Authority: IC 13-13-5; IC 13-14-8-7; IC 13-14-9; IC 13-18-3;
IC 13-18-16
Affected: IC 13-18
Sec. 4.
(a) The
following MCLs for inorganic chemicals apply to all CWSs, NTNCWSs, and TWSs
except as provided in subsection (b):
| Contaminant |
Level in Milligrams Per Liter |
| Nitrate |
10 (as nitrogen) |
| Nitrite |
1 (as nitrogen) |
| Nitrate and nitrite |
10 (as nitrogen) |
(b)
The
commissioner may allow nitrate levels up to, but not to exceed, twenty (20)
milligrams per liter in a noncommunity water system if the
supplier of water
meets all of the following conditions:
(1)
Such water will not be available to children under six (6) months of
age.
(2) There will be continuous
posting of the fact that nitrate levels exceed ten (10) milligrams per liter
and the potential health effects of exposure.
(3) Local and state public health authorities
shall be notified annually of nitrate levels that exceed ten (10) milligrams
per liter.
(4) No adverse health
effects shall result.
(5) The
commissioner may require additional notice to the public as provided by
327
IAC 8-2.1-14.
(c) The following
MCL for fluoride applies to
all CWSs:
Contaminant Level in Milligrams Per Liter
Fluoride 4.0
(d) The following MCLs for inorganic
chemicals apply to all CWSs and NTNCWSs:
| Contaminant |
Level in Milligrams Per Liter Except Asbestos |
| Antimony |
0.006 |
| Arsenic |
0.0101
|
| Asbestos |
7 (MFL)
2
|
| Barium |
2 |
| Beryllium |
0.004 |
| Cadmium |
0.005 |
| Chromium |
0.1 |
| Cyanide (free) |
0.2 |
| Mercury |
0.002 |
| Selenium |
0.05 |
| Thallium |
0.002 |
1 Effective January 1, 2006. Until
then, the arsenic MCL is 0.05 mg/l.
2MFL = million fibers per liter
greater than ten (10) micrometers.
(e) For the inorganic chemicals listed in
this section and nickel, the monitoring frequency is specified in section 4.1
of this rule and analytical methods are specified in section 4.2 of this
rule.
(f) The
commissioner hereby
identifies the following as the
BAT, treatment technique, or other means
available for achieving compliance with the MCLs for inorganic contaminants
identified in subsections (a), (c), and (d), except fluoride:
| BAT for Inorganic Chemicals Listed in This
Section |
| Chemical Name |
BATs |
| Antimony |
2,7 |
| Arsenic4
|
1, 2, 5, 6, 7, 9, 125
|
| Asbestos |
2,3,8 |
| Barium |
5,6,7,9 |
| Beryllium |
1,2,5,6,7 |
| Cadmium |
2,5,6,7 |
| Chromium |
2,5,62,7 |
| Cyanide |
5,7,10 |
| Mercury |
21,4,61,71
|
| Nitrate |
5,7,9 |
| Nitrite |
5,7 |
| Selenium |
1,23,6,7,9 |
| Thallium |
1,5 |
1 BAT only if influent mercury
concentrations less than ten (10) micrograms per liter.
2 BAT for Chromium III
only.
3 BAT for Selenium IV only.
4 BATs for Arsenic V. Preoxidation
may be required to convert Arsenic III to Arsenic V. Arsenic BATs apply
beginning January 1, 2006.
5 To obtain high removals, iron to
arsenic ratio must be at least 20:1.
Key to BATs in Table
1 = Activated alumina
2 = Coagulation/filtration (not BAT for
systems < 500 service connections)
3 = Direct and diatomite filtration
4 = Granular activated carbon
5 = Ion exchange
6 = Lime softening (not BAT for systems <
500 service connections)
7 =
Reverse osmosis
8 = Corrosion
control
9 = Electrodialysis
10 = Chlorine
11 = Ultraviolet
12 = Oxidation/filtration
(g) The
commissioner, pursuant to
Section 1412 of the
Act, hereby identifies in the following table the
affordable technology, treatment technique, or other means available to systems
serving ten thousand (10,000) persons or fewer for achieving compliance with
the
MCL for arsenic that will be applicable beginning January 1, 2006:
| Small System Compliance Technologies
(SSCTs)1 for Arsenic2
|
| Small system compliance technology |
Affordable for listed small system
categories3
|
| Activated alumina (centralized) |
All size categories |
| Activated alumina
(point-of-use)4
|
All size categories |
| Coagulation/filtration5
|
501-3,300, 3,301-10,000 |
| Coagulation-assisted microfiltration |
501-3,300, 3,301-10,000 |
| Electrodialysis reversal6
|
501-3,300, 3,301-10,000 |
| Enhanced coagulation/filtration |
All size categories |
| Enhanced lime softening (pH > 10.5) |
All size categories |
| Ion exchange |
All size categories |
| Lime softening5
|
501-3,300, 3,301-10,000 |
| Oxidation/filtration7
|
All size categories |
| Reverse osmosis
(centralized)6
|
501-3,300, 3,301-10,000 |
| Reverse osmosis
(point-of-use)4
|
All size categories |
1 Section 1412(b)(4)(E)(ii) of the
Act specifies that SSCTs must be affordable and technically feasible for small
systems.
2SSCTs for Arsenic V. Preoxidation
may be required to convert Arsenic III to Arsenic V.
3The Act (ibid.) specifies three (3)
categories of small systems as follows:
(A) Those serving twenty-five (25) or more,
but fewer than five hundred one (501).
(B) Those serving more than five hundred
(500), but fewer than three thousand three hundred one (3,301).
(C) Those serving more than three thousand
three hundred (3,300), but fewer than ten thousand one (10,001).
4 When POU or POE devices are used
for compliance, programs to ensure proper long term operation, maintenance, and
monitoring must be provided by the water system to ensure adequate
performance.
5 Unlikely to be installed solely
for arsenic removal. May require pH adjustment to optimal range if high
removals are needed.
6Technologies reject a large
volume of water; may not be appropriate for areas where water quantity may be
an issue.
7 To obtain high removals, iron to
arsenic ratio must be at least 20:1.
