Illinois Administrative Code › Title 35 - ENVIRONMENTAL PROTECTION › Part 611 - PRIMARY DRINKING WATER STANDARDS › Subpart W - INITIAL DISTRIBUTION SYSTEM EVALUATIONS › Section 611.922 - System-Specific Studies

Current through Register Vol. 48, No. 28, July 12, 2024
a)
				System-Specific Study Plan. A supplier's system-specific study plan must be
				based on either existing monitoring results, as required under subsection
				(a)(1), or modeling, as required under subsection (a)(2). The supplier must
				prepare and submit the supplier's system-specific study plan to the Agency
				according to the schedule in Section
				611.920(c).
1) Existing Monitoring Results. A supplier
				may comply by submitting monitoring results collected before it is required to
				begin monitoring under Section
				611.920(c).
				The monitoring results and analysis must meet the criteria in subsections
				(a)(1)(A) and (a)(1)(B).
A) Minimum
				Requirements
i) TTHM and HAA5 results must be
				based on samples collected and analyzed in accordance with Section
				611.381.
				Samples must be collected no earlier than five years prior to the study plan
				submission date.
ii) The monitoring
				locations and frequency must meet the conditions identified in the applicable
				of subsections (a)(1)(A)(iii) through (a)(1)(A)(xv). Each location must be
				sampled once during the peak historical month for TTHM levels or HAA5 levels or
				the month of warmest water temperature for every 12 months of data submitted
				for that location. Monitoring results must include all Subpart I compliance
				monitoring results, plus additional monitoring results as necessary to meet
				minimum sample requirements.
iii) A
				Subpart B system supplier that serves fewer than 500 persons must collect
				samples from three monitoring locations: three samples for TTHM and three
				samples for HAA5.
iv) A Subpart B
				system supplier that serves 500 to 3,300 persons must collect samples from
				three monitoring locations: nine samples for TTHM and nine samples for
				HAA5.
v) A Subpart B system
				supplier that serves 3,301 to 9,999 persons must collect samples from six
				monitoring locations: 36 samples for TTHM and 36 samples for HAA5.
vi) A Subpart B system supplier that serves
				10,000 to 49,999 persons must collect samples from each of 12 monitoring
				locations: 72 samples for TTHM and 72 samples for HAA5.
vii) A Subpart B system supplier that serves
				50,000 to 249,999 persons must collect samples from 24 monitoring locations:
				144 samples for TTHM and 144 samples for HAA5.
viii) A Subpart B system supplier that serves
				250,000 to 999,999 persons must collect samples from 36 monitoring locations:
				216 samples for TTHM and 216 samples for HAA5.
ix) A Subpart B system supplier that serves
				1,000,000 to 4,999,999 persons must collect samples from 48 monitoring
				locations: 288 samples for TTHM and 288 samples for HAA5.
x) A Subpart B system supplier that serves
				5,000,000 or more persons must collect samples from 60 monitoring locations:
				360 samples for TTHM and 360 samples for HAA5.
xi) A groundwater system supplier that serves
				fewer than 500 persons must collect samples from three monitoring locations:
				three samples for TTHM and three samples for HAA5.
xii) A groundwater system supplier that
				serves 500 to 9,999 persons must collect samples from three monitoring
				locations: nine samples for TTHM and nine samples for HAA5.
xiii) A groundwater system supplier that
				serves 10,000 to 99,999 persons must collect samples from 12 monitoring
				locations: 48 samples for TTHM and 48 samples for HAA5.
xiv) A groundwater system supplier that
				serves 100,000 to 499,999 persons must collect samples from 18 monitoring
				locations: 72 samples for TTHM and 72 samples for HAA5.
xv) A groundwater system supplier that serves
				500,000 or more persons must collect samples from 24 monitoring locations: 96
				samples for TTHM and 96 samples for HAA5.