Current through August 26, 2024
(1) INITIAL ROUND
OF SOURCE WATER MONITORING. Water suppliers shall have conducted the following
monitoring according to the schedule in sub. (3) Table H, at treatment plants
existing as of January 5, 2006 unless the public water system meets the
monitoring exemption criteria in sub. (4). The initial source water monitoring
requirements were conducted under 40 CFR part 141 National Primary Drinking
Water Regulations Subpart W with EPA wholly responsible for implementation. For
public water systems with treatment plants constructed after January 5, 2006
the department may require the following initial monitoring as part of the
approval process under s.
NR 811.21(1)
(f).
(a)
Water suppliers for filtered public water systems serving at least 10,000
people shall sample their source water for Cryptosporidium, E. coli, and
turbidity at least monthly for 24 months.
(b) Water suppliers for unfiltered public
water systems serving at least 10,000 people shall sample their source water
for Cryptosporidium at least monthly for 24 months.
(c) Water suppliers for filtered public water
systems serving fewer than 10,000 people shall sample their source water for E.
coli at least once every two weeks for 12 months. A filtered public water
system serving fewer than 10,000 people may avoid E. coli monitoring if the
water supplier notifies the department that Cryptosporidium will be monitored
for as described in sub. (3). The water supplier shall notify the department no
later than 3 months prior to the date the public water system is required to
start E. coli monitoring under sub. (3).
(d) Water suppliers for filtered public water
systems serving fewer than 10,000 people shall sample their source water for
Cryptosporidium at least twice per month for 12 months or at least monthly for
24 months if based on monitoring conducted under par. (c), and if they meet one
of the following:
1. For public water systems
using lake or reservoir sources, the annual mean E. coli concentration is
greater than 10 E. coli /100 mL.
2.
For public water systems using flowing stream sources, the annual mean E. coli
concentration is greater than 50 E. coli /100 mL.
3. The public water system was not monitored
for E. coli as described in par. (c).
4. Public water systems using groundwater
under the direct influence of surface water (GWUDI) shall comply with the
requirements of this paragraph based on the E. coli level that applies to the
nearest surface water body. If no surface water body is nearby, the public
water system shall comply based on the requirements that apply to public water
systems using lake or reservoir sources.
(e) For filtered public water systems serving
fewer than 10,000 people, the department may approve monitoring for an
indicator other than E. coli under par. (c). The department also may approve an
alternative to the E. coli concentration in par. (d) 1. to 3. to trigger
Cryptosporidium monitoring. This approval by the department shall be provided
to the public water system in writing and shall include the basis for the
department's determination that the alternative indicator or trigger level will
provide a more accurate identification of whether a public water system will
exceed the Bin 1 Cryptosporidium level in s.
NR 810.34.
(f) Water suppliers for unfiltered public
water systems serving fewer than 10,000 people shall sample their source water
for Cryptosporidium at least twice per month for 12 months or at least monthly
for 24 months.
(g) Water suppliers
may sample more frequently than required under this section if the sampling
frequency is evenly spaced throughout the monitoring period.
(2) SECOND ROUND OF SOURCE WATER
MONITORING. Water supplier shall conduct a second round of source water
monitoring that meets the requirements for monitoring parameters, frequency,
and duration described in sub. (1), unless they meet the monitoring exemption
criteria in sub. (4). Water suppliers shall conduct this monitoring on the
schedule in sub. (3).
(3)
MONITORING SCHEDULE. According to EPA requirements, water supplier shall begin
the monitoring required in subs. (1) and (2) no later than the month beginning
with the date listed in Table H:
TABLE H
Source Water Monitoring Starting Dates
|
Public water systems that serve . . .
|
The initial round of source water monitoring
shall begin no later than the month beginning:
|
The second round of source water monitoring
shall begin no later than the month beginning:
|
| (1) At least 100,000 people |
October 1, 2006 |
April 1, 2015 |
| (2) From 50,000 to 99,999 people |
April 1, 2007 |
October 1, 2015 |
| (3) From 10,000 to 49,999 people |
April 1, 2008 |
October 1, 2016 |
| (4) Fewer than 10,000 and monitor for E.
coli1
|
October 1, 2008 |
October 1, 2017 |
| (5) Fewer than 10,000 and monitor for
Cryptosporidium
2
|
April 1, 2010 |
April 1, 2019 |
1 Applies only to filtered public water systems.
2 Applies to filtered public water systems that meet the
conditions of sub. (1) (e) and unfiltered public water systems.
(4) MONITORING AVOIDANCE.
(a) Water suppliers for filtered public water
systems are not required to conduct source water monitoring under this section
if the public water 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 s.
NR 810.35.
(b) Water supplier for unfiltered public
water systems are not required to conduct source water monitoring under this
section if the public water system will provide a total of at least 3-log
Cryptosporidium inactivation, equivalent to meeting the treatment requirements
for unfiltered public water systems with a mean Cryptosporidium concentration
of greater than 0.01 oocysts/L in s.
NR 810.36.
(c) If a water supplier chooses to provide
the level of treatment in par. (a) or (b), as applicable, rather than start
source water monitoring, the water supplier shall notify the department in
writing no later than the date the public water system is otherwise required to
submit a sampling schedule for monitoring under s.
NR 809.332. Alternatively, a water supplier may choose to
stop sampling at any point after the public water system has initiated
monitoring if the water supplier notifies the department in writing that the
public water system will provide this level of treatment. Water supplier shall
install and operate technologies to provide this level of treatment by the
applicable treatment compliance date in s.
NR 810.37.
(5) PLANTS OPERATING ONLY PART OF THE YEAR.
Water suppliers for public water systems with surface water treatment plants
that operate for only part of the year shall conduct source water monitoring in
accordance with this section, but with the following modifications:
(a) Water supplier shall sample their source
water only during the months that the plant operates unless the department
specifies another monitoring period based on plant operating
practices.
(b) Water supplier for
public water systems with plants that operate less than six months per year and
that monitor for Cryptosporidium shall collect at least six Cryptosporidium
samples per year during each of two years of monitoring. Samples shall be
evenly spaced throughout the period the plant operates.
(6) NEW SOURCES.
(a) A water supplier for a public water
system that begins using a new source of surface water or GWUDI after the
public water system is required to begin monitoring under sub. (3) shall
monitor the new source on a schedule the department approves. Source water
monitoring shall meet the requirements of this section. The public water system
shall also meet the bin classification and Cryptosporidium treatment
requirements of ss.
NR 810.34 and 810.35 or s.
NR 810.36, as applicable, for the new source on a
schedule the department approves.
(b) The requirements of this section apply to
public water systems with surface water treatment plants that begin operation
after the monitoring start date applicable to the public water system's size
under sub. (3).
(c) The water
supplier shall begin a second round of source water monitoring no later than 6
years following initial bin classification under s.
NR 810.34 or determination of the mean Cryptosporidium
level under s.
NR 810.36, as applicable.
(7) MONITORING VIOLATION. Failure to collect
any source water sample required under this section in accordance with the
sampling schedule, sampling location, analytical method, approved laboratory,
and reporting requirements of s. NR 809. 332 to s.
NR 809.336 is a monitoring violation.
(8) GRANDFATHERING MONITORING DATA. The water
supplier may use monitoring data collected prior to the applicable monitoring
start date in sub. (3) to meet the initial source water monitoring requirements
in sub. (1). This data, referred to as grandfathered data, may substitute for
an equivalent number of months of data at the end of the monitoring period. All
data submitted under this section shall meet the requirements in s.
NR 809.334.
