Code of Massachusetts Regulations › 310 CMR - DEPARTMENT OF ENVIRONMENTAL PROTECTION › Title 310 CMR 22.00 - Drinking Water › Section 22.07B - Maximum Contaminant Levels (MCLs) for Volatile Organic Compounds (VOC)

Current through Register 1525, July 5, 2024
(1)
Volatile Organic
			 MCLs
. The following maximum contaminant levels for organic
			 contaminants apply to community and non-transient, non-community water systems.
CAS No
.
Contaminant
MCL (mg/l)
(a)
75-01-4
Vinyl chloride
0.002
(b)
71-43-2
Benzene
0.005
(c)
56-23-5
Carbon tetrachloride
0.005
(d)
107-06-2
1,2-Dichloroethane
0.005
(e)
79-01-6
Trichloroethylene
0.005
(f)
106-46-7
para-Dichlorobenzene
0.005
(g)
75-35-4
1,1-Dichloroethylene
0.007
(h)
71-55-6
1,1,1-Trichloroethane
0.2
(i)
156-59-2
cis-1,2-Dichloroethylene
0.07
(j)
78-87-5
1,2-Dichloropropane
0.005
(k)
100-41-4
Ethylbenzene
0.7
(l)
108-90-7
Monochlorobenzene
0.1
(m)
95-50-1
o-Dichlorobenzene
0.6
(n)
100-42-5
Styrene
0.1
(o)
127-18-4
Tetrachloroethylene
0.005
(p)
108-88-3
Toluene
1
(q)
156-60-5
trans-1,2-Dichloroethylene
0.1
(r)
1330-20-7
Xylenes (total)
10
(s)
75-09-2
Dichloromethane
0.005
(t)
120-82-1
1,2,4-Trichlorobenzene
0.07
(u)
79-00-5
1,1,2-Trichloroethane
0.005
(2)
VOC Sampling Requirements
. Beginning with the initial
			 compliance period analysis of the contaminants listed in 310 CMR 22.07B(1) for
			 the purpose of determining compliance with the maximum contaminant level the
			 monitoring shall be conducted as follows:
(a)
VOC Ground Water Monitoring Protocols
. Groundwater
			 systems shall take a minimum of one sample at every entry point to the
			 distribution system which is representative of each well after treatment
			 (sampling point). If conditions warrant, the Department may designate
			 additional sampling points within the distribution system or at the consumer's
			 tap which more accurately determines consumer exposure. Each sample must be
			 taken at the same sampling point unless the Department determine that
			 conditions make another sampling point more representative of each source,
			 treatment plant, or within the distribution system.
(b)
VOC Surface Water Monitoring
			 Protocols
. Surface water systems (or combined surface/ground)
			 shall take a minimum of one sample at points in the distribution system that
			 are representative of each source or at each entry point to the distribution
			 system after treatment (sampling point). If conditions warrant, the Department
			 may designate additional sampling points within the distribution system or at
			 the consumer's tap which more accurately determines consumer exposure. Each
			 sample must be taken at the same sampling point unless conditions make another
			 sampling point more representative of each source, treatment plant, or within
			 the distribution system.
(c)
Multiple Sources
. If the 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 representative
			 of all sources is being used).
(d)
Initial VOCs Sampling Frequency
. Each community and
			 non-transient non-community water system shall take four consecutive quarterly
			 samples for each contaminant listed in 310 CMR 22.07B(1) during each compliance
			 period, beginning in the initial compliance period.
(e)
VOC Grandfathered Data with
			 No Detects - Reduced Monitoring
. If the initial monitoring for
			 contaminants listed in 310 CMR 22.07B(1) as allowed in 310 CMR 22.07B(10), has
			 been completed by December 31, 1992, and the system did not exceed the
			 detection levels in 310 CMR 22.07B(4) any contaminant listed in 310 CMR
			 22.07B(1), then each ground and surface water system shall take one sample
			 annually beginning with the initial compliance period.
(f)
Reduced VOC Sampling -
			 Annually
. Groundwater and surface water systems which do not
			 detect one of the contaminants listed in 310 CMR 22.07B(1) after conducting the
			 initial round of monitoring required in 310 CMR 22.07B(2)(a) and (b) shall take
			 one sample annually.