35 Ill. Adm. Code 6110.611.358
Monitoring for Lead and Copper in Source Water
Section 611
TITLE 35: ENVIRONMENTAL PROTECTION
SUBTITLE F: PUBLIC WATER SUPPLIES
CHAPTER I: POLLUTION CONTROL BOARD
PART 611 PRIMARY DRINKING WATER STANDARDS
SECTION 611.358 MONITORING FOR LEAD AND COPPER IN SOURCE WATER
Section 611.358 Monitoring
for Lead and Copper in Source Water
a) Sampling Location, Collection Methods, and Number of Samples
1) A supplier failing to meet the lead or copper action level on
the basis of tap samples under Section 611.356 must collect lead and copper
source water samples under specific requirements for sample location, number of
samples, and collection methods:
A) A groundwater supplier must take a minimum of one sample at
every entry point to the distribution system after the supplier applies any
treatment or in the distribution system at a point representing each source
after treatment (a "sampling point"). The supplier must take one
sample at the same sampling point unless conditions make another sampling point
more closely represent a source or treatment plant.
B) A surface water supplier must take a minimum of one sample at
every entry point to the distribution system after treatment or in the
distribution system at a sampling point. The supplier must take each sample at
the same sampling point unless conditions make another sampling point more closely
represent a source or treatment plant.
BOARD NOTE:
For this subsection (a)(1)(B), a system using a combination of surface water
and groundwater sources is a surface water system.
C) If a supplier draws water from more than one source and combines
the sources before distribution, the supplier must sample at an entry point to the
distribution system during periods of normal operating conditions (i.e., when
water represents all sources being used).
D) The Agency may issue a SEP reducing the total number of samples
a supplier must analyze by allowing the use of compositing. Certified
laboratory personnel must composite the samples. A composite sample may
include a maximum of five samples. However, if the lead concentration in the
composite sample is greater than or equal to 0.001 mg/L or the copper
concentration is greater than or equal to 0.160 mg/L, the supplier must do
either of two things:
i) The supplier must take and analyze a follow-up sample within
14 days at each sampling point included in the composite sample; or
ii) If duplicate samples or sufficient volumes of the original
samples are available from each sampling point the certified laboratory used in
the composite sample, the supplier may use those instead of resampling.
2) SEP Requiring an Additional Sample
A) Upon determining that sampling indicates exceedance of the lead
or copper MPC under Section 611.353(b)(4), the Agency must issue a SEP
requiring the supplier to collect one additional sample as soon as possible
after the initial sample at the same sampling point but before two weeks after
the supplier took the initial sample.
B) If a supplier takes an Agency-required confirmation sample for
lead or copper, the supplier must average the results obtained from the initial
sample with those from the confirmation sample to determine whether it complies
with the Agency-specified lead and copper MPCs.
i) For averaging, consider any analytical result below the MDL
as zero.
ii) Consider any value above the MDL but below the PQL either as
the measured value or one-half the PQL.
b) Monitoring
Frequency after System Exceeds Tap Water Action Level. A supplier exceeding
the lead or copper action level in tap for the first time or for the first time
after adding a new source or installing source water treatment under Section
611.353(b)(2) must collect one source water sample from each entry point to its
distribution system no later than six months after the end of the tap sampling
period during which the supplier exceeds the lead or copper action level. For annual
or less frequent tap monitoring period, the end of the tap sampling period is
September 30 of the calendar year during which the sampling occurs or the last
day of any alternative tap sampling period the Agency establishes in a SEP. If
the Agency
determines under
Section 611.353(b)(2) that source water treatment is not
necessary,
the Agency may issue a SEP waiving source water monitoring
for the supplier subsequently
exceeding the lead or copper action level at the tap
under
subsections (b)(1)(A) through (b)(1)(C)
.
1) The
Agency may issue a SEP waiving source water monitoring
for
the supplier exceeding the lead or copper action level at the tap
under specific conditions
:
A) T
he supplier already conducted
source water monitoring
after previously exceeding the lead or copper action level
;
B) T
he Agency issued a SEP determin
ing that source water
treatment is not necessary
; and
C) The
supplier has not added any new water sources.
2) This
subsection (b)(2) corresponds with 40 CFR 141.88(b)(2), which USEPA marked "[reserved]".
This statement maintains structural consistency with USEPA's rule.
c) Monitoring Frequency after Installing Source Water Treatment
or Adding a New Source
1) A supplier installing source water treatment under Section
611.353(a)(3) must collect one source water sample from each entry point to its
distribution system during each of two consecutive six-month source water monitoring
periods on or before 36 months after completing step 2, as Section
611.353(a)(4) specifies.
2)
A
supplier adding a
new source must collect
one source water sample from each
entry point to its distribution system
during each six-month source
water monitoring period
until the supplier demonstrates
that the supplier
has
maintained finished drinking water entering the distribution system below
the MPCs for lead and copper
the Agency specifies under Section 611.353(b)(4)
,
or the Agency issues a SEP determining that the supplier
does not need source water treatment
.
d) Monitoring Frequency after the Agency Specifies the Lead and Copper
MPCs
1) A supplier must monitor at the frequency subsections (d)(1)
and (d)(2) specify if the Agency specifies the MPCs under Section
611.353(b)(4).
A) GWS Suppliers
i) A GWS supplier sampling under subsection (d)(1) must collect
samples once during the three-year compliance period (as Section 611.101
defines the term) during which the Agency makes its determination under Section
611.353(b)(4).
ii) A GWS supplier sampling under subsection (d)(1) must sample
once during each subsequent compliance period.
iii) A supplier must triennially collect samples every third
calendar year.
B) A SWS or mixed system supplier must collect samples once during
each calendar year, the first annual source water monitoring period to begin during
the year in which the Agency makes its determination under Section
611.353(b)(4).
2) A supplier needs not sample source water for lead or copper if
the supplier meets the action level for the specific contaminant in all tap
water samples during the entire source water monitoring period under subsection
(d)(1)(A) or (d)(1)(B).
e) Reduced Monitoring Frequency
1) A GWS supplier may reduce its source water monitoring
frequency for lead and copper to once during each nine-year compliance cycle
(as Section 611.101 defines the term) if the supplier collects the samples
every ninth calendar year, and only if the supplier meets certain criteria:
A) The supplier demonstrates that finished drinking water entering
the distribution system remains below the MPCs for lead and copper the Agency
specifies under Section 611.353(b)(4) during at least three consecutive monitoring
periods under subsection (d)(1).
B)
This subsection (e)(1)(B) corresponds
with 40 CFR 141.88(e)(1)(ii), which USEPA marked "[reserved]". This
statement maintains structural consistency with USEPA's rule.
2) A SWS or mixed system supplier may reduce its monitoring
frequency subsection (d)(1) requires to once during each nine-year compliance
cycle (as Section 611.101 defines the term) if the supplier collects the
samples every ninth calendar year, and only if the supplier meets certain
criteria:
A) The supplier demonstrates that finished drinking water entering
its distribution system remains below the MPCs for lead and copper the Agency
specifies under Section 611.353(b)(4) for at least three consecutive years.
B) This subsection (e)(2)(B) corresponds with 40 CFR 141.88(e)(2)(ii),
which USEPA marked "[reserved]". This statement maintains structural
consistency with USEPA's rule.
3) A supplier using a new source of water must not reduce its
monitoring for lead or copper until after the supplier demonstrates, by samples
it collected from the new source during three consecutive source water monitoring
periods under subsection (d)(1), that lead or copper levels are below the MPC
the Agency specifies under Section 611.353(a)(5).
BOARD NOTE: This
Section derives from 40 CFR 141.88.