DEPARTMENT OF ENERGY AND ENVIRONMENT

 

NOTICE OF PROPOSED RULEMAKING

 

Water Quality Standards - 2016 Triennial Review

 

The Director of the Department of Energy and Environment (DOEE or Department), in accordance with the authority set forth in the District Department of the Environment Establishment Act of 2005, effective February 15, 2006 (D.C. Law 16-51; D.C. Official Code
§§ 8-151.01 et seq. (2013 Repl. & 2016 Supp.)); Sections 5 and 21 of the Water Pollution Control Act of 1984, effective March 16, 1985 (D.C. Law 5-188; D.C. Official Code §§ 8-103.04 and 8-103.20 (2013 Repl. & 2016 Supp.)); and Mayor’s Order 98-50, dated April 15, 1998, as amended by Mayor’s Order 2006-61, dated June 14, 2006, hereby gives notice of the proposed rulemaking action to amend Chapter 11 (Water Quality Standards) of Title 21 (Water and Sanitation) of the District of Columbia Municipal Regulations (DCMR).

 

The Department’s Water Quality Division is conducting a triennial review of the District of Columbia’s Water Quality Standards regulations as required by Section 5(a) of the Water Pollution Control Act (D.C. Official Code § 8-103.04(a)) and Section 303(c) of the federal Clean Water Act (33 U.S.C. § 1313(c)).  

 

Proposed changes to the water quality standards include updates to the aquatic life criteria for ammonia and cadmium, and human health criteria for ninety-four (94) constituents.

 

Proposed updates to the ammonia criteria are based on EPA’s latest scientific studies and new toxicity data on freshwater mussels and gill-breathing snails in the 2013 Aquatic Life Ambient Water Quality Criteria for Ammonia – Freshwater, published by EPA (EPA 822-R-13-001). Ammonia can be toxic to fish and other invertebrates in waterbodies.

 

Changes to the aquatic life criteria proposed for cadmium adhere to the 2016 Aquatic Life Ambient Water Quality Criteria – Cadmium (EPA 820-R-16-002). Chronic cadmium exposure leads to adverse effects in the growth, reproductive, immune, and endocrine systems of aquatic organisms, which impacts their development and behavior.

 

The changes made to the human health criteria are based on the Environmental Protection Agency (EPA’s) latest scientific studies in the 2015 Human Health Water Quality Criteria. The revised standards for these organic constituents are intended to protect residents and visitors from exposure to these pollutants, particularly for those who eat fish or shellfish from District waters as a significant portion of their regular diet.

 

DOEE is also proposing changes to the E. coli recreational water quality criteria based on EPA’s 2012 Recreational Water Quality Criteria (EPA 820-F-12-058). The E. coli recreational criteria update establishes a new measurement of “statistical threshold value” and a new unit of measurement of “colony forming unit.” The previous E. coli criteria used a measurement of “single sample maximum” and a unit of “most probable number.” The duration for the geometric mean criteria will be updated from thirty (30) days to ninety (90) days.

 

Finally, the proposed rulemaking updates abbreviations and definitions. All other provisions, tables, and definitions in the Water Quality Standards chapter remain unchanged.

 

Before the final water quality standards are promulgated, DOEE will conduct an analysis of the environmental, technological, institutional, and socio-economic impacts of applying and enforcing the proposed standards as required by the Water Pollution Control Act, D.C. Official Code § 8-103.04. The public is invited to present information and comments regarding the scope and approach for conducting the required impact analysis of the above proposed regulations.

 

Chapter 11, WATER QUALITY STANDARDS, Title 21 DCMR, WATER AND SANITATION, is amended as follows:

 

Section 1104, STANDARDS, Subsection 1104.8, is amended to read as follows:

 

1104.8             Unless otherwise stated, the numeric criteria that shall be met to attain and maintain designated uses are as follows in Tables 1 through 3:

 

Table 1: Conventional Constituents Numeric Criteria

 

Constituenta

Class A

Class B

Class C

Chlorophyll ab,c (μg/L)(seasonal segment average)

 

July 1 through September 30

—

—

25

Dissolved Oxygen (mg/L)

Instantaneous minimum (year-round)d

—

—

5.0

 

February 1 through May 31b,c

 

 

7-day mean

—

—

6.0

 

 

Instantaneous minimum

—

—

5.0

 

June 1 through January 31b,c

 

 

30-day mean

—

—

5.5

 

 

7-day mean

—

—

4.0

 

 

Instantaneous minimume

—

—

3.2

E. colif (colony forming units (cfu)/100 mL)

 

90-day Geometric mean (GM)

126

—

—

 

Statistical Threshold Value (STV)

410

—

—

Hydrogen Sulfide (maximum μg/L)

—

—

2.0

Oil and Grease (mg/L)

—

—

10.0

pH

 

Greater than

6.0

6.0

6.0

 

And less than

8.5

8.5

8.5

Secchi Depthb,c (m)(seasonal segment average)

 

April 1 through October 31

—

—

0.8

Temperature (°C)

 

Maximum

—

—

32.2

 

Maximum change above ambient

—

—

2.8

Total Dissolved Gases (maximum % saturation)

—

—

110

Turbidity Increase above Ambient (NTU)

20

20

20

 

Notes:

a No more than ten percent (10%) criteria exceedances of the WQS may be allowed when interpreting data for conventional pollutants when assessing water quality standards attainment or impairment status for the purposes of reporting under CWA Section 305(b) and listing under CWA Section 303(d). Where the ten percent (10%) exceedance is not a specific criteria recommendation, the application of the ten percent exceedance assessment will be addressed in an assessment methodology.

 

The attainment of these WQS or impairment status will be determined in accordance with the following US EPA guidance documents: Guidelines for Preparation of the State Comprehensive Water Quality Assessments 305(b) Reports and Electronic Updates, EPA 841-B-97-002A and B (1997); Consolidated Assessment and Listing Methodology – Toward a Compendium of Best Practices (EPA 1st ed. 2002); and Guidance for 2006 Assessment, Listing and Reporting Requirements Pursuant to Sections 303(d), 305(b), and 314 of the Clean Water Act (Diane Regas, July 29, 2005). Future guidance documents will also be considered when they are issued.

 

b Attainment of the dissolved oxygen, water clarity and chlorophyll a water quality criteria that apply to tidal influenced Class C waters will be determined following the guidelines documented in the 2003 United States Environmental Protection Agency publication: Ambient Water Quality Criteria for Dissolved Oxygen, Water Clarity and Chlorophyll a for the Chesapeake Bay and its Tidal Tributaries, EPA 903-R-03-002 (April 2003, Region III Chesapeake Bay Program Office, Annapolis, Maryland); 2004 Addendum, EPA 903-R-04-005 (October 2004); 2007 Addendum, EPA 903-R-07-003 CBP/TRS 285/07 (July 2007); 2007 Chlorophyll Criterion Addendum, EPA 903-R-07-005 CBP/TRS 288-07 (November 2007); 2008 Addendum, EPA 903-R-08-001 CBP/TRS 290-08 (September 2008); and 2010 Criterion Addendum, EPA 903-R-10-002 CBP/TRS-301-10 (May 2010).

 

c Shall apply to tidally influenced waters only.

 

d This criterion applies to nontidal waters.

 

e At temperatures greater than in tidally influenced waters, an instantaneous minimum dissolved oxygen concentration of 4.3mg/L shall apply.

 

f The geometric mean (GM) and statistical threshold value (STV) criteria shall be used for assessing water quality trends, permitting, and all other Clean Water Act applications. The waterbody geometric mean shall not be greater than the ninety-day (90-day) geometric mean magnitude in any continuous ninety-day (90-day) interval. There shall not be greater than a ten  percent (10%) excursion frequency of the STV magnitude within the same ninety-day (90-day) interval. E. coli shall be measured using EPA-approved culturable Method 1603 or equivalent methods as recommended by the 2012 Recreational Water Quality Criteria, (EPA 820-F-12-058).

 

Table 2: Trace Metals and Inorganics Numeric Criteria

 

Constituenta

Trace metals and inorganics in μg/L, except where stated otherwise (see Notes below)

Class C

Class Db

CCC

4-Day Avg

CMC

1-Hour Avg

30-Day Avg

Ammonia, mg total ammonia nitrogen (TAN)/L

See Note g

See Note h

—

Antimony, dissolved

—

—

640

Arsenic, dissolved

150

340

0.14c

Cadmium, dissolved

See Notes d and e

See Notes d and e

—

Chlorine, total residual

11

19

—

Chromium, hexavalent, dissolved

11d

16d

—

Chromium, trivalent, dissolved

See Notes d and e

See Notes d and e

—

Copper, dissolved

See Notes d and e

See Notes d and e

—

Cyanide, free

5.2

22

400

Iron, dissolved

1,000

—

—

Lead, dissolved

See Notes d and e

See Notes d and e

—

Mercury, total recoverable

0.77d

1.4d

0.15d

Methylmercury (mg/kg, fish tissue residue)

—

—

0.3

Nickel, dissolved

See Notes d and e

See Notes d and e

4,600

Selenium, total recoverable

5

20

4,200

Silver, dissolved

—

See Notes d and e

65,000

Thallium, dissolved

—

—

0.47

Zinc, dissolved

See Notes d and e

See Notes d and e

26,000

 

Notes:

a For constituents with blank numeric criteria, EPA has not calculated standards at this time. However, permit authorities will address these constituents in National Pollutant Discharge Elimination System (NPDES) permit actions using the narrative criteria for toxics.

 

b The Class D Human Health Criteria for metals will be based on Total Recoverable metals.

 

c The criteria is based on carcinogenicity of 10−6 risk level.

 

d The formulas for calculating the criterion for the hardness dependent constituents indicated above are as follows:

 

Table 2a: Formulas for Hardness-Dependent Constituentsf

 

Constituent

CCC

μg/L

CMC

μg/L

Cadmium

e(0.7977[ln(hardness)] − 3.909)

e(0.9789[ln(hardness)] − 3.866)

Chromium III

e(0.8190[ln(hardness)] + 0.6848)

e(0.8190[ln(hardness)] + 3.7256)

Copper

e(0.8545[ln(hardness)] − 1.702)

e(0.9422[ln(hardness)] − 1.700)

Lead

e(1.2730[ln(hardness)] − 4.705)

e(1.2730[ln(hardness)] − 1.460)

Nickel

e(0.8460[ln(hardness)] + 0.0584)

e(0.8460[ln(hardness)] + 2.255)

Silver

—

e(1.7200[ln(hardness)] − 6.590)

Zinc

e(0.8473[ln(hardness)] + 0.884)

e(0.8473[ln(hardness)] + 0.884)

 

e The criterion derived from the formulas under Note d is multiplied by the conversion factor in Table 2b as specified in Subsection 1105.10:

 

 Table 2b: Conversion Factorsf

 

Constituent

CCC

CMC

Cadmium

1.101672 − [(ln hardness)(0.041838)]

1.136672 − [(ln hardness)(0.041838)]

Chromium III

0.860

0.316

Chromium VI

0.962

0.982

Copper

0.960

0.960

Lead

1.46203 − [(ln hardness)(0.145712)]

1.46203 − [(ln hardness)(0.145712)]

Mercury

0.85

0.85

Nickel

0.997

0.998

Silver

—

0.85

Zinc

0.986

0.978

 

f Hardness in Tables 2a and 2b shall be measured as mg/L of calcium carbonate (CaCO3).  The minimum hardness value allowed for use in these formulas shall not be less than 25 mg/L as CaCO3, even if the actual ambient hardness is less than twenty-five (25) mg/L as CaCO3. The maximum hardness value allowed for use in these formulas shall not exceed four hundred (400) mg/L as CaCO3, even if the actual ambient water hardness is greater than 400 mg/L as CaCO3.

 

g Criterion Continuous Concentration (CCC) for total ammonia nitrogen (in mg TAN/L):

 

(a)                The CCC for total ammonia nitrogen (in mg TAN/L) (i) shall be the thirty (30) day average concentration for total ammonia nitrogen computed for a design flow specified in Subsection 1105.5; and (ii) shall account for the influence of the pH and temperature as shown in Table 2c. The highest four (4) day average within the thirty (30) day period shall not exceed 2.5 times the CCC.

 

(b)        The CCC in Table 2c was calculated using the following formula, which shall be used to calculate unlisted values: CCC =


Table 2c: Total Ammonia Nitrogen (in milligrams of total ammonia nitrogen per liter (mg TAN/L)

CCC for Various pH and Temperatures

 

Temperature (°C)

pH

0-7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

29

30

6.5

4.9

4.6

4.3

4.1

3.8

3.6

3.3

3.1

2.9

2.8

2.6

2.4

2.3

2.1

2.0

1.9

1.8

1.6

1.5

1.5

1.4

1.3

1.2

1.1

6.6

4.8

4.5

4.3

4.0

3.8

3.5

3.3

3.1

2.9

2.7

2.5

2.4

2.2

2.1

2.0

1.8

1.7

1.6

1.5

1.4

1.3

1.3

1.2

1.1

6.7

4.8

4.5

4.2

3.9

3.7

3.5

3.2

3.0

2.8

2.7

2.5

2.3

2.2

2.1

1.9

1.8

1.7

1.6

1.5

1.4

1.3

1.2

1.2

1.1

6.8

4.6

4.4

4.1

3.8

3.6

3.4

3.2

3.0

2.8

2.6

2.4

2.3

2.1

2.0

1.9

1.8

1.7

1.6

1.5

1.4

1.3

1.2

1.1

1.1

6.9

4.5

4.2

4.0

3.7

3.5

3.3

3.1

2.9

2.7

2.5

2.4

2.2

2.1

2.0

1.8

1.7

1.6

1.5

1.4

1.3

1.2

1.2

1.1

1.0

7.0

4.4

4.1

3.8

3.6

3.4

3.2

3.0

2.8

2.6

2.4

2.3

2.2

2.0

1.9

1.8

1.7

1.6

1.5

1.4

1.3

1.2

1.1

1.1

0.99

7.1

4.2

3.9

3.7

3.5

3.2

3.0

2.8

2.7

2.5

2.3

2.2

2.1

1.9

1.8

1.7

1.6

1.5

1.4

1.3

1.2

1.2

1.1

1.0

0.95

7.2

4.0

3.7

3.5

3.3

3.1

2.9

2.7

2.5

2.4

2.2

2.1

2.0

1.8

1.7

1.6

1.5

1.4

1.3

1.3

1.2

1.1

1.0

0.96

0.90

7.3

3.8

3.5

3.3

3.1

2.9

2.7

2.6

2.4

2.2

2.1

2.0

1.8

1.7

1.6

1.5

1.4

1.3

1.3

1.2

1.1

1.0

0.97

0.91

0.85

7.4

3.5

3.3

3.1

2.9

2.7

2.5

2.4

2.2

2.1

2.0

1.8

1.7

1.6

1.5

1.4

1.3

1.3

1.2

1.1

1.0

0.96

0.90

0.85

0.79

7.5

3.2

3.0

2.8

2.7

2.5

2.3

2.2

2.1

1.9

1.8

1.7

1.6

1.5

1.4

1.3

1.2

1.2

1.1

1.0

0.95

0.89

0.83

0.78

0.73

7.6

2.9

2.8

2.6

2.4

2.3

2.1

2.0

1.9

1.8

1.6

1.5

1.4

1.4

1.3

1.2

1.1

1.1

0.98

0.92

0.86

0.81

0.76

0.71

0.67

7.7

2.6

2.4

2.3

2.2

2.0

1.9

1.8

1.7

1.6

1.5

1.4

1.3

1.2

1.1

1.1

1.0

0.94

0.88

0.83

0.78

0.73

0.68

0.64

0.60

7.8

2.3

2.2

2.1

1.9

1.8

1.7

1.6

1.5

1.4

1.3

1.2

1.2

1.1

1.0

0.95

0.89

0.84

0.79

0.74

0.69

0.65

0.61

0.57

0.53

7.9

2.1

1.9

1.8

1.7

1.6

1.5

1.4

1.3

1.2

1.2

1.1

1.0

0.95

0.89

0.84

0.79

0.74

0.69

0.65

0.61

0.57

0.53

0.50

0.47

8.0

1.8

1.7

1.6

1.5

1.4

1.3

1.2

1.1

1.1

1.0

0.94

0.88

0.83

0.78

0.73

0.68

0.64

0.60

0.56

0.53

0.50

0.44

0.44

0.41

8.1

1.5

1.5

1.4

1.3

1.2

1.1

1.1

0.99

0.92

0.87

0.81

0.76

0.71

0.67

0.63

0.59

0.55

0.52

0.49

0.46

0.43

0.40

0.38

0.35

8.2

1.3

1.2

1.2

1.1

1.0

0.96

0.90

0.84

0.79

0.74

0.70

0.65

0.61

0.57

0.54

0.50

0.47

0.44

0.42

0.39

0.37

0.34

0.32

0.30

8.3

1.1

1.1

0.99

0.93

0.87

0.82

0.76

0.72

0.67

0.63

0.59

0.55

0.52

0.49

0.46

0.43

0.40

0.38

0.35

0.33

0.31

0.29

0.27

0.26

8.4

0.95

0.89

0.84

0.79

0.74

0.69

0.65

0.61

0.57

0.53

0.50

0.47

0.44

0.41

0.39

0.36

0.34

0.32

0.30

0.28

0.26

0.25

0.23

0.22

8.5

0.80

0.75

0.71

0.67

0.62

0.58

0.55

0.51

0.48

0.45

0.42

0.40

0.37

0.35

0.33

0.31

0.29

0.27

0.25

0.24

0.22

0.21

0.20

0.18

8.6

0.68

0.64

0.60

0.56

0.53

0.49

0.46

0.43

0.41

0.38

0.36

0.33

0.31

0.29

0.28

0.26

0.24

0.23

0.21

0.20

0.19

0.18

0.16

0.15

8.7

0.57

0.54

0.51

0.47

0.44

0.42

0.39

0.37

0.34

0.32

0.30

0.28

0.27

0.25

0.23

0.22

0.21

0.19

0.18

0.17

0.16

0.15

0.14

0.13

8.8

0.49

0.46

0.43

0.40

0.38

0.35

0.33

0.31

0.29

0.27

0.26

0.24

0.23

0.21

0.20

0.19

0.17

0.16

0.15

0.14

0.13

0.13

0.12

0.11

8.9

0.42

0.39

0.37

0.34

0.32

0.30

0.28

0.27

0.25

0.23

0.22

0.21

0.19

0.18

0.17

0.16

0.15

0.14

0.13

0.12

0.12

0.11

0.10

0.09

9.0

0.36

0.34

0.32

0.30

0.28

0.26

0.24

0.23

0.21

0.20

0.19

0.18

0.17

0.16

0.15

0.14

0.13

0.12

0.11

0.11

0.10

0.09

0.09

0.08


h Criterion Maximum Concentration (CMC) for total ammonia nitrogen (in mg TAN/L): 

 

(a)        The CMC for total ammonia nitrogen (in mg TAN/L) (i) shall be the one (1) average concentration for total ammonia nitrogen, computed for a design flow specified in Subsection 1105.5; and (ii) shall account for the influence of the pH as shown in Table 2d.

 

(b)        The CMC was calculated using the following formula, which shall be used to calculate unlisted values: CMC =


Table 2d: Total Ammonia Nitrogen (in milligrams of total ammonia nitrogen per liter (mg TAN/L)

CMC for Various pH and Temperatures

 

Temperature (°C)

pH

0-10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

29

30

6.5

51

48

44

41

37

34

32

29

27

25

23

21

19

18

16

15

14

13

12

11

9.9

6.6

49

46

42

39

36

33

30

28

26

24

22

20

18

17

16

14

13

12

11

10

9.5

6.7

46

44

40

37

34

31

29

27

24

22

21

19

18

16

15

14

13

12

11

9.8

9.0

6.8

44

41

38

35

32

30

27

25

23

21

20

18

17

15

14

13

12

11

10

9.2

8.5

6.9

41

38

35

32

30

28

25

23

21

20

18

17

15

14

13

12

11

10

9.4

8.6

7.9

7.0

38

35

33

30

28

25

23

21

20

18

17

15

14

13

12

11

10

9.4

8.6

7.9

7.3

7.1

34

32

30

27

25

23

21

20

18

17

15

14

13

12

11

10

9.3

8.5

7.9

7.2

6.7

7.2

31

29

27

25

23

21

19

18

16

15

14

13

12

11

9.8

9.1

8.3

7.7

7.1

6.5

6.0

7.3

27

26

24

22

20

18

17

16

14

13

12

11

10

9.5

8.7

8.0

7.4

6.8

6.3

5.8

5.3

7.4

24

22

21

19

18

16

15

14

13

12

11

9.8

9.0

8.3

7.7

7.0

6.5

6.0

5.5

5.1

4.7

7.5

21

19

18

17

15

14

13

12

11

10

9.2

8.5

7.8

7.2

6.6

6.1

5.6

5.2

4.8

4.4

4.0

7.6

18

17

15

14

13

12

11

10

9.3

8.6

7.9

7.3

6.7

6.2

5.7

5.2

4.8

4.4

4.1

3.8

3.5

7.7

15

14

13

12

11

10

9.3

8.6

7.9

7.3

6.7

6.2

5.7

5.2

4.8

4.4

4.1

3.8

3.5

3.2

2.9

7.8

13

12

11

10

9.3

8.5

7.9

7.2

6.7

6.1

5.6

5.2

4.8

4.4

4.0

3.7

3.4

3.2

2.9

2.7

2.5

7.9

11

9.9

9.1

8.4

7.7

7.1

6.6

3.0

5.6

5.1

4.7

4.3

4.0

3.7

3.4

3.1

2.9

2.6

2.4

2.2

2.1

8.0

8.8

8.2

7.6

7.0

6.4

5.9

5.4

5.0

4.6

4.2

3.9

3.6

3.3

3.0

2.8

2.6

2.4

2.2

2.0

1.9

1.7

8.1

7.2

6.8

6.3

5.8

5.3

4.9

4.5

4.1

3.8

3.5

3.2

3.0

2.7

2.5

2.3

2.1

2.0

1.8

1.7

1.5

1.4

8.2

6.0

5.6

5.2

4.8

4.4

4.0

3.7

3.4

3.1

2.9

2.7

2.4

2.3

2.1

1.9

1.8

1.6

1.5

1.4

1.3

1.2

8.3

4.9

4.6

4.3

3.9

3.6

3.3

3.1

2.8

2.6

2.4

2.2

2.0

1.9

1.7

1.6

1.4

1.3

1.2

1.1

1.0

0.96

8.4

4.1

3.8

3.5

3.2

3.0

2.7

2.5

2.3

2.1

2.0

1.8

1.7

1.5

1.4

1.3

1.2

1.1

1.0

0.93

0.86

0.79

8.5

3.3

3.1

2.9

2.7

2.4

2.3

2.1

1.9

1.8

1.6

1.5

1.4

1.3

1.2

1.1

0.98

0.90

0.83

0.77

0.71

0.65

8.6

2.8

2.6

2.4

2.2

2.0

1.9

1.7

1.6

1.5

1.3

1.2

1.1

1.0

0.96

0.88

0.81

0.75

0.69

0.63

0.58

0.54

8.7

2.3

2.2

2.0

1.8

1.7

1.6

1.4

1.3

1.2

1.1

1.0

0.94

0.87

0.80

0.74

0.68

0.62

0.57

0.53

0.49

0.45

8.8

1.9

1.8

1.7

1.5

1.4

1.3

1.2

1.1

1.0

0.93

0.86

0.79

0.73

0.67

0.62

0.57

0.52

0.48

0.44

0.41

0.37

8.9

1.6

1.5

1.4

1.3

1.2

1.1

1.0

0.93

0.85

0.79

0.72

0.67

0.61

0.56

0.52

0.48

0.44

0.40

0.37

0.34

0.32

9.0

1.4

1.3

1.2

1.1

1.0

0.93

0.86

0.79

0.73

0.67

0.62

0.57

0.52

0.48

0.44

0.41

0.37

0.34

0.32

0.29

0.27


Table 3: Organic Constituents Numeric Criteria

 

Organic Constituenta

(μg/L)

CAS

Number

Chemical Family Group

Class C

Class C

Class D

CCC

4-Day Avg

CMC

1-Hour Avg

30-Day

Avg

 

Acenaphthene

83-32-9

Polynuclear aromatic hydrocarbon

50

—

90

Acrolein

107-02-8

Acryl aldehyde

3.0

3.0

400

Acrylonitrile

107-13-1

Nonionic organic

700.0

—

7.0b

Aldrin

309-00-2

Pesticide

0.4

3.0

0.00000077b

alpha-Endosulfan

959-98-8

Endosulfan

0.056

0.22

30 

alpha-Hexachlorocyclohexane (HCH)

319-84-6

Hexachlorocyclohexane

—

—

0.00039b

Anthracene

120-12-7

Polynuclear aromatic hydrocarbon

—

—

400

Benzene

71-43-2

Hydrocarbon

1,000

—

16b

Benzidine

92-87-5

Aromatic amine

250

—

0.011b

Benzo(a)anthracene

56-55-3

Polynuclear aromatic hydrocarbon

—

—

0.0013b

Benzo(a)pyrene

50-32-8

Polynuclear aromatic hydrocarbon

—

—

0.00013

Benzo(b)fluoranthene

205-99-2

Polynuclear aromatic hydrocarbon

—

—

0.0013

Benzo(k)fluoranthene                   

207-08-9

Polynuclear aromatic hydrocarbon

—

—

0.013

beta-Endosulfan

33213-65-9

Endosulfan

0.056

0.22

40

beta-Hexachlorocyclohexane (HCH)

319-85-7

Hexachlorocyclohexane

—

—

0.014b

Bis(2-Chloroethyl) Ether

111-44-4

Chloroalkyl ether

—

—

2.2

Bis(Chloromethyl) Ether

542-88-1

Chloroalkyl ether

—

—

0.017

Bis(2-Chloro-1-methylethyl) Ether

108-60-1

Chloroalkyl ether

—

—

4,000

Bis(2-Ethylhexyl) Phthalate

117-81-7

Phthalate ester

—

—

0.37b

Bromoform

75-25-2

Halomethane

—

—

120b

Butylbenzyl Phthalate

85-68-7

Phthalate ester

—

—

0.10

Carbaryl (Sevin)

63-25-2

Insecticide

2.1

2.1

—

Carbon Tetrachloride

56-23-5

Halomethane

1,000

—

5b

Chlordane

57-74-9

Insecticide

0.0043

2.4

0.00032b

Chlorobenzene

108-90-7

Chlorinated benzene

—

—

800

Chlorodibromomethane

124-48-1

Halomethane

—

—

21b

Chloroform

67-66-3

Halomethane

3,000

—

2,000b

2-Chloronaphthalene

91-58-7

Chlorinated naphthalene

200

—

1,000

2-Chlorophenol

95-57-8

Chlorinated phenol

100

—

800

Chlorophenoxy Herbicide (2,4-D)

94-75-7

Herbicide

—

—

12,000

Chlorophenoxy Herbicide (2,4,5-TP) [Silvex]

93-72-1

Herbicide

—

—

400

Chrysene

218-01-9

Polynuclear aromatic hydrocarbon

—

—

0.13b

Dibenzo(a,h)anthracene

53-70-3

Polynuclear aromatic hydrocarbon

—

—

0.00013b

1,2-Dichlorobenzene

95-50-1

Chlorinated benzene

200

—

3,000

1,3-Dichlorobenzene

541-73-1

Chlorinated benzene

200

—

10

1,4-Dichlorobenzene

106-46-7

Chlorinated benzene

200

—

900

3,3'-Dichlorobenzidine

91-94-1

Chlorinated aromatic amine

10

—

0.15b

Dichlorobromomethane

75-27-4

Halomethane

—

—

27b

1,2-Dichloroethane

107-06-2

Chlorinated ethane

—

—

650b

1,1-Dichloroethylene

75-35-4

Dichloroethylene

—

—

20,000b

2,4-Dichlorophenol

120-83-2

Chlorinated phenol

200

—

60

1,2-Dichloropropane

78-87-5

Volatile organic compound

2,000

—

31b

1,3-Dichloropropene

542-75-6

Chlorocarbon

—

—

12

Dieldrin

60-57-1

Organochloride insecticide

0.056

0.24

0.0000012b

Diethyl Phthalate

84-66-2

Phthalate ester

—

—

600

2,4-Dimethylphenol

105-67-9

Semivolatile organic compound

200

—

3,000

Dimethyl Phthalate

131-11-3

Phthalate ester

—

—

2,000

Di-n-Butyl Phthalate

84-74-2

Phthalate ester

—

—

30

2,4-Dinitrophenol

51-28-5

Dinitrophenol

—

—

300

Dinitrophenols

25550-58-7

Dinitrophenol

—

—

1,000

2,4-Dinitrotoluene

121-14-2

Amino compound

33

—

1.7

1,2-Diphenylhydrazine

122-66-7

Semivolatile organic compound

30

—

0.2b

Endosulfan Sulfate

1031-07-8

Chlorinated hydrocarbon insecticide

—

—

40

Endrin

72-20-8

Insecticide

0.036

0.086

0.03

Endrin Aldehyde

7421-93-4

Pesticide

—

—

1

Ethylbenzene

100-41-4

Aromatic hydrocarbon

40

—

130

Fluoranthene

206-44-0

Polynuclear aromatic hydrocarbon

400

—

20

Fluorene

86-73-7

Polynuclear aromatic hydrocarbon

—

—

70

gamma-BHC (Lindane)

58-89-9

Hexachlorocyclohexane

0.08

0.95

4.4b

Guthion

86-50-0

Organophosphate

0.01

—

—

Heptachlor

76-44-8

Organochlorine insecticide

0.0038

0.52

0.0000059b

Heptachlor Epoxide

1024-57-3

Organochlorine insecticide

0.0038

0.52

0.000032b

Hexachlorobenzene

118-74-1

Chlorinated benzene

—

—

0.000079b

Hexachlorobutadiene

87-68-3

Chlorinated aliphatic diene

10

—

0.01b

Hexachlorocyclohexane (HCH) -Technical

608-73-1

Insecticide

—

—

0.010

Hexachlorocyclopentadiene

77-47-4

Organochlorine

0.5

—

4

Hexachloroethane

67-72-1

Chlorinated ethane

—

—

0.1b

Indeno(1,2,3-cd)pyrene

193-39-5

Polynuclear aromatic hydrocarbon

—

—

0.0013b

Isophorone

78-59-1

Cyclic ketone

1,000

—

1,800b

Malathion

121-75-5

Organophosphate

0.1

—

—

Manganese

7439-96-5

Mineral element (metal)

—

—

100

Methoxychlor

72-43-5

Organochlorine insecticide

0.03

—

0.02

Methyl Bromide

74-83-9

Halomethane

—

—

10,000

3-Methyl-4-Chloro-phenol

59-50-7

Antimicrobial pesticide (disinfectant)

—

—

2,000

2-Methyl-4,6-Dinitrophenol

534-52-1

Dinitrophenol

—

—

30

Methylene Chloride

75-09-2

Halomethane

—

—

1,000b

Mirex

2385-85-5

Organochloride insecticide

0.001

—

—

Nitrobenzene

98-95-3

Organic compound

1,000

—

600

Nitrosamines

N/A

A nitroso group bonded to an amine

600

—

1.24

Nitrosodibutylamine, N

924-16-3

Nitrosamine

—

—

0.22

Nitrosodiethylamine, N

55-18-5

Nitrosamine

—

—

1.24

Nitrosopyrrolidine, N

930-55-2

Nitrosamine

—

—

34b

N-Nitrosodimethylamine

62-75-9

Nitrosamine

—

—

3.0b

N-Nitrosodi-n-Propylamine

621-64-7

Nitrosamine

—

—

0.51b

N-Nitrosodiphenylamine

86-30-6

Nitrosamine

—

—

6.0b

Nonylphenol

84852-15-3

Alkyl-phenols

6.6

28

—

Parathion

56-38-2

Organophosphate

0.013

0.065

—

Pentachlorobenzene

608-93-5

Chlorinated benzene

—

—

0.1

Pentachlorophenol

87-86-5

Chlorinated phenol

See Note c

See Note c

0.04b

Phenol

108-95-2

Phenol

—

—

300,000

Polychlorinated Biphenyls (PCBs)

N/A

Organochlorine

0.014d

—

0.000064d

p,p’-Dichlorodiphenyldichloroethane (DDD)

72-54-8

Organochloride

0.001

1.1

0.00012b

p,p’-Dichlorodiphenyldichloroethylene (DDE)

72-55-9

Organochloride

0.001

1.1

0.000018b

p,p’-Dichlorodiphenyltrichloroethane (DDT)

50-29-3

Organochloride

0.001

1.1

0.000030b

Pyrene

129-00-0

Polynuclear aromatic hydrocarbon

—

—

30

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

1746-01-6

Polychlorinated dibenzodioxins

—

—

0.0000000051b

1,2,4,5-Tetrachlorobenzene

95-94-3

Chlorinated benzene

—

—

0.03

1,1,2,2-Tetrachloroethane

79-34-5

Chlorinated ethane

—

—

3b

Tetrachloroethylene

127-18-4

Chlorinated hydrocarbons

800

—

29b

Toluene

108-88-3

Aromatic hydrocarbon

600

—

520

Toxaphene

8001-35-2

Organophosphate insecticide

0.0002

0.73

0.00071b

Trans-1,2-Dichloroethylene

156-60-5

Dichloroethylene

—

—

4,000

Tributyltin (TBT)

688-73-3

Organotin

0.072

0.46

—

1,2,4-Trichlorobenzene

120-82-1

Chlorinated benzene

—

—

0.076

1,1,1-Trichloroethane

71-55-6

Chlorinated ethane

—

—

200,000

1,1,2-Trichloroethane

79-00-5

Chlorinated ethane

—

—

8.9b

Trichloroethylene

79-01-6

Halocarbon

1,000

—

7b

2,4,5-Trichlorophenol

95-95-4

Chlorinated phenol

—

—

600

2,4,6-Trichlorophenol

88-06-2

Chlorinated phenol

—

—

2.8b

Vinyl Chloride

75-01-4

Organochloride

—

—

1.6b

 

Notes:

a For constituents with blank numeric criteria, EPA has not calculated standards at this time. However, permit authorities will address these constituents in NPDES permit actions using the narrative criteria for toxics.

 

b The criteria is based on carcinogenicity of 10−6 risk level.

 

c The formulas for calculating the concentrations of substances indicated above are as follows:

 

[I]        The numerical CCC for pentachlorophenol in μg/L shall be given by:

e(1.005(pH) - 5.134)

[I.A]    The numerical CMC for pentachlorophenol in μg/L shall be given by:

e(1.005(pH) - 4.869)

d The polychlorinated biphenyls (PCB) criterion applies to total PCBs (e.g., the sum of all congener, isomer, homolog, or Aroclor analyses.)

 

Section 1199, DEFINITIONS, is amended to read as follows:

 

1199                DEFINITIONS

 

1199.1             When used in this chapter, the following terms shall have the meanings ascribed:

 

Acute toxic – the concentration of a substance that is lethal to fifty percent (50%) of the test organisms within ninety-six (96) hours, also referred to as the LC50.

 

Ambient – those environmental conditions existing before or upstream of a source or incidence of pollution.

 

Anadromous fish – fish that spend most of their lives in saltwater but migrate into freshwater tributaries to spawn.

 

Aquatic life – all animal and plant life including, but not limited to, rooted underwater grasses found in District waters.

 

Background water quality – the levels of chemical, physical, biological, and radiological constituents or parameters in the water upgradient of a facility, practice, or activity and which have not been affected by that facility, practice, or activity.

 

Best management practices (BMPs) – schedules of activities, prohibitions of practices, maintenance procedures, and other management practices to prevent or reduce the discharge of pollutants to the waters of the District.  BMPs also include practices found to be the most effective and practical means of preventing or reducing point and nonpoint source pollution to levels that are compatible with water quality goals.

 

Contamination – an impairment of water quality by biological, chemical, physical, or radiological materials which lowers the water quality to a degree that creates a potential hazard to the environment or public health or interferes with a designated use.

 

Criteria – any of the group of physical, chemical, biological, and radiological water quality parameters and the associated numerical concentrations or levels that compose the numerical standards of the water quality standards and that define a component of the quality of the water needed for a designated use.

 

CCC or Criterion Continuous Concentration – the highest concentration of a pollutant to which aquatic life can be exposed for an extended period of time (four (4) day average) without deleterious effects at a frequency that does not exceed more than once every three (3) years.

 

CMC or Criterion Maximum Concentration – the highest concentration of a pollutant to which aquatic life can be exposed for a short period of time (one (1) hour  average) without deleterious effects at a frequency that does not exceed more than once every three (3) years.

 

Consumption of fish and shellfish – the human ingestion of fish and shellfish, which is not chemically contaminated at a level that will cause a significant adverse health impact, caught from the District’s waters.

 

Current use – the use that is generally and usually attained based upon the water quality in the waterbody.

 

Department – the Department of Energy and Environment, or any successor agency.

 

Designated use – the use specified for the waterbody in these water quality standards whether or not they are being attained.

 

Director – the Director of the Department, or his or her designee.

 

District waters – the waters of the District of Columbia.

 

e – base e exponential function.

 

Early warning value – a concentration that is a percentage of, or a practical quantitation limit for, a groundwater quality criterion or enforcement standard.

 

EPA – United States Environmental Protection Agency.

 

Enforcement standard – the value assigned to a contaminant for the purpose of regulating an activity, which may be the same as the criterion for that contaminant.

 

Existing use – the use actually attained in the waterbody on or after November 28, 1975.

 

Federal Clean Water Act – the Federal Water Pollution Control Act Amendments of 1972, approved October 18, 1972 (86 Stat. 816; 33 U.S.C. §§ 1251 et seq.), as amended.

 

Geometric mean (GM) – the nth root of the product of n numbers.

 

Groundwater – underground water, excluding water in pipes, tanks, and other containers created or set up by people.

 

Harmonic mean flow – the number of daily flow measurements divided by the sum of the reciprocals of the flows. It is the reciprocal of the mean of the reciprocals.

 

High quality waters – waters of a quality that is better than needed to protect fishable and swimmable streams.

 

Landfill – a disposal facility or part of a facility at which solid waste is permanently placed in or on land and which is not a land spreading facility.

 

Land spreading disposal facility – a facility that applies sludge or other solid wastes onto the land or incorporates solid waste in the soil surface at greater than vegetative utilization and soil conditioners/immobilization rates.

 

LC50 or lethal concentration – the numerical limit or concentration of a test material mixed in water that is lethal to fifty percent (50%) of the aquatic organisms exposed to the test material for a period of ninety-six (96) hours.

 

Load or loading – an amount of matter or thermal energy that is introduced into a receiving water; to introduce matter or thermal energy into a receiving water. Loading may be either man-caused (pollutant loading) or natural (natural background loading).

 

Mixing zone – a limited area or a volume of water where initial dilution of a discharge takes place and where numerical water quality criteria may be exceeded but acute toxic conditions are prevented from occurring. 

 

Narrative criteria – a condition that should not be attained in a specific medium to maintain a given designated use and that is generally expressed in a “free from” format.

 

Navigation – the designated use for certain District waters. This designation applies to waters that are subject to the ebb and flow of the tides, or waters that are presently used, may have been used, or may be used for shipping, travel, and transportation of interstate or foreign commerce by vessel.

 

Nonpoint source – any source from which pollutants are or may be discharged other than a point source.

 

Nontidal waters – waters in the streams not subject to regular and periodic tidal action.

 

Numerical criteria – the maximum level of a contaminant, the minimum level of a constituent, or the acceptable range of a parameter in water to maintain a given designated use.

 

Permit or permitted – a written authorization issued or certified by the Director under pertinent laws and regulations for an activity, facility, or entity to discharge, treat, store, or dispose of materials or wastes.

 

Point of compliance – the point or points that must not exceeded to comply with a water quality enforcement standard or criterion.

 

Point source – any discrete source of quantifiable pollutants, including a municipal treatment facility discharge, residential, commercial or industrial waste discharge, a combined sewer overflow; or any discernible, confined, and discrete conveyance, including any pipe, ditch, channel, tunnel, conduit, well, discrete fissure, container, rolling stock, or concentrated animal feeding operation from which contaminants are or may be discharged.

 

Pollution – the man-made or man-induced alteration of the chemical, physical, biological, or radiological integrity of water.

 

Pollutant – any substance that may alter or interfere with the restoration or maintenance of the chemical, physical, radiological, or biological integrity of the waters of the District, including dredged soil, solid waste, incinerator residue, sewage, garbage, sewage sludge, munitions, chemical wastes, hazardous wastes, biological materials, radioactive materials, heat, wrecked or discarded equipment, rock, sand, cellar dirt, oil, gasoline and related petroleum products, and industrial, municipal, and agricultural wastes.

 

Practical quantitation limit – the lowest concentration of a substance that generally can be determined by qualified laboratories within specified limits of precision and accuracy under routine laboratory operating conditions in the matrix of concern.

 

Primary contact recreation – those water contact sports or activities that result in frequent whole body immersion or involve significant risks of ingestion of the water (Class A).

 

Responsible party – any person who has caused or is causing pollution or has created or is creating a condition from which pollution is likely to occur.

 

Secondary contact recreation – those water contact sports or activities that seldom result in whole body immersion or do not involve significant risks of ingestion of the water (Class B).

 

Semi-anadromous fish – fish that spend most of their lives in tidally influenced low to medium salinity waters but migrate to freshwater tributaries to spawn.

 

Short-term degradation – the period during which the waterbody may be degraded based on the nature of the pollutant and the degree of its environmental or human health impact, as determined by the Director on a case-by-case basis.

 

Solid waste – all putrescible and non‑putrescible solid and semisolid wastes, including garbage, rubbish, ashes, industrial wastes, swill, demolition and construction wastes, abandoned vehicles or parts thereof, and discarded commodities. This term also includes all liquid, solid, and semisolid materials that are not the primary products of public, private, industrial or commercial mining, and agricultural operations.

 

Standards – those regulations, in the form of numerical, narrative, or enforcement standards, that specify a level of quality of the waters of the District necessary to sustain the designated uses.

 

Statistical threshold value (STV) – the statistical threshold value is based on the water quality distribution observed during EPA’s epidemiological studies. STV approximates the ninetieth (90th) percentile of the water quality distribution and is intended to be a value that should not be exceeded by more than 10 percent of the samples used to calculate the geometric mean.

 

Surface impoundment – a facility or part of a facility that is a natural topographic depression, man-made excavation, or diked area formed primarily of earthen materials (although it may be lined with man-made materials), and that is designed to hold an accumulation of liquids or sludge.

 

Surface waters – all rivers, lakes, ponds, wetlands, inland waters, streams, and other water and water courses within the jurisdiction of the District of Columbia.

 

Tidally influenced waters – surface waters within the Potomac River, the Anacostia River, and all embayments and tributaries to these rivers that are under the influence of tidal exchange.

 

Toxic substance – any substance or combination of substances that after discharge and upon exposure, ingestion, inhalation, or assimilation into any organism, either directly from the environment or indirectly by ingestion through food chains, may cause death, disease, behavioral abnormalities, cancer, genetic mutations, physiological malfunctions (including malfunctions in reproduction), or physical deformities in the organism or its offspring.

 

Trend analysis – a statistical methodology used to detect net changes or trends in contaminant levels over time.

 

Water Effect Ratio or (WER) – the ratio of the site water LC50 value to the laboratory water LC50 value.

 

Waters of the District or District waters – flowing and still bodies of water, whether artificial or natural, whether underground or on land, so long as in the District of Columbia, but excluding water on private property prevented from reaching underground or land watercourses, and also excluding water in closed collection or distribution systems.

 

Wetland – a marsh, swamp, bog, or other area periodically inundated by tides or having saturated soil conditions for prolonged periods of time and capable of supporting aquatic vegetation.

 

Wildlife – all animal life whether indigenous or migratory regardless of life stage including, but not limited to, birds, anadromous and semi-anadromous fish, shellfish, and mammals including sensitive species that are found in or use the District waters.

 

1199.2             When used in this chapter, the following abbreviations shall have the meaning ascribed:

 

BMPs              best management practices

ºC                    degrees centigrade or Celsius

CaCO3                 calcium carbonate

CCC                criterion continuous concentration

CMC               criterion maximum concentration

cfu                   colony forming units

CF                   conversion factor

DOEE             Department of Energy and Environment

e                      base e exponential function

E. coli              Escherichia coli

EPA                United States Environmental Protection Agency

GM                  geometric mean

IRIS                EPA’s Integrated Risk Information System database

L                      liter

LC50                lethal concentration

ln                     natural logarithm

m                     meter

mg/L                milligrams per liter

mg TAN/L      milligrams of total ammonia nitrogen per liter

mL                   milliliter

μg/L                 microgram per liter

NPDES           National Pollutant Discharge Elimination System

NTU                Nephelometric turbidity units

PCBs               polychlorinated biphenyls

pH                   hydrogen ion concentration

q1*                  carcinogenic potency slope factor

STV                 statistical threshold value

SWDC            Special Waters of the District of Columbia

TAN                total ammonia nitrogen

WER               Water-Effect Ratio

WQS               water quality standards

 

 

The proposed regulations are available for viewing at https://doee.dc.gov/service/water-quality-regulations. To pick up a copy of these proposed regulations at 1200 First Street N.E., 5th Floor, Washington, D.C. 20002, call Rebecca Diehl at (202) 535-2648 and mention this Notice by name. All persons desiring to comment on the proposed regulations should file comments in writing not later than sixty (60) days after the publication of this notice in the D.C. Register.

 

Comments on the proposed rule and the scope and approach to the required Water Quality Criteria Impact Analysis should identify the commenter and be clearly marked “DOEE Water Quality Standards, Proposed Rule Comments.” Comments may be (1) mailed or hand-delivered to DOEE, Water Quality Division, 1200 First Street NE, 5th Floor, Washington, D.C. 20002, Attention: DOEE Water Quality Standards, or (2) sent by e-mail to WQS@dc.gov, with the subject indicated as “DOEE Water Quality Standards Proposed Rule Comments.”