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TOTAL COLIFORM MONITORING 40 CFR 141.21

TOTAL COLIFORM MONITORING 40 CFR 141.21. TRANSIENT NON-COMMUNITY PUBLIC WATER SYSTEMS. COLIFORM SAMPLING CFR 141.21 (a). Routine Monitoring Written sample siting plan Sites must represent water throughout distribution system Plans subject to State review and revision.

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TOTAL COLIFORM MONITORING 40 CFR 141.21

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  1. TOTAL COLIFORM MONITORING40 CFR 141.21 TRANSIENT NON-COMMUNITY PUBLIC WATER SYSTEMS

  2. COLIFORM SAMPLINGCFR 141.21 (a) • Routine Monitoring • Written sample siting plan • Sites must represent water throughout distribution system • Plans subject to State review and revision

  3. MONITORING FREQUENCYGroundwater System CFR 141.21 (a) (3) (i) • Monitor each calendar quarter when water served to public • Monthly monitoring suggested • State can reduce monitoring to once/year • System must be free of sanitary defects Daily Population: 25 to 1,000 Persons

  4. Minimum Samples/Month* Population Served (average daily) 2 1,001 to 2,500 3 2,501 to 3,300 4 3,301 to 4,100 *40 CFR 141.21 (a) (2) MONITORING FREQUENCYGroundwater System (continued)

  5. Minimum Samples/Month* Population Served (average daily) 1 25 to 1,000 1,001 to 2,500 2 2,501 to 3,300 3 *40 CFR 141.21 (a) (2) MONITORING FREQUENCY Surface Water and GW Under Influence

  6. ROUTINE SAMPLE INTERVALS CFR 141.21 (a) (4) • PWS must collect samples at regular time intervals throughout the month, except GW systems serving 4,900 and fewer. Those systems may collect all required samples on a single day if they are taken from different sites.

  7. ROUTINE SAMPLE COLLECTION Helpful Hints Always Collect - early in the week - early in the month - early in the compliance period Early collection allows time to collect repeat samples, if routine sample is total coliform positive.

  8. FECAL COLIFORM OR E. COLI TESTING OF ROUTINE SAMPLES CFR 141.21 (e) • Any routine or repeat sample that is TC+ must be analyzed for the presence of fecal coliforms or E. coli. • If FC+ or EC+, the system must notify the State by the end of the day when the system is notified of the result, unless the State office is closed at that time. In such a case, the State must be notified before the end of the next business day.

  9. FC OR EC COLIFORM TESTINGCFR 141.21 (e) (continued) • State may waive fecal or E. coli testing if the system assumes the TC+ sample is also FC+ or EC+. • State waiver is made on a case-by-case basis • System must notify State by the end of the day when the system is notified of the result, unless the State office is closed at that time. In such a case, the State must be notified before the end of the next business day.

  10. REPEAT MONITORING CFR 141.21 (b) WHEN? • Collect repeats within 24 hours of being notified of positive routines (State may extend on case by case basis.) • Collect all repeats on the same day

  11. REPEAT MONITORING HOW MANY? • If PWS Collects One or Fewer Routines/Month • Collect four repeat samples for each TC+ routine sample • If PWS Collects >1 Routine Sample/Month • Collect three repeat samples for each TC+ routine sample

  12. REPEAT MONITORING • At least one repeat at tap where original TC+ sample taken • At least one repeat sample within five service connections upstream of original site WHERE?

  13. REPEAT MONITORING • At least one repeat sample within five service connections downstream of original site • Location of fourth sample collected at the discretion of the PWS WHERE? (continued)

  14. SYSTEMS WITH A SINGLE SERVICE CONNECTIONCFR 141.21 (b) (3) • Samples can be collected in a single large volume or as 100ml samples in multiple containers • Collect all samples on the same day OR • Collect samples over a four day period

  15. RECOMMENDED REPEAT COLLECTION METHOD • Ideal method is to collect samples over a four day period. • If unable to collect over four days, then collect four separate samples spaced throughout a single day.

  16. RECOMMENDED REPEAT COLLECTION METHOD (continued) • Four separate samples recommended over a single large volume sample because: • Increases probability of capturing coliforms, if present, since contamination may be intermittent

  17. POSITIVE REPEAT SAMPLES CFR 141.21 (b) (4) • If one or more repeats is TC+, then collect a set of four repeats for each TC+ sample. • Repeat process until no detection of TC in one set of repeats or the MCL is exceeded and State has been notified • Collect samples within 24 hours of being notified of positive results. • State may extend on case-by-case basis

  18. ADDITIONAL ROUTINES CFR 141.21 (b) (5) If a system collects fewer than five routine samples/month and has one or more TC+ sample(s) which are not invalidated, it must collect at least five routine samples during the next month the system provides water to the public. The State may waive this requirement on a case-by-case basis.

  19. State may waive the requirement to collect five routines the next month the system provides water in one of the two following cases: 1. A State approved agent performs a detailed site visit before the end of the next month the system provides water to the public. The inspecting agent cannot be an employee of the water system. STATE WAIVER FOR COLLECTION OF ADDITIONAL ROUTINES 141.21 (b) (5) (i)

  20. STATE WAIVER (continued) 2. The State determines the cause of the TC+ sample and establishes that the system has corrected the problem before the end of the next month the system serves water to the public. If so, the State must a. Document the waiver in writing b. Approve and sign the document c. Make document available to EPA and public

  21. MAXIMUM CONTAMINANT LEVEL(MCL) COMPLIANCE DETERMINATION CFR 141.21 (b) (7) • All valid routine and repeat results must be included in determining compliance with the MCL for total coliforms. • Invalidated TC+ samples do NOT count toward compliance

  22. (MCLs) FOR MICROBIOLOGICAL CONTAMINANTS CFR 141.63 • The MCL is based on presence/absence of total coliforms in a sample. • Systems collecting fewer than 40 samples/month are in compliance with the MCL for TC, if no more than one sample collected during a month is TC+. • Systems collecting at least 40 samples/month are in compliance, if no more than 5.0% of the samples collected during a month are TC+.

  23. MCL COMPLIANCE CHART FOR MICROBIOLOGICAL CONTAMINANTS

  24. STATE INVALIDATION OF TOTAL COLIFORM SAMPLES CFR 141.21 (1) (c)(i - iii) • Lab establishes improper analysis caused result OR • Repeat sample(s) at original TC+ tap are positive, all others negative (not so for single service connections) OR • Positive result is unrelated to water quality in distribution system TC+ Samples Invalidated by State

  25. STATE INVALIDATION OF TOTAL COLIFORM SAMPLES(continued) • If State invalidates because result is unrelated to water quality • Decision, rationale and corrective action must be in writing • Approved and signed by supervisor • Document available to EPA and public • Water system must still collect all repeat samples and use them to determine compliance with the MCL

  26. LAB INVALIDATION OF TOTAL COLIFORM SAMPLES CFR 141.21 (c) (2) • A lab must invalidate a total coliform sample (unless TC+) if test results reveal heterotrophic interference (HI). • System must collect a replacement sample from the same location as the original sample. Collection must be within 24 hours of being notified of the HI.

  27. HETEROTROPHIC INTERFERENCE Non-coliform bacteria which are better than coliforms at surviving in the environment may be present in the sample. If these organisms are given a chance to grow, they may out-compete coliforms during analysis and may limit the analysts ability to detect coliforms. The effect of HI is an underestimation of coliform numbers or a false negative result.

  28. Old sample (received after 30 hours) Container broken in transit Insufficient quantity No date/time of collection Frozen Leaked REASONS SAMPLES MAY BE REJECTED FOR ANALYSIS COLLECT REPLACEMENT SAMPLES FOR ALL OF THE ABOVE CASES

  29. PUBLIC NOTIFICATION (PN)CFR 141.32 A PN IS REQUIRED WHEN A SYSTEM: • Fails to Monitor (FTM) for Total Coliforms • Routine monitoring • Repeat monitoring • Additional routine monitoring the month following a TC+ routine • Exceeds the MCL for Total Coliforms

  30. PN REQUIREMENTS FOR FTM FOR TOTAL COLIFORMS CFR 141.32 • Within three months of the FTM, non-community PWS’s must • Continuously post the notice in a conspicuous place for as long as the violation exists, or • Directly deliver the notice by hand • Repeat hand delivery every three months for as long as the violation exists

  31. PN REQUIREMENTS FORNON-ACUTE MCL VIOLATIONS CFR 141.32 • Within 14 days of the TC non-acute violation, non-community PWS’s must • Continuously post the notice in a conspicuous place for as long as the violation exists, or • Directly deliver the notice by hand • Repeat hand delivery every three months for as long as the violation exists

  32. PN REQUIREMENTS FORACUTE MCL VIOLATIONS CFR 141.32 • Within 72 hours of the TC acute violation, non-community PWS’s must • Continuously post the notice in a conspicuous place for as long as the violation exists, or • Directly deliver the notice by hand • Repeat hand delivery every three months for as long as the violation exists

  33. GENERAL CONTENT OF PNCFR 141.32 • The PN must provide • A clear explanation of the violation • Potential adverse health effects • Population at risk • Corrective steps taken by the PWS • The need to seek alternative water supplies, if any • Preventative measures the consumer should take • Name and number of a contact person

  34. PN REPORTING REQUIREMENTSCFR 141.31 • The PWS, within ten days of completion of each public notification, shall submit to the State a copy of each type of notice that was made available to the persons served by the system.

  35. ALWAYS DRINK UPSTREAM FROM THE HERD!!!

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