Ariz. Admin. Code § 18-11-406

Current through Register Vol. 30, No. 49, December 6, 2024
Section R18-11-406 - Numeric Aquifer Water Quality Standards: Drinking Water Protected Use
A. The aquifer water quality standards in this Section apply to aquifers that are classified for drinking water protected use.
B. The following are the aquifer water quality standards for inorganic chemicals:

Pollutant

mg/L)

Antimony

0.006

Arsenic

0.05

Asbestos

7 million fibers/liter (longer than 10 mm)

Barium

2

Beryllium

0.004

Cadmium

0.005

Chromium

0.1

Cyanide (As Free Cyanide)

0.2

Fluoride

4.0

Lead

0.05

Mercury

0.002

Nickel

0.1

Nitrate (as N)

10

Nitrite (as N)

1

Nitrate and nitrite (as N)

10

Selenium

0.05

Thallium

0.002

C. The following are the aquifer water quality standards for organic chemicals:

Pollutant

(mg/L)

Benzene

0.005

Benzo (a) pyrene

0.0002

Carbon Tetrachloride

0.005

o-Dichlorobenzene

0.6

para-Dichlorobenzene

0.075

1,2-Dichloroethane

0.005

1,1-Dichloroethylene

0.007

cis-1,2-Dichloroethylene

0.07

trans-1,2-Dichloroethylene

0.1

1,2-Dichloropropane

0.005

Dichloromethane

0.005

Di (2-ethylhexyl) adipate

0.4

Di (2-ethylhexyl) pthalate

0.006

Ethylbenzene

0.7

Hexachlorobenzene

0.001

Hexachlorocyclopentadiene

0.05

Monochlorobenzene

0.1

Pentachlorophenol

0.001

Styrene

0.1

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

0.00000003

Tetrachloroethylene

0.005

Toluene

1

Trihalomethanes (Total)

0.10

1,2,4-Trichlorobenzene

0.07

1,1,1-Trichloroethane

0.20

1,1,2-Trichloroethane

0.005

Trichloroethylene

0.005

Vinyl Chloride

0.002

Xylenes (Total)

10

D. The following are the aquifer water quality standards for pesticides and polychlorinated biphenyls (PCBs):

Pollutant

(mg/L)

Alachlor

0.002

Atrazine

0.003

Carbofuran

0.04

Chlordane

0.002

Dalapon

0.2

1,2-Dibromo-3-Chloropropane (DBCP)

0.0002

2,4,-Dichlorophenoxyacetic Acid(2,4-D)

0.07

Dinoseb

0.007

Diquat

0.02

Endothall

0.1

Endrin

0.002

Ethylene Dibromide (EDB)

0.00005

Glyphosate

0.7

Heptachlor

0.0004

Heptachlor Epoxide

0.0002

Lindane

0.0002

Methoxychlor

0.04

Oxamyl

0.2

Picloram

0.5

Polychlorinated Biphenols (PCBs)

0.0005

Simazine

0.004

Toxaphene

0.003

2,4,5-Trichlorophenoxypropionic Acid (2,4,5-TP or Silvex)

0.05

E. The following are the aquifer water quality standards for radionuclides:
1. The maximum concentration for gross alpha particle activity, including Radium-226 but excluding radon and uranium, shall not exceed 15 pCi/l.
2. The maximum concentration for combined Radium-226 and Radium-228 shall not exceed 5 pCi/l.
3. The average annual concentration of beta particle and photon radioactivity from man-made radionuclides shall not produce an annual dose equivalent to the total body or any internal organ greater than 4 millirem/year.
4. Except for the radionuclides listed in this subsection, the concentration of man-made radionuclides causing 4 millirem total body or organ dose equivalents shall be calculated on the basis of a 2-liter-per-day drinking water intake using the 168-hour data listed in "Maximum Permissible Body Burdens and Maximum Permissible Concentration of Radionuclides in Air or Water for Occupational Exposure," National Bureau of Standards Handbook 69, National Bureau of Commerce, as amended August 1963 (and no future editions), incorporated herein by reference and on file with the Office of the Secretary of State and with the Department. If two or more radionuclides are present, the sum of their annual dose equivalent to the total body or to any organ shall not exceed 4 millirem/year. The following average annual concentrations are assumed to produce a total body or organ dose of 4 millirem/year:

Radionuclide

Critical Organ

pCi/l

Tritium

Total body

20,000

Strontium-90

Bone Marrow

8

F. The aquifer water quality standard for microbiological contaminants is based upon the presence or absence of total coliforms in a 100-milliliter sample. If a sample is total coliform-positive, a 100-milliliter repeat sample shall be taken within two weeks of the time the sample results are reported. Any total coliform-positive repeat sample following a total coliform-positive sample constitutes a violation of the aquifer water quality standard for microbiological contaminants.
G. The following are the aquifer water quality standards for turbidity:
1. One nephelometric turbidity unit as determined by a monthly average except that five or fewer nephelometric turbidity units may be allowed if it can be determined that the higher turbidity does not interfere with disinfection, prevent maintenance of effective disinfectant agents in water supply distribution systems, or interfere with microbiological determinations.
2. Five nephelometric turbidity units based on an average of two consecutive days.

Ariz. Admin. Code § R18-11-406

Adopted effective January 4, 1990 (Supp. 90-1). Amended effective August 14, 1992 (Supp. 92-3). Amended effective May 26, 1994 (Supp. 94-2).