Washington Administrative Code
Title 173 - Ecology, Department of (See also Titles 197, 317, 372, and 508)
Chapter 173-200 - Water quality standards for groundwaters of the state of Washington
Section 173-200-040 - Criteria

Universal Citation: WA Admin Code 173-200-040

Current through Register Vol. 24-06, March 15, 2024

(1) Groundwaters in the state of Washington support many different beneficial uses. The purpose of these criteria is to establish maximum contaminant concentrations for the protection of a variety of beneficial uses of Washington's groundwater.

(a) Drinking water is the beneficial use generally requiring the highest quality of groundwater.

(b) Providing protection to the level of drinking water standards will protect a great variety of existing and future beneficial uses.

(c) Some groundwaters of the state support environmental systems with existing and future beneficial uses requiring more stringent protection than that provided by human health based criteria. These groundwaters and dependent uses will be protected by either or both of the following:
(i) Designation of an area and its associated groundwater as a special protection area in accordance with WAC 173-200-090.

(ii) Establishment of enforcement limits as close to the natural groundwater quality as possible for activities that may adversely affect those groundwaters in accordance with WAC 173-200-050.

(d) The use of criteria based on drinking water quality shall in no way be interpreted to mean that all groundwaters are used for drinking water or that all groundwaters are presently suitable for drinking water.

(2) The following criteria shall apply to all groundwaters in the state of Washington:

(a) Groundwater concentrations shall not exceed the criteria listed in Table 1, except as described in WAC 173-200-050(3)(b).

(b) For the primary and secondary contaminants and radionuclides listed in Table 1, the criteria shall be the most stringent concentration of the following and those listed in Table 1:
(i) Maximum contaminant level goals;

(ii) Maximum contaminant levels; and

(iii) State maximum contaminant levels published in chapter 248-54 WAC as presently promulgated or subsequently amended or repromulgated.

The criteria for primary and secondary contaminants and radionuclide contaminants in Table 1 shall be amended as the federal and state rules are amended and without amendment of this chapter.

(c) For carcinogens listed in Table 1, the criteria are the concentrations that are anticipated to result in a total incremental human cancer risk of less than 1 in 1,000,000, and were estimated using the following equation and standard exposure assumptions:

Groundwater Criteria =

(ug/1)

RISK x BW x LIFE x UCF

CPF x DWIR x DUR

Where:

RISK

=

Human cancer risk level (1 in 1,000,000)

BW

=

Body Weight (70 kg)

LIFE

=

Lifetime (70 years)

UCF

=

Unit conversion factor (1,000 ug/mg)

CPF

=

Cancer potency factor as published in the IRIS

data base (1/mg/kg/day)

DWIR

=

Drinking water ingestion rate (2.0 liters/day)

DUR

=

Duration of exposure (30 years)

For volatile carcinogens, inhalation exposure from showering was incorporated into the criteria by doubling the drinking water ingestion rate.

(3) For contaminants for which no numeric criteria have been established, enforcement limits shall be established in accordance with WAC 173-200-050.

TABLE 1

GROUNDWATER QUALITY CRITERIA

CONTAMINANT

CRITERION

I.

PRIMARY AND SECONDARY CONTAMINANTS AND

RADIONUCLIDES

A.

PRIMARY CONTAMINANTS

Barium*

1.0

milligrams/

liter (mg/1)

Cadmium*

0.01

mg/1

Chromium*

0.05

mg/1

Lead*

0.05

mg/1

Mercury*

0.002

mg/1

Selenium*

0.01

mg/1

Silver*

0.05

mg/1

Fluoride

4

mg/1

Nitrate (as N)

10

mg/1

Endrin

0.0002

mg/1

Methoxychlor

0.1

mg/1

1,1,1-Trichloroethane

0.20

mg/1

2-4 D

0.10

mg/1

2,4,5-TP Silvex

0.01

mg/1

Total Coliform Bacteria

1/100

ml

B.

SECONDARY CONTAMINANTS

Copper*

1.0

mg/1

Iron*

0.30

mg/1

Manganese*

0.05

mg/1

Zinc*

5.0

mg/1

Chloride

250

mg/1

Sulfate

250

mg/1

Total Dissolved Solids

500

mg/1

Foaming Agents

0.5

mg/1

pH

6.5-8.5

Corrosivity

noncorrosive

Color

15 color units

Odor

3 threshold

odor units

C.

RADIONUCLIDES

Gross Alpha Particle Activity

15

pico Curie/

liter (pCi/1)

Gross Beta Particle Radioactivity

Gross Beta Activity

Tritium

Strontium-90

50

20,000

8

pCi/l

pCi/l

pCi/l

Radium 226 & 228

5

pCi/1

Radium -226

3

pCi/1

II. CARCINOGENS

Acrylamide

0.02

micrograms/

liter ug/1

Acrylonitrile

0.07

ug/1

Aldrin

0.005

ug/1

Aniline

14

ug/1

Aramite

3

ug/1

Arsenic*

0.05

(ug/1)

Azobenzene

0.7

ug/1

Benzene

1.0

ug/1

Benzidine

0.0004

ug/1

Benzo(a)pyrene

0.008

ug/1

Benzotrichloride

0.007

ug/1

Benzyl chloride

0.5

ug/1

Bis(chloroethyl)ether

0.07

ug/1

Bis(chloromethyl)ether

0.0004

ug/1

Bis(2-ethylhexyl) phthalate

6.0

ug/1

Bromodichloromethane

0.3

ug/1

Bromoform

5

ug/1

Carbazole

5

ug/1

Carbon tetrachloride

0.3

ug/1

Chlordane

0.06

ug/1

Chlorodibromomethane

0.5

ug/1

Chloroform

7.0

ug/1

4 Chloro-2-methyl aniline

0.1

ug/1

4 Chloro-2-methyl analine

hydrochloride

0.2

ug/1

o-Chloronitrobenzene

3

ug/1

p-Chloronitrobenzene

5

ug/1

Chlorthalonil

30

ug/1

Diallate

1

ug/1

DDT (includes DDE and DDD)

0.3

ug/1

1,2 Dibromoethane

0.001

ug/1

1,4 Dichlorobenzene

4

ug/1

3,3' Dichlorobenzidine

0.2

ug/1

1,1 Dichloroethane

1.0

ug/1

1,2 Dichloroethane

(ethylene chloride)

0.5

ug/1

1,2 Dichloropropane

0.6

ug/1

1,3 Dichloropropene

0.2

ug/1

Dichlorvos

0.3

ug/1

Dieldrin

0.005

ug/1

3,3' Dimethoxybenzidine

6

ug/1

3,3 Dimethylbenzidine

0.007

1,2 Dimethylhydrazine

60

ug/1

2,4 Dinitrotoluene

0.1

ug/1

2,6 Dinitrotoluene

0.1

ug/1

1,4 Dioxane

7.0

ug/1

1,2 Diphenylhydrazine

0.09

ug/1

Direct Black 38

0.009

ug/1

Direct Blue 6

0.009

ug/1

Direct Brown 95

0.009

ug/1

Epichlorohydrin

8

ug/1

Ethyl acrylate

2

ug/1

Ethylene dibromide

0.001

ug/1

Ethylene thiourea

2

ug/1

Folpet

20

ug/1

Furazolidone

0.02

ug/1

Furium

0.002

ug/1

Furmecyclox

3

ug/1

Heptachlor

0.02

ug/1

Heptachlor Epoxide

0.009

ug/1

Hexachlorobenzene

0.05

ug/1

Hexachlorocyclohexane (alpha)

0.001

ug/1

Hexachlorocyclohexane

(technical)

0.05

ug/1

Hexachlorodibenzo-p-dioxin, mix

0.00001

ug/1

Hydrazine/Hydrazine sulfate

0.03

ug/1

Lindane

0.06

ug/1

2 Methoxy-5-nitroaniline

2

ug/1

2 Methylaniline

0.2

ug/1

2 Methylaniline hydrochloride

0.5

ug/1

4,4' Methylene bis(N,N'-dimethyl)

aniline

2

ug/1

Methylene chloride

(dichloromethane)

5

ug/1

Mirex

0.05

ug/1

Nitrofurazone

0.06

ug/1

N-Nitrosodiethanolamine

0.03

ug/1

N-Nitrosodiethylamine

0.0005

ug/1

N-Nitrosodimethylamine

0.002

ug/1

N-Nitrosodiphenylamine

17

ug/1

N-Nitroso-di-n-propylamine

0.01

ug/1

N-Nitrosopyrrolidine

0.04

ug/1

N-Nitroso-di-n-butylamine

0.02

ug/1

N-Nitroso-N-methylethylamine

0.004

ug/1

PAH

0.01

ug/1

PBBs

0.01

ug/1

PCBs

0.01

ug/1

o-Phenylenediamine

0.005

ug/1

Propylene oxide

0.01

ug/1

2,3,7,8-Tetrachlorodibenzo-

p-dioxin

0.0000006

ug/1

Tetrachloroethylene

(perchloroethylene)

0.8

ug/1

p,ALPHA,ALPHA,ALPHA-Tetrachlorotoluene

0.004

ug/1

2,4 Toluenediamine

0.002

ug/1

o-Toluidine

0.2

ug/1

Toxaphene

0.08

ug/1

Trichloroethylene

3

ug/1

2,4,6-Trichlorophenol

4

ug/1

Trimethyl phosphate

2

ug/1

Vinyl chloride

0.02

ug/1

*metals are measured as total metals

Statutory Authority: RCW 90.48.035. 90-22-023, § 173-200-040, filed 10/31/90, effective 12/1/90.

Disclaimer: These regulations may not be the most recent version. Washington 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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