35 Ill. Adm. Code 6110.611.1001
Source Water Monitoring Requirements: Source Water Monitoring
TITLE 35: ENVIRONMENTAL PROTECTION
SUBTITLE F: PUBLIC WATER SUPPLIES
CHAPTER I: POLLUTION CONTROL BOARD
PART 611 PRIMARY DRINKING WATER STANDARDS
SECTION 611.1001 SOURCE WATER MONITORING REQUIREMENTS: SOURCE WATER MONITORING
Section 611.1001 Source Water Monitoring Requirements:
Source Water Monitoring
a) Initial
Round of Source Water Monitoring. A supplier must conduct the following
monitoring on the schedule in subsection (c), unless it meets the monitoring exemption
criteria in subsection (d).
1) A
filtered system supplier serving 10,000 or more people must sample its source
water for Cryptosporidium, E. coli, and turbidity at least monthly for 24
months.
2) An
unfiltered system supplier serving 10,000 or more people must sample its source
water for Cryptosporidium at least monthly for 24 months.
3) Smaller
System Suppliers Monitoring for E. coli
A) A
filtered system supplier serving fewer than 10,000 people must sample its
source water for E. coli at least once every two weeks for 12 months.
B) A
filtered system supplier serving fewer than 10,000 people may avoid E. coli
monitoring if the system notifies the Agency that it will monitor for
Cryptosporidium as described in subsection (a)(4). The system must notify the
Agency no later than three months prior to the date before which the system is
otherwise required to start E. coli monitoring under subsection (c).
4) Smaller
System Suppliers Monitoring for Cryptosporidium. A filtered system supplier serving
fewer than 10,000 people must sample its source water for Cryptosporidium at
least twice per month for 12 months or at least monthly for 24 months if it
meets any of the conditions in subsections (a)(4)(A) through (a)(4)(C), subject
to the limitations of subsection (a)(4)(D), based on monitoring conducted under
subsection (a)(3).
A) For a
supplier using a lake or reservoir source, the annual mean E. coli
concentration is greater than 10 E. coli/100 mL.
B) For a
supplier using a flowing stream source, the annual mean E. coli concentration
is greater than 50 E. coli/100 mL.
C) The
supplier does not conduct E. coli monitoring as described in subsection (a)(3).
D) A
supplier using groundwater under the direct influence of surface water must
comply with the requirements of subsection (a)(4) based on the E. coli level
that applies to the nearest surface water body. If no surface water body is
nearby, the system must comply based on the requirements that apply to a
supplier using a lake or reservoir source.
5) For a
filtered system supplier serving fewer than 10,000 people, the Agency may issue
a SEP approving monitoring for an indicator other than E. coli under subsection
(a)(3). The Agency may also issue a SEP approving an alternative to the E.
coli concentration in subsection (a)(4)(A), (a)(4)(B), or (a)(4)(D) to trigger
Cryptosporidium monitoring. This approval by the Agency must be provided to
the supplier in writing, and it must include the basis for the Agency's determination
that the alternative indicator or trigger level will provide a more accurate
identification of whether a system will exceed the Bin 1 Cryptosporidium level
in Section 611.1010.
6) An
unfiltered system supplier serving fewer than 10,000 people must sample its
source water for Cryptosporidium at least twice per month for 12 months or at
least monthly for 24 months.
7) A
supplier may sample more frequently than required by this Section if the
sampling frequency is evenly spaced throughout the monitoring period.
b) Second
Round of Source Water Monitoring. A supplier must conduct a second round of
source water monitoring that meets the requirements for monitoring parameters,
frequency, and duration described in subsection (a), unless it meets the monitoring
exemption criteria in subsection (d). The supplier must conduct this
monitoring on the schedule in subsection (c).
c) Monitoring
Schedule. A supplier must perform the two rounds of monitoring subsections (a)
and (b) require on the schedule in this subsection (c), unless the supplier
meets the monitoring exemption criteria in subsection (d).
1) Suppliers
That Serve at Least 100,000 People
A) The
suppliers must have begun the first round of source water monitoring no later
than the end of October 2006.
B) The
suppliers must have begun the second round of source water monitoring no later
than the end of April 2015.
2) Suppliers
That Serve
from 50,000 to 99,999 People
A) The
suppliers must have begun the first round of source water monitoring no later
than the end of April 2007.
B) The
suppliers must have begun the second round of source water monitoring no later
than the end of October 2015.
3) Suppliers
That Serve from 10,000 to 49,999 People
A) The
suppliers must have begun the first round of source water monitoring no later
than the end of April 2008.
B) The
suppliers must have begun the second round of source water monitoring no later
than the end of October 2016.
4) Suppliers
That Serve Fewer Than 10,000 People and That Monitor for E. coli
A) The
suppliers must have begun the first round of source water monitoring no later
than the end of October 2008.
B) The
suppliers must have begun the second round of source water monitoring no later
than the end of October 2017.
5) Suppliers
That Serve Fewer Than 10,000 People and That Monitor for Cryptosporidium
A) The
suppliers must have begun the first round of source water monitoring no later
than the end of April 2010.
B) The
suppliers must have begun the second round of source water monitoring no later
than the end of April 2019.
BOARD NOTE: The Board retained
the past implementation dates until implementation of the Long Term 2 Enhanced
Surface Water Treatment Rule in this Subpart Z is complete.
d) Monitoring
Avoidance
1) A
filtered system supplier is not required to conduct source water monitoring under
this Subpart Z if the system will provide a total of at least 5.5-log of
treatment for Cryptosporidium, equivalent to meeting the treatment requirements
of Bin 4 in Section 611.1011.
2) An
unfiltered system supplier is not required to conduct source water monitoring under
this Subpart Z if the system will provide a total of at least 3-log
Cryptosporidium inactivation, equivalent to meeting the treatment requirements
for an unfiltered system supplier with a mean Cryptosporidium concentration of
greater than 0.01 oocysts/L in Section 611.1012.
3) If a
supplier chooses to provide the level of treatment in subsection (d)(1) or
(d)(2), as applicable, rather than start source water monitoring, it must
notify the Agency in writing no later than the date on which the system is
otherwise required to submit a sampling schedule for monitoring under Section
611.1002. Alternatively, a supplier may choose to stop sampling at any point
after it has initiated monitoring if it notifies the Agency in writing that it
will provide this level of treatment. The supplier must install and operate
technologies to provide this level of treatment before the applicable treatment
compliance date in Section 611.1013.
e) Plants
Operating Only Part of the Year. A supplier that has a Subpart B plant that
operates for only part of the year must conduct source water monitoring in compliance
with this Subpart Z, but with the following modifications:
1) The
supplier must sample its source water only during the months that the plant
operates, unless the Agency issue a SEP specifying another monitoring period
based on plant operating practices.
2) A
supplier with plants that operate less than six months per year and that monitors
for Cryptosporidium must collect at least six Cryptosporidium samples per year
during each of two years of monitoring. Samples must be evenly spaced
throughout the period during which the plant operates.
f) New Sources
and New Systems
1) New
sources. A supplier that begins using a new source of surface water or
groundwater under the direct influence of surface water after the supplier was
required to begin monitoring under subsection (c) must monitor the new source
on a schedule that the Agency has approved in a SEP. Source water monitoring
must meet the requirements of this Subpart Z. The supplier must also meet the
bin classification and Cryptosporidium treatment requirements of Sections
611.1010 and 611.1011 or Section 611.1012, as applicable, for the new source on
a schedule that the Agency has approved in a SEP.
2) The
requirements of Section 611.1001(f) apply to a Subpart B system supplier that
begins operation after the applicable monitoring start date in subsection (c).
3) The
supplier must begin a second round of source water monitoring no later than six
years following initial bin classification under Section 611.1010 or
determination of the mean Cryptosporidium level under Section 611.1012.
g) Failure
to collect any source water sample required under this Section in compliance
with the sampling schedule, sampling location, analytical method, approved
laboratory, and reporting requirements of Sections 611.1002 through 611.1006 is
a monitoring violation.
h) Grandfathering
Monitoring Data. A supplier may use (grandfather) monitoring data collected
prior to the applicable monitoring start date in subsection (c) to meet the
initial source water monitoring requirements in subsection (a). Grandfathered
data may substitute for an equivalent number of months at the end of the
monitoring period. All data submitted under this subsection must meet the
requirements in Section 611.1007.
BOARD NOTE: This Section derives from 40 CFR 141.701.