 CCR , Colorado Primary Drinking Water Regulations, November 30, United States Environmental Protection Agency (USEPA). Ground Water Rule: Final Rule. Federal Register Vol. 71, No. 216, pp pp November Texas Commission on Environmental Quality. Coliform Sampling for Public Water Systems. August RG United States Environmental Protection Agency (USEPA). Invalidation of Total Coliform Positive Samples. Office of Water. April Colorado Department of Public Health and Environment, 5 CCR , Water and Wastewater Facility Operators Certification Requirements, Regulation 100. Page 14

15 TOTAL COLIFORM RULE COMPLIANCE Appendix A. Total Coliform Monitoring Frequency for Community Water Systems (CWSs) Population Served per Day Required Minimum Number of Samples per Month Recommended Number of Routine Sample Sites 3 (Article Table 5.1) 25-1, ,001-2, ,501-3, ,301 4, ,101 4, ,901 5, ,801 6, ,701 7, ,601 8, ,501 12, ,901 17, ,201 21, ,501 25, ,001 33, ,001 41, ,001 50, ,001 59, ,001 70, ,001 83, ,001 96, , , , , , , , , , , , , , , ,001 1,230, ,230,001-1,520, ,520,001 1,850, ,850,001 2,270, ,270,001 3,020, ,020,001 3,960, ,960,001 or more 480 At least 5 At least the same number of sample sites as samples. Example: a system that collects 9 samples should have at least 9 sample sites. At least 30 Half the number of sample sites as samples. Example: a system that collects 240 samples should have at least 120 sample sites. Page 15

16 TOTAL COLIFORM RULE COMPLIANCE Appendix B. Best Sampling Practices Water samples to be analyzed for bacterial content must be collected in bottles that are of the minimum volume required in the analytical method and that have been properly sterilized. Each sterilized bottle contains a white powder or clear liquid called sodium thiosulfate. This chemical is used to dechlorinate the water when water is disinfected by chlorine. The sodium thiosulfate will have no effect on the water sample other than to dechlorinate the sample. Obtaining sampling bottles that are specially prepared by a Colorado-certified laboratory will help to ensure that volume, dechlorination and sterilization needs are met. For a list of certified laboratories, contact the Water Quality Control Division at (303) or visit the CDPHE s Laboratory Services Division s website at Systems should consider avoiding collecting samples from kitchen or utility sinks with swing arm necks and/or aerators. It also is not a good idea to collect water samples from outside taps or hoses. The potential for contamination of these potential sampling sites is high and may result in a positive total coliform or E. coli sample that is not truly representative of water quality in the distribution system. Systems must weigh the risks of the sample locations they select. The bathtub faucet or bathroom sink faucet are usually the most reliable places to collect a sample.. Systems should not collect a sample from a tap or faucet that is leaking. Again, systems must weigh the risks of the sample locations they select. PROCEDURE: 1. WASH YOUR HANDS - Poor hygiene can result in samples becoming contaminated. 2. Carefully remove the aerator, if applicable. 3. Allow the COLD water to run freely for 3 to 5 minutes to flush the pipes. 4. Measure the disinfectant residual. 5. Disinfect the faucet by either flaming the tap or spray the faucet using a strong bleach-chlorine solution. 6. Keep the bottle closed until the moment of collecting the sample. Remove any seal on the bottle and discard. Carefully remove the lid without touching any part of the bottle or lid that will come in direct contact with the water sample. DO NOT RINSE THE BOTTLE BEFORE COLLECTING THE SAMPLE! 7. Using a pencil-sized stream of water (approximately ¼ inch diameter), fill the sample bottle to the 100 milliliters of water line. DO NOT FILL THE BOTTLE FULL. Leave an air space at the top. 8. Fill and close the bottle in one step. Secure the lid tightly. 9. Package the sample appropriately. 10. Submit the sample, along with the corresponding paperwork, to a laboratory certified by the State of Colorado for bacteriological drinking water testing. Page 16

17 Appendix C. TCR Positive Investigation Report Template This form is intended to assist public water systems in completing the investigation required by section 5.2 of the Colorado Primary Drinking Water Regulations and may be modified to take into account conditions unique to the system. ADMINISTRATIVE INFORMATION Entity Name: PWSID NUMBER: Operator in Responsible Charge (ORC) Person that collected TC samples if different than ORC Owner Certified Laboratory for Microbiological Analyses Date Investigation Completed: Name Address Telephone Number SOURCE 1. Inspect each well head for physical defects and report a. Is raw water sample tap upstream from point of disinfection? b. Is wellhead vent pipe screened? c. Is wellhead seal watertight? d. Is well head located in pit or is any piping from the wellhead submerged? e. Does the ground surface slope towards well head? f. Is there evidence of standing water near the wellhead? g. Are there any connections to the raw water piping that could be cross connections? (describe all connections in comments) h. Is the wellhead secured to prevent unauthorized access? i. To what treatment plant does this well pump? j. How often do you take a raw water total coliform (TC) test? k. Provide the date and result of the last TC test at this location WELL WELL WELL WELL COMMENTS

18 TOTAL COLIFORM RULE COMPLIANCE TREATMENT 1. Inspect each point where disinfectant is added and report a. For hypochlorinator systems 1. Is the disinfectant feed pump feeding disinfectant? 2. What is the feed rate of disinfectant in ml/minute 3. What is the concentration of the disinfectant solution being fed? (percent, or mg/l of chlorine as HOCl) 4. By what method was the concentration of solution determined? (ex: measured, manufacturer s literature) 5. What is the age (days) of the disinfectant solution currently being used at this treatment location? 6. What is the raw water flow rate at the point where disinfectant is added in gallons per minute? 7. What is the total chlorine residual measured immediately downstream from the point of application? 8. What is the free chlorine residual measured immediately downstream from the point of application? 9. What is the contact time in minutes from the point of disinfectant application to the first customer? PLANT (NAME) PLANT (NAME) PLANT (NAME) PLANT (NAME) COMMENTS STORAGE 1. Is each tank locked to prevent unauthorized access? 2. Is the vent of each tank screened? 3. Does the tank float on the distribution system or are there separate inlet and outlet lines? 4. What is the measured chlorine residual (total/free) of the water exiting the TANK TANK TANK TANK COMMENTS Page 18

19 TOTAL COLIFORM RULE COMPLIANCE STORAGE storage tank today? 5. Are there any unsealed openings in the tank such as access doors, vents or joints? 6. What is the volume of the storage tank in gallons? 7. Is the tank baffled? TANK TANK TANK TANK COMMENTS DISTRIBUTION SYSTEM SYSTEM RESPONSES 1. What is the minimum pressure you are maintaining in the distribution system? 2. Has the distribution system been worked on within the last week (e.g., taps, hydrant flushing, main breaks, mainline extensions, etc.)? If yes, provide details. 3. Are there any signs of excavations near your distribution system not under the direct control of your maintenance staff? 4. On what date was the distribution system last flushed? 5. Is there a written flushing procedure you can provide for our review? 6. Do you have an active cross connection control program? 7. On what date was the system last surveyed to identify cross connections? TOTAL COLIFORM SAMPLING INFORMATION Sample 1 Sample 2 Sample 3 Sample 4 Total Coliform ROUTINE Sampling Locations 1. Describe the actual sample tap (exterior hose bib, bath tub, etc.) 2. Describe how the tap was treated in preparation for sample collection (ran water, swabbed with disinfectant, flamed, etc.) Page 19

20 TOTAL COLIFORM RULE COMPLIANCE TOTAL COLIFORM SAMPLING INFORMATION Sample 1 Sample 2 Sample 3 Sample 4 3. Is this sample tap designated on the sampling plan submitted with this information request? Total Coliform REPEAT Sampling Locations 1. Describe the actual sample tap (exterior hose bib, bath tub, etc.) 2. Describe how the tap was treated in preparation for sample collection (ran water, swabbed with disinfectant, flamed, etc.) 3. Is this sample tap designated on the sampling plan submitted with this information request? ADDITIONAL INFORMATION TO BE SUBMITTED WITH RESPONSES TO THE ABOVE QUESTIONS 1. Sketch of System showing all sources, treatment locations, storage tanks, microbiological sampling sites and general layout of the distribution system including the location of all hazardous connections such as the wastewater treatment facility. 2. Copy of the microbiological monitoring plan as required by Article 3.1.1(1) of the CPDWR s. 3. Name, certification level and certificate number of the Operator in Responsible Charge. 4. Copy of the last cross connection survey performed that identifies the location of all unprotected cross connections. SUMMARY: BASED ON THE RESULTS OF YOUR INVESTIGATION AND ANY OTHER INFORMATION AT YOUR DISPOSAL, WHAT DO YOU BELIEVE TO BE THE CAUSE OF THE POSITIVE TOTAL COLIFORM SAMPLES FROM YOUR PUBLIC WATER SYSTEM? CERTIFICATION: I CERTIFY THAT THE INFORMATION SUBMITTED IN RESPONSE TO THE QUESTIONS ABOVE IS ACCURATE TO THE BEST OF MY PROFESSIONAL KNOWLEDGE NAME: TITLE: DATE: Page 20

21 Appendix D. TCR Positive Sample Invalidation Request Form PWSID: System Name: Total Coliform Rule Positive Sample Invalidation Request Checklist WQCD Drinking Water CAS 4300 Cherry Creek Drive South; Denver, CO Fax: (303) ; Public Water System Information Contact Person: Phone #: Address: System Authorized Signature Printed Name Title Date Sample Invalidation Information Collection Date/Time: Sample ID: Sample Site Name: Sample Site Description: Active Service Connection: Location: Sample Collector Information Collector's Name: Employed by: Years Experience: Sample Collection Information Disinfectant Used: Chlorine Residual: mg/l Sample Point Disinfected Using: SOP Followed: Distribution System Cross-Connection Program Used: Flushing Frequency: Conditions Existing at the Time of Sample Collection Water Outage in Area of Positive Sample: Lowest Pressure: psi Date of Most Recent Flushing: Repair of Well/Distribution System in Area of the Positive Sample: Repair Date: Special Purpose Samples Collected Following Repair: Any Special Purpose Sample TC Positive: Any System Public Notice Issued in the Last 6 Months: Type of Violation:

22 TOTAL COLIFORM RULE COMPLIANCE Weather Conditions at the Time of Collection (if applicable) Wind Speed: mph Raining or Snowing at the Time of Collection: Corrective Actions Performed SOP Modified: System Flushed: Additional Operator Training: Page 22

23 TOTAL COLIFORM RULE COMPLIANCE Appendix E. TCR Customer Requested Special Purpose Bacteriological Sample Verification Total Coliform Rule Customer Requested Special Purpose Sample Verification WQCD Drinking Water CAS Please Retain for your Records. PWSID: System Name: Public Water System Information Contact Person: Phone #: Sample Site Information Collection Date/Time: Sample Address: Sample Site Description: Sample Collector Information Collector's Name: Laboratory Name: Special Purpose Sample Verification Was the sample collected at a site not representative of distribution system water quality (e.g., at dead end)? Was the sample collected after any treatment (e.g., home filter, water softener, etc.)? Did staff observe any obvious plumbing issues (e.g., cross-connection) at the site location? Were there any environmental conditions at the site that would cause the sample to not be representative of water quality in the distribution system? Were there any other issues with the sample site? Please provide any additional information regarding the sample site: If any of the items above were checked "yes" and there was sufficient evidence that the sample was not reflective of distribution system water quality, the sample should be labeled as "Special Purpose". If the sample is not representative of water quality in the distribution system, the PWS must retain this form for its records and provide the forms upon request by the Department. Page 23