Section 327IAC8-2-38. Monitoring requirements for water quality parameters

   (a) All:

(1) large water systems; and

(2) small and medium size water systems that exceed the lead or copper action level;

shall monitor water quality parameters in addition to lead and copper in accordance with this section. The requirements of this section are summarized in the table in subsection (b)(2)(A).

  (b) General monitoring requirements for water quality parameters shall be as follows:

(1) Requirements for sample collection methods shall be as follows:

(A) Tap samples shall be representative of water quality throughout the distribution system taking into account:

(i) the number of persons served;

(ii) the different sources of water;

(iii) the different treatment methods employed by the system; and

(iv) seasonal variability.

Tap sampling under this section is not required to be conducted at taps targeted for lead and copper sampling under section 37(a) of this rule. (Note: Systems may find it convenient to conduct tap sampling for water quality parameters at sites used for coliform sampling under section 8 of this rule.)

(B) Except as provided in subsection (d)(3), a system shall collect two (2) samples for each applicable water quality parameter at each entry point to the distribution system during each monitoring period specified in subsection (c). Samples collected at the entry point to the distribution system shall be from locations representative of each source after treatment. If a system draws water from more than one (1) source and the sources are combined before distribution, the system must sample at an entry point to the distribution system during periods of normal operating conditions, that is, when water used is representative of all sources being used.

(2) Requirements for the number of samples shall be as follows:

(A) Systems shall collect two (2) tap samples for applicable water quality parameters during each monitoring period specified under subsections (c) through (f) from the number of sites listed in the following table:

System Size (Number of People Served)	Number of Sites for Water Quality Parameters
> 100,000	25
10,001 to 100,000	10
3,301 to 10,000	3
501 to 3,300	2
101 to 500	1
< 101	1

(B) Systems shall collect two (2) samples for each applicable water quality parameter at each entry point to the distribution system during each monitoring period specified in subsection (c). During each monitoring period specified in subsections (d) through (f), systems shall collect one (1) sample for each applicable water quality parameter at each entry point to the distribution system.

  (c) This subsection governs initial sampling. All large water systems shall measure the applicable water quality parameters as specified in subdivision (1) at taps and at each entry point to the distribution system during each six (6) month monitoring period specified in section 37(d)(1) of this rule. All small and medium size systems shall measure the applicable water quality parameters at the locations specified in subdivision (1) during each six (6) month monitoring period specified in section 37(d)(1) of this rule during which the system exceeds the lead or copper action level. Monitoring requirements for water quality parameters at taps are as follows:

(1) The following are water quality parameters:

(A) pH.

(B) Alkalinity.

(C) Orthophosphate, when an inhibitor containing a phosphate compound is used.

(D) Silica, when an inhibitor containing a silica compound is used.

(E) Calcium.

(F) Conductivity.

(G) Water temperature.

(2) At each entry point to the distribution system, all of the applicable parameters listed in subdivision (1).

  (d) This subsection governs monitoring after installation of corrosion control. Any large system that installs corrosion control treatment under section 40(d)(4) of this rule shall measure the water quality parameters at the locations and frequencies specified in this subsection during each six (6) month monitoring period specified in section 37(d)(2)(A) of this rule. Any small or medium size system that installs corrosion control treatment shall conduct monitoring during each six (6) month monitoring period specified in section 37(d)(2)(B) of this rule in which the system exceeds the lead or copper action level. Monitoring requirements for water quality parameters at taps are as follows:

(1) The water quality parameters at taps require two (2) samples for the following:

(A) pH.

(B) Alkalinity.

(C) Orthophosphate, when an inhibitor containing a phosphate compound is used.

(D) Silica, when an inhibitor containing a silicate compound is used.

(E) Calcium, when calcium carbonate stabilization is used as part of corrosion control.

(2) Except as provided in subdivision (3), at each entry point to the distribution system are one (1) sample not less frequently than every two (2) weeks (biweekly) for the following:

(A) pH.

(B) When alkalinity is adjusted as part of optimal corrosion control, a reading of the dosage rate of the chemical used to adjust alkalinity and the alkalinity concentration.

(C) When a corrosion inhibitor is used as part of optimal corrosion control, a reading of the dosage rate of the inhibitor used and the concentration of the orthophosphate or silica, whichever is applicable.

(3) A ground water system may limit entry point sampling described in subdivision (2) to those entry points that are representative of water quality and treatment conditions throughout the system. If water from untreated ground water sources mixes with water from treated ground water sources, the system must monitor for water quality parameters both at representative entry points receiving treatment and representative entry points receiving no treatment. Prior to the start of any monitoring under this subdivision, the system shall provide to the commissioner written information identifying the selected entry points and documentation, including information on seasonal variability, sufficient to demonstrate that the sites are representative of water quality and treatment conditions throughout the system.

  (e) This subsection governs monitoring after water quality parameter values for optimal corrosion control are specified. After the commissioner specifies the values for applicable water quality control parameters reflecting optimal corrosion control treatment under section 41(f) of this rule, the following systems shall comply as follows:

(1) Large water systems shall:

(A) measure the applicable water quality parameters in accordance with subsection (d); and

(B) determine compliance with the requirements of section 42(g) of this rule every six (6) months with the first six (6) month period to begin on either January 1 or July 1, whichever comes first after the commissioner specifies the optimal values under section 41(f) of this rule.

(2) Any small or medium size system:

(A) shall conduct monitoring for the applicable water quality parameters during each six (6) month period in which the system exceeds the lead or copper action level; and

(B) that is subject to a reduced monitoring frequency under section 37(d)(4) of this rule at the time of the action level exceedance, shall start the applicable six (6) month monitoring period to coincide with the start of the applicable monitoring period under section 37(d)(4) of this rule.

Compliance with commissioner-designated optimal water quality parameter values shall be determined as specified under section 41(g) of this rule.

  (f) The following are requirements for reduced monitoring:

(1) Any water system that maintains the range of values for the water quality parameters reflecting optimal corrosion control treatment during each of two (2) consecutive six (6) month monitoring periods under subsection (e) shall continue monitoring at the entry point to the distribution system as specified in subsection (d)(2). The system may collect two (2) tap samples for applicable water quality parameters from the reduced number of sites shown in the following table during each six (6) month monitoring period:

System Size (Number of People Served)	Reduced Number of Sites of Water Quality Parameters
> 100,000	10
10,001 to 100,000	7
3,301 to 10,000	3
501 to 3,300	2
101 to 500	1
< 101	1

(2) This subdivision designates reduced monitoring requirements for water quality parameters as follows:

(A) Any water system that maintains the range of values for water quality parameters reflecting optimal corrosion control treatment specified by the commissioner under section 41(f) of this rule during three (3) consecutive years of monitoring may reduce the frequency with which it collects the number of tap samples specified in subdivision (1) for applicable water quality parameters from once every six (6) months to annually. This sampling begins during the calendar year immediately following the end of the monitoring period in which the third consecutive year of six (6) month monitoring occurs. Any water system that maintains the range of water quality parameters reflecting optimal corrosion control treatment specified by the commissioner under section 41(f) of this rule during three (3) consecutive years of annual monitoring under this subdivision may reduce the frequency with which it collects the number of tap samples for applicable water quality parameters specified in subdivision (1) from annually to once every three (3) years. This sampling begins not later than the third calendar year following the end of the monitoring period in which the third consecutive year of monitoring occurs.

(B) A water system may reduce the frequency of collecting tap samples to every three (3) years for applicable water quality parameters specified in subsection (d)(1) if the system demonstrates the following during two (2) consecutive monitoring periods:

(i) The system's tap water lead level at the ninetieth percentile is less than or equal to the PQL for lead as specified in section 45(b)(2) of this rule.

(ii) The system's tap water copper level at the ninetieth percentile is less than or equal to sixty-five hundredths (0.65) milligram per liter (mg/L) for copper as specified in section 36(c)(2) of this rule.

(iii) The system has maintained the range of values for the water quality parameters reflecting optimal corrosion control treatment specified by the commissioner under section 41(f) of this rule.

Monitoring done every three (3) years must be done not later than every third calendar year.

(3) A water system that conducts sampling annually shall collect these samples evenly throughout the year so as to reflect seasonal variability.

(4) Any water system subject to the reduced monitoring frequency that fails to operate at or above the minimum value or within the range of values for the water quality parameters specified by the commissioner under section 41(f) of this rule for more than nine (9) days in any six (6) month monitoring period shall resume distribution tap water sampling in accordance with the number and frequency requirements in subsection (e). The system may resume:

(A) annual monitoring for water quality parameters number of sites specified in subdivision (2) after it has completed two (2) subsequent consecutive six (6) month rounds of monitoring that meet the criteria of that subsection; or

(B) triennial monitoring for water quality parameters at the tap at the reduced number of sites after it demonstrates that it meets the criteria of either subdivision (2)(A) or (2)(B).

  (g) The results of any monitoring conducted in addition to the minimum requirements of this section shall be considered by the system and the commissioner in making any determinations, for example, determining concentrations of water quality parameters under this section or section 41 of this rule. (Water Pollution Control Division; 327 IAC 8-2-38; filed Aug 24, 1994, 8:15 a.m.: 18 IR 71; errata filed Oct 11, 1994, 2:45 p.m.: 18 IR 532; filed Oct 24, 1997, 4:30 p.m.: 21 IR 940; filed Oct 26, 2001, 4:55 p.m.: 25 IR 770; errata filed Oct 30, 2001, 10:50 a.m.: 25 IR 813; errata filed Feb 22, 2002, 1:59 p.m.: 25 IR 2254; filed May 7, 2010, 9:30 a.m.: 20100602-IR-327080198FRA)