Connecticut Administrative Code
Title 22a - Environmental Protection
426 - Connecticut Water Quality Standards
Section 22a-426-9 - Environmental criteria

Universal Citation: CT Reg of State Agencies 22a-426-9

Current through March 14, 2024

(a) Surface Water Quality Criteria

(1) Surface Waters shall meet the criteria listed in Table 1 to support the designated uses identified for their particular classification.

Table 1 - Surface Water Criteria by Classification

Parameter

Class AA

Class A

Class B

Class SA

Class SB

Aesthetics

Uniformly excellent.

Uniformly excellent.

Good to excellent.

Uniformly excellent.

Good to excellent.

Dissolved Oxygen

Not less than 5 mg/l at any time.

Not less than 5 mg/l at any time.

Not less than 5 mg/l at any time.

Acute: Not less than 3.0 mg/l.

Chronic: Not less than 4.8 mg/l with cumulative periods of dissolved oxygen in the 3.0 - 4.8 mg/l range as detailed in Note 1 to this table.

Acute: Not less than 3.0 mg/l.

Chronic: Not less than 4.8 mg/l with cumulative periods of dissolved oxygen in the 3.0 - 4.8 mg/l range as detailed in Note 1 to this table.

Sludge deposits-solid refuse-floating solids-oils and grease-scum

None other than of natural origin.

None other than of natural origin.

None except for small amounts that may result from the discharge from a permitted waste treatment facility and none exceeding levels necessary to protect and maintain all designated uses.

None other than of natural origin.

None except for small amounts that may result from the discharge from a grease waste treatment facility providing appropriate treatment and none exceeding levels necessary to protect and maintain all designated uses.

Color

None other than of natural origin

None other than of natural origin.

None which causes visible discoloration of the surface water outside of any designated zone of influence.

None other than of natural origin.

None resulting in obvious discoloration of the surface water outside of any designated zone of influence.

Suspended and settleable solids

None in concentrations or combinations which would impair designated uses; none aesthetically objectionable; none which would significantly alter the physical or chemical composition of the bottom; none which would adversely impact aquatic organisms living in or on the bottom substrate.

None in concentrations or combinations which would impair designated uses; none aesthetically objectionable; none which would significantly alter the physical or chemical composition of the bottom; none which would adversely impact aquatic organisms living in or on the bottom substrate.

None in concentrations or combinations which would impair the most sensitive designated use; none aesthetically objectionable; none which would significantly alter the physical or chemical composition of the bottom; and none which would adversely impact aquatic organisms living in or on the bottom sediments; shall not exceed 10 mg/l over ambient concentrations.

None other than of natural origin.

None in concentrations or combinations which would impair the designated uses; none aesthetically objectionable; none which would significantly alter the physical or chemical composition of bottom sediments; none which would adversely impact organisms living in or on the bottom sediment.

Silt or sand deposits

None other than of natural origin except as may result from normal agricultural, road maintenance, construction activity or dredging activity or discharge of dredged or fill materials provided all reasonable controls or Best Management Practices are used in such activities and all designated uses are protected and maintained.

None other than of natural origin except as may result from normal agricultural, road maintenance, construction activity, dredging activity or the discharge of dredged or fill materials provided all reasonable controls or Best Management Practices are used in such activities and all designated uses are protected and maintained.

None other than of natural origin except as may result from normal agricultural, road maintenance, construction activity, dredging activity or discharge of dredged or fill materials provided all reasonable controls or Best Management Practices are used in such activities and all designated uses are protected and maintained.

None other than of natural origin except as may result from normal agricultural, road maintenance, construction activity, dredging activity or the discharge of dredged or fill materials provided all reasonable controls or Best Management Practices are used in such activities and all designated uses are protected and maintained.

None other than of natural origin except as may result from normal agricultural, road maintenance, construction activity, dredging activity or discharge of dredged or fill materials provided all reasonable controls or Best Management Practices are used in such activities and all designated uses are protected and maintained.

Turbidity

Shall not exceed 5 NTU over ambient levels and none exceeding levels necessary to protect and maintain all designated uses. All reasonable controls or Best Management Practices are to be used to control turbidity.

Shall not exceed 5 NTU over ambient levels and none exceeding levels necessary to protect and maintain all designated uses. All reasonable controls or Best Management Practices are to be used to control turbidity.

Shall not exceed 5 NTU over ambient levels and none exceeding levels necessary to protect and maintain all designated uses. All reasonable controls or Best Management Practices are to be used to control turbidity.

None other than of natural origin except as may result from normal agricultural, road maintenance, or construction activity, dredging activity or discharge of dredged or fill materials provided all reasonable controls and Best Management Practices are used to control turbidity and none exceeding levels necessary to protect and maintain all designated uses.

None other than of natural origin except as may result from normal agricultural, road maintenance, or construction activity, or discharge from a waste treatment facility providing appropriate treatment, dredging activity or discharge of dredged or fill materials provided all reasonable controls and Best Management Practices are used to control turbidity and none exceeding levels necessary to protect and maintain all designated uses.

Indicator bacteria

See Table 2A of this section.

See Table 2A of this section.

See Table 2A of this section.

See Table 2B of this section.

See Table 2B of this section.

Taste and Odor

None other than of natural origin.

None other than of natural origin.

None that would impair any uses specifically assigned to this Class.

As naturally occurs.

As naturally occurs. None that would impair any uses specifically assigned to this Class.

pH

As naturally occurs.

As naturally occurs.

6.5 - 8.0

6.8 - 8.5

6.8 - 8.5

Allowable Temperature Increase

There shall be no changes from natural conditions that would impair any existing or designated uses assigned to this Class and in no case exceed 85o F, or in any case raise the temperature of surface water more than 4o F.

There shall be no changes from natural conditions that would impair any existing or designated uses assigned to this Class and, in no case exceed 85o F, or in any case raise the temperature of surface water more than 4o F.

There shall be no changes from natural conditions that would impair any existing or designated uses assigned to this Class and, in no case exceed 85o F, or in any case raise the temperature of surface water more than 4o F.

There shall be no changes from natural conditions that would impair any existing or designated uses assigned to this Class and, in no case exceed 83o F, or in any case raise the temperature of the receiving water more than 4 o F. During the period including July, August and September, the temperature of the receiving water shall not be raised more than 1.5o F unless it can be shown that spawning and growth of indigenous organism will not be significantly affected. The allowable temperature increase resulting from discharges in the estuarine segments of the Housatonic, Connecticut and Thames Rivers shall be consistent with the criteria for the non-tidal segments.

There shall be no changes from natural conditions that would impair any existing or designated uses assigned to this Class and, in no case exceed 83o F, or in any case raise the temperature of the receiving water more than 4o F. During the period including July, August and September, the temperature of the receiving water shall not be raised more than 1.5 o F unless it can be shown that spawning and growth of indigenous organisms will not be significantly affected. The allowable temperature increase resulting from discharges in the estuarine segments of the Housatonic, Connecticut and Thames Rivers shall be consistent with the criteria for the non-tidal segments.

Chemical constituents

None in concentrations or combinations which would be harmful to designated uses. Refer to Table 3 of this section and sections 22a-426-4(a)(5); 22a-426-4(a)(9); 22a-426-4(a)(9)(B); 22a-426-4(a)(11); 22a-426-4(l); 22a-426-4(m); 22a-426-9(a)(3); 22a-426-9(a)(4) and 22a-426-9(a)(5) of the Regulations of Connecticut State Agencies.

Nutrients

The loading of nutrients, principally phosphorus and nitrogen, to any surface water body shall not exceed that which supports maintenance or attainment of designated uses.

The loading of nutrients, principally phosphorus and nitrogen, to any surface water body shall not exceed that which supports maintenance or attainment of designated uses.

The loading of nutrients, principally phosphorus and nitrogen, to any surface water body shall not exceed that which supports maintenance or attainment of designated uses.

The loading of nutrients, principally phosphorus and nitrogen, to any surface water body shall not exceed that which supports maintenance or attainment of designated uses.

The loading of nutrients, principally phosphorus and nitrogen, to any surface water body shall not exceed that which supports maintenance or attainment of designated uses

Sodium

Not to exceed 20 mg/l.

None other than of natural origin.

Biological condition

Sustainable, diverse biological communities of indigenous taxa shall be present. Moderate changes, from natural conditions, in the structure of the biological communities, and minimal changes in ecosystem function may be evident; however, water quality shall be sufficient to sustain a biological condition within the range of Connecticut Biological Condition Gradient Tiers 1-4 as assessed along a 6 tier stressor gradient of Biological Condition Gradient (See section 22a-426-5 of the Regulations of Connecticut State Agencies).

Sustainable, diverse biological communities of indigenous taxa shall be present. Moderate changes, from natural conditions, in the structure of the biological communities, and minimal changes in ecosystem function may be evident; however, water quality shall be sufficient to sustain a biological condition within the range of Connecticut Biological Condition Gradient Tiers 1-4 as assessed along a 6 tier stressor gradient of Biological Condition Gradient (See section 22a-426-5 of the Regulations of Connecticut State Agencies).

Sustainable, diverse biological communities of indigenous taxa shall be present. Moderate changes, from natural conditions, in the structure of the biological communities, and minimal changes in ecosystem function may be evident; however, water quality shall be sufficient to sustain a biological condition within the range of Connecticut Biological Condition Gradient Tiers 1-4 as assessed along a 6 tier stressor gradient of Biological Condition Gradient (See section 22a-426-5 of the Regulations of Connecticut State Agencies).

Sustainable, diverse biological communities of indigenous taxa shall be present. Moderate changes, from natural conditions, in the structure of the biological communities, and minimal changes in ecosystem function may be evident; however, water quality shall be sufficient to sustain a healthy, diverse biological community

Sustainable, diverse biological communities of indigenous taxa shall be present. Moderate changes, from natural conditions, in the structure of the biological communities, and minimal changes in ecosystem function may be evident; however, water quality shall be sufficient to sustain a healthy, diverse biological community

Note 1

Cumulative Dissolved Oxygen exposure parameters: Dissolved Oxygen conditions in the area affected do not readily lend themselves to a single numeric criterion. Aquatic organisms are harmed based on a combination of minimum oxygen concentration and duration of the low Dissolved Oxygen excursion. The department established exposure allowances based upon EPA research and data, for 0.5 mg/l and 0.3 mg/l increment ranges. (See Table A in this note.) Given the environmental variability, the department has used a minimum Dissolved Oxygen criterion of 3.0 mg/l with an exposure allowance of no more than 2 days.

Table A. Dissolved Oxygen Chronic Cumulative Exposure Criteria for incremental ranges (0.5 mg/l and 0.3 mg/l) applicable to Class SA and SB waters.

Dissolved Oxygen Range (mg/l)

No. of Days Allowed

[LESS THAN] 4.8

[GREATER THAN EQUAL TO] 4.5

30

[LESS THAN] 4.5

[GREATER THAN EQUAL TO] 4.0

14

[LESS THAN] 4.0

[GREATER THAN EQUAL TO] 3.5

7

[LESS THAN] 3.5

[GREATER THAN EQUAL TO] 3.0

2

Because marine systems are variable, Dissolved Oxygen levels are unlikely to remain within one of the four incremental ranges presented in Table A. Typically, Dissolved Oxygen conditions would fall through a range to a minimum and then begin to rebound depending on weather and stratification conditions. To account for this, the number of days within each incremental Dissolved Oxygen range is pro-rated, as follows: A decimal fraction is calculated for each range, e.g., 10.5 days in the 4.5 - 4.8 mg/l range would produce a decimal fraction of 0.35 (0.35 = 10.5 days/ 30 days). As long as the sum of those fractions calculated for each range is less than 1.0, resource protection goals are maintained for larval recruitment.

In cases where data collection yields continuous Dissolved Oxygen readings or more frequent sampling results, the data can be interpreted using a 0.1 mg/l interval range. The number of allowable days is determined using the following method:

DOi = 13.0 / (2.80 + 1.84e-0.10ti )

where:

DOi = allowable Dissolved Oxygen concentration (mg/l)

ti = exposure interval duration in days

i = exposure interval

However, since most sampling programs do not result in frequent readings, a greater interval (presented in Table A) is recommended. Use of a larger interval results in a larger sum of fractions and is subsequently a more conservative measure of consistency with the Connecticut Water Quality Standards.

(2) Indicator bacteria are used to detect the presence of contamination by human or animal wastes. Tables 2A and 2B below provide the criteria for indicator bacteria. Due to the inherent uncertainty involved in sampling and analytically determining bacteria levels, exceedances of water quality criteria for indicator bacteria does not always indicate a water quality problem and therefore should be investigated by means of a sanitary survey or other appropriate means to determine sources of elevated indicator bacteria levels.

Table 2A - Indicator Bacteria - Freshwater

Designated Use

Indicator

Criteria by classification

Drinking water supply(1)

Total Coliform

AA

A

B

SA

SB

Monthly moving average less than 100/100 ml

Single sample maximum 500/100 ml

Recreation(2)(3) - Designated swimming(4)

Escherichia coli

Geometric mean less than 126/100 ml

Single sample maximum 235/100 ml

Recreation(2)(3) -

Non Designated Swimming(5)

Escherichia coli

Geometric mean less than 126/100 ml

Single sample maximum 410/100 ml

Recreation(2)(3) -

All other uses

Escherichia coli

Geometric mean less than 126/100 ml

Single sample maximum 576/100 ml

Table 2B - Indicator Bacteria - Saltwater

Designated Use

Indicator

Criteria by classification

AA

A

B

SA

SB

Shell fishing(6) - Direct Consumption

Fecal coliform

Geometric mean less than 14/100 ml

90% of samples less than 31/100 ml

Shell fishing(6) -

Indirect consumption

Fecal coliform

Geometric mean less than 88/100 ml

90% of samples less than 260/100 ml

Recreation - Designated swimming(4)

Enterococci

Geometric mean less than 35/100ml

Single sample maximum 104/100 ml

Recreation -

All other uses

Enterococci

Geometric mean less than 35/100 ml

Single sample maximum 500/100 ml

Notes for Tables 2A and 2B

(1) Criteria applies only at the drinking water supply intake structure.

(2) Criteria for the protection of recreational uses in Class B waters do not apply when disinfection of sewage treatment plant effluents is not required consistent with section 22a-426-4(a)(9)(E) of the Regulations of Connecticut State Agencies.

(3) See section 22a-426-9(a)(2) of the Regulations of Connecticut State Agencies.

(4) Procedures for monitoring and closure of bathing areas by state and local health authorities are specified in: Guidelines for Monitoring Bathing Waters and Closure Protocol, adopted jointly by the Department of Environmental Protection and the Department of Public Health, May 1989, revised April 2003 and updated December 2008.

(5) Includes areas otherwise suitable for swimming but which have not been designated by state or local authorities as bathing areas, waters which support tubing, water skiing, or other recreational activities where full body contact is likely.

(6) Criteria are based on utilizing the mTec method as specified in the U.S. Food and Drug Administration National Shellfish Sanitation Program-Model Ordinance (NSSP-MO) document Guide for the Control of Molluscan Shellfish 2007.

(3) Discharges to surface waters shall meet the criteria listed for chemical constituents in Table 3 of this section to ensure the particular surface waters support the uses identified for their particular classification and to assure that such discharges do not cause acute or chronic toxicity to freshwater and marine aquatic life, impair the biological integrity of freshwater and marine ecosystems, or create an unacceptable risk to human health.

(4) The Commissioner may amend the numeric criteria for the chemical constituents listed in Table 3 of this section in accordance with the provisions of Chapter 54 of the Connecticut General Statutes and the notice procedures specified in section 22a 426 of the Connecticut General Statutes on his or her own initiative, or upon request of any person or municipality that site-specific water quality criteria be adopted or amended, provided such request is supported by sound scientific and technical evidence demonstrating the following:
(A) Conditions at the specific site differ significantly from those used in establishing the statewide criteria;

(B) The proposed site-specific criteria are sufficiently stringent to protect all existing and designated uses of the water body; and

(C) The proposed site-specific criteria are derived in a manner consistent with sound scientific and technical principles, giving consideration to all applicable federal guidance.

(5) The Commissioner may adopt or amend criteria for any surface water or class of water, in accordance with the provisions of Chapter 54 of the Connecticut General Statutes and the notice procedures specified in section 22a-426 of the Connecticut General Statutes and in subparagraphs (A), (B), and (C) of subdivision (4) of this subsection, provided such change is supported by sound scientific and technical evidence, and existing and designated uses are fully protected.

Table 3 NUMERICAL WATER QUALITY CRITERIA FOR CHEMICAL CONSTITUENTS

Numerical Water Quality Criteria for Chemical Constituents (ug/L)1

Aquatic Life Criteria (2)(3)

Human health Criteria

Freshwater:

Class AA, A & B

Saltwater

Class SA & SB

Class B, SA & SB Waters

Class AA & A Waters

Chemical Constituents

CASRN

Acute4

Chronic5

Acute4

Chronic5

Consumption of Fish

Consumption of Water & Fish

Health Designation6

Inorganics7

Antimony

7440360

640

5.6

TT

Arsenic (total)

7440382

340

150

69

36

0.021

0.011

A

Beryllium

7440417

0.13

0.0077

TT

Cadmium

7440439

1.0

0.125

40

8.8

10,769

5

TT

Chromium (hex)

18540299

16

11

1,100

50

2,019

100

TT

Chromium (tri)

16065831

323

42

1,009,615

100

TT

Copper

7440508

14.3 8

4.8 9

4.8

3.1

1,300

TT

Copper (site-specific) 10

7440508

25.7

18.1

1,300

TT

Cyanide (Total)

57125

22

5.20

1

1

140

140

TT

Lead

7439921

30

1.2

210

8.1

15

TT

Mercury (Total)

7439976

1.4

0.77

1.8

0.94

0.051

0.050

TT-HB

Nickel

7440020

260.5

28.9

74

8.2

4,600

610

TT

Selenium (Total)

7782492

20

5

290

71

4,200

50

TT

Silver

7440224

1.02

1.9

107,692

175

TT

Thallium

7440280

0.47

0.24

TT

Zinc

7440666

65

65

90

81

26,000

7,400

TT

Volatiles

Acrolein

107028

3

3

9

6

TT

Acrylonitrile

107131

0.25

0.051

C

Benzene

71432

51

1.2

A

Bromoform

75252

140

4.3

C

Carbon Tetrachloride

56235

1.6

0.23

C

Chlorobenzene

108907

1,600

100

TT

Chlorodibromomethane

124481

13

0.40

C

Chloroethane

75003

2-Chloroethylvinyl Ether

110758

Chloroform

67663

470

5.7

C

Dichlorobromomethane

75274

17

0.55

C

1,1-Dichloroethane

75343

1,2-Dichloroethane

107062

37

0.38

C

1,1-Dichloroethylene

75354

3.2

0.057

C

1,2T-Dichloroethylene

156605

10,000

100

TT

1,2-Dichloropropane

78875

15

0.50

TT

1,3-Dichloropropylene

542756

21

0.34

TT

Ethylbenzene

100414

2,100

530

TT

Methyl Bromide

74839

1,500

47

TT

Methyl Chloride

74873

470

5.7

TT

Methylene Chloride

75092

590

4.6

C

1,1,2,2-Tetrachloroethane

79345

4.0

0.17

C-HB

Tetrachloroethylene

127184

3.3

0.69

TT

Toluene

108883

15,000

1,000

TT

1,1,1-Trichloroethane

71556

1,1,2-Trichloroethane

79005

16

0.59

C

Trichloroethlyene

79016

30

2.5

C

Vinyl Chloride

75014

2.4

0.025

C

GC/MS: Acid Compounds

2-Chlorophenol

95578

150

81

TT

2,4-Dichlorophenol

120832

290

77

TT

2,4-Dimethylphenol

105679

850

380

TT

3-Methyl-4-chlorophenol

59507

2-Methyl-4,6-Dinitrophenol

534521

280

13

TT

2,4-Dinitrophenol

51285

5,300

69

TT

2-Nitrophenol

88755

4-Nitrophenol

100027

Pentachlorophenol

87865

19

15

13

7.9

3.0

0.27

C-HB

Phenol

108952

860,000

10,000

TT

2,4,6-Trichlorophenol

88062

2.4

1.4

C-HB

Base Neutral Compounds

Acenaphthene

83329

6.1

2.7

TT-HB

Acenapthylene

208968

49.2

4.37

C-HB

Anthracene

120127

4.92

0.44

C-HB

Benzidene

92875

0.00020

0.000086

A

Benzo(a)anthracene

56553

0.018

0.0038

C-HB

Benzo(a)pyrene

50328

0.018

0.0038

C-HB

Benzo(b)fluoranthene

205992

0.018

0.0038

C-HB

Benzo(ghi)perylene

191242

4.92

0.44

C-HB

Benzo(k)fluoranthene

207089

0.018

0.0038

C-HB

Bis(2-chloroethoxy)Methane

111911

Bis(2-Chloroethyl)Ether

111444

0.53

0.030

C

Bis(2-Chloroisopropyl)Ether

108601

65,000

1,400

TT

Bis(2-Ethylhexyl)Phthalate

117817

2.2

1.2

C-HB

4-Bromophenylether

101553

Butyl Benzyl Phthalate

85687

1,900

1,500

TT-HB

2-Chloronapthylene

91587

1,600

1,000

TT-HB

4-Chlorophenylphenylether

7005723

Chrysene

218019

0.018

0.0038

C-HB

Dibenzo(a,h)anthracene

53703

0.010

0.0009

C-HB

1,2-Dichlorobenzene

95501

1,300

420

TT-HB

1,3-Dichlorobenzene

541731

960

320

TT-HB

1,4-Dichlorobenzene

106467

190

63

TT-HB

3,3'-Dibenzidenes

91941

0.028

0.021

C-HB

Diethyl Phthalate

84662

44,000

17,000

TT

Dimethyl Phthalate

131113

1,100,000

270,000

TT

Di-n-butyl Phthlate

84742

4,500

2,000

TT-HB

Di-n-octyl Phthalate ester

117840

2,4-Dinitrotoluene

121142

3.4

0.11

C

2,6-Dinitrotoluene

606202

Di-n-ocytyl phthalate

117840

1,2-Diphenylhydrazine

122667

0.20

0.036

C

Fluoranthene

206440

1.28

1.01

C-HB

Fluorene

86737

49.2

4.37

C-HB

Hexachlorobenzene

118741

0.00029

0.00028

C-HB

Hexachlorobutadiene

87683

18

0.44

C-HB

Hexachlorocyclopentadiene

77474

1,100

40

TT-HB

Hexachloroethane

67721

3.3

1.4

C-HB

Indeno (1,2,3-cd) pyrene

193395

0.018

0.0038

C-HB

Isophorone

78591

960

35

TT

Napthalene

91203

20,513

677

TT

Nitrobenzene

98953

690

17

TT

N-Nitrosodimethylamine

62759

3

0.00069

C

N-Nitrosodi-N-propylamine

621647

0.51

0.005

C

N-Nitrosodiphenylamine

86306

6.0

3.3

C

Phenanthrene

85018

49.17

4.37

C-HB

Pyrene

129000

49.17

4.37

C-HB

1,2,4-Trichlorobenzene

120821

70

35

TT

Pesticides

Aldrin

309002

1.50

0.65

0.00005

0.000049

C-HB

Chlordane

57749

1.20

0.0043

0.045

0.004

0.00081

0.00080

C-HB

DDT

50293

0.5511

0.00111

0.06511

0.00111

0.00022

0.00022

C-HB

DDD

72548

0.00031

0.00031

C-HB

DDE

72559

0.00022

0.00022

C-HB

Dieldrin

60571

0.24

0.056

0.355

0.0019

0.000054

0.000052

C

Endosulfan Alpha

959988

0.1112

0.05612

0.01712

0.008712

89

62

TT

Endosulfan Beta

33213659

0.1112

0.05612

0.01712

0.008712

89

62

TT

Endosulfan Sulfate

1031078

89

62

TT

Endrin

72208

0.086

0.036

0.0185

0.0023

0.060

0.059

TT

Endrin Aldehyde

7421934

0.30

0.29

TT

Heptachlor

76448

0.26

0.0038

0.0265

0.0036

0.000079

0.000079

C

Hetachlor epoxide

1024573

0.26

0.0038

0.0265

0.0036

0.000039

0.000039

C

Hexachlorocyclohexane alpha

319846

0.0049

0.0026

C-HB

Hexachlorocyclohexane beta

319857

0.017

0.0091

C-HB

Hexachlorocyclohexane delta

319868

Hexachlorocyclohexane gamma (Lindane)

58899

0.95

0.08

0.063

0.019

TT-HB

Polychlorinated Biphenyls13

0.014

0.03

0.000064

0.000064

C-HB

2,3,7,8-TCDD (Dioxin)

1746016

0.0000000051

0.000000005

C-HB

Toxaphene

8001352

0.73

0.0002

0.21

0.0002

0.00028

0.00028

C-HB

Other Susbstances

Aluminum

7429905

750

87

Ammonia

7664417

*

**

233 15

35 15

Asbestos

1332214

7 Million fibers per liter

A

Chlorine

7782505

19

11

13

7.5

Chloride

16887006

860,000

230,000

*See Table Note 14-A

**See Table Notes 14B & 14C

Table 3 - Notes:

1. The minimum data necessary to determine consistency with Connecticut Water Quality Standards shall be subject to the Commissioner's discretion and may not be limited to or include chemical analysis results for all of the constituents listed in Table 3.

2. Aquatic life criteria for freshwater may be used for saltwater if criteria for saltwater is unavailable.

3. For brackish waters, use the more restrictive of the aquatic life criteria for freshwater and for saltwater.

4. Biological integrity is impaired by an exposure of one hour or longer to a concentration which exceeds the acute criteria more frequently than once every three years on average.

5. Biological integrity is impaired when the four-day average concentration exceeds the chronic criteria more frequently than once every three years on average.

6. The commissioner shall consider the following human health designations in allocating zones of influence for discharges:

A: Class A carcinogen (known human carcinogen)

TT: Threshold Toxicant, not carcinogenic

C: Carcinogenic (probable or possible carcinogen)

HB: High potential to bioaccumulate or bioconcentrate

7. Criteria apply to the dissolved fraction of ambient waters unless otherwise noted.

8. Biological integrity is impaired when the ambient concentration exceeds this value on more than 5% of days in any year.

9. Biological integrity is impaired when the ambient concentration exceeds this value on more than 50% of days in any year.

10. Site-specific criteria for copper apply for the following waters:

Bantam River Litchfield POTW to confluence with Shepaug River

Blackberry River Norfolk POTW to confluence with Roaring Brook

North Canaan POTW to confluence with Housatonic River

Factory Brook Salisbury POTW to mouth

Five Mile River New Canaan POTW to mouth

Hockanum River Vernon POTW to confluence with Connecticut River

Mill Brook Plainfield Village POTW to mouth

Naugatuck River Torrington POTW to confluence with Housatonic River

Norwalk River Ridgefield Brook to Branchville

Pequabuck River Plymouth POTW to confluence with Farmington River

Pootatuck River Newtown POTW to confluence with the Housatonic River

Quinnipiac River Southington POTW to Broadway, North Haven

Still River Winsted POTW to confluence with Farmington River

Still River Limekiln Brook to confluence with Housatonic River

Williams Brook Ledyard POTW to mouth

Willimantic River Stafford Springs POTW to Trout Management Area (Willington)

Eagleville Dam to confluence with Shetucket River

11. This criterion applies to DDT and its metabolites (i.e. the total concentration of DDT and its metabolites should not exceed this value).

12. This value was derived from data for endosulfan and is most appropriately applied to the sum of alpha endosulfan and beta endosulfan.

13. Criteria are applicable to total PCB's (e.g. the sum of all congeners or all isomer or homolog or Arochor analyses).

14. Criteria for ammonia, (mg/l as N) vary in response to ambient surface water temperature (T, degrees C) and pH. Biological integrity is considered impaired when:

A The one-hour average concentration of total ammonia exceeds:

[0.275/(1+10(7.204-pH))] + [39.0/(1+10(pH-7.204))] when salmonids are present

Or

[0.411/(1+10(7.204-pH))] + [58.4/(1+10(pH-7.204))] when salmonids are absent

B The four-day average concentration of total ammonia exceeds 2.5 times the value obtained from the formula in 14.C. below.

C The 30-day average concentration of total ammonia exceeds:

[0.0577/(1+10(7.688-pH))] + [2.487/(1+10(pH-7.688))] x [MIN(2.85, 1.45 x (10(0.028(25-T)))]

when early life stages are present;

or

[0.0577/(1+10(7.688-pH))] + [2.487/(1+10(pH-7.688))] x [1.45 x (10(0.028(25-MAX(T,7)))]

when early life stages are absent.

15. Saltwater ammonia criteria are expressed as un-ionized ammonia (NH3). Equivalent total ammonia concentrations are dependent on receiving water temperature, pH, and salinity.

Conversion of un-unionized ammonia concentrations to total ammonia (NH3 + NH4+) may be performed using the procedure described in "Ambient Water Quality Criteria for Ammonia (Saltwater) - 1989", EPA 440/5-88-004.

(b) Ground Water Quality Criteria

(1) In areas classified as GAA, GAAs, and GA:
(A) dissolved oxygen, pH, and chemical constituents shall be maintained at levels as naturally occur; and

(B) oils and grease, color and turbidity, taste and odor, and coliform bacteria shall not be present unless of natural origin.

(2) In areas classified as GB, no specific ground water quality criteria apply except those that may be promulgated as part of the Site Remediation Regulations adopted pursuant to section 22a-133k of the Connecticut General Statutes.

(3) In areas classified as GC, no quantitative criteria are specifically determined until such time as a person applies to the department under section 22a-430 of the Connecticut General Statutes to discharge leachate to ground water.

Disclaimer: These regulations may not be the most recent version. Connecticut may have more current or accurate information. We make no warranties or guarantees about the accuracy, completeness, or adequacy of the information contained on this site or the information linked to on the state site. Please check official sources.
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