N.H. Code Admin. R. Env-Wq 1703.26

Current through Register No. 25, June 20, 2024
Section Env-Wq 1703.26 - Freshwater Chronic Aquatic Life Criteria For Ammonia
(a) Subject to (b) through (d), below, Table 1703-4C shall be used to determine freshwater chronic aquatic life criteria for ammonia, in mg N/l.
(b) The freshwater chronic water quality criteria for ammonia in Table 1703-4C have been calculated by adding the value found by dividing 0.0278 by the sum of one plus 10 raised to the power of 7.688 minus the pH to the value found by dividing 1.1994 by one plus 10 raised to the power of pH minus 7.688, and multiplying the resulting value by 0.8876 multiplied by the value resulting from multiplying 2.126 by 10 raised to the power of 0.028 times the value of 20 minus the greater of the temperature or 7, as shown in the following equation:

Freshwater Chronic Criteria for Ammonia:

Criteria = 0.8876 x [0.0278/(1+10 7.688-pH) + 1.1994/(1+10 pH-7.688)] x [2.126 x 10 0.028 x (20-MAX(T,7))]

Where MAX indicates the greater of the two values separated by a comma.

(c) The chronic criteria in Table 1703-4C represent a 30-day rolling average, but the highest 4-day average within any 30-day averaging period shall not exceed 2.5 times the chronic criteria.
(d) The equation described in (b), above, shall be used to calculate criteria at unlisted pH and temperature values.
(e) Table 1703-4C shall be as follows:

Table 1703-4C: Freshwater Chronic Aquatic Life Criteria For Ammonia in mg N/l

pH

Temperature, Degrees C

0-7

8

10

12

14

16

18

20

22

24

26

28

30

6.5

4.9

4.6

4.1

3.6

3.1

2.8

2.4

2.1

1.9

1.6

1.5

1.3

1.1

6.6

4.8

4.5

4.0

3.5

3.1

2.7

2.4

2.1

1.8

1.6

1.4

1.3

1.1

6.7

4.8

4.5

3.9

3.5

3.0

2.7

2.3

2.1

1.8

1.6

1.4

1.2

1.1

6.8

4.6

4.4

3.8

3.4

3.0

2.6

2.3

2.0

1.8

1.6

1.4

1.2

1.1

6.9

4.5

4.2

3.7

3.3

2.9

2.5

2.2

2.0

1.7

1.5

1.3

1.2

1.0

7.0

4.4

4.1

3.6

3.2

2.8

2.4

2.2

1.9

1.7

1.5

1.3

1.1

0.99

7.1

4.2

3.9

3.5

3.0

2.7

2.3

2.1

1.8

1.6

1.4

1.2

1.1

0.95

7.2

4.0

3.7

3.3

2.9

2.5

2.2

2.0

1.7

1.5

1.3

1.2

1.0

0.90

7.3

3.8

3.5

3.1

2.7

2.4

2.1

1.8

1.6

1.4

1.3

1.1

0.97

0.85

7.4

3.5

3.3

2.9

2.5

2.2

2.0

1.7

1.5

1.3

1.2

1.0

0.90

0.79

7.5

3.2

3.0

2.7

2.3

2.1

1.8

1.6

1.4

1.2

1.1

0.95

0.83

0.73

7.6

2.9

2.8

2.4

2.1

1.9

1.6

1.4

1.3

1.1

0.98

0.86

0.76

0.67

7.7

2.6

2.4

2.2

1.9

1.7

1.5

1.3

1.1

1.0

0.88

0.78

0.68

0.60

7.8

2.3

2.2

1.9

1.7

1.5

1.3

1.2

1.0

0.89

0.79

0.69

0.61

0.53

7.9

2.1

1.9

1.7

1.5

1.3

1.2

1.0

0.89

0.79

0.69

0.61

0.53

0.47

8.0

1.8

1.7

1.5

1.3

1.1

1.0

0.88

0.78

0.68

0.60

0.53

0.44

0.41

8.1

1.5

1.5

1.3

1.1

0.99

0.87

0.76

0.67

0.59

0.52

0.46

0.40

0.35

8.2

1.3

1.2

1.1

0.96

0.84

0.74

0.65

0.57

0.50

0.44

0.39

0.34

0.30

8.3

1.1

1.1

0.93

0.82

0.72

0.63

0.55

0.49

0.43

0.38

0.33

0.29

0.26

8.4

0.95

0.89

0.79

0.69

0.61

0.53

0.47

0.41

0.36

0.32

0.28

0.25

0.22

8.5

0.80

0.75

0.67

0.58

0.51

0.45

0.40

0.35

0.31

0.27

0.24

0.21

0.18

8.6

0.68

0.64

0.56

0.49

0.43

0.38

0.33

0.29

0.26

0.23

0.20

0.18

0.15

8.7

0.57

0.54

0.47

0.42

0.37

0.32

0.28

0.25

0.22

0.19

0.17

0.15

0.13

8.8

0.49

0.46

0.40

0.35

0.31

0.27

0.24

0.21

0.19

0.16

0.14

0.13

0.11

8.9

0.42

0.39

0.34

0.30

0.27

0.23

0.21

0.18

0.16

0.14

0.12

0.11

0.09

9.0

0.36

0.34

0.30

0.26

0.23

0.20

0.18

0.16

0.14

0.12

0.11

0.09

0.08

N.H. Code Admin. R. Env-Wq 1703.26

(See Revision Note #1 at chapter heading for Env-Wq 1700) #7151, eff 12-10-99; ss by #9034, INTERIM, eff 12-10-07; ss by #9162, eff 5-21-08 (See Revision Note #2 at chapter heading for Env-Wq 1700)

Amended by Volume XXXVI Number 49, Filed December 8, 2016, Proposed by #12042, Effective 12/1/2016, Expires 12/1/2026.