Section 611.601 Monitoring Frequency

Section 611

TITLE 35: ENVIRONMENTAL PROTECTION

SUBTITLE F: PUBLIC WATER SUPPLIES

CHAPTER I: POLLUTION CONTROL BOARD

PART 611 PRIMARY DRINKING WATER STANDARDS

SECTION 611.601 MONITORING FREQUENCY

Section 611.601  Monitoring

Frequency

Monitoring must be conducted as

follows:

a)         Required Sampling

1)         Each supplier must take a minimum of one sample at each

sampling point at the times required by Section 611.610 beginning in the

initial compliance period.

2)         Each sampling point must produce samples that are

representative of the water from each source after treatment or from each

treatment plant, as required by subsection (b).  The total number of sampling

points must be representative of the water delivered to users throughout the

PWS.

3)         The supplier must take each sample at the same sampling point unless

conditions make another sampling point more representative of each source or

treatment plant and the Agency has granted a SEP under subsection (b)(5).

b)         Sampling Points

1)         Sampling points for GWSs.  Unless otherwise provided by SEP, a

GWS supplier must take at least one sample from each of the following points:

each entry point that is representative of each well after treatment.

2)         Sampling points for an SWS or a mixed system supplier.  Unless

otherwise provided by SEP, an SWS or mixed system supplier must take at least

one sample from each of the following points:

A)        Each entry point after the application of treatment; or

B)        A point in the distribution system that is representative of

each source after treatment.

3)         If a supplier draws water from more than one source, and the

sources are combined before distribution, the supplier must sample at an entry

point during periods of normal operating conditions when water is

representative of all sources being used.

4)         Additional sampling points

B)        A point in the distribution system that is representative of

each source after treatment.

3)         If a supplier draws water from more than one source, and the

sources are combined before distribution, the supplier must sample at an entry

point during periods of normal operating conditions when water is

representative of all sources being used.

4)         Additional sampling points.  The Agency must, by SEP,

designate additional sampling points in the distribution system or at the

consumer's tap if it determines that additional samples are necessary to more

accurately determine consumer exposure.

5)         Alternative sampling points.  The Agency must, by SEP, approve

alternate sampling points if the supplier demonstrates that the points are more

representative than the generally required point.

c)         This subsection corresponds with 40 CFR 141.23(a)(4), an

optional provision relating to compositing of samples that USEPA does not

require for state programs.  This statement maintains structural consistency

with USEPA rules.

d)         The frequency of monitoring for the following contaminants

must be in compliance with the following Sections:

1)         Asbestos:  Section 611.602;

2)         Antimony, arsenic, barium, beryllium, cadmium, chromium,

cyanide, fluoride, mercury, nickel, selenium, and thallium:  Section 611.603;

3)         Nitrate:  Section 611.604; and

4)         Nitrite:  Section 611.605.

BOARD NOTE:  Derived from 40 CFR

141.23(a) and (c).