&EPA
United States
Environmental Protection
Agency
ROUTINE
MONITORING
Total Coliform Rule Monitoring Requirements
Noncommunity Water Systems Serving 1,001 -10,000 People*
REPEAT MONITORING
POSITIVE REPEAT SAMPLES AND
MCL VIOLATIONS
Non-community water systems serving more than 1,000 persons during any
month must sample at regular time intervals throughout the month except for
ground water systems that serve 4,900 persons or less.
Ground water systems serving 4,900 persons or less may collect all required
samples on a single day if they are taken from different sites.
You must sample at the sites in your distribution system identified in your pri-
macy agency reviewed sampling plan.
The number of samples you collect depends on the number of people you serve
(see Table A).
If you take 4 or fewer routine samples every month or quarter, you are required
to take 5 routine samples in the month following a total coliform (TC) positive
result, even if you are on a quarterly schedule. For example, if you took 3 routine
samples in June and 1 sample was TC-positive, you must take 5 routine samples
in July.
Table A: TCR Routine Monitoring*
Population
1,001-2,500
2,501-3,300
3,301-4,100
4,101-4,900
4,901 - 5,800
5,801 - 6,700
6,701 - 7,600
7,601 - 8,500
8,501-12,900
# of Routine Samples per Month
2
3
4
5
6
7
8
9
10
You must collect repeat samples whenever you are noti-
fied of a TC-positive sample. The positive routine sample
must also be analyzed for either fecal coliform or £ Co//.
You must take at least 3 repeat samples for every TC-
positive sample; for example if you had 2 TC-positive
samples, you must take at least 6 repeat samples.
If you have more than 1 service connection, you must
collect repeat samples within 24 hours of learning about
the positive results (unless your primacy agency gives
you more time).
If you have only 1 service connection, your primacy
agency may give you approval to collect repeat samples
within 4 days of learning of the positive result.
You must collect at least 1 repeat sample from each of the
sites identified below:
* The tap where the routine TC-positive was taken.
* A tap within 5 service connections upstream of the tap
where the routine TC-positive was taken.
* A tap within 5 service connections downstream of the
tap where the routine TC-positive was taken.
If a repeat sample is positive, you must continue to collect repeat samples, per repeat monitoring
instructions, until TC is no longer positive or until there is an MCL violation. If a repeat sample is
TC-positive, it must also be analyzed for either fecal coliform or £ Co//.
If you have 2 or more TC-positive samples in 1 month (including both repeat and routine samples),
your system has a monthly MCL violation.
If you have any fecal coliform or £ Co// positive repeat samples or have a
fecal coliform or £ Co// positive sample followed by a TC-positive repeat sample, your system has
an acute MCL violation.
Besides sampling, what else are we required to do?
There are also requirements on whatyou report to the primacy agency every month, and require-
ments on how and when to notify your customers if you have a violation. Contact your primacy
agency to make sure you are providing them with all the information that is required.
Where can I find more information on the
Total Coliform Rule?
You can find more information on the Total Coliform
Rule by calling EPA's Safe Drinking Water Hotline at:
1.800.426.4791; or you can visit EPA's Total Coliform Rule
Web site:
http://www.epa.gov/safewater/disinfection/tcr/
index.html.
* Requirements for systems serving <1000 are summarized on a separate
Placard (EPA 816-F-08-007)
Primacy Agency.
(contact name and phone number)
Office of Water (4606M) EPA816-F-08-006 www.epa.gov/safewater January, 2008
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