Minn. R. agency 167, ch. 7050, WATER QUALITY STANDARDS FOR PROTECTION OF WATERS OF THE STATE, pt. 7050.0220

Current through Register Vol. 49, No. 24, December 9, 2024

Part 7050.0220 - SPECIFIC WATER QUALITY STANDARDS BY ASSOCIATED USE CLASSES

Subpart 1.Purpose and scope. The numeric and narrative water quality standards in this chapter prescribe the qualities or properties of the waters of the state that are necessary for the designated public uses and benefits. If the standards in this chapter are exceeded, it is considered indicative of a polluted condition that is actually or potentially deleterious, harmful, detrimental, or injurious with respect to designated uses or established classes of the waters of the state.

All surface waters are protected for multiple beneficial uses. Numeric water quality standards are tabulated in this part for all uses applicable to four common categories of surface waters, so that all applicable standards for each category are listed together in subparts 3a to 6a. The four categories are:

A. cold water aquatic life and habitat, also protected for drinking water: classes 1B; 2A, 2Ae, or 2Ag; 3; 4A and 4B; and 5 (subpart 3a);

B. cool and warm water aquatic life and habitat, also protected for drinking water: classes 1B or 1C; 2Bd, 2Bde, 2Bdg, or 2Bdm; 3; 4A and 4B; and 5 (subpart 4a);

C. cool and warm water aquatic life and habitat and wetlands: classes 2B, 2Be, 2Bg, 2Bm, or 2D; 3; 4A and 4B; and 5 (subpart 5a); and

D. limited resource value waters: classes 3; 4A and 4B; 5; and 7 (subpart 6a).

Subp. 2.Explanation of tables.

A. Class 1 domestic consumption (DC) standards are the United States Environmental Protection Agency primary (maximum contaminant levels) and secondary drinking water standards, as contained in Code of Federal Regulations, title 40, parts 141 and 143, as amended through July 1, 2006. The DC standards are listed in subparts 3a and 4a, except that individual pollutants, substances, or organisms in the treatment technological, disinfectants, microbiological, and radiological categories are not listed unless they are listed because a secondary drinking water standard or a standard for another use class exists.

B. Certain drinking water standards are not applicable to Class 1 waters. The following are not applicable to Class 1 surface waters: the primary drinking water standards for acrylamide, epichlorohydrin, copper, lead, and turbidity (treatment technique standards) and the standards in the disinfectants and microbiological organisms categories. The drinking water standards not applicable to Class 1 ground waters are listed in part 7050.0221.

C. Class 2 standards for metals are expressed as total metal in subparts 3a to 5a, but must be converted to dissolved metal standards for application to surface waters. Conversion factors for converting total metal standards to dissolved metal standards are listed in part 7050.0222, subpart 9. The conversion factor for metals not listed in part 7050.0222, subpart 9, is one. The dissolved metal standard equals the total metal standard times the conversion factor. Water quality-based effluent limits for metals are expressed as total metal.

D. The tables of standards in subparts 3a to 6a include the following abbreviations and acronyms:

AN	means aesthetic enjoyment and navigation, class 5 waters
*	an asterisk following the FAV and MS values or double dashes (--) means part 7050.0222, subpart 7, item G, applies
(c)	means the chemical is assumed to be a human carcinogen
CS	means chronic standard, defined in part 7050.0218, subpart 3
DC	means domestic consumption (drinking water), class 1 waters
--	double dashes means there is no standard
exp. ()	means the natural antilogarithm (base e) of the expression in parenthesis
FAV	means final acute value, defined in part 7050.0218, subpart 3
IR	means agriculture irrigation use, class 4A waters
LS	means agriculture livestock and wildlife use, class 4B waters
MS	means maximum standard, defined in part 7050.0218, subpart 3
NA	means not applicable
(S)	means the associated value is a secondary drinking water standard
su	means standard unit. It is the reporting unit for pH
TH	means total hardness in mg/L, which is the sum of the calcium and magnesium concentrations expressed as CaCO₃
TON	means threshold odor number

E. Important synonyms or acronyms for some chemicals are listed in parentheses below the primary name.

F. When two or more use classes have standards for the same pollutant, the most stringent standard applies. All surface waters are protected for classes 3 and 6, but these classes have no numeric standards so they are not included in the tables.

G. Certain waters are protected for wild rice, and a numeric standard for sulfates applies according to part 7050.0224, subpart 2.

Subp. 3. [Repealed, 24 SR 1105]

Subp. 3a.Cold water aquatic life and habitat, drinking water, and associated use classes.

Water quality standards applicable to use classes 1B; 2A, 2Ae, or 2Ag; 3; 4A and 4B; and 5 surface waters. The water quality standards in part 7050.0222, subpart 2, that apply to class 2A also apply to classes 2Ae and 2Ag. In addition to the water quality standards in part 7050.0222, subpart 2, the biological criteria defined in part 7050.0222, subpart 2d, apply to classes 2Ae and 2Ag.

A. MISCELLANEOUS SUBSTANCE, CHARACTERISTIC, OR POLLUTANT

FAV

(1) Ammonia, un-ionized as N, µg/L

(2) Asbestos, >10 µm (c), fibers/L

7.0e+06

(3) Bromate, µg/L

(4) Chloride, mg/L

230

860

1,720

250(S)

FAV

(5) Chlorine, total residual, µg/L

(6) Chlorite, µg/L

1,000

(7) Color, Pt-Co

15(S)

(8) Cyanide, free, µg/L

5.2

200

(9) Escherichia (E.) coli bacteria, organisms/100 mL

See item D

FAV

(10) Eutrophication standards for lakes and reservoirs (phosphorus, total, µg/L; chlorophyll-a, µg/L; Secchi disk transparency, meters)

See part 7050.0222, subparts 2 and 2a

(11) Eutrophication standards for rivers, streams, and navigational pools (phosphorus, total µg/L; chlorophyll-a (seston), µg/L; five-day biochemical oxygen demand (BOD₅), mg/L; diel dissolved oxygen flux, mg/L; chlorophyll-a (periphyton), mg/m²)

See part 7050.0222, subparts 2 and 2b

(12) Fluoride, mg/L

(13) Fluoride, mg/L

2(S)

(14) Foaming agents, µg/L

500(S)

FAV

(15) Hydrogen sulfide, mg/L

0.02

(16) Nitrate as N, mg/L

(17) Nitrite as N, mg/L

(18) Nitrate + Nitrite as N, mg/L

100

(19) Odor, TON

3(S)

FAV

(20) Oil, µg/L

500

5,000

10,000

(21) Oxygen, dissolved, mg/L

7, as a daily minimum

(22) pH minimum, su

6.5

6.5(S)

6.0

(23) pH maximum, su

8.5

8.5(S)

9.0

(24) Radioactive materials

See item E

FAV

(25) Sulfate, mg/L

250(S)

600

(26) Sulfates, wild rice present, mg/L

FAV

(27) Temperature, °F

No material increase

(28) Total dissolved solids, mg/L

500(S)

3,000

(29) Total suspended solids (TSS), mg/L

See part 7050.0222, subpart 2

B. METALS AND ELEMENTS

FAV

(1) Aluminum, total, µg/L

748

1,496

50-200(S)

(2) Antimony, total, µg/L

5.5

180

(3) Arsenic, total, µg/L

2.0

360

720

(4) Barium, total, µg/L

2,000

(5) Beryllium, total, µg/L

4.0

2ACS

2AMS

2AFAV

1BDC

4AIR

4BLS

5AN

(6) Boron, total, µg/L

500

(7) Cadmium, total, µg/L

1.1

3.9

7.8

Class 2A cadmium standards are hardness dependent. Cadmium values shown are for a total hardness of 100 mg/L only. See part 7050.0222, subpart 2, for examples at other hardness values and equations to calculate cadmium standards for any hardness value not to exceed 400 mg/L.

(8) Chromium +3, total, µg/L

207

1,737

3,469

Class 2A trivalent chromium standards are hardness dependent. Chromium +3 values shown are for a total hardness of 100 mg/L only. See part 7050.0222, subpart 2, for examples at other hardness values and equations to calculate trivalent chromium standards for any hardness value not to exceed 400 mg/L.

(9) Chromium +6, total, µg/L

(10) Chromium, total, µg/L

100

FAV

(11) Cobalt, total, µg/L

2.8

436

872

(12) Copper, total, µg/L

9.8

1,000(S)

Class 2A copper standards are hardness dependent. Copper values shown are for a total hardness of 100 mg/L only. See part 7050.0222, subpart 2, for examples at other hardness values and equations to calculate copper standards for any hardness value not to exceed 400 mg/L.

(13) Iron, total, µg/L

300(S)

(14) Lead, total, µg/L

3.2

164

Class 2A lead standards are hardness dependent. Lead values shown are for a total hardness of 100 mg/L only. See part 7050.0222, subpart 2, for examples at other hardness values and equations to calculate lead standards for any hardness value not to exceed 400 mg/L.

(15) Manganese, total, µg/L

50(S)

FAV

(16) Mercury, total, in water, ng/L

6.9

2,400*

4,900*

2,000

(17) Mercury, total in edible fish tissue, mg/kg or parts per million

0.2

(18) Nickel, total, µg/L

158

1,418

2,836

Class 2A nickel standards are hardness dependent. Nickel values shown are for a total hardness of 100 mg/L only. See part 7050.0222, subpart 2, for examples at other hardness values and equations to calculate nickel standards for any hardness value not to exceed 400 mg/L.

(19) Selenium, total, µg/L

5.0

(20) Silver, total, µg/L

0.12

2.0

4.1

100(S)

Class 2A silver MS and FAV are hardness dependent. Silver values shown are for a total hardness of 100 mg/L only. See part 7050.0222, subpart 2, for examples at other hardness values and equations to calculate silver standards for any hardness value not to exceed 400 mg/L.

FAV

(21) Thallium, total, µg/L

0.28

128

(22) Zinc, total, µg/L

106

117

234

5,000(S)

Class 2A zinc standards are hardness dependent. Zinc values shown are for a total hardness of 100 mg/L only. See part 7050.0222, subpart 2, for examples at other hardness values and equations to calculate zinc standards for any hardness value not to exceed 400 mg/L.

C. ORGANIC POLLUTANTS OR CHARACTERISTICS

FAV

(1) Acenaphthene, µg/L

112

(2) Acetochlor, µg/L

3.6

173

(3) Acrylonitrile (c), µg/L

0.38

1,140*

2,281*

(4) Alachlor (c), µg/L

3.8

800*

1,600*

(5) Aldicarb, µg/L

FAV

(6) Aldicarb sulfone, µg/L

(7) Aldicarb sulfoxide, µg/L

(8) Anthracene, µg/L

0.035

0.32

0.63

(9) Atrazine (c), µg/L

3.4

323

645

(10) Benzene (c), µg/L

5.1

4,487*

8,974*

FAV

(11) Benzo(a)pyrene, µg/L

0.2

(12) Bromoform, µg/L

2,900

5,800

See subitem (73)

(13) Carbofuran, µg/L

(14) Carbon tetrachloride (c), µg/L

1.9

1,750*

3,500*

(15) Chlordane (c), ng/L

0.073

1,200*

2,400*

2,000

FAV

(16) Chlorobenzene, µg/L (Monochlorobenzene)

423

846

100

(17) Chloroform (c), µg/L

1,392

2,784

See subitem (73)

(18) Chlorpyrifos, µg/L

0.041

0.083

0.17

(19) Dalapon, µg/L

200

(20) DDT (c), ng/L

0.11

550*

1,100*

FAV

(21) 1,2-Dibromo-3-chloropropane (c), µg/L

0.2

(22) Dichlorobenzene (ortho), µg/L

600

(23) 1,4-Dichlorobenzene (para) (c), µg/L

(24) 1,2-Dichloroethane (c), µg/L

3.5

45,050*

90,100*

(25) 1,1-Dichloroethylene, µg/L

FAV

(26) 1,2-Dichloroethylene (cis), µg/L

(27) 1,2-Dichloroethylene (trans), µg/L

100

(28) 2,4-Dichlorophenoxyacetic acid (2,4-D), µg/L

(29) 1,2-Dichloropropane (c), µg/L

(30) Dieldrin (c), ng/L

0.0065

1,300*

2,500*

FAV

(31) Di-2-ethylhexyl adipate, µg/L

400

(32) Di-2-ethylhexyl phthalate (c), µg/L

1.9

--*

(33) Di-n-Octyl phthalate, µg/L

825

1,650

(34) Dinoseb, µg/L

(35) Diquat, µg/L

FAV

(36) Endosulfan, µg/L

0.0076

0.084

0.17

(37) Endothall, µg/L

100

(38) Endrin, µg/L

0.0039

0.090

0.18

(39) Ethylbenzene (c), µg/L

1,859

3,717

700

(40) Ethylene dibromide, µg/L

0.05

2ACS

2AMS

2AFAV

1BDC

4AIR

4BLS

5AN

(41) Fluoranthene, µg/L

1.9

3.5

6.9

(42) Glyphosate, µg/L

700

(43) Haloacetic acids (c), µg/L (Bromoacetic acid, Dibromoacetic acid, Dichloroacetic acid, Monochloroacetic acid, and Trichloroacetic acid)

(44) Heptachlor (c), ng/L

0.10

260*

520*

400

(45) Heptachlor epoxide (c), ng/L

0.12

270*

530*

200

FAV

(46) Hexachlorobenzene (c), ng/L

0.061

--*

1,000

(47) Hexachlorocyclopentadiene, µg/L

(48) Lindane (c), µg/L (Hexachlorocyclohexane, gamma-)

0.0087

1.0*

2.0*

0.2

(49) Methoxychlor, µg/L

(50) Methylene chloride (c), µg/L (Dichloromethane)

13,875*

27,749*

FAV

(51) Metolachlor

271

543

(52) Naphthalene, µg/L

409

818

(53) Oxamyl, µg/L (Vydate)

200

(54) Parathion, µg/L

0.013

0.07

0.13

(55) Pentachlorophenol, µg/L

0.93

Class 2A MS and FAV are pH dependent. Pentachlorophenol values shown are for a pH of 7.5 only. See part 7050.0222, subpart 2, for examples at other pH values and equations to calculate pentachlorophenol standards for any pH value.

FAV

(56) Phenanthrene, µg/L

3.6

(57) Phenol, µg/L

123

2,214

4,428

(58) Picloram, µg/L

500

(59) Polychlorinated biphenyls (c), ng/L (PCBs, total)

0.014

1,000*

2,000*

500

(60) Simazine, µg/L

FAV

(61) Styrene (c), µg/L

100

(62) 2,3,7,8-Tetrachlorodibenzo-p-dioxin, ng/L (TCDD-dioxin)

0.03

(63) 1,1,2,2-Tetrachloroethane (c), µg/L

1.1

1,127*

2,253*

(64) Tetrachloroethylene (c), µg/L

3.8

428*

857*

(65) Toluene, µg/L

253

1,352

2,703

1,000

FAV

(66) Toxaphene (c), ng/L

0.31

730*

1,500*

3,000

(67) 2,4,5-TP, µg/L (Silvex)

(68) 1,2,4-Trichlorobenzene, µg/L

(69) 1,1,1-Trichloroethane, µg/L

329

2,957

5,913

200

(70) 1,1,2-Trichloroethane, µg/L

FAV

(71) 1,1,2-Trichloroethylene (c), µg/L

6,988

13,976*

(72) 2,4,6-Trichlorophenol, µg/L

2.0

102

203

(73) Trihalomethanes, total (c), µg/L (Bromodichloromethane, Bromoform, Chlorodibromomethane, and Chloroform)

(74) Vinyl chloride (c), µg/L

0.17

--*

(75) Xylenes, total, µg/L

166

1,407

2,814

10,000

D.Escherichia (E.) coli bacteria shall not exceed 126 organisms per 100 milliliters as a geometric mean of not less than five samples representative of conditions within any calendar month, nor shall more than ten percent of all samples taken during any calendar month individually exceed 1,260 organisms per 100 milliliters. The standard applies only between April 1 and October 31.

E. For radioactive materials, see parts 7050.0221, subpart 2; 7050.0222, subpart 2; and 7050.0224, subparts 2 and 3.

Subp. 4. [Repealed, 24 SR 1105]

Subp. 4a.Cool and warm water aquatic life and habitat, drinking water, and associated use classes.

Water quality standards applicable to use classes 1B or 1C; 2Bd, 2Bde, 2Bdg, or 2Bdm; 3; 4A and 4B; and 5 surface waters. The water quality standards in part 7050.0222, subpart 3, that apply to class 2Bd also apply to classes 2Bde, 2Bdg, and 2Bdm. In addition to the water quality standards in part 7050.0222, subpart 3, the biological criteria defined in part 7050.0222, subpart 3d, apply to classes 2Bde, 2Bdg, and 2Bdm.

A. MISCELLANEOUS SUBSTANCE, CHARACTERISTIC, OR POLLUTANT

2Bd

FAV

1B/1C

(1) Ammonia, un-ionized as N, µg/L

(2) Asbestos, >10 µm (c), fibers/L

7.0e+06

(3) Bromate, µg/L

(4) Chloride, mg/L

230

860

1,720

250(S)

2Bd

FAV

1B/1C

(5) Chlorine, total residual, µg/L

(6) Chlorite, µg/L

1,000

(7) Color, Pt-Co

15(S)

(8) Cyanide, free, µg/L

5.2

200

(9) Escherichia (E.) coli bacteria, organisms/100 mL

See item D

2Bd

FAV

1B/1C

(10) Eutrophication standards for lakes, shallow lakes, and reservoirs (phosphorus, total, µg/L; chlorophyll-a, µg/L; Secchi disk transparency, meters)

See part 7050.0222, subparts 3 and 3a

See part 7050.0222, subparts 3 and 3b

(12) Fluoride, mg/L

(13) Fluoride, mg/L

2(S)

(14) Foaming agents, µg/L

500(S)

2Bd

FAV

1B/1C

(15) Hydrogen sulfide, mg/L

0.02

(16) Nitrate as N, mg/L

(17) Nitrite as N, mg/L

(18) Nitrate + Nitrite as N, mg/L

100

(19) Odor, TON

3(S)

2Bd

FAV

1B/1C

(20) Oil, µg/L

500

5,000

10,000

(21) Oxygen, dissolved, mg/L

See part 7050.0222, subpart 3

(22) pH minimum, su

6.5

6.5(S)

6.0

(23) pH maximum, su

9.0

8.5(S)

9.0

(24) Radioactive materials

See item E

2Bd

FAV

1B/1C

(25) Sulfate, mg/L

250(S)

600

(26) Sulfates, wild rice present, mg/L

2Bd

FAV

1B/1C

(27) Temperature, °F

See item F

(28) Total dissolved solids, mg/L

500(S)

3,000

(29) Total suspended solids (TSS), mg/L

See part 7050.0222, subpart 3

B. METALS AND ELEMENTS

2Bd

FAV

1B/1C

(1) Aluminum, total, µg/L

125

1,072

2,145

50-200(S)

(2) Antimony, total, µg/L

5.5

180

(3) Arsenic, total, µg/L

2.0

360

720

(4) Barium, total, µg/L

2,000

(5) Beryllium, total, µg/L

4.0

2Bd

FAV

1B/1C

(6) Boron, total, µg/L

500

(7) Cadmium, total, µg/L

1.1

Class 2Bd cadmium standards are hardness dependent. Cadmium values shown are for a total hardness of 100 mg/L only. See part 7050.0222, subpart 3, for examples at other hardness values and equations to calculate cadmium standards for any hardness value not to exceed 400 mg/L.

(8) Chromium +3, total, µg/L

207

1,737

3,469

Class 2Bd trivalent chromium standards are hardness dependent. Chromium +3 values shown are for a total hardness of 100 mg/L only. See part 7050.0222, subpart 3, for examples at other hardness values and equations to calculate trivalent chromium standards for any hardness value not to exceed 400 mg/L.

(9) Chromium +6, total, µg/L

(10) Chromium, total, µg/L

100

2Bd

FAV

1B/1C

(11) Cobalt, total, µg/L

2.8

436

872

(12) Copper, total, µg/L

9.8

1,000(S)

Class 2Bd copper standards are hardness dependent. Copper values shown are for a total hardness of 100 mg/L only. See part 7050.0222, subpart 3, for examples at other hardness values and equations to calculate copper standards for any hardness value not to exceed 400 mg/L.

(13) Iron, total, µg/L

300(S)

(14) Lead, total, µg/L

3.2

164

Class 2Bd lead standards are hardness dependent. Lead values shown are for a total hardness of 100 mg/L only. See part 7050.0222, subpart 3, for examples at other hardness values and equations to calculate lead standards for any hardness value not to exceed 400 mg/L.

(15) Manganese, total, µg/L

50(S)

2Bd

FAV

1B/1C

(16) Mercury, total in water, ng/L

6.9

2,400*

4,900*

2,000

(17) Mercury, total in edible fish tissue, mg/kg or parts per million

0.2

(18) Nickel, total, µg/L

158

1,418

2,836

Class 2Bd nickel standards are hardness dependent. Nickel values shown are for a total hardness of 100 mg/L only. See part 7050.0222, subpart 3, for examples at other hardness values and equations to calculate nickel standards for any hardness value not to exceed 400 mg/L.

(19) Selenium, total, µg/L

5.0

(20) Silver, total, µg/L

1.0

2.0

4.1

100(S)

Class 2Bd silver MS and FAV are hardness dependent. Silver values shown are for a total hardness of 100 mg/L only. See part 7050.0222, subpart 3, for examples at other hardness values and equations to calculate silver standards for any hardness value not to exceed 400 mg/L.

2Bd

FAV

1B/1C

(21) Thallium, total, µg/L

0.28

128

(22) Zinc, total, µg/L

106

117

234

5,000(S)

Class 2Bd zinc standards are hardness dependent. Zinc values shown are for a total hardness of 100 mg/L only. See part 7050.0222, subpart 3, for examples at other hardness values and equations to calculate zinc standards for any hardness value not to exceed 400 mg/L.

C. ORGANIC POLLUTANTS OR CHARACTERISTICS

2Bd

FAV

1B/1C

(1) Acenaphthene, µg/L

112

(2) Acetochlor, µg/L

3.6

173

(3) Acrylonitrile (c), µg/L

0.38

1,140*

2,281*

(4) Alachlor (c), µg/L

4.2

800*

1,600*

(5) Aldicarb, µg/L

2Bd

FAV

1B/1C

(6) Aldicarb sulfone, µg/L

(7) Aldicarb sulfoxide, µg/L

(8) Anthracene, µg/L

0.035

0.32

0.63

(9) Atrazine (c), µg/L

3.4

323

645

(10) Benzene (c), µg/L

6.0

4,487*

8,974*

2Bd

FAV

1B/1C

(11) Benzo(a)pyrene, µg/L

0.2

(12) Bromoform, µg/L

2,900

5,800

See sub item (73)

(13) Carbofuran, µg/L

(14) Carbon tetrachloride (c), µg/L

1.9

1,750*

3,500*

(15) Chlordane (c), ng/L

0.29

1,200*

2,400*

2,000

2Bd

FAV

1B/1C

(16) Chlorobenzene, µg/L (Monochlorobenzene)

423

846

100

(17) Chloroform (c), µg/L

1,392

2,784

See sub item (73)

(18) Chlorpyrifos, µg/L

0.041

0.083

0.17

(19) Dalapon, µg/L

200

(20) DDT (c), ng/L

1.7

550*

1,100*

2Bd

FAV

1B/1C

(21) 1,2-Dibromo-3-chloropropane (c), µg/L

0.2

(22) Dichlorobenzene (ortho), µg/L

600

(23) 1,4-Dichlorobenzene (para) (c), µg/L

(24) 1,2-Dichloroethane (c), µg/L

3.8

45,050*

90,100*

(25) 1,1-Dichloroethylene, µg/L

2Bd

FAV

1B/1C

(26) 1,2-Dichloroethylene (cis), µg/L

(27) 1,2-Dichloroethylene (trans), µg/L

100

(28) 2,4-Dichlorophenoxyacetic acid (2,4-D), µg/L

(29) 1,2-Dichloropropane (c), µg/L

(30) Dieldrin (c), ng/L

0.026

1,300*

2,500*

2Bd

FAV

1B/1C

(31) Di-2-ethylhexyl adipate, µg/L

400

(32) Di-2-ethylhexyl phthalate (c), µg/L

1.9

--*

(33) Di-n-Octyl phthalate, µg/L

825

1,650

(34) Dinoseb, µg/L

(35) Diquat, µg/L

2Bd

FAV

1B/1C

(36) Endosulfan, µg/L

0.029

0.28

0.56

(37) Endothall, µg/L

100

(38) Endrin, µg/L

0.016

0.090

0.18

(39) Ethylbenzene (c), µg/L

1,859

3,717

700

(40) Ethylene dibromide, µg/L

0.05

2Bd

FAV

1B/1C

(41) Fluoranthene, µg/L

1.9

3.5

6.9

(42) Glyphosate, µg/L

700

(43) Haloacetic acids (c), µg/L (Bromoacetic acid, Dibromoacetic acid, Dichloroacetic acid, Monochloroacetic acid, and Trichloroacetic acid)

(44) Heptachlor (c), ng/L

0.39

260*

520*

400

(45) Heptachlor epoxide (c), ng/L

0.48

270*

530*

200

2Bd

FAV

1B/1C

(46) Hexachlorobenzene (c), ng/L

0.24

--*

1,000

(47) Hexachlorocyclopentadiene, µg/L

(48) Lindane (c), µg/L (Hexachlorocyclohexane, gamma-)

0.032

4.4*

8.8*

0.2

(49) Methoxychlor, µg/L

(50) Methylene chloride (c), µg/L (Dichloromethane)

13,875*

27,749*

2Bd

FAV

1B/1C

(51) Metolachlor

271

543

(52) Naphthalene, µg/L

409

818

(53) Oxamyl, µg/L (Vydate)

200

(54) Parathion, µg/L

0.013

0.07

0.13

(55) Pentachlorophenol, µg/L

1.9

Class 2Bd MS and FAV are pH dependent. Pentachlorophenol values shown are for a pH of 7.5 only. See part 7050.0222, subpart 3, for examples at other pH values and equations to calculate pentachlorophenol standards for any pH value.

2Bd

FAV

1B/1C

(56) Phenanthrene, µg/L

3.6

(57) Phenol, µg/L

123

2,214

4,428

(58) Picloram, µg/L

500

(59) Polychlorinated biphenyls (c), ng/L (PCBs, total)

0.029

1,000*

2,000*

500

(60) Simazine, µg/L

2Bd

FAV

1B/1C

(61) Styrene (c), µg/L

100

(62) 2,3,7,8-Tetrachlorodibenzo-p-dioxin, ng/L (TCDD-dioxin)

0.03

(63) 1,1,2,2-Tetrachloroethane (c), µg/L

1.5

1,127*

2,253*

(64) Tetrachloroethylene (c), µg/L

3.8

428*

857*

(65) Toluene, µg/L

253

1,352

2,703

1,000

2Bd

FAV

1B/1C

(66) Toxaphene (c), ng/L

1.3

730*

1,500*

3,000

(67) 2,4,5-TP, µg/L (Silvex)

(68) 1,2,4-Trichlorobenzene, µg/L

(69) 1,1,1-Trichloroethane, µg/L

329

2,957

5,913

200

(70) 1,1,2-Trichloroethane, µg/L

2Bd

FAV

1B/1C

(71) 1,1,2-Trichloroethylene (c), µg/L

6,988*

13,976*

(72) 2,4,6-Trichlorophenol, µg/L

2.0

102

203

(73) Trihalomethanes, total (c), µg/L (Bromodichloromethane, Bromoform, Chlorodibromomethane, and Chloroform)

(74) Vinyl chloride (c), µg/L

0.18

--*

(75) Xylenes, total, µg/L

166

1,407

2,814

10,000

E. For radioactive materials, see parts 7050.0221, subpart 3; 7050.0222, subpart 3; and 7050.0224, subparts 2 and 3.

F. Temperature must not exceed five degrees Fahrenheit above natural in streams and three degrees Fahrenheit above natural in lakes, based on monthly average of maximum daily temperature, except in no case shall it exceed the daily average temperature of 86 degrees Fahrenheit.

Subp. 5. [Repealed, 24 SR 1105]

Subp. 5a.Cool and warm water aquatic life and habitat and associated use classes.

Water quality standards applicable to use classes 2B, 2Be, 2Bg, 2Bm, or 2D; 3; 4A and 4B; and 5 surface waters. See part 7050.0225, subpart 2, for class 3 and 5 standards applicable to wetlands. The water quality standards in part 7050.0222, subpart 4, that apply to class 2B also apply to classes 2Be, 2Bg, and 2Bm. In addition to the water quality standards in part 7050.0222, subpart 4, the biological criteria defined in part 7050.0222, subpart 4d, apply to classes 2Be, 2Bg, and 2Bm.

A. MISCELLANEOUS SUBSTANCE, CHARACTERISTIC, OR POLLUTANT

2B&D

2B&D FAV

(1) Ammonia, un-ionized as N, µg/L

(2) Chloride, mg/L

230 See item F

860

1,720

(3) Chlorine, total residual, µg/L

(4) Cyanide, free, µg/L

5.2

2B&D

FAV

(5) Escherichia (E.) coli bacteria, organisms/100 mL

See item D

(6) Eutrophication standards for lakes, shallow lakes, and reservoirs (phosphorus, total, µg/L; chlorophyll-a, µg/L; Secchi disk transparency, meters)

See part 7050.0222, subparts 4 and 4a

(7) Eutrophication standards for rivers, streams, and navigational pools (phosphorus, total µg/L; chlorophyll-a (seston), µg/L; five-day biochemical oxygen demand (BOD₅), mg/L; diel dissolved oxygen flux, mg/L; chlorophyll-a (periphyton), mg/m²)

See part 7050.0222, subparts 4 and 4b

(8) Hydrogen sulfide, mg/L

0.02

(9) Nitrate + nitrite as N, mg/L

100

(10) Oil, µg/L

500

5,000

10,000

2B&D

FAV

(11) Oxygen, dissolved, mg/L

See part 7050.0222, subparts 4 and 6

(12) pH minimum, su

6.5 See item E

6.0

(13) pH maximum, su

9.0 See item E

9.0

(14) Radioactive materials

See item G

Seeitem G

2B&D

FAV

(15) Settleable solids, mL/L

See part 7050.0222, subpart 6

(16) Sulfates, wild rice present, mg/L

(17) Sulfate, mg/L

600

(18) Temperature, °F

See item H

(19) Total dissolved solids, mg/L

3,000

(20) Total suspended solids (TSS), mg/L

See part 7050.0222, subpart 4

B. METALS AND ELEMENTS

2B&D

FAV

(1) Aluminum, total, µg/L

125

1,072

2,145

(2) Antimony, total, µg/L

180

(3) Arsenic, total, µg/L

360

720

(4) Boron, total, µg/L

500

(5) Cadmium, total, µg/L

1.1

Class 2B and 2D cadmium standards are hardness dependent. Cadmium values shown are for a total hardness of 100 mg/L only. See part 7050.0222, subpart 4, for examples at other hardness values and equations to calculate cadmium standards for any hardness value not to exceed 400 mg/L.

2B&D

FAV

(6) Chromium +3, total, µg/L

207

1,737

3,469

Class 2B and 2D trivalent chromium standards are hardness dependent. Chromium +3 values shown are for a total hardness of 100 mg/L only. See part 7050.0222, subpart 4, for examples at other hardness values and equations to calculate trivalent chromium standards for any hardness value not to exceed 400 mg/L.

(7) Chromium +6, total, µg/L

(8) Cobalt, total, µg/L

5.0

436

872

(9) Copper, total, µg/L

9.8

Class 2B and 2D copper standards are hardness dependent. Copper values shown are for a total hardness of 100 mg/L only. See part 7050.0222, subpart 4, for examples at other hardness values and equations to calculate copper standards for any hardness value not to exceed 400 mg/L.

(10) Lead, total, µg/L

3.2

164

Class 2B and 2D lead standards are hardness dependent. Lead values shown are for a total hardness of 100 mg/L only. See part 7050.0222, subpart 4, for examples at other hardness values and equations to calculate lead standards for any hardness value not to exceed 400 mg/L.

2B&D

FAV

(11) Mercury, total in water, ng/L

6.9

2,400*

4,900*

(12) Mercury, total in edible fish tissue, mg/kg or parts per million

0.2

(13) Nickel, total, µg/L

158

1,418

2,836

Class 2B and 2D nickel standards are hardness dependent. Nickel values shown are for a total hardness of 100 mg/L only. See part 7050.0222, subpart 4, for examples at other hardness values and equations to calculate nickel standards for any hardness value not to exceed 400 mg/L.

(14) Selenium, total, µg/L

5.0

(15) Silver, total, µg/L

1.0

2.0

4.1

Class 2B and 2D silver MS and FAV are hardness dependent. Silver values shown are for a total hardness of 100 mg/L only. See part 7050.0222, subpart 4, for examples at other hardness values and equations to calculate silver standards for any hardness value not to exceed 400 mg/L.

2B&D

FAV

(16) Thallium, total, µg/L

0.56

128

(17) Zinc, total, µg/L

106

117

234

Class 2B and 2D zinc standards are hardness dependent. Zinc values shown are for a total hardness of 100 mg/L only. See part 7050.0222, subpart 4, for examples at other hardness values and equations to calculate zinc standards for any hardness value not to exceed 400 mg/L.

C. ORGANIC POLLUTANTS OR CHARACTERISTICS

2B&D

FAV

(1) Acenaphthene, µg/L

112

(2) Acetochlor, µg/L

3.6

173

(3) Acrylonitrile (c), µg/L

0.89

1,140*

2,281*

(4) Alachlor (c), µg/L

800

1,600

(5) Anthracene, µg/L

0.035

0.32

0.63

2B&D

FAV

(6) Atrazine (c), µg/L

323

645

(7) Benzene (c), µg/L

4,487

8,974

(8) Bromoform, µg/L

466

2,900

5,800

(9) Carbon tetrachloride (c), µg/L

5.9

1,750*

3,500*

(10) Chlordane (c), ng/L

0.29

1,200*

2,400*

2B&D

FAV

(11) Chlorobenzene, µg/L (Monochlorobenzene)

423

846

(12) Chloroform (c), µg/L

155

1,392

2,78

(13) Chlorpyrifos, µg/L

0.041

0.083

0.17

(14) DDT (c), ng/L

1.7

550*

1,100*

(15) 1,2-Dichloroethane (c), µg/L

190

45,050*

90,100*

2B&D

FAV

(16) Dieldrin (c), ng/L

0.026

1,300*

2,500*

(17) Di-2-ethylhexyl phthalate (c), µg/L

2.1

--*

(18) Di-n-Octyl phthalate, µg/L

825

1,650

(19) Endosulfan, µg/L

0.031

0.28

0.56

(20) Endrin, µg/L

0.016

0.090

0.18

2B&D

FAV

(21) Ethylbenzene (c), µg/L

1,859

3,717

(22) Fluoranthene, µg/L

1.9

3.5

6.9

(23) Heptachlor (c), ng/L

0.39

260*

520*

(24) Heptachlor epoxide (c), ng/L

0.48

270*

530*

(25) Hexachlorobenzene (c), ng/L

0.24

--*

2B&D	2B&D	2B&D	4A	4B	5
CS	MS	FAV	IR	LS	AN

(26) Lindane (c), µg/L (Hexachlorocyclohexane, gamma-)

0.036

4.4*

8.8*

(27) Methylene chloride (c), µg/L (Dichloromethane)

1,940

13,875

27,749

(28) Metolachlor

271

543

(29) Naphthalene, µg/L

409

818

(30) Parathion, µg/L

0.013

0.07

0.13

2B&D

FAV

(31) Pentachlorophenol, µg/L

5.5

Class 2B and 2D standards are pH dependent, except that the CS will not exceed 5.5 µg/L. Pentachlorophenol values shown are for a pH of 7.5 only. See part 7050.0222, subpart 4, for examples at other pH values and equations to calculate pentachlorophenol standards for any pH value.

(32) Phenanthrene, µg/L

3.6

(33) Phenol, µg/L

123

2,214

4,428

(34) Polychlorinated biphenyls (c), ng/L (PCBs, total)

0.029

1,000*

2,000*

(35) 1,1,2,2-Tetrachloroethane (c), µg/L

1,127

2,253

2B&D

FAV

(36) Tetrachloroethylene (c), µg/L

8.9

428

857

(37) Toluene, µg/L

253

1,352

2,703

(38) Toxaphene (c), ng/L

1.3

730*

1,500*

(39) 1,1,1-Trichloroethane, µg/L

329

2,957

5,913

(40) 1,1,2-Trichloroethylene (c), µg/L

120

6,988

13,976

2B&D	2B&D	2B&D	4A	4B	5
CS	MS	FAV	IR	LS	AN

(41) 2,4,6-Trichlorophenol, µg/L

2.0

102

203

(42) Vinyl chloride (c), µg/L

9.2

--*

(43) Xylenes, total, µg/L

166

1,407

2,814

E. For pH, maintain background. See part 7050.0222, subpart 6.

F. For chloride, maintain background if background is greater than the class 2B chloride standard. See part 7050.0222, subpart 6.

G. For radioactive materials, see parts 7050.0222, subpart 4; and 7050.0224, subparts 2 and 3.

H. Temperature must not exceed:

(1) Class 2B standard: five degrees Fahrenheit above natural in streams and three degrees Fahrenheit above natural in lakes, based on monthly average of maximum daily temperature, except in no case shall it exceed the daily average temperature of 86 degrees Fahrenheit; and

(2) Class 2D standard: maintain background as defined in part 7050.0222, subpart 6.

Subp. 6. [Repealed, 24 SR 1105]

Subp. 6a.Limited resource value waters and associated use classes.

A. WATER QUALITY STANDARDS APPLICABLE TO USE CLASSES 3, 4A, 4B, 5, AND 7 SURFACE WATERS

7 LIMITED RESOURCE VALUE

(1) Boron, µg/L

500

(2) Escherichia (E.) coli bacteria, organisms/100 mL

See item B

7 LIMITED RESOURCE VALUE

(3) Hydrogen sulfide, mg/L

0.02

(4) Nitrate + nitrite as N, mg/L

100

(5) Oxygen, dissolved, mg/L

See item C

(6) pH minimum, su

6.0

(7) pH maximum, su

9.0

(8) Radioactive materials

See item D

7 LIMITED RESOURCE VALUE

(9) Sulfate, mg/L

600

(10) Sulfates, wild rice present, mg/L

(11) Total dissolved solids, mg/L

3,000

(12) Toxic pollutants

See item E

B.Escherichia (E.) coli bacteria shall not exceed 630 organisms per 100 milliliters as a geometric mean of not less than five samples representative of conditions within any calendar month, nor shall more than ten percent of all samples taken during any calendar month individually exceed 1,260 organisms per 100 milliliters. The standard applies only between May 1 and October 31.

C. The level of dissolved oxygen shall must be maintained at concentrations:

(1) that will avoid odors or putrid conditions in the receiving water;

(2) at not less than one milligram per liter (daily average); and

(3) above zero milligrams per liter at all times.

D. For radioactive materials, see part 7050.0224, subparts 2 and 3.

E. Toxic pollutants shall not be allowed in such quantities or concentrations that will impair the specified uses.

Subp. 7.Site-specific modifications of standards.

A. The standards in this part and in parts 7050.0221 to 7050.0227 are subject to review and modification as applied to a specific surface water body, reach, or segment. If site-specific information is available that shows that a site-specific modification is more appropriate than the statewide or ecoregion standard for a particular water body, reach, or segment, the site-specific information shall be applied.

B. The information supporting a site-specific modification can be provided by the commissioner or by any person outside the agency. The commissioner shall evaluate all relevant data in support of a modified standard and determine whether a change in the standard for a specific water body or reach is justified.

C. Any effluent limit determined to be necessary based on a modified standard shall only be required after the discharger has been given notice of the specific proposed effluent limits and an opportunity to request a hearing as provided in part 7000.1800.

D. Through the procedures established in items A to C, the following site-specific reservoir eutrophication standards apply to Lake Pepin (25-0001-00) in lieu of the water quality standards listed in this part and part 7050.0222:

(1) Phosphorus, total	µg/L	less than or equal to 100
(2) Chlorophyll-a (seston)	µg/L	less than or equal to 28

Minn. R. agency 167, ch. 7050, WATER QUALITY STANDARDS FOR PROTECTION OF WATERS OF THE STATE, pt. 7050.0220

9 SR 913; 12 SR 1810; 15 SR 1057; 18 SR 2195; 24 SR 1105; 24 SR 1133; 32 SR 1699

39 SR 154

46 SR 5

Statutory Authority: MS s 115.03; 115.44