The department may invalidate a total coliform-positive sample only if one of the following conditions is met:
A laboratory must invalidate a total coliform sample, unless total coliforms are detected, only if one of the following conditions is met:
Systems must collect a replacement sample for total coliform bacteria analysis from the same location as the original sample if the original sample is invalidated by the department or laboratory. Replacement samples must be collected within twenty-four hours of notification by the department or laboratory and submitted for total coliform analysis. The system must continue to resample within twenty-four hours and have the sample analyzed for total coliforms until a valid result is obtained. The department may waive the twenty-four hour time limit on a case-by-case basis.
Criteria the department may implement for waiving the twenty-four hour sampling time frame includes the following:
POPULATION SERVED | MINIMUM NUMBER OF SAMPLES PER MONTH |
25 to 1,000 | 1 |
1,001 to 2,500 | 2 |
2,501 to 3,300 | 3 |
3,301 to 4,100 | 4 |
4,101 to 4,900 | 5 |
4,901 to 5,800 | 6 |
5,801 to 6,700 | 7 |
6,701 to 7,600 | 8 |
7,601 to 8,500 | 9 |
8,501 to 12,900 | 10 |
12,901 to 17,200 | 15 |
17,201 to 21,500 | 20 |
21,501 to 25,000 | 25 |
25,001 to 33,000 | 30 |
33,001 to 41,000 | 40 |
41,001 to 50,000 | 50 |
50,001 to 59,000 | 60 |
59,001 to 70,000 | 70 |
70,001 to 83,000 | 80 |
83,001 to 96,000 | 90 |
96,001 to 130,000 | 100 |
130,001 to 220,000 | 120 |
220,001 to 320,000 | 150 |
320,001 to 450,000 | 180 |
450,001 to 600,000 | 210 |
600,001 to 780,000 | 240 |
780,001 to 970,000 | 270 |
970,001 to 1,230,000 | 300 |
1,230,001 to 1,520,000 | 330 |
1,520,001 to 1,850,000 | 360 |
1,850,001 to 2,270,000 | 390 |
2,270,001 to 3,020,000 | 420 |
3,020,001 to 3,960,000 | 450 |
3,960,001 or more | 480 |
Following any total coliform-positive sample taken, systems must comply with the repeat monitoring requirements and E.coli analytical requirements as specified in title 40 Code of Federal Regulations part 141, subpart Y.
As set forth under title 40 Code of Federal Regulations part 141, subpart Y, once all routine and repeat monitoring for a calendar month has been completed, either the system or the department must determine whether any coliform treatment technique triggers have been exceeded. The system must complete any assessments associated to the triggers.
All repeat samples must be collected on the same day except that the department may allow systems with a single service connection to:
If one or more repeat samples in the set of required repeat samples is total coliform-positive, an additional set of repeat samples must be collected, within twenty-four hours unless the department extends the twenty-four hour time frame, meeting the requirements set forth under title 40 Code of Federal Regulations part 141, subpart Y. Additional sets of repeat samples must be collected until no total coliform bacteria are detected in one complete set or the department determines a coliform treatment technique trigger as specified in title 40 Code of Federal Regulations part 141, subpart Y, has been exceeded as a result of a repeat sample being total coliform-positive. If a coliform treatment technique trigger, as identified in this provision, has been exceeded as a result of a routine sample being total coliform-positive, the system only needs to conduct one round of repeat monitoring for each total coliform-positive routine sample. The system shall report to the department and notify the public when an E.coli maximum contaminant level is exceeded.
After a system collects a routine sample and before it learns the results of that sample, if the system collects another routine sample from within five adjacent service connections of the first sample, and the first sample, after analysis, is found to contain total coliform bacteria, the system may count the subsequent sample as a repeat sample instead of a routine sample.
All routine and repeat results taken under title 40 Code of Federal Regulations part 141, subpart Y, and not invalidated by the department or laboratory, must be used to determine whether a coliform treatment technique trigger, under the provision stated above, has been exceeded.
A level 1 assessment must be conducted by the water system operator or by a consultation, such as a phone interview or onsite visit, with the department.
When completing the level 1 assessment, the system must describe sanitary defects found, what corrective actions were completed, the proposed time frame for any remaining corrective actions that need to be addressed, and any other department directives that may be required. The system may note on the assessment form that no sanitary defects were identified.
Within thirty days after learning of a treatment technique trigger exceedance, the system must submit a completed level 1 assessment form to the department. The department may extend the thirty-day time frame on a case-by-case basis.
The department shall review the completed level 1 assessment and determine if the assessment is sufficient. The assessment form must include proposed time frames for any corrective actions not completed. If the department determines the level 1 assessment not to be sufficient, the department shall consult with the system. If the department requires any revisions to the level 1 assessment, the system must submit, to the department, a revised level 1 assessment form on an agreed-upon schedule that will not exceed thirty days from the date of the consultation.
The department shall review the completed assessment form and determine if the cause of the level 1 assessment was found. If the cause of the level 1 assessment was found, the system must describe how the problem was corrected. The department shall determine on a case-by-case basis the schedule for any corrective actions that need to be addressed.
A level 2 assessment will be conducted by the department or department-approved assessors. A system may conduct a level 2 assessment if the system has personnel with the certification or qualifications as specified by the department. A system must have personnel with an operator certification level one level higher than the water system being evaluated.
When completing the level 2 assessment, the system must describe sanitary defects found, what corrective actions were completed, the proposed time frame for any remaining corrective actions that need to be addressed, and any other department directives that may be required. The system may note on the assessment form that no sanitary defects were identified.
Within thirty days after learning of a treatment technique trigger exceedance, the system must submit a completed level 2 assessment form to the department. The department may extend the thirty-day time frame on a case-by-case basis.
The department shall review the completed level 2 assessment and determine if the assessment is sufficient. The assessment form must include proposed time frames for any corrective actions not completed. If the department determines the level 2 assessment not to be sufficient, the department shall consult with the system. If the department requires any revisions to the level 2 assessment, the system must submit, to the department, a revised level 2 assessment form on an agreed-upon schedule that does not exceed thirty days from the date of the consultation.
The department shall review the completed assessment form and determine if the cause of the level 2 assessment was found. If the cause of the level 2 assessment was found, the system must describe how the problem was corrected. The department shall determine on a case-by-case basis the schedule for any corrective actions that need to be addressed.
Community ground water systems, including systems purchasing ground water, that are not providing at least four-log treatment of viruses and have not been determined by the department to exhibit outstanding performance shall undergo a sanitary survey no less frequently than once every three years. Community ground water systems, including systems purchasing ground water, which are providing at least four-log treatment of viruses or which have been determined by the department to exhibit outstanding performance shall undergo a sanitary survey no less frequently than once every five years.
Noncommunity ground water systems, including systems purchasing ground water, which are not providing at least four-log treatment of viruses shall undergo a sanitary survey no less frequently than once every three years. Noncommunity ground water systems, including systems purchasing ground water, that are providing at least four-log treatment of viruses shall undergo a sanitary survey no less frequent than once every five years.
The department will allow sanitary surveys to be phased. The components of the phased sanitary survey must be completed within the established frequency.
The department shall review the sanitary surveys for systems serving one thousand persons or less to determine if the system is taking the proper number of monthly total coliform bacteria samples.
Public water systems are responsible for ensuring that the required sanitary surveys are conducted.
N.D. Admin Code 33.1-17-01-11
General Authority: NDCC 61-28.1-03; S.L.2017, ch.199, § 1
Law Implemented: NDCC 61-28.1-03; S.L.2017, ch.199, § 69