5 Colo. Code Regs. § 1002-11.19

Current through Register Vol. 47, No. 20, October 25, 2024

Section 5 CCR 1002-11.19 - INORGANIC CHEMICALS RULE

11.19(1) Applicability and Definitions

(a) For all community and non-transient, non-community water systems, the supplier must comply with the requirements specified in this rule.

(i) For non-transient, non-community water systems, the supplier is required to comply with the sampling requirements for fluoride but is not required to comply with the fluoride MCL unless the Department determines that complying with the MCL is necessary to protect public health.

(ii) For transient, non-community water systems, the supplier may be required to comply with the fluoride MCL if the Department determines that complying with the MCL is necessary to protect public health.

(b) For the purpose of this rule, "INORGANIC CHEMICALS" means all the chemicals listed in Table 11.19-I.

11.19(2)MCL Requirements for Inorganic Chemicals

(a) The inorganic chemical MCLs are as follows:

TABLE 11.19-I INORGANIC CHEMICAL MCLs
Chemical	MCL (mg/L)
Antimony	0.006
Arsenic	0.010
Asbestos	7 Million Fibers/liter (Longer than 10 µm)
Barium	2
Beryllium	0.004
Cadmium	0.005
Chromium	0.1
Cyanide (as free Cyanide)	0.2
Fluoride	4.01
Mercury	0.002
Nickel	N/A2
Selenium	0.05
Thallium	0.002

1 This is the primary MCL for fluoride. Fluoride also has a secondary MCL of 2.0 mg/L.

2 Nickel has no MCL. The supplier must sample for nickel as specified in 11.19(3)(b).

(b) The cited detection limits for inorganic chemical analysis are specified in 40 CFR 141.23(a)(4)(i).

(c) The BATs for achieving compliance with the MCLs for inorganic chemicals, with the exception of fluoride, are specified in 40 CFR 141.62(c).

(d) For systems supplying less than or equal to ([LESS THAN EQUAL TO]) 10,000 people, the SSCTs for achieving compliance with the MCL for arsenic are specified in 40 CFR 141.62(d).

11.19(3)Sampling Requirements for Inorganic Chemicals

(a)General Sampling Requirements for Inorganic Chemicals

(i) To determine compliance with the MCLs for inorganic chemicals, the supplier must comply with the sampling requirements specified in this section, 11.19(3).

(ii) The supplier may apply to the Department to sample more frequently than required.

(iii) The Department may:

(A) Require the supplier to sample more frequently than the minimum requirements specified in this section, 11.19(3).

(B) Require the supplier to collect a confirmation sample for any sample result.

(C) Invalidate sample results based on sampling or analytical errors.

(D) Specify when the supplier must sample during each monitoring period.

(iv) If the system draws water from more than one source and the sources are combined before distribution, the supplier must sample during periods of normal operating conditions.

(b)Sampling Requirements for Antimony, Arsenic, Barium, Beryllium, Cadmium, Chromium, Cyanide, Fluoride, Mercury, Nickel, Selenium and Thallium

(i) To determine compliance with the MCLs for antimony, arsenic, barium, beryllium, cadmium, chromium, cyanide, fluoride, mercury, selenium and thallium, the supplier must comply with the sampling requirements specified in this section, 11.19(3)(b).

(A) For nickel, the supplier must comply with the sampling requirements specified in this section, 11.19(3)(b), and the requirements specified in 11.19(3)(a).

(ii) For new systems, new sources, or reclassified systems that now meet the applicability of this rule, the Department shall specify the initial sampling frequency at each entry point. The supplier must demonstrate compliance with the MCLs no later than one year after beginning supplying water to the public or one year after being reclassified.

(iii) After completing initial sampling, if the Department requires the supplier to sample at a routine frequency, the supplier must collect one sample at each entry point:

(A) For surface water systems, annually.

(B) For groundwater systems, once during each three-year compliance period.

(iv) The Department may allow the supplier to reduce the sampling frequency based on all of the following information:

(A) All previous sample results.

(B) The degree of variation in previous sample results.

(C) Other factors which may affect chemical concentrations (e.g., changes in groundwater pumping rates, the system's configuration, the system's operating procedures, or stream flows or characteristics).

(v) If any sample result is greater than (>) the MCL, the supplier must collect a confirmation sample at that entry point as soon as possible, but no later than 14 days after the original sample was collected.

(vi) If the average of any sample result and its confirmation sample result is greater than (>) the MCL, the supplier must increase the sampling frequency to quarterly at that entry point.

(A) The Department may allow the supplier to return to a routine sampling frequency at that entry point if the Department determines that the sample results are reliably and consistently below the MCL. To make that determination, the supplier must collect:

(I) For surface water systems, at least four quarters of samples at the entry point where the exceedance occurred.

(II) For groundwater systems, at least two quarters of samples at the entry point where the exceedance occurred.

(c)Sampling Waiver Requirements for Antimony, Arsenic, Barium, Beryllium, Cadmium, Chromium, Cyanide, Fluoride, Mercury, Nickel, Selenium and Thallium

(i) The supplier may apply to the Department or the Department may initiate a sampling waiver from antimony, arsenic, barium, beryllium, cadmium, chromium, cyanide, fluoride, mercury, nickel, selenium and thallium.

(ii) If the Department grants a waiver, the supplier is not required to sample at the frequencies specified in 11.19(3)(b).

(iii) The Department may grant a waiver to the supplier if all previous sample results are reliably and consistently below the MCL. To make that determination, the supplier must have collected:

(A) For surface water systems, annual samples for at least three years.

(B) For groundwater systems, samples for at least three consecutive three-year compliance periods.

(C) For a new source, samples for at least three monitoring periods.

(iv) For a cyanide waiver, the supplier must only demonstrate that the system is not vulnerable to cyanide based on the lack of any industrial source of cyanide.

(v) If the supplier is granted a waiver, the waiver will be effective for no more than one nine-year compliance cycle. The supplier must collect at least one sample while the waiver is effective.

(vi) When the supplier submits new sample results, or when other relevant data are available, the Department may revise the required sampling frequency.

(d)Sampling Requirements for Asbestos

(i) To determine compliance with the MCL for asbestos, the supplier must comply with the sampling requirements specified in this section, 11.19(3)(d).

(ii) For new systems, new sources, or reclassified systems that now meet the applicability of this rule, the supplier must begin sampling at a routine frequency when the new system or source begins supplying water to the public or when the system is reclassified.

(iii) For routine sampling, the supplier must collect one sample during the first three-year compliance period of each nine-year compliance cycle at the following locations:

(A) For systems that are vulnerable to asbestos from corrosion of asbestos-cement pipe, at taps that are supplied by asbestos-cement pipe under conditions where asbestos contamination is most likely to occur.

(B) For systems that are vulnerable to asbestos from source water contamination, at each entry point.

(C) For systems that are vulnerable to asbestos from both corrosion of asbestos-cement pipe and source water contamination, at taps that are supplied by asbestos-cement pipe under conditions where asbestos contamination is most likely to occur.

(iv) If any sample result is greater than (>) the MCL, the supplier must collect a confirmation sample at that sampling location no later than 14 days after the original sample was collected.

(v) If the average of any sample result and its confirmation sample result is greater than (>) the MCL, the supplier must increase the sampling frequency at that sampling location to quarterly.

(A) The Department may allow the supplier to return to routine sampling if the Department determines the sample results at that sampling location are reliably and consistently below the MCL. To make that determination, the supplier must collect:

(I) For surface water systems, at least four quarters of samples at the sampling location where the exceedance occurred.

(II) For groundwater systems, at least two quarters of samples at the sampling location where the exceedance occurred.

(e)Sampling Waiver Requirements for Asbestos

(i) The supplier may apply to the Department for an asbestos waiver or the Department may initiate an asbestos waiver.

(ii) The Department may grant a waiver to the supplier if the system is not vulnerable to potential asbestos contamination based on all of the following information:

(A) Potential asbestos contamination of the source water.

(B) The use of asbestos-cement pipe in the distribution system and the corrosivity of treated water.

(iii) If the Department grants an asbestos waiver, the supplier is not required to sample for asbestos as specified in 11.19(3)(d).

(A) The waiver is effective for one nine-year compliance cycle.

(f)Sampling Requirements for Consecutive Systems with Their Own Sources

(i) For consecutive systems, the Department may modify the inorganic chemical sampling requirements if the system meets all of the following criteria:

(A) The purchased water enters the distribution system separate from any source owned by the consecutive system.

(B) The interconnection of the systems justifies the modification of sampling requirements.

(ii) The supplier must comply with the Department-specified schedule.

11.19(4)Compliance Determination for Inorganic Chemicals

(a) If the supplier samples more frequently than annually, MCL compliance is based on the LRAA.

(i) If a confirmation sample is required, the original sample result will be replaced with the average of the original sample result and the confirmation sample result when calculating the LRAA.

(A) If the supplier fails to collect the confirmation sample, the original sample result will be used when calculating the LRAA.

(ii) If a sample result is less than (<) the cited detection limit, the sample result will be given a value of zero when calculating the LRAA.

(b) If the supplier samples annually or less frequently, MCL compliance is based on each individual sample result, unless a confirmation sample is required.

(i) If a confirmation sample is required, compliance is based on the average of the sample result and its confirmation sample result.

(A) If the supplier fails to collect the confirmation sample, the original sample result will be used to determine compliance.

(ii) If the average of any sample result and its confirmation sample result is greater than (>) the MCL, the supplier must increase the sampling frequency to quarterly as specified in 11.19(3)(b)(vi). This average will count as the first quarter sample result and compliance with the MCL will be based on the LRAA.

11.19(5)MCL Violations for Inorganic Chemicals

The following constitute inorganic chemical MCL violations:

(a) The LRAA at any entry point is greater than (>) the MCL for any inorganic chemical.

(b) The LRAA, calculated before four consecutive quarters of samples have been collected at any entry point or sampling location, is greater than (>) the MCL for any inorganic chemical regardless of the subsequent sample results.

11.19(6)Response to MCL Violations for Inorganic Chemicals

In the event of an inorganic chemical MCL violation, the supplier must:

(a) Notify the Department no later than 48 hours after the violation occurs.

(b) Distribute Tier 2 public notice as specified in 11.33.

11.19(7)Response to Exceeding the Secondary MCL for Fluoride

(a) For community water systems, if a fluoride sample result is greater than (>) the SMCL of 2.0 mg/L and less than (<) the MCL (4.0 mg/L), the supplier must distribute public notice as specified in this section, 11.19(7).

(b) The supplier must distribute the public notice no later than 12 months after the day the supplier learns of the exceedance.

(i) On a case-by-case basis, the Department may require the supplier to distribute the public notice sooner than 12 months.

(c) The supplier must submit a copy of the notice to the Department and all new billing units and new customers at the time service begins.

(d) If the public notice is posted, the notice must remain in place for as long as the SMCL is exceeded or seven days, whichever is longer.

(e) The supplier must redistribute the notice at least annually for as long as the SMCL is exceeded.

(i) On a case-by-case basis, the Department may require the supplier to redistribute the notice more frequently than annually.

(f) The public notice, including repeat notices, must comply with the requirements for Tier 3 public notice as specified in 11.33.

(g) The supplier must include the following language in the public notice exactly as written and provide the specific information for the text in brackets:

(i) This is an alert about your drinking water and a cosmetic dental problem that might affect children under nine years of age. At low levels, fluoride can help prevent cavities, but children drinking water containing more than 2 milligrams per liter (mg/L) of fluoride may develop cosmetic discoloration of their permanent teeth (dental fluorosis). The drinking water provided by your community water system [name] has a fluoride concentration of [value] mg/L.

Dental fluorosis, in its moderate or severe forms, may result in a brown staining and/or pitting of the permanent teeth. This problem occurs only in developing teeth, before they erupt from the gums. Children under nine years of age should be provided with alternate sources of drinking water or water that has been treated to remove the fluoride to avoid the possibility of staining and pitting of their permanent teeth. You may also want to contact your dentist about proper use by young children of fluoride-containing products. Older children and adults may safely drink the water.

Drinking water containing more than 4 mg/L of fluoride (the Colorado Department of Public Health and Environment's drinking water standard) can increase your risk of developing bone disease. Your drinking water does not contain more than 4 mg/L of fluoride, but we're required to notify you when we discover that the fluoride levels in your drinking water exceed 2 mg/L because of this cosmetic dental problem.

For more information, please call [name of water system contact] of [name of community water system] at [phone number]. Some home water treatment units are also available to remove fluoride from drinking water. To learn more about available home water treatment units, you may call NSF International at 1-877-8 -NSF-HELP.

5 CCR 1002-11.19

38 CR 07, April 10, 2015, effective 4/30/2015

41 CR 11, June 10, 2018, effective 6/30/2018

41 CR 23, December 10, 2018, effective 12/30/2018

43 CR 07, April 10, 2020, effective 4/30/2020

43 CR 17, September 10, 2020, effective 9/30/2020

45 CR 24, December 25, 2022, effective 1/14/2023