Code of Massachusetts Regulations › 310 CMR - DEPARTMENT OF ENVIRONMENTAL PROTECTION › Title 310 CMR 22.00 - Drinking Water › Section 22.06 - Inorganic Chemical Maximum Contaminant Levels, Monitoring Requirements and Analytical Methods

Current through Register 1525, July 5, 2024
(1)
Monitoring
. A Supplier of Water shall collect samples
			 of water as specified in 310 CMR 22.06(4) and provide for analysis of such
			 samples for inorganic chemical contaminants listed in 310 CMR 22.06(2)
			 consistent with the requirements set forth in 310 CMR 22.06(5) through (9) and
			 methods set forth in 310 CMR 22.06(16).
All analytical results shall be rounded to the same number of
				significant figures as the applicable MCL or SMCL.
(2)
Inorganic Maximum Contaminant
			 Levels (MCLs)
. The Maximum Contaminant Levels for inorganic
			 contaminants specified in 310 CMR 22.06(2)(b) through (g) and (k) through (q)
			 apply to Community Water Systems and Non-transient Non-community Water Systems.
			 The Maximum Contaminant Level specified in 310 CMR 22.06(2)(a) only applies to
			 Community Water Systems. The Maximum Contaminant Levels specified in 310 CMR
			 22.06(2)(h) through (j) apply to Community, Non-transient Non-community, and
			 Transient Non-community Water Systems. The Maximum Contaminant Level for
			 arsenic is 0.05 milligrams per liter for Community Water Systems and
			 Non-transient Non-community Water Systems until January 23, 2006.
MAXIMUM CONTAMINANT LEVELS FOR INORGANIC CHEMICALS
Contaminant
MCL (mg/l)
(a) Fluoride (C)
4.0
(b) Asbestos (C, NTNC)
7 Million Fibers/liter (longer than 10
							 µm)
(c) Arsenic (C,NTNC)
0.010
(d) Barium (C,NTNC)
2
(e) Cadmium (C,NTNC)
0.005
(f) Chromium (C,NTNC)
0.1
(g) Mercury (C,NTNC)
0.002
(h) Nitrate (C,NTNC,TNC)
10 (as Nitrogen)
(i) Nitrite (C,NTNC,TNC)
1 (as Nitrogen)
(j) Total Nitrate & Nitrite (C,NTNC,TNC)
10 (as Nitrogen)
(k) Selenium (C,NTNC)
0.05
(l) Antimony (C,NTNC)
0.006
(m) Beryllium (C,NTNC)
0.004
(n) Cyanide (as free Cyanide) (C,NTNC)
0.2
(o) Nickel (C,NTNC)
[Reserved] (Under review)
(p) Thallium (C,NTNC)
0.002
(q) Perchlorate (C,NTNC)
0.00201
C = Community Water Systems; NTNC = Non-transient Non-community
				Water Systems;
TNC = Transient Non-community Water Systems
1 The Department will review and
				revise as necessary the perchlorate MCL within six years of its promulgation,
				taking into account new data on health effects, sources and occurrence,
				Treatment Techniques and associated issues, analytical feasibility and any
				other relevant information.
(3)
Inorganic Chemicals
			 (IOC)
. Sampling and Analytical Requirements: Community Water
			 Systems and Non-transient Non-community Water Systems shall conduct monitoring
			 to determine compliance with the Maximum Contaminant Levels specified in 310
			 CMR 22.06(2) in accordance with 310 CMR 22.06. Transient, Non-community Water
			 Systems shall conduct monitoring to determine compliance with the MCLs for
			 nitrate, nitrite and total nitrate in 310 CMR 22.06(2)(h) through (j) (as
			 appropriate) in accordance with 310 CMR 22.06.
(4)
Sampling
			 Protocol
. Monitoring shall be as follows:
(a)
Ground Water Sampling
			 Points
. Groundwater systems shall take one sample at every entry
			 point to the Distribution System which is representative of each well after
			 treatment (Sampling Point) beginning in the Compliance Period starting January
			 1, 1993. The system shall take each sample at the same Sampling Point unless
			 conditions make another Sampling Point more representative of each source or
			 treatment plant.
(b)
Surface Water Sampling Points
. Surface water systems
			 (
Note
: or purposes of 310 CMR 22.06(4)(b), Surface
			 Water systems include systems with a combination of surface and ground sources)
			 shall take a minimum of one sample at every entry point to the Distribution
			 System after any application of treatment or in the Distribution System at a
			 point which is representative of each source after treatment ( Sampling Point)
			 beginning in the Compliance Period beginning January 1, 1993. The system shall
			 take each sample at the same Sampling Point unless conditions make another
			 Sampling Point more representative of each source or treatment plant.
(c)
Multiple
			 Sources
. If a system draws water from more than one 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
			 (
i.e.
, when water is representative of all sources being
			 used).
(d)
Composite
			 Sampling
. The total number of samples which must be analyzed may
			 be reduced by compositing samples. Composite samples from a maximum of five
			 Sampling Points are allowed provided that the detection limit of the method
			 used for analysis is less than 1/5 of the MCL and none of the samples to be
			 composited are representative of multiple sources. Compositing of samples must
			 be approved by the Department and must be done in the laboratory. Compositing
			 of source with previous detects is not allowed, unless otherwise authorized by
			 the Department.
1. If the concentration in the
			 composite sample is greater than or equal to 1/5 of the MCL of any inorganic
			 chemical, then a follow-up sample must be analyzed within 14 days from each
			 Sampling Point included in the composite. These samples must be analyzed for
			 the contaminants that exceeded 1/5 of the MCL in the composite sample.
			 Detection limits for each analytical method and MCL are the following:
DETECTION LIMITS FOR INORGANIC CONTAMINANTS
Contaminant
MCL(mg/l)
Methodology
Detection Limit
							 (mg/l)
Antimony
0.006
Atomic Absorption; furnace
0.003
0.00085
ICP-Mass Spectrometry
0.0004
Hydride-Atomic absorption
0.001
Arsenic
0.0106
Atomic Absorption; Furnace
0.001
Atomic Absorption; Platform-Stabilized
							 Temperature
0.00057
Atomic Absorption; Gaseous Hydride
0.001
ICP- Mass Spectrometry
0.00148
Asbestos
7 MFL1
Transmission Electron Microscopy
0.2 MFL
Barium
2
Atomic Absorption; furnace technique
0.002
Atomic Absorption; direct aspiration
0.1
Inductively Coupled Plasma
0.002 (0.001)
Beryllium
0.004
Atomic Absorption; furnace
0.0002
Atomic Absorption; platform
0.000025
Inductively Coupled Plasma2
0.0003
ICP-Mass Spectrometry
0.0003
Cadmium
0.005
Atomic Absorption; furnace technique
0.0001
Inductively Coupled Plasma
0.001
Chromium
0.1
Atomic Absorption; furnace technique
0.001
Inductively Coupled Plasma
0.007 (0.001)
Cyanide
0.2
Distillation,
							 Spectrophotometric3
0.02
Distillation, Automated,
							 Spectrophotometric3
0.005
Distillation, Selective Electrode 
							 3,
																4
0.05
Distillation, Amenable, Spectrophotometric 
							 4
0.02
UV, Distillation,
							 Spectrophotometric11
0.0005
Micro Distillation, Flow Injection,
Spectrophotometric3
0.0006
Ligand Exchange with
							 Amperometry4
0.0005
Mercury
0.002
Manual Cold Vapor Technique
0.0002
Automated Cold Vapor Technique
0.0002
Nickel
Reserved
Nitrate
10 (as N)
Manual Cadmium Reduction
0.01
Automated Hydrazine Reduction
0.01
Automated Cadmium Reduction
0.05
Ion Selective Electrode
1
Ion Chromatography
0.01
Capillary Ion Electrophoresis
0.076
Nitrite
1 (as N)
Spectrophotometric
0.01
Automated Cadmium Reduction
0.05
Manual Cadmium Reduction
0.01
Ion Chromatography
0.004
Capillary Ion Electrophoresis
0.103
Perchlorate
0.0020
Ion Chromatography9
0.001010
LC/MS or LC/MS/MS
0.0010
IC/MS or IC/MS/MS
0.0010
Selenium
0.05
Atomic Absorption; furnace
0.002
Atomic Absorption: gaseous hydride
0.002
Sodium
See
310 CMR 22.06A
Thallium
0.002
Atomic Absorption; furnace
0.001
Atomic Absorption; platform
0.00075
ICP-Mass Spectrometry
0.0003
1 MFL = million fibers per liter
				>10 µm.
2 Using a 2X preconcentration step
				as noted in Method 200.7. Lower MDLs may be achieved when using a 4X
				preconcentration.
3 Screening methods for total
				cyanides.
4 Measures "free" cyanides when
				distillation, digestion, or ligand exchange is omitted.
5 Lower MDLs are reported using
				stabilized temperature graphite furnace atomic absorption.
6 The MCL for arsenic is effective
				January 23, 2006. Until then, the MCL is 0.05 mg/l.
7 The MDL reported for EPA method
				200.9 (Atomic Absorption; Platform---Stabilized Temperature) was determined
				using a 2x concentration step during sample digestion. The MDL determined for
				samples analyzed using direct analyses (
i.e
., no sample
				digestion) will be higher. Using multiple deposition, EPA 200.9 is capable of
				obtaining MDL of 0.0001 mg/l.
8 Using selective ion monitoring,
				EPA Method 200.8 (ICP-MS) is capable of obtaining a MDL of 0.0001 mg/l.
9 Analysis must be conducted using
				EPA Method 314.0, revision 1.0, November 1999 as modified to achieve the stated
				detection limit or EPA Method 314.1.
10 Minimum Reporting Level (MRL).
				EPA Method 314.0 is capable of obtaining a MDL of less than 0.0010 mg/l.
11 Measures total cyanides when
				UV-digestor is used, and "free" cyanides when UV-digestor is bypassed.
2. If the population served by the
			 system is >3,300 persons, then compositing may only be permitted at Sampling
			 Points within a single system. In systems serving <3,300 persons,
			 compositing among different systems may be allowed with the approval of the
			 Department, provided the five-sample limit is maintained.
3. If duplicates of the original sample taken
			 from each Sampling Point used in the composite are available, the system may
			 use these instead of resampling. The duplicates must be analyzed and the
			 results reported to the Department within 14 days after completion of the
			 composite analyses or before the holding time for the control sample is
			 exceeded, whichever is sooner.
(e)
Frequency Requirements for
			 IOC Monitoring
. The frequency of monitoring for asbestos shall be
			 in accordance with 310 CMR 22.06(5); the frequency of monitoring for antimony,
			 arsenic, barium, beryllium, cadmium, chromium, cyanide, fluoride, mercury,
			 nickel, selenium and thallium shall be in accordance with 310 CMR 22.06(6); the
			 frequency of monitoring for nitrate shall be in accordance with 310 CMR
			 22.06(7); the frequency of monitoring for nitrite shall be in accordance with
			 310 CMR 22.06(8); and the frequency of monitoring for perchlorate shall be in
			 accordance with 310 CMR 22.06(9).
(f)
Consecutive System
			 Monitoring
. Public Water Systems that obtain water from another
			 Public Water System are exempt from conducting compliance monitoring for the
			 purchased portion of the system for the inorganic chemicals under 310 CMR
			 22.06, provided that the system from which the water is obtained has conducted
			 the analyses required under 310 CMR 22.06, unless otherwise specified by the
			 Department. These systems are not exempt from 310 CMR 22.06(5) asbestos
			 sampling.