Section 611.602 Asbestos 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 611.602 ASBESTOS MONITORING FREQUENCY

Section 611.602  Asbestos

Monitoring Frequency

The frequency of monitoring

conducted to determine compliance with the MCL for asbestos in Section 611.301

is as follows:

a)         Unless the Agency has determined under subsection (c) that the

PWS is not vulnerable, each CWS and NTNCWS supplier must monitor for asbestos

during the first compliance period of each compliance cycle.

b)         CWS suppliers may apply to the Agency, by way of an

application for a SEP, for a determination that the CWS is not vulnerable based

on consideration of the criteria listed in subsection (c).

c)         The Agency must determine that the CWS is "not

vulnerable" if the CWS is not vulnerable to contamination either from

asbestos in its source water, from corrosion of asbestos-cement pipe, or from

both, based on a consideration of the following factors:

1)         Potential asbestos contamination of the water source; and

2)         The use of asbestos-cement pipe for finished water

distribution and the corrosive nature of the water.

d)         A SEP based on a determination that a CWS is not vulnerable to

asbestos contamination expires at the end of the compliance cycle for which it

was issued.

e)         A supplier of a PWS vulnerable to asbestos contamination due

solely to corrosion of asbestos-cement pipe must take one sample at a tap

served by asbestos-cement pipe and under conditions that asbestos contamination

is most likely to occur.

f)         A supplier of a PWS vulnerable to asbestos contamination due

solely to source water must monitor in compliance with Section 611.601

d.

e)         A supplier of a PWS vulnerable to asbestos contamination due

solely to corrosion of asbestos-cement pipe must take one sample at a tap

served by asbestos-cement pipe and under conditions that asbestos contamination

is most likely to occur.

f)         A supplier of a PWS vulnerable to asbestos contamination due

solely to source water must monitor in compliance with Section 611.601.

g)         A supplier of a PWS vulnerable to asbestos contamination due

both to its source water supply and corrosion of asbestos-cement pipe must take

one sample at a tap served by asbestos-cement pipe and under conditions that

asbestos contamination is most likely to occur.

h)         A supplier that exceeds the MCL, as determined in Section

611.609, must monitor quarterly beginning in the next quarter after the

violation occurred.

i)          Reduction of Quarterly Monitoring

1)         The Agency must issue a SEP that reduces the monitoring

frequency to that specified by subsection (a) if it determines that the

sampling point is reliably and consistently below the MCL.

2)         The request must, at a minimum, include the following

information:

A)        For a GWS:  two quarterly samples.

B)        For an SWS or mixed system:  four quarterly samples.

3)         In issuing a SEP, the Agency must specify the level of the

contaminant upon which the "reliably and consistently" determination

was based.  All SEPs that allow less frequent monitoring based on an Agency

"reliably and consistently" determination must include a condition

requiring the supplier to resume quarterly monitoring under subsection (h) if

it violates the MCL specified by Section 611.609.

j)          This subsection (j) corresponds with 40 CFR 141.23(b)(10),

which pertains to a compliance period long since expired.  This statement

maintains structural consistency with the federal regulations.

BOARD NOTE:  Derived from 40 CFR

141.23(b).