
From the U.S. Code Online via GPO Access
[wais.access.gpo.gov]
[Laws in effect as of January 23, 2000]
[Document affected by Public Law 106-377 Section 1(a)(1)]
[CITE: 42USC300g-1]

 
                 TITLE 42--THE PUBLIC HEALTH AND WELFARE
 
                    CHAPTER 6A--PUBLIC HEALTH SERVICE
 
             SUBCHAPTER XII--SAFETY OF PUBLIC WATER SYSTEMS
 
                      Part B--Public Water Systems
 
Sec. 300g-1. National drinking water regulations


(a) National primary drinking water regulations; maximum contaminant 
        level goals; simultaneous publication of regulations and goals

    (1) Effective on June 19, 1986, each national interim or revised 
primary drinking water regulation promulgated under this section before 
June 19, 1986, shall be deemed to be a national primary drinking water 
regulation under subsection (b) of this section. No such regulation 
shall be required to comply with the standards set forth in subsection 
(b)(4) of this section unless such regulation is amended to establish a 
different maximum contaminant level after June 19, 1986.
    (2) After June 19, 1986, each recommended maximum contaminant level 
published before June 19, 1986, shall be treated as a maximum 
contaminant level goal.
    (3) Whenever a national primary drinking water regulation is 
proposed under subsection (b) of this section for any contaminant, the 
maximum contaminant level goal for such contaminant shall be proposed 
simultaneously. Whenever a national primary drinking water regulation is 
promulgated under subsection (b) of this section for any contaminant, 
the maximum contaminant level goal for such contaminant shall be 
published simultaneously.
    (4) Paragraph (3) shall not apply to any recommended maximum 
contaminant level published before June 19, 1986.

(b) Standards

    (1) Identification of contaminants for listing.--
        (A) General authority.--The Administrator shall, in accordance 
    with the procedures established by this subsection, publish a 
    maximum contaminant level goal and promulgate a national primary 
    drinking water regulation for a contaminant (other than a 
    contaminant referred to in paragraph (2) for which a national 
    primary drinking water regulation has been promulgated as of August 
    6, 1996) if the Administrator determines that--
            (i) the contaminant may have an adverse effect on the health 
        of persons;
            (ii) the contaminant is known to occur or there is a 
        substantial likelihood that the contaminant will occur in public 
        water systems with a frequency and at levels of public health 
        concern; and
            (iii) in the sole judgment of the Administrator, regulation 
        of such contaminant presents a meaningful opportunity for health 
        risk reduction for persons served by public water systems.

        (B) Regulation of unregulated contaminants.--
            (i) Listing of contaminants for consideration.--(I) Not 
        later than 18 months after August 6, 1996, and every 5 years 
        thereafter, the Administrator, after consultation with the 
        scientific community, including the Science Advisory Board, 
        after notice and opportunity for public comment, and after 
        considering the occurrence data base established under section 
        300j-4(g) of this title, shall publish a list of contaminants 
        which, at the time of publication, are not subject to any 
        proposed or promulgated national primary drinking water 
        regulation, which are known or anticipated to occur in public 
        water systems, and which may require regulation under this 
        subchapter.
            (II) The unregulated contaminants considered under subclause 
        (I) shall include, but not be limited to, substances referred to 
        in section 9601(14) of this title, and substances registered as 
        pesticides under the Federal Insecticide, Fungicide, and 
        Rodenticide Act [7 U.S.C. 136 et seq.].
            (III) The Administrator's decision whether or not to select 
        an unregulated contaminant for a list under this clause shall 
        not be subject to judicial review.
            (ii) Determination to regulate.--(I) Not later than 5 years 
        after August 6, 1996, and every 5 years thereafter, the 
        Administrator shall, after notice of the preliminary 
        determination and opportunity for public comment, for not fewer 
        than 5 contaminants included on the list published under clause 
        (i), make determinations of whether or not to regulate such 
        contaminants.
            (II) A determination to regulate a contaminant shall be 
        based on findings that the criteria of clauses (i), (ii), and 
        (iii) of subparagraph (A) are satisfied. Such findings shall be 
        based on the best available public health information, including 
        the occurrence data base established under section 300j-4(g) of 
        this title.
            (III) The Administrator may make a determination to regulate 
        a contaminant that does not appear on a list under clause (i) if 
        the determination to regulate is made pursuant to subclause 
        (II).
            (IV) A determination under this clause not to regulate a 
        contaminant shall be considered final agency action and subject 
        to judicial review.
            (iii) Review.--Each document setting forth the determination 
        for a contaminant under clause (ii) shall be available for 
        public comment at such time as the determination is published.

        (C) Priorities.--In selecting unregulated contaminants for 
    consideration under subparagraph (B), the Administrator shall select 
    contaminants that present the greatest public health concern. The 
    Administrator, in making such selection, shall take into 
    consideration, among other factors of public health concern, the 
    effect of such contaminants upon subgroups that comprise a 
    meaningful portion of the general population (such as infants, 
    children, pregnant women, the elderly, individuals with a history of 
    serious illness, or other subpopulations) that are identifiable as 
    being at greater risk of adverse health effects due to exposure to 
    contaminants in drinking water than the general population.
        (D) Urgent threats to public health.--The Administrator may 
    promulgate an interim national primary drinking water regulation for 
    a contaminant without making a determination for the contaminant 
    under paragraph (4)(C), or completing the analysis under paragraph 
    (3)(C), to address an urgent threat to public health as determined 
    by the Administrator after consultation with and written response to 
    any comments provided by the Secretary of Health and Human Services, 
    acting through the director of the Centers for Disease Control and 
    Prevention or the director of the National Institutes of Health. A 
    determination for any contaminant in accordance with paragraph 
    (4)(C) subject to an interim regulation under this subparagraph 
    shall be issued, and a completed analysis meeting the requirements 
    of paragraph (3)(C) shall be published, not later than 3 years after 
    the date on which the regulation is promulgated and the regulation 
    shall be repromulgated, or revised if appropriate, not later than 5 
    years after that date.
        (E) Regulation.--For each contaminant that the Administrator 
    determines to regulate under subparagraph (B), the Administrator 
    shall publish maximum contaminant level goals and promulgate, by 
    rule, national primary drinking water regulations under this 
    subsection. The Administrator shall propose the maximum contaminant 
    level goal and national primary drinking water regulation for a 
    contaminant not later than 24 months after the determination to 
    regulate under subparagraph (B), and may publish such proposed 
    regulation concurrent with the determination to regulate. The 
    Administrator shall publish a maximum contaminant level goal and 
    promulgate a national primary drinking water regulation within 18 
    months after the proposal thereof. The Administrator, by notice in 
    the Federal Register, may extend the deadline for such promulgation 
    for up to 9 months.
        (F) Health advisories and other actions.--The Administrator may 
    publish health advisories (which are not regulations) or take other 
    appropriate actions for contaminants not subject to any national 
    primary drinking water regulation.

    (2) Schedules and deadlines.--
        (A) In general.--In the case of the contaminants listed in the 
    Advance Notice of Proposed Rulemaking published in volume 47, 
    Federal Register, page 9352, and in volume 48, Federal Register, 
    page 45502, the Administrator shall publish maximum contaminant 
    level goals and promulgate national primary drinking water 
    regulations--
            (i) not later than 1 year after June 19, 1986, for not fewer 
        than 9 of the listed contaminants;
            (ii) not later than 2 years after June 19, 1986, for not 
        fewer than 40 of the listed contaminants; and
            (iii) not later than 3 years after June 19, 1986, for the 
        remainder of the listed contaminants.

        (B) Substitution of contaminants.--If the Administrator 
    identifies a drinking water contaminant the regulation of which, in 
    the judgment of the Administrator, is more likely to be protective 
    of public health (taking into account the schedule for regulation 
    under subparagraph (A)) than a contaminant referred to in 
    subparagraph (A), the Administrator may publish a maximum 
    contaminant level goal and promulgate a national primary drinking 
    water regulation for the identified contaminant in lieu of 
    regulating the contaminant referred to in subparagraph (A). 
    Substitutions may be made for not more than 7 contaminants referred 
    to in subparagraph (A). Regulation of a contaminant identified under 
    this subparagraph shall be in accordance with the schedule 
    applicable to the contaminant for which the substitution is made.
        (C) Disinfectants and disinfection byproducts.--The 
    Administrator shall promulgate an Interim Enhanced Surface Water 
    Treatment Rule, a Final Enhanced Surface Water Treatment Rule, a 
    Stage I Disinfectants and Disinfection Byproducts Rule, and a Stage 
    II Disinfectants and Disinfection Byproducts Rule in accordance with 
    the schedule published in volume 59, Federal Register, page 6361 
    (February 10, 1994), in table III.13 of the proposed Information 
    Collection Rule. If a delay occurs with respect to the promulgation 
    of any rule in the schedule referred to in this subparagraph, all 
    subsequent rules shall be completed as expeditiously as practicable 
    but no later than a revised date that reflects the interval or 
    intervals for the rules in the schedule.

    (3) Risk assessment, management, and communication.--
        (A) Use of science in decisionmaking.--In carrying out this 
    section, and, to the degree that an Agency action is based on 
    science, the Administrator shall use--
            (i) the best available, peer-reviewed science and supporting 
        studies conducted in accordance with sound and objective 
        scientific practices; and
            (ii) data collected by accepted methods or best available 
        methods (if the reliability of the method and the nature of the 
        decision justifies use of the data).

        (B) Public information.--In carrying out this section, the 
    Administrator shall ensure that the presentation of information on 
    public health effects is comprehensive, informative, and 
    understandable. The Administrator shall, in a document made 
    available to the public in support of a regulation promulgated under 
    this section, specify, to the extent practicable--
            (i) each population addressed by any estimate of public 
        health effects;
            (ii) the expected risk or central estimate of risk for the 
        specific populations;
            (iii) each appropriate upper-bound or lower-bound estimate 
        of risk;
            (iv) each significant uncertainty identified in the process 
        of the assessment of public health effects and studies that 
        would assist in resolving the uncertainty; and
            (v) peer-reviewed studies known to the Administrator that 
        support, are directly relevant to, or fail to support any 
        estimate of public health effects and the methodology used to 
        reconcile inconsistencies in the scientific data.

        (C) Health risk reduction and cost analysis.--
            (i) Maximum contaminant levels.--When proposing any national 
        primary drinking water regulation that includes a maximum 
        contaminant level, the Administrator shall, with respect to a 
        maximum contaminant level that is being considered in accordance 
        with paragraph (4) and each alternative maximum contaminant 
        level that is being considered pursuant to paragraph (5) or 
        (6)(A), publish, seek public comment on, and use for the 
        purposes of paragraphs (4), (5), and (6) an analysis of each of 
        the following:
                (I) Quantifiable and nonquantifiable health risk 
            reduction benefits for which there is a factual basis in the 
            rulemaking record to conclude that such benefits are likely 
            to occur as the result of treatment to comply with each 
            level.
                (II) Quantifiable and nonquantifiable health risk 
            reduction benefits for which there is a factual basis in the 
            rulemaking record to conclude that such benefits are likely 
            to occur from reductions in co-occurring contaminants that 
            may be attributed solely to compliance with the maximum 
            contaminant level, excluding benefits resulting from 
            compliance with other proposed or promulgated regulations.
                (III) Quantifiable and nonquantifiable costs for which 
            there is a factual basis in the rulemaking record to 
            conclude that such costs are likely to occur solely as a 
            result of compliance with the maximum contaminant level, 
            including monitoring, treatment, and other costs and 
            excluding costs resulting from compliance with other 
            proposed or promulgated regulations.
                (IV) The incremental costs and benefits associated with 
            each alternative maximum contaminant level considered.
                (V) The effects of the contaminant on the general 
            population and on groups within the general population such 
            as infants, children, pregnant women, the elderly, 
            individuals with a history of serious illness, or other 
            subpopulations that are identified as likely to be at 
            greater risk of adverse health effects due to exposure to 
            contaminants in drinking water than the general population.
                (VI) Any increased health risk that may occur as the 
            result of compliance, including risks associated with co-
            occurring contaminants.
                (VII) Other relevant factors, including the quality and 
            extent of the information, the uncertainties in the analysis 
            supporting subclauses (I) through (VI), and factors with 
            respect to the degree and nature of the risk.

            (ii) Treatment techniques.--When proposing a national 
        primary drinking water regulation that includes a treatment 
        technique in accordance with paragraph (7)(A), the Administrator 
        shall publish and seek public comment on an analysis of the 
        health risk reduction benefits and costs likely to be 
        experienced as the result of compliance with the treatment 
        technique and alternative treatment techniques that are being 
        considered, taking into account, as appropriate, the factors 
        described in clause (i).
            (iii) Approaches to measure and value benefits.--The 
        Administrator may identify valid approaches for the measurement 
        and valuation of benefits under this subparagraph, including 
        approaches to identify consumer willingness to pay for 
        reductions in health risks from drinking water contaminants.
            (iv) Authorization.--There are authorized to be appropriated 
        to the Administrator, acting through the Office of Ground Water 
        and Drinking Water, to conduct studies, assessments, and 
        analyses in support of regulations or the development of 
        methods, $35,000,000 for each of fiscal years 1996 through 2003.

    (4) Goals and standards.--
        (A) Maximum contaminant level goals.--Each maximum contaminant 
    level goal established under this subsection shall be set at the 
    level at which no known or anticipated adverse effects on the health 
    of persons occur and which allows an adequate margin of safety.
        (B) Maximum contaminant levels.--Except as provided in 
    paragraphs (5) and (6), each national primary drinking water 
    regulation for a contaminant for which a maximum contaminant level 
    goal is established under this subsection shall specify a maximum 
    contaminant level for such contaminant which is as close to the 
    maximum contaminant level goal as is feasible.
        (C) Determination.--At the time the Administrator proposes a 
    national primary drinking water regulation under this paragraph, the 
    Administrator shall publish a determination as to whether the 
    benefits of the maximum contaminant level justify, or do not 
    justify, the costs based on the analysis conducted under paragraph 
    (3)(C).
        (D) Definition of feasible.--For the purposes of this 
    subsection, the term ``feasible'' means feasible with the use of the 
    best technology, treatment techniques and other means which the 
    Administrator finds, after examination for efficacy under field 
    conditions and not solely under laboratory conditions, are available 
    (taking cost into consideration). For the purpose of this paragraph, 
    granular activated carbon is feasible for the control of synthetic 
    organic chemicals, and any technology, treatment technique, or other 
    means found to be the best available for the control of synthetic 
    organic chemicals must be at least as effective in controlling 
    synthetic organic chemicals as granular activated carbon.
        (E) Feasible technologies.--
            (i) In general.--Each national primary drinking water 
        regulation which establishes a maximum contaminant level shall 
        list the technology, treatment techniques, and other means which 
        the Administrator finds to be feasible for purposes of meeting 
        such maximum contaminant level, but a regulation under this 
        subsection shall not require that any specified technology, 
        treatment technique, or other means be used for purposes of 
        meeting such maximum contaminant level.
            (ii) List of technologies for small systems.--The 
        Administrator shall include in the list any technology, 
        treatment technique, or other means that is affordable, as 
        determined by the Administrator in consultation with the States, 
        for small public water systems serving--
                (I) a population of 10,000 or fewer but more than 3,300;
                (II) a population of 3,300 or fewer but more than 500; 
            and
                (III) a population of 500 or fewer but more than 25;

        and that achieves compliance with the maximum contaminant level 
        or treatment technique, including packaged or modular systems 
        and point-of-entry or point-of-use treatment units. Point-of-
        entry and point-of-use treatment units shall be owned, 
        controlled and maintained by the public water system or by a 
        person under contract with the public water system to ensure 
        proper operation and maintenance and compliance with the maximum 
        contaminant level or treatment technique and equipped with 
        mechanical warnings to ensure that customers are automatically 
        notified of operational problems. The Administrator shall not 
        include in the list any point-of-use treatment technology, 
        treatment technique, or other means to achieve compliance with a 
        maximum contaminant level or treatment technique requirement for 
        a microbial contaminant (or an indicator of a microbial 
        contaminant). If the American National Standards Institute has 
        issued product standards applicable to a specific type of point-
        of-entry or point-of-use treatment unit, individual units of 
        that type shall not be accepted for compliance with a maximum 
        contaminant level or treatment technique requirement unless they 
        are independently certified in accordance with such standards. 
        In listing any technology, treatment technique, or other means 
        pursuant to this clause, the Administrator shall consider the 
        quality of the source water to be treated.
            (iii) List of technologies that achieve compliance.--Except 
        as provided in clause (v), not later than 2 years after August 
        6, 1996, and after consultation with the States, the 
        Administrator shall issue a list of technologies that achieve 
        compliance with the maximum contaminant level or treatment 
        technique for each category of public water systems described in 
        subclauses (I), (II), and (III) of clause (ii) for each national 
        primary drinking water regulation promulgated prior to June 19, 
        1986.
            (iv) Additional technologies.--The Administrator may, at any 
        time after a national primary drinking water regulation has been 
        promulgated, supplement the list of technologies describing 
        additional or new or innovative treatment technologies that meet 
        the requirements of this paragraph for categories of small 
        public water systems described in subclauses (I), (II), and 
        (III) of clause (ii) that are subject to the regulation.
            (v) Technologies that meet surface water treatment rule.--
        Within one year after August 6, 1996, the Administrator shall 
        list technologies that meet the Surface Water Treatment Rule for 
        each category of public water systems described in subclauses 
        (I), (II), and (III) of clause (ii).

    (5) Additional health risk considerations.--
        (A) In general.--Notwithstanding paragraph (4), the 
    Administrator may establish a maximum contaminant level for a 
    contaminant at a level other than the feasible level, if the 
    technology, treatment techniques, and other means used to determine 
    the feasible level would result in an increase in the health risk 
    from drinking water by--
            (i) increasing the concentration of other contaminants in 
        drinking water; or
            (ii) interfering with the efficacy of drinking water 
        treatment techniques or processes that are used to comply with 
        other national primary drinking water regulations.

        (B) Establishment of level.--If the Administrator establishes a 
    maximum contaminant level or levels or requires the use of treatment 
    techniques for any contaminant or contaminants pursuant to the 
    authority of this paragraph--
            (i) the level or levels or treatment techniques shall 
        minimize the overall risk of adverse health effects by balancing 
        the risk from the contaminant and the risk from other 
        contaminants the concentrations of which may be affected by the 
        use of a treatment technique or process that would be employed 
        to attain the maximum contaminant level or levels; and
            (ii) the combination of technology, treatment techniques, or 
        other means required to meet the level or levels shall not be 
        more stringent than is feasible (as defined in paragraph 
        (4)(D)).

    (6) Additional health risk reduction and cost considerations.--
        (A) In general.--Notwithstanding paragraph (4), if the 
    Administrator determines based on an analysis conducted under 
    paragraph (3)(C) that the benefits of a maximum contaminant level 
    promulgated in accordance with paragraph (4) would not justify the 
    costs of complying with the level, the Administrator may, after 
    notice and opportunity for public comment, promulgate a maximum 
    contaminant level for the contaminant that maximizes health risk 
    reduction benefits at a cost that is justified by the benefits.
        (B) Exception.--The Administrator shall not use the authority of 
    this paragraph to promulgate a maximum contaminant level for a 
    contaminant, if the benefits of compliance with a national primary 
    drinking water regulation for the contaminant that would be 
    promulgated in accordance with paragraph (4) experienced by--
            (i) persons served by large public water systems; and
            (ii) persons served by such other systems as are unlikely, 
        based on information provided by the States, to receive a 
        variance under section 300g-4(e) of this title (relating to 
        small system variances);

    would justify the costs to the systems of complying with the 
    regulation. This subparagraph shall not apply if the contaminant is 
    found almost exclusively in small systems eligible under section 
    300g-4(e) of this title for a small system variance.
        (C) Disinfectants and disinfection byproducts.--The 
    Administrator may not use the authority of this paragraph to 
    establish a maximum contaminant level in a Stage I or Stage II 
    national primary drinking water regulation (as described in 
    paragraph (2)(C)) for contaminants that are disinfectants or 
    disinfection byproducts, or to establish a maximum contaminant level 
    or treatment technique requirement for the control of 
    cryptosporidium. The authority of this paragraph may be used to 
    establish regulations for the use of disinfection by systems relying 
    on ground water sources as required by paragraph (8).
        (D) Judicial review.--A determination by the Administrator that 
    the benefits of a maximum contaminant level or treatment requirement 
    justify or do not justify the costs of complying with the level 
    shall be reviewed by the court pursuant to section 300j-7 of this 
    title only as part of a review of a final national primary drinking 
    water regulation that has been promulgated based on the 
    determination and shall not be set aside by the court under that 
    section unless the court finds that the determination is arbitrary 
    and capricious.

    (7)(A) The Administrator is authorized to promulgate a national 
primary drinking water regulation that requires the use of a treatment 
technique in lieu of establishing a maximum contaminant level, if the 
Administrator makes a finding that it is not economically or 
technologically feasible to ascertain the level of the contaminant. In 
such case, the Administrator shall identify those treatment techniques 
which, in the Administrator's judgment, would prevent known or 
anticipated adverse effects on the health of persons to the extent 
feasible. Such regulations shall specify each treatment technique known 
to the Administrator which meets the requirements of this paragraph, but 
the Administrator may grant a variance from any specified treatment 
technique in accordance with section 300g-4(a)(3) of this title.
    (B) Any schedule referred to in this subsection for the promulgation 
of a national primary drinking water regulation for any contaminant 
shall apply in the same manner if the regulation requires a treatment 
technique in lieu of establishing a maximum contaminant level.
    (C)(i) Not later than 18 months after June 19, 1986, the 
Administrator shall propose and promulgate national primary drinking 
water regulations specifying criteria under which filtration (including 
coagulation and sedimentation, as appropriate) is required as a 
treatment technique for public water systems supplied by surface water 
sources. In promulgating such rules, the Administrator shall consider 
the quality of source waters, protection afforded by watershed 
management, treatment practices (such as disinfection and length of 
water storage) and other factors relevant to protection of health.
    (ii) In lieu of the provisions of section 300g-4 of this title the 
Administrator shall specify procedures by which the State determines 
which public water systems within its jurisdiction shall adopt 
filtration under the criteria of clause (i). The State may require the 
public water system to provide studies or other information to assist in 
this determination. The procedures shall provide notice and opportunity 
for public hearing on this determination. If the State determines that 
filtration is required, the State shall prescribe a schedule for 
compliance by the public water system with the filtration requirement. A 
schedule shall require compliance within 18 months of a determination 
made under clause (iii).
    (iii) Within 18 months from the time that the Administrator 
establishes the criteria and procedures under this subparagraph, a State 
with primary enforcement responsibility shall adopt any necessary 
regulations to implement this subparagraph. Within 12 months of adoption 
of such regulations the State shall make determinations regarding 
filtration for all the public water systems within its jurisdiction 
supplied by surface waters.
    (iv) If a State does not have primary enforcement responsibility for 
public water systems, the Administrator shall have the same authority to 
make the determination in clause (ii) in such State as the State would 
have under that clause. Any filtration requirement or schedule under 
this subparagraph shall be treated as if it were a requirement of a 
national primary drinking water regulation.
    (v) As an additional alternative to the regulations promulgated 
pursuant to clauses (i) and (iii), including the criteria for avoiding 
filtration contained in 40 CFR 141.71, a State exercising primary 
enforcement responsibility for public water systems may, on a case-by-
case basis, and after notice and opportunity for public comment, 
establish treatment requirements as an alternative to filtration in the 
case of systems having uninhabited, undeveloped watersheds in 
consolidated ownership, and having control over access to, and 
activities in, those watersheds, if the State determines (and the 
Administrator concurs) that the quality of the source water and the 
alternative treatment requirements established by the State ensure 
greater removal or inactivation efficiencies of pathogenic organisms for 
which national primary drinking water regulations have been promulgated 
or that are of public health concern than would be achieved by the 
combination of filtration and chlorine disinfection (in compliance with 
this section).
    (8) Disinfection.--At any time after the end of the 3-year period 
that begins on August 6, 1996, but not later than the date on which the 
Administrator promulgates a Stage II rulemaking for disinfectants and 
disinfection byproducts (as described in paragraph (2)(C)), the 
Administrator shall also promulgate national primary drinking water 
regulations requiring disinfection as a treatment technique for all 
public water systems, including surface water systems and, as necessary, 
ground water systems. After consultation with the States, the 
Administrator shall (as part of the regulations) promulgate criteria 
that the Administrator, or a State that has primary enforcement 
responsibility under section 300g-2 of this title, shall apply to 
determine whether disinfection shall be required as a treatment 
technique for any public water system served by ground water. The 
Administrator shall simultaneously promulgate a rule specifying criteria 
that will be used by the Administrator (or delegated State authorities) 
to grant variances from this requirement according to the provisions of 
sections 300g-4(a)(1)(B) and 300g-4(a)(3) of this title. In implementing 
section 300j-1(e) of this title the Administrator or the delegated State 
authority shall, where appropriate, give special consideration to 
providing technical assistance to small public water systems in 
complying with the regulations promulgated under this paragraph.
    (9) Review and revision.--The Administrator shall, not less often 
than every 6 years, review and revise, as appropriate, each national 
primary drinking water regulation promulgated under this subchapter. Any 
revision of a national primary drinking water regulation shall be 
promulgated in accordance with this section, except that each revision 
shall maintain, or provide for greater, protection of the health of 
persons.
    (10) Effective date.--A national primary drinking water regulation 
promulgated under this section (and any amendment thereto) shall take 
effect on the date that is 3 years after the date on which the 
regulation is promulgated unless the Administrator determines that an 
earlier date is practicable, except that the Administrator, or a State 
(in the case of an individual system), may allow up to 2 additional 
years to comply with a maximum contaminant level or treatment technique 
if the Administrator or State (in the case of an individual system) 
determines that additional time is necessary for capital improvements.
    (11) No national primary drinking water regulation may require the 
addition of any substance for preventive health care purposes unrelated 
to contamination of drinking water.
    (12) Certain contaminants.--
        (A) Arsenic.--
            (i) Schedule and standard.--Notwithstanding the deadlines 
        set forth in paragraph (1), the Administrator shall promulgate a 
        national primary drinking water regulation for arsenic pursuant 
        to this subsection, in accordance with the schedule established 
        by this paragraph.
            (ii) Study plan.--Not later than 180 days after August 6, 
        1996, the Administrator shall develop a comprehensive plan for 
        study in support of drinking water rulemaking to reduce the 
        uncertainty in assessing health risks associated with exposure 
        to low levels of arsenic. In conducting such study, the 
        Administrator shall consult with the National Academy of 
        Sciences, other Federal agencies, and interested public and 
        private entities.
            (iii) Cooperative agreements.--In carrying out the study 
        plan, the Administrator may enter into cooperative agreements 
        with other Federal agencies, State and local governments, and 
        other interested public and private entities.
            (iv) Proposed regulations.--The Administrator shall propose 
        a national primary drinking water regulation for arsenic not 
        later than January 1, 2000.
            (v) Final regulations.--Not later than January 1, 2001, 
        after notice and opportunity for public comment, the 
        Administrator shall promulgate a national primary drinking water 
        regulation for arsenic.
            (vi) Authorization.--There are authorized to be appropriated 
        $2,500,000 for each of fiscal years 1997 through 2000 for the 
        studies required by this paragraph.

        (B) Sulfate.--
            (i) Additional study.--Prior to promulgating a national 
        primary drinking water regulation for sulfate, the Administrator 
        and the Director of the Centers for Disease Control and 
        Prevention shall jointly conduct an additional study to 
        establish a reliable dose-response relationship for the adverse 
        human health effects that may result from exposure to sulfate in 
        drinking water, including the health effects that may be 
        experienced by groups within the general population (including 
        infants and travelers) that are potentially at greater risk of 
        adverse health effects as the result of such exposure. The study 
        shall be conducted in consultation with interested States, shall 
        be based on the best available, peer-reviewed science and 
        supporting studies conducted in accordance with sound and 
        objective scientific practices, and shall be completed not later 
        than 30 months after August 6, 1996.
            (ii) Determination.--The Administrator shall include sulfate 
        among the 5 or more contaminants for which a determination is 
        made pursuant to paragraph (3)(B) not later than 5 years after 
        August 6, 1996.
            (iii) Proposed and final rule.--Notwithstanding the 
        deadlines set forth in paragraph (2), the Administrator may, 
        pursuant to the authorities of this subsection and after notice 
        and opportunity for public comment, promulgate a final national 
        primary drinking water regulation for sulfate. Any such 
        regulation shall include requirements for public notification 
        and options for the provision of alternative water supplies to 
        populations at risk as a means of complying with the regulation 
        in lieu of a best available treatment technology or other means.

    (13) Radon in drinking water.--
        (A) National primary drinking water regulation.--Notwithstanding 
    paragraph (2), the Administrator shall withdraw any national primary 
    drinking water regulation for radon proposed prior to August 6, 
    1996, and shall propose and promulgate a regulation for radon under 
    this section, as amended by the Safe Drinking Water Act Amendments 
    of 1996.
        (B) Risk assessment and studies.--
            (i) Assessment by nas.--Prior to proposing a national 
        primary drinking water regulation for radon, the Administrator 
        shall arrange for the National Academy of Sciences to prepare a 
        risk assessment for radon in drinking water using the best 
        available science in accordance with the requirements of 
        paragraph (3). The risk assessment shall consider each of the 
        risks associated with exposure to radon from drinking water and 
        consider studies on the health effects of radon at levels and 
        under conditions likely to be experienced through residential 
        exposure. The risk assessment shall be peer-reviewed.
            (ii) Study of other measures.--The Administrator shall 
        arrange for the National Academy of Sciences to prepare an 
        assessment of the health risk reduction benefits associated with 
        various mitigation measures to reduce radon levels in indoor 
        air. The assessment may be conducted as part of the risk 
        assessment authorized by clause (i) and shall be used by the 
        Administrator to prepare the guidance and approve State programs 
        under subparagraph (G).
            (iii) Other organization.--If the National Academy of 
        Sciences declines to prepare the risk assessment or studies 
        required by this subparagraph, the Administrator shall enter 
        into a contract or cooperative agreement with another 
        independent, scientific organization to prepare such assessments 
        or studies.

        (C) Health risk reduction and cost analysis.--Not later than 30 
    months after August 6, 1996, the Administrator shall publish, and 
    seek public comment on, a health risk reduction and cost analysis 
    meeting the requirements of paragraph (3)(C) for potential maximum 
    contaminant levels that are being considered for radon in drinking 
    water. The Administrator shall include a response to all significant 
    public comments received on the analysis with the preamble for the 
    proposed rule published under subparagraph (D).
        (D) Proposed regulation.--Not later than 36 months after August 
    6, 1996, the Administrator shall propose a maximum contaminant level 
    goal and a national primary drinking water regulation for radon 
    pursuant to this section.
        (E) Final regulation.--Not later than 12 months after the date 
    of the proposal under subparagraph (D), the Administrator shall 
    publish a maximum contaminant level goal and promulgate a national 
    primary drinking water regulation for radon pursuant to this section 
    based on the risk assessment prepared pursuant to subparagraph (B) 
    and the health risk reduction and cost analysis published pursuant 
    to subparagraph (C). In considering the risk assessment and the 
    health risk reduction and cost analysis in connection with the 
    promulgation of such a standard, the Administrator shall take into 
    account the costs and benefits of control programs for radon from 
    other sources.
        (F) Alternative maximum contaminant level.--If the maximum 
    contaminant level for radon in drinking water promulgated pursuant 
    to subparagraph (E) is more stringent than necessary to reduce the 
    contribution to radon in indoor air from drinking water to a 
    concentration that is equivalent to the national average 
    concentration of radon in outdoor air, the Administrator shall, 
    simultaneously with the promulgation of such level, promulgate an 
    alternative maximum contaminant level for radon that would result in 
    a contribution of radon from drinking water to radon levels in 
    indoor air equivalent to the national average concentration of radon 
    in outdoor air. If the Administrator promulgates an alternative 
    maximum contaminant level under this subparagraph, the Administrator 
    shall, after notice and opportunity for public comment and in 
    consultation with the States, publish guidelines for State programs, 
    including criteria for multimedia measures to mitigate radon levels 
    in indoor air, to be used by the States in preparing programs under 
    subparagraph (G). The guidelines shall take into account data from 
    existing radon mitigation programs and the assessment of mitigation 
    measures prepared under subparagraph (B).
        (G) Multimedia radon mitigation programs.--
            (i) In general.--A State may develop and submit a multimedia 
        program to mitigate radon levels in indoor air for approval by 
        the Administrator under this subparagraph. If, after notice and 
        the opportunity for public comment, such program is approved by 
        the Administrator, public water systems in the State may comply 
        with the alternative maximum contaminant level promulgated under 
        subparagraph (F) in lieu of the maximum contaminant level in the 
        national primary drinking water regulation promulgated under 
        subparagraph (E).
            (ii) Elements of programs.--State programs may rely on a 
        variety of mitigation measures including public education, 
        testing, training, technical assistance, remediation grant and 
        loan or incentive programs, or other regulatory or nonregulatory 
        measures. The effectiveness of elements in State programs shall 
        be evaluated by the Administrator based on the assessment 
        prepared by the National Academy of Sciences under subparagraph 
        (B) and the guidelines published by the Administrator under 
        subparagraph (F).
            (iii) Approval.--The Administrator shall approve a State 
        program submitted under this paragraph if the health risk 
        reduction benefits expected to be achieved by the program are 
        equal to or greater than the health risk reduction benefits that 
        would be achieved if each public water system in the State 
        complied with the maximum contaminant level promulgated under 
        subparagraph (E). The Administrator shall approve or disapprove 
        a program submitted under this paragraph within 180 days of 
        receipt. A program that is not disapproved during such period 
        shall be deemed approved. A program that is disapproved may be 
        modified to address the objections of the Administrator and be 
        resubmitted for approval.
            (iv) Review.--The Administrator shall periodically, but not 
        less often than every 5 years, review each multimedia mitigation 
        program approved under this subparagraph to determine whether it 
        continues to meet the requirements of clause (iii) and shall, 
        after written notice to the State and an opportunity for the 
        State to correct any deficiency in the program, withdraw 
        approval of programs that no longer comply with such 
        requirements.
            (v) Extension.--If, within 90 days after the promulgation of 
        an alternative maximum contaminant level under subparagraph (F), 
        the Governor of a State submits a letter to the Administrator 
        committing to develop a multimedia mitigation program under this 
        subparagraph, the effective date of the national primary 
        drinking water regulation for radon in the State that would be 
        applicable under paragraph (10) shall be extended for a period 
        of 18 months.
            (vi) Local programs.--In the event that a State chooses not 
        to submit a multimedia mitigation program for approval under 
        this subparagraph or has submitted a program that has been 
        disapproved, any public water system in the State may submit a 
        program for approval by the Administrator according to the same 
        criteria, conditions, and approval process that would apply to a 
        State program. The Administrator shall approve a multimedia 
        mitigation program if the health risk reduction benefits 
        expected to be achieved by the program are equal to or greater 
        than the health risk reduction benefits that would result from 
        compliance by the public water system with the maximum 
        contaminant level for radon promulgated under subparagraph (E).

    (14) Recycling of filter backwash.--The Administrator shall 
promulgate a regulation to govern the recycling of filter backwash water 
within the treatment process of a public water system. The Administrator 
shall promulgate such regulation not later than 4 years after August 6, 
1996, unless such recycling has been addressed by the Administrator's 
Enhanced Surface Water Treatment Rule prior to such date.
    (15) Variance technologies.--
        (A) In general.--At the same time as the Administrator 
    promulgates a national primary drinking water regulation for a 
    contaminant pursuant to this section, the Administrator shall issue 
    guidance or regulations describing the best treatment technologies, 
    treatment techniques, or other means (referred to in this paragraph 
    as ``variance technology'') for the contaminant that the 
    Administrator finds, after examination for efficacy under field 
    conditions and not solely under laboratory conditions, are available 
    and affordable, as determined by the Administrator in consultation 
    with the States, for public water systems of varying size, 
    considering the quality of the source water to be treated. The 
    Administrator shall identify such variance technologies for public 
    water systems serving--
            (i) a population of 10,000 or fewer but more than 3,300;
            (ii) a population of 3,300 or fewer but more than 500; and
            (iii) a population of 500 or fewer but more than 25,

    if, considering the quality of the source water to be treated, no 
    treatment technology is listed for public water systems of that size 
    under paragraph (4)(E). Variance technologies identified by the 
    Administrator pursuant to this paragraph may not achieve compliance 
    with the maximum contaminant level or treatment technique 
    requirement of such regulation, but shall achieve the maximum 
    reduction or inactivation efficiency that is affordable considering 
    the size of the system and the quality of the source water. The 
    guidance or regulations shall not require the use of a technology 
    from a specific manufacturer or brand.
        (B) Limitation.--The Administrator shall not identify any 
    variance technology under this paragraph, unless the Administrator 
    has determined, considering the quality of the source water to be 
    treated and the expected useful life of the technology, that the 
    variance technology is protective of public health.
        (C) Additional information.--The Administrator shall include in 
    the guidance or regulations identifying variance technologies under 
    this paragraph any assumptions supporting the public health 
    determination referred to in subparagraph (B), where such 
    assumptions concern the public water system to which the technology 
    may be applied, or its source waters. The Administrator shall 
    provide any assumptions used in determining affordability, taking 
    into consideration the number of persons served by such systems. The 
    Administrator shall provide as much reliable information as 
    practicable on performance, effectiveness, limitations, costs, and 
    other relevant factors including the applicability of variance 
    technology to waters from surface and underground sources.
        (D) Regulations and guidance.--Not later than 2 years after 
    August 6, 1996, and after consultation with the States, the 
    Administrator shall issue guidance or regulations under subparagraph 
    (A) for each national primary drinking water regulation promulgated 
    prior to August 6, 1996, for which a variance may be granted under 
    section 300g-4(e) of this title. The Administrator may, at any time 
    after a national primary drinking water regulation has been 
    promulgated, issue guidance or regulations describing additional 
    variance technologies. The Administrator shall, not less often than 
    every 7 years, or upon receipt of a petition supported by 
    substantial information, review variance technologies identified 
    under this paragraph. The Administrator shall issue revised guidance 
    or regulations if new or innovative variance technologies become 
    available that meet the requirements of this paragraph and achieve 
    an equal or greater reduction or inactivation efficiency than the 
    variance technologies previously identified under this subparagraph. 
    No public water system shall be required to replace a variance 
    technology during the useful life of the technology for the sole 
    reason that a more efficient variance technology has been listed 
    under this subparagraph.

(c) Secondary regulations; publication of proposed regulations; 
        promulgation; amendments

    The Administrator shall publish proposed national secondary drinking 
water regulations within 270 days after December 16, 1974. Within 90 
days after publication of any such regulation, he shall promulgate such 
regulation with such modifications as he deems appropriate. Regulations 
under this subsection may be amended from time to time.

(d) Regulations; public hearings; administrative consultations

    Regulations under this section shall be prescribed in accordance 
with section 553 of title 5 (relating to rulemaking), except that the 
Administrator shall provide opportunity for public hearing prior to 
promulgation of such regulations. In proposing and promulgating 
regulations under this section, the Administrator shall consult with the 
Secretary and the National Drinking Water Advisory Council.

(e) Science Advisory Board comments

    The Administrator shall request comments from the Science Advisory 
Board (established under the Environmental Research, Development, and 
Demonstration Act of 1978) prior to proposal of a maximum contaminant 
level goal and national primary drinking water regulation. The Board 
shall respond, as it deems appropriate, within the time period 
applicable for promulgation of the national primary drinking water 
standard concerned. This subsection shall, under no circumstances, be 
used to delay final promulgation of any national primary drinking water 
standard.

(July 1, 1944, ch. 373, title XIV, Sec. 1412, as added Pub. L. 93-523, 
Sec. 2(a), Dec. 16, 1974, 88 Stat. 1662; amended Pub. L. 95-190, 
Secs. 3(c), 12(a), Nov. 16, 1977, 91 Stat. 1394, 1398; Pub. L. 99-339, 
title I, Sec. 101(a)-(c)(1), (d), (e), June 19, 1986, 100 Stat. 642-646; 
Pub. L. 104-182, title I, Secs. 102(a), (c)(2), 103, 104(a), (c), 105-
111(a), title V, Sec. 501(a)(1), (2), Aug. 6, 1996, 110 Stat. 1617, 
1621-1623, 1625-1631, 1691.)

                       References in Text

    The Federal Insecticide, Fungicide, and Rodenticide Act, referred to 
in subsec. (b)(1)(B)(i)(II), is act June 25, 1947, ch. 125, as amended 
generally by Pub. L. 92-516, Oct. 21, 1972, 86 Stat. 973, which is 
classified generally to subchapter II (Sec. 136 et seq.) of chapter 6 of 
Title 7, Agriculture. For complete classification of this Act to the 
Code, see Short Title note set out under section 136 of Title 7 and 
Tables.
    The Safe Drinking Water Act Amendments of 1996, referred to in 
subsec. (b)(13)(A), is Pub. L. 104-182, Aug. 6, 1996, 110 Stat. 1613. 
For complete classification of this Act to the Code, see Short Title of 
1996 Amendment note set out under section 201 of this title and Tables.
    The Environmental Research, Development, and Demonstration Act of 
1978, referred to in subsec. (e), probably means the Environmental 
Research, Development, and Demonstration Authorization Act of 1978 which 
is Pub. L. 95-155, Nov. 8, 1977, 91 Stat. 1257, as amended. Provisions 
of the Act establishing the Science Advisory Board are classified to 
section 4365 of this title. For complete classification of this Act to 
the Code, see Tables.


                               Amendments

    1996--Subsec. (a)(3). Pub. L. 104-182, Sec. 102(c)(2), struck out 
``paragraph (1), (2), or (3) of'' before ``subsection (b)'' in two 
places.
    Subsec. (b). Pub. L. 104-182, Sec. 102(a), inserted heading.
    Subsec. (b)(1), (2). Pub. L. 104-182, Sec. 102(a), added pars. (1) 
and (2) and struck out former pars. (1) and (2) which related to 
publication of maximum contaminant level goals and promulgation of 
national primary drinking water regulations for certain listed 
contaminants or substituted contaminants.
    Subsec. (b)(3). Pub. L. 104-182, Sec. 103, added par. (3).
    Pub. L. 104-182, Sec. 102(a), struck out par. (3) which related to 
publication of maximum contaminant level goals and promulgation of 
national primary drinking water regulations for contaminants, other than 
those referred to in pars. (1) or (2), which may have an adverse effect 
on human health and are known to occur in public water systems.
    Subsec. (b)(4). Pub. L. 104-182, Sec. 104(a)(1), designated first 
sentence as subpar. (A), inserted par. and subpar. (A) headings, 
designated second sentence as subpar. (B), inserted subpar. (B) heading, 
substituted ``Except as provided in paragraphs (5) and (6), each 
national'' for ``Each national'' and ``specify a maximum contaminant 
level'' for ``specify a maximum level'', and added subpar. (C).
    Subsec. (b)(4)(D). Pub. L. 104-182, Sec. 104(a)(2), (3), 
redesignated par. (5) as subpar. (D) of par. (4), inserted subpar. 
heading, and substituted ``this paragraph'' for ``paragraph (4)''.
    Subsec. (b)(4)(E). Pub. L. 104-182, Secs. 104(a)(4), (5), 105, 
redesignated par. (6) as subpar. (E)(i) of par. (4), inserted subpar. 
and cl. headings, substituted ``this subsection'' for ``this 
paragraph'', and added cls. (ii) to (v).
    Subsec. (b)(5), (6). Pub. L. 104-182, Sec. 104(a)(6), added pars. 
(5) and (6). Former pars. (5) and (6) redesignated subpars. (D) and 
(E)(i), respectively, of par. (4).
    Subsec. (b)(7)(C)(v). Pub. L. 104-182, Sec. 106, added cl. (v).
    Subsec. (b)(8). Pub. L. 104-182, Sec. 501(a)(2), substituted 
``section 300j-1(e)'' for ``section 300j-1(g)''.
    Pub. L. 104-182, Sec. 107, inserted heading, realigned margins, and 
substituted ``At any time after the end of the 3-year period that begins 
on August 6, 1996, but not later than the date on which the 
Administrator promulgates a Stage II rulemaking for disinfectants and 
disinfection byproducts (as described in paragraph (2)(C)), the 
Administrator shall also promulgate national primary drinking water 
regulations requiring disinfection as a treatment technique for all 
public water systems, including surface water systems and, as necessary, 
ground water systems. After consultation with the States, the 
Administrator shall (as part of the regulations) promulgate criteria 
that the Administrator, or a State that has primary enforcement 
responsibility under section 300g-2 of this title, shall apply to 
determine whether disinfection shall be required as a treatment 
technique for any public water system served by ground water.'' for 
``Not later than 36 months after June 19, 1986, the Administrator shall 
propose and promulgate national primary drinking water regulations 
requiring disinfection as a treatment technique for all public water 
systems.''
    Subsec. (b)(9). Pub. L. 104-182, Sec. 104(c), amended par. (9) 
generally. Prior to amendment, par. (9) read as follows: ``National 
primary drinking water regulations shall be amended whenever changes in 
technology, treatment techniques, and other means permit greater 
protection of the health of persons, but in any event such regulations 
shall be reviewed at least once every 3 years. Such review shall include 
an analysis of innovations or changes in technology, treatment 
techniques or other activities that have occurred over the previous 3-
year period and that may provide for greater protection of the health of 
persons. The findings of such review shall be published in the Federal 
Register. If, after opportunity for public comment, the Administrator 
concludes that the technology, treatment techniques, or other means 
resulting from such innovations or changes are not feasible within the 
meaning of paragraph (5), an explanation of such conclusion shall be 
published in the Federal Register.''
    Subsec. (b)(10). Pub. L. 104-182, Sec. 108, amended par. (10) 
generally. Prior to amendment, par. (10) read as follows: ``National 
primary drinking water regulations promulgated under this subsection 
(and amendments thereto) shall take effect eighteen months after the 
date of their promulgation. Regulations under subsection (a) of this 
section shall be superseded by regulations under this subsection to the 
extent provided by the regulations under this subsection.''
    Subsec. (b)(11). Pub. L. 104-182, Sec. 501(a)(1), realigned margins.
    Subsec. (b)(12). Pub. L. 104-182, Sec. 109(a), added par. (12).
    Subsec. (b)(13). Pub. L. 104-182, Sec. 109(b), added par. (13).
    Subsec. (b)(14). Pub. L. 104-182, Sec. 110, added par. (14).
    Subsec. (b)(15). Pub. L. 104-182, Sec. 111(a), added par. (15).
    1986--Subsec. (a). Pub. L. 99-339, Sec. 101(a), amended subsec. (a) 
generally. Prior to amendment, subsec. (a) read as follows:
    ``(1) The Administrator shall publish proposed national interim 
primary drinking water regulations within 90 days after December 16, 
1974. Within 180 days after December 16, 1974, he shall promulgate such 
regulations with such modifications as he deems appropriate. Regulations 
under this paragraph may be amended from time to time.
    ``(2) National interim primary drinking water regulations 
promulgated under paragraph (1) shall protect health to the extent 
feasible, using technology, treatment techniques, and other means, which 
the Administrator determines are generally available (taking costs into 
consideration) on December 16, 1974.
    ``(3) The interim primary regulations first promulgated under 
paragraph (1) shall take effect eighteen months after the date of their 
promulgation.''
    Subsec. (b)(1). Pub. L. 99-339, Sec. 101(b), substituted provisions 
establishing standard setting schedules and deadlines for provisions 
relating to establishment of maximum contaminant levels and a list of 
contaminants with adverse effect but of undetermined levels.
    Subsec. (b)(2). Pub. L. 99-339, Sec. 101(b), substituted provisions 
authorizing the Administrator to substitute contaminants for those 
referred to in par. (1) and to supply a list of the contaminants 
proposed for substitution, with the decision of the Administrator to 
regulate such contaminant not subject to judicial review, for provisions 
which authorized the Administrator to publish in the Federal Register 
proposed revised national interim primary drinking water regulations and 
180 days after the date of such proposed regulations to promulgate such 
revised regulations with modification as deemed appropriate.
    Subsec. (b)(3). Pub. L. 99-339, Sec. 101(b), substituted provisions 
directing the Administrator to publish maximum contaminant level goals 
and promulgate national primary drinking water regulations for 
contaminants, other than specified in par. (1) or (2), which may have an 
adverse effect on health and are known or anticipated to occur in public 
water systems, to establish an advisory working group to aid in 
establishing a list of such contaminants, and to publish, within a 
specified time, both proposed and final goals and regulations for 
provisions which required that revised national primary drinking water 
regulations specify a maximum contaminant level or require the use of 
treatment techniques for each contaminant, which level or technique was 
to be as close to the recommended level or technique as feasible, and 
defined the term ``feasible''.
    Subsec. (b)(4) to (11). Pub. L. 99-339, Sec. 101(b), (c)(1), (d), 
added pars. (4) to (8), redesignated former pars. (4) to (6) as pars. 
(9) to (11), respectively, in par. (9) substituted ``National'' for 
``Revised National'' and inserted provision that review include 
analysis, and publication in Federal Register, of innovations in 
technology, treatment techniques or other activities occurring during 
previous three years and their feasibility, and in par. (10) substituted 
``National'' for ``Revised National''.
    Subsec. (e). Pub. L. 99-339, Sec. 101(e), amended subsec. (e) 
generally, substituting provisions which relate to the request by the 
Administrator of comments by the Science Advisory Board prior to 
proposal of a maximum contaminant level goal and national primary 
drinking water regulation for provisions which related to study by the 
National Academy of Sciences to determine the maximum contaminant 
levels, report to Congress, and funding therefor.
    1977--Subsec. (e)(2). Pub. L. 95-190 inserted provisions relating to 
revisions of the required report and cl. (G).


                   Applicability of Prior Requirements

    Section 102(b) of Pub. L. 104-182 provided that: ``The requirements 
of subparagraphs (C) and (D) of section 1412(b)(3) of the Safe Drinking 
Water Act [subsec. (b)(3)(C), (D) of this section] as in effect before 
the date of enactment of this Act [Aug. 6, 1996], and any obligation to 
promulgate regulations pursuant to such subparagraphs not promulgated as 
of the date of enactment of this Act, are superseded by the amendments 
made by subsection (a) [amending this section].''


                Disinfectants and Disinfection Byproducts

    Section 104(b) of Pub. L. 104-182 provided that: ``The Administrator 
of the Environmental Protection Agency may use the authority of section 
1412(b)(5) of the Safe Drinking Water Act [subsec. (b)(5) of this 
section] (as amended by this Act) to promulgate the Stage I and Stage II 
Disinfectants and Disinfection Byproducts Rules as proposed in volume 
59, Federal Register, page 38668 (July 29, 1994). The considerations 
used in the development of the July 29, 1994, proposed national primary 
drinking water regulation on disinfectants and disinfection byproducts 
shall be treated as consistent with such section 1412(b)(5) for purposes 
of such Stage I and Stage II rules.''

                  Section Referred to in Other Sections

    This section is referred to in sections 300f, 300g-2, 300g-3, 300g-
4, 300g-5, 300j-2, 300j-3, 300j-3b, 300j-4, 300j-12, 300j-14 of this 
title; title 21 section 349.
