12VAC5-590-340. Compliance standards.
A. All physical, chemical, bacteriological, or radiological analyses for the purpose of demonstrating compliance with the requirements of this chapter shall be performed by laboratories that have received certification by EPA or DCLS as specified in 12VAC5-590-440. The owner is responsible for the collection and submission of all samples. The department may require sampling and testing that exceeds the minimal requirements specified in this chapter. A sample is deemed to have been collected only when its results are made known to the department.
B. Specific limits. No attempt has been made to prescribe specific limits for every contaminant that might occur in a water supply or a waterworks. Although the need exists for continued attention to the entry of chemical, physical, bacteriological, and radiological substances into drinking water, the limits are confined to substances recognized as being detrimental to the health or well-being of the consumer or that cause significant degradation of the usefulness of the water. Limits for innumerable substances would require an impossible burden of analytical examination. The specific limits included in this chapter are listed in Tables 340.1 through 340.7.
C. Compliance is determined:
1. Based on sample results or calculated averages, where appropriate, rounded to the same number of significant figures as the PMCL, SMCL, AL, or MRDL of the contaminant in question, or
2. By the application of the specific treatment technique for particular contaminants (see 12VAC5-590-391).
TABLE 340.1 Inorganic Chemicals | |
SUBSTANCE | PMCL (mg/L) |
Antimony | 0.006 |
Arsenic | 0.010a |
Asbestos | 7 million fibers/liter (longer than 10 µm) |
Barium | 2 |
Beryllium | 0.004 |
Cadmium | 0.005 |
Chromium | 0.1 |
Cyanide (as free Cyanide) | 0.2 |
Fluoride | 4.0b |
Mercury | 0.002 |
Nickel | No limits designated |
Nitrate (as N) | 10c |
Nitrite (as N) | 1.0c |
Total Nitrate and Nitrite (as N) | 10c |
Selenium | 0.05 |
Thallium | 0.002 |
SUBSTANCE | SECONDARY MAXIMUM CONTAMINANT LEVEL (mg/L) |
Aluminum | 0.05-0.2d |
Chloride | 250c |
Copper | 1.0 |
Corrosivity | Noncorrosive |
Fluoride | 2.0 |
Foaming agents | 0.5e |
Iron | 0.3 |
Manganese | 0.05 |
Silver | 0.1 |
Sodium | No limits designatedf |
Sulfate | 250c |
Zinc | 5 |
SUBSTANCE | ACTION LEVEL (mg/L) |
Lead | 0.015 |
Copper | 1.3 |
aArsenic sampling results shall be reported to the nearest 0.001 mg/L. bThe fluoride PMCL applies only to community waterworks. cSignificant figures are noted as shown. For values with trailing zeros, significant figures are noted as shown. The limits for nitrate and nitrate-nitrite have two significant figures. The limits for chloride and sulfate have three significant figures. dVarying water quality and treatment situations necessitates a flexible range for the aluminum SMCL. The owner is encouraged to maintain an aluminum concentration as low as possible. If the aluminum concentration in the finished water causes discoloration, then the owner is urged to contact the department. eConcentrations reported in terms of Methylene Blue Active Substances. fMonitoring and reporting in accordance with 40 CFR 141. 41 and 12VAC5-590-372 D 6. |
TABLE 340.2 Organic Chemicals | |
SUBSTANCE | PMCL (mg/L) |
VOC | |
Benzene | 0.005 |
Carbon tetrachloride | 0.005 |
Chlorobenzene (also called Monochlorobenzene) | 0.1 |
o-Dichlorobenzene | 0.6 |
p-Dichlorobenzene | 0.075 |
1,2-Dichloroethane (also called Ethylene dichloride) | 0.005 |
1,1-Dichloroethylene (also called Dichloroethene) | 0.007 |
cis-1,2-Dichloroethylene | 0.07 |
Trans-1,2-Dichloroethylene | 0.1 |
Dichloromethane (also called Methylene chloride) | 0.005 |
1,2-Dichloropropane | 0.005 |
Ethylbenzene | 0.7 |
Styrene | 0.1 |
Tetrachloroethylene (PCE) (also called Perchloroethylene) | 0.005 |
Toluene | 1 |
1,2,4-Trichlorobenzene | 0.07 |
1,1,1-Trichloroethane | 0.2 |
1,1,2-Trichloroethane | 0.005 |
Trichloroethylene (TCE) | 0.005 |
Vinyl Chloride | 0.002 |
Xylene (total) | 10a |
SOC | |
Acrylamide | TTb |
Alachlor (also called Lasso) | 0.002 |
Atrazine | 0.003 |
Benzo(a)pyrene | 0.0002 |
Carbofuran | 0.04 |
Chlordane | 0.002 |
Dalapon | 0.2 |
Di(2-ethylhexyl)adipate (also called Bis(2-ethylhexyl)adipate) | 0.4 |
Di(2-ethylhexyl)phthalate (also called Bis(2-ethylhexyl)phthalate) | 0.006 |
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 |
Epichlorohydrin | TTb |
Ethylene dibromide (EDB) (also called 1,2-Dibromoethane) | 0.00005 |
Glyphosate | 0.7 |
Heptachlor | 0.0004 |
Heptachlor epoxide | 0.0002 |
Hexachlorobenzene | 0.001 |
Hexachlorocyclopentadiene | 0.05 |
Lindane (also called gamma-HCH and gamma BHC) | 0.0002 |
Methoxychlor | 0.04 |
Oxamyl (Vydate) | 0.2 |
Pentachlorophenol (PCP) | 0.001 |
Picloram | 0.5 |
Polychlorinated biphenyls (PCBs) | 0.0005 |
Simazine | 0.004 |
2,3,7,8-TCDD (Dioxin) | 3 X 10-8 |
Toxaphene | 0.003 |
2,4,5-Trichlorophenoxypropionic Acid (2,4,5-TP or Silvex) | 0.05 |
aThe limit for xylene has two significant figures. bEach waterworks must certify annually to the department that when acrylamide and epichlorohydrin are used to treat water, the combination (or product) of dose and monomer level does not exceed the levels specified as follows: (i) acrylamide = 0.05% dosed at 1 mg/L (or equivalent) and (ii) epichlorohydrin = 0.01% dosed at 20 mg/L (or equivalent). The certification shall be in writing, using third-party certification approved by the department or the manufacturer's certification. |
TABLE 340.3 Physical Quality | ||
PARAMETER | STANDARD | CONCENTRATION |
Color | SMCL | 15 Color Units (CU) |
Odor | SMCL | 3 Threshold odor numbers |
pH | SMCL | 6.5-8.5 |
Total dissolved solids (TDS) | SMCL | 500 mg/La |
Turbidity | Treatment Technique | See 12VAC5-590-395 A 2 bb |
aTDS has three significant figures. bOperational goal: Surface water treatment plants with gravity flow granular media filters are capable of producing filtered water with a turbidity consistently less than 0.10 NTU. Therefore, for water treatment plants, the operational goal for filter effluent turbidity for each filter, before any post-filtration chemical addition, is 0.10 NTU. |
TABLE 340.4 Radiological Quality | ||
PARAMETER | PMCL | |
Combined radium-226 and radium-228. | 5 pCi/L | |
Gross alpha particle activity (excluding Radon and Uranium) | 15 pCi/L | |
Beta particle and photon radioactivity. | 4 mrem/yr a, b | |
Uranium | 30 µg/Lc | |
aThe average annual concentration of beta particle and photon radioactivity from man-made radionuclides in drinking water shall not produce an annual dose equivalent to the total body or any internal organ greater than 4 mrem/year. bExcept for the radionuclides listed in Schedule I, the concentration of man-made radionuclides causing 4 mrem 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 Concentrations of Radionuclides in Air and in Water for Occupational Exposure," NBS Handbook 69 issued June 5, 1959, and amended August 1963, U.S. Department of Commerce. 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 mrem/year. cThe limit for uranium has two significant figures. | ||
Schedule 1 | ||
Average annual concentrations assumed to produce a total body organ dose of 4 mrem/year. | ||
RADIONUCLIDE | CRITICAL ORGAN | pCi/L |
Tritium | Total Body | 20,000d |
Strontium-90 | Bone Marrow | 8 |
dThe limit for tritium has five significant figures. |
TABLE 340.5 Microbial Contaminants | |
CONTAMINANT | PMCL or TT |
Cryptosporidium | TT Minimum 99% (2-log) removal plus additional log removal or inactivation based upon bin classification in 12VAC5-590-401 D. |
Giardia lamblia | TT 99.9% (3-log) removal or inactivation. |
Viruses | TT 99.99% (4-log) removal or inactivation |
Legionella | TT No limit, but if Giardia lamblia and viruses are removed or inactivated, according to the treatment techniques in 12VAC5-590-395, Legionella will also be controlled. |
Heterotrophic plate count (HPC) | TT No more than 500 bacterial colonies per milliliter. (HPC is not a contaminant, it is an analytic method used to measure a variety of bacteria found in water.) |
Escherichia coli (E. coli) | PMCL (1) Any E. coli-positive repeat sample following a total coliform-positive routine sample. (2) Total coliform-positive repeat sample following an E. coli-positive routine sample. (3) Failure to collect all require repeat samples following an E. coli-positive routine sample. (4) Failure to test for E. coli when any repeat sample tests positive for total coliform. |
TABLE 340.6 Disinfection Byproducts | |
PARAMETER | PMCL (mg/L) |
TTHM Bromodichloromethane Bromoform Chloroform Dibromochloromethane | 0.080a |
HAA5 Bromoacetic acid Dibromoacetic acid Dichloroacetic acid Monochloroacetic acid Trichloroacetic acid | 0.060a |
Bromate | 0.010a |
Chlorite | 1.0a |
aThe limits for TTHM, HAA5, and bromate have three significant figures. The limit for chlorite has two significant figures. |
TABLE 340.7 Maximum Residual Disinfectant Level Goals (MRDLG) and Maximum Residual Disinfectant Levels (MRDL) for Disinfectants | |
RESIDUAL DISINFECTANT | MRDLG and MRDL (mg/L) |
Chlorine | 4.0 (as Cl2)a |
Chloramines | 4.0 (as Cl2)a |
Chlorine Dioxide | 0.8 (as ClO2) |
aChlorine and chloramines have two significant figures. |
D. Notwithstanding the MRDLs in Table 340.7, an owner may increase the residual disinfectant level of chlorine or chloramines (but not chlorine dioxide) in the distribution system to a level and for a time necessary to protect public health. This may include specific microbiological contamination problems caused by circumstances such as distribution line breaks, storm runoff events, water supply contamination events, or cross-connection events.
Statutory Authority
§§ 32.1-12 and 32.1-170 of the Code of Virginia.
Historical Notes
Derived from VR355-18-004.01 § 2.1, eff. August 1, 1991; amended, Virginia Register Volume 9, Issue 17, eff. June 23, 1993; Volume 12, Issue 2, eff. November 15, 1995; Volume 28, Issue 5, eff. December 7, 2011; Volume 37, Issue 20, eff. June 23, 2021; Errata, 37:22 VA.R. 3447 June 21, 2021.