S afe D rinking W ater A ct

Safe

Drinking

Water

Act Marty Swickarddrinking water programEPA Region 8

25 years old in 1999

SDWA -- Pre-History (b.s.)• Late 1800’s (just over 100 years ago) Modern

microbiology started. We figured out that living things are made of cells, that bacteria exist, and that some of them can make us sick …

• 1914 US Public Health Service (PHS)developed first national standards (for bacteriological quality); they applied to water moving in interstate commerce (trains)

SDWA -- Pre-History (continued)• 1930’s Classical waterborne diseases

(e.g.typhoid fever, amoebic dysentery, bacillary dysentery, cholera) are mostly controlled in the US through increased use of disinfectants, etc.

• 1940’s The “chemical revolution” begins

• 1946 PHS standards also applied to planes and buses; they now included some chemical standards

SDWA -- Pre-History (continued)• 1962 --Last revisions to drinking water

standards made by PHS.--Emphasis was still on infectious disease though some chemicals were included

--About 20 standards - some mandatory, some recommended--Also recommended use of qualifiedpersonnel, use of water from protected sources, control of pollution of sources, chlorination of water from sources notadequately protected

SDWA -- History• 1970 A study of community systems showed

widespread problems with water qualityand health risks associated with deficiencies in facilities, O&M, etc.

• 1971 The first viruses are detected in treateddrinking water (2 systems in Massachusetts)

• 1974 The first asbestos is discovered in drinking water (Duluth, MN)

SDWA -- History• 1974 EPA announced finding small

amounts of 66 organic chemicals,some carcinogenic, in New Orleansdrinking water

• Dec. 1974 Congress enacted the SDWA

• 1975 EPA confirmed that trihalomethanesare formed when chlorine is added to water containing certain organics

• 1986 & 1996 Congress passed major amendments to the SDWA

SDWA -- Major Provisions -- 1974• The federal government (EPA) is to set

standards for drinking water• States are to assure compliance with and

enforce the standards• Water systems are responsible for the quality

of water they serve (they are the regulated entities)

• Underground sources of drinking water are to be protected from contamination from injection wells (UIC program)

SDWA -- Major Provisions -- 1986

• Required EPA to regulate 83 contaminants by 1989 (only about 22 had been regulated so far)

• Required EPA to regulate 25 new contaminants every 3 years

• Required EPA to set requirements for filtration and disinfection of water supplies

• Banned the use of lead pipes and solder• Established the voluntary wellhead protection

program

SDWA -- Major Provisions -- 1996

• Eliminated the “25 new contaminants every 3 years” requirement

• Required EPA to conduct cost-benefit analysis in setting standards

• Expanded consumer information requirements

• Increased protection of source water

• Strengthened enforcement, including against Federal facilities

SDWA -- EPA’s Rule-making Under the Act

• As required by the SDWA, EPA has promulgated regulations

– to assure water systems serve safe water

– to control underground injection wells

• The UIC rules can be found in the Code of Federal Regulations at 40 CFR Parts 144 - 149 (more about these later in the training)

SDWA -- EPA’s Rule-making (cont.)

• Regulations on water systems can be found in the Code of Federal Regulations at 40 CFR Parts 141, 142, and 143


• Part 141 is the National Primary Drinking Water Regulations (NPDWRs) that water systems must comply with.– These protect human health,– Are enforceable– Contain the MCLs and requirements for

monitoring and treatment, etc.


• Part 142 covers how the States, Tribes, and EPA implement the Public Water System Supervision (PWSS) program.

– Provides for delegation to states or tribes with oversight by EPA

– Provides rules for federally-issued variances or exemptions

– Provides for federal enforcement

SDWA -- EPA’s Rule-making (cont.)• Part 143 is the National Secondary

Drinking Water Regulations (NSDWRs)

– It contains Secondary MCLs (SMCLs)

– These are recommended standards that relate to the acceptability of drinking water to consumers

– These are not enforceable (except for the public notice required for exceedance of the fluoride SMCL)

SDWA / NPDWRs -- Basic Concepts

SDWA / NPDWRs -- Basic Concepts (cont.)

• Public Water System (PWS) -- a system for the provision to the public of water for human consumption through pipes or other constructed conveyances,

if such system has at least fifteen service connections or regularly serves an average of at least twenty-five individuals

daily at least 60 days out of the year (SDWA Sec. 1401(4), 40 CFR 141.2)


• Community Water System (CWS) -- a public water system that serves at least 15 service connections used by year-round residents or regularly serves at least 25 year-round residents.

• Serves people where they live.• Exposure to contaminants could be lifetime.

(SDWA Sec. 1401(15), 40 CFR 141.2)


• Noncommunity Water System (NCWS) -- a public water system that is not a community water system.

• There are two types of non-community systems (based on the length of exposure of the consumers to the water): transient and non-transient.

(SDWA Sec. 1401(16), 40 CFR 141.2)


• Non-transient Noncommunity Water System (NTNCWS) -- a public water system that is not a community water system but that regularly serves at least 25 of the same persons over 6 months of the year.

• e.g., schools or businesses with their own water system

• Exposure to contaminants could be similar to that for community water systems.

(40 CFR 141.2)


• Transient Noncommunity Water System (TNCWS) -- a noncommunity water system that does not regularly serve at least 25 of the same individuals at least 6 months per year.

• e.g., rest areas, campgrounds, truck stops, visitor centers with their own water system

• Individual exposure to the water is very short-term. (40 CFR 141.2)


• MCLG and MCL (& TT)– Maximum Contaminant Level Goal

(MCLG) -- maximum level of a contaminant at which no known or anticipated adverse health effects occur with an adequate margin of safety

(SDWA Sec. 1412(b)(4)(A); 40 CFR 141.2)

• These are non-enforceable goals based on health effects only.


– Maximum Contaminant Level Goal -- (MCLG) (continued)

• The MCLG for carcinogens is “0” (we don’t know of a threshold below which there is no effect).

• Must be published for each contaminant for which an MCL or treatment technique is set.


– Maximum Contaminant Level (MCL) --maximum permissible level of a contaminant which is delivered to any user of a public water system.

(SDWA Sec. 1401(3) & 1412(b)(4)(B)&(D); 40 CFR 141.2)

• Enforceable standard.


– Maximum Contaminant Level (MCL) (cont.)• Set as close to the MCLG as is “feasible”.

• Feasible means feasible with the use of the best technology, treatment techniques and other means which EPA finds, after examination for efficacy under field conditions and not solely under laboratory conditions, are available, taking costs into consideration.


– Treatment Technique Requirement (TT) -- If the level of a contaminant in drinking water is too hard or too expensive to test for, EPA may set a treatment technique requirement in lieu of an MCL• e.g., the Surface Water Treatment Rule

(SWTR)


– Treatment Technique Requirement (cont.)• Enforceable requirement

• Must be treatment techniques which, in EPA’s judgment, would prevent known or anticipated adverse effects on the health of persons to the extent feasible.

(SDWA Sec. 1401(1)(C)(ii) & 1412(b)(7))

Documents

S afe D rinking W ater A ct