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Water Quality - EPA Rules and Regulations

Federal Testing Requirements Under the Safe Drinking Water Act

  • The Safe Drinking Water Act (SDWA), passed in 1974 and amended in 1986 and 1996, gives the Environmental Protection Agency (EPA) the authority to set drinking water standards.
www.epa.gov/safewater/standard/setting.html
  • The EPA has a "multiple barrier" approach
    • assessing and protecting drinking water sources
    • protecting wells and collection systems
    • making sure water is treated by qualified operators
    • ensuring the integrity of distribution systems
    • making information available to the public on the quality of their drinking water
  • Drinking water standards apply to public water systems (PWSs), which provide water for human consumption through at least 15 service connections or regularly serve at least 25 individuals.
  • Public water systems include municipal water companies, homeowner associations, schools, businesses, campgrounds and shopping malls.
  • There are two categories of drinking water standards: Primary and Secondary.

National Primary Drinking Water Regulations

  • Primary Standards (NPDWRs) are legally-enforceable standards that apply to public water systems.
  • Primary Standards are classified and listed in the following categories:
    • Microorganisms
    • Disinfectants
    • Disinfection Byproducts
    • Inorganic Chemicals
    • Organic Chemicals
    • Radionuclides
  • Primary Standards protect drinking water quality by limiting the levels of specific contaminants that can adversely affect public health and are known or anticipated to occur in water.
    • Primary Standards are listed as Maximum Contaminant Levels or Treatment Techniques.

Maximum Contamination Levels (MCLs)

  • The Maximum Contamination Level (MCL) is the highest level of a contaminant that is allowed in drinking water.
    • MCLs are enforceable standards.
  • The EPA also sets a Maximum Contaminant Level Goal (MCLG), which is the maximum level of a contaminant in drinking water, delivered to any user of a public water system, at which no known or anticipated adverse effect on the health of persons would occur, and which allows an adequate margin of safety.
    • MCLGs are non-enforceable public health goals.

Treatment Techniques (TTs)

  • A Treatment Technique (TT) is an enforceable procedure or level of technological performance which public water systems must follow to ensure control of a contaminant.
    • A Treatment Technique (TT) is set, rather than an MCL, when there is no reliable method that is economically and technically feasible to measure a contaminant at particularly low concentrations,
  • Primary Standards, MCLs and Treatment Techniques

National Secondary Drinking Water Regulations

  • Secondary Standards (NSDWRs) are non-enforceable guidelines regarding contaminants that may cause cosmetic effects (such as skin or tooth discoloration) or aesthetic effects (such as taste, odor, or color) in drinking water.
    • The EPA recommends Secondary Standards to water systems but does not require systems to comply.
    • States may choose to adopt them as enforceable standards.
  • Secondary Standards

Contaminant Candidate Lists (CCLs)

  • The CCL is a list of unregulated contaminants which may require a national drinking water regulation in the future.
    • The EPA must periodically publish this list of contaminants (called the Contaminant Candidate List or CCL) and decide whether to regulate at least five or more contaminants on the list (called Regulatory Determinations).
    • EPA uses this list of unregulated contaminants to prioritize research and data collection efforts to help us determine whether we should regulate a specific contaminant.
  • CCL1 (1998 - Microbial and Chemical Contaminant Candidates)
  • CCL2 (2005 - Microbial and Chemical Contaminant Candidates)

City and Communal Water Systems

Consumer Confidence Reports (CCRs)

  • The EPA Consumer Confidence Rule requires public water suppliers that serve the same people year round (community water systems) to provide a Consumer Confidence Report (CCR) to their customers.
    • These reports are also known as annual water quality reports or drinking water quality reports.
  • The CCR summarizes information regarding sources used (i.e., rivers, lakes, reservoirs, or aquifers), any detected contaminants, compliance efforts, and educational information.
    • The reports are due to customers by July 1st of each year.
    • Non-government systems typically distribute CCRs only to subscribers.
  • City of Santa Fe Water Division 2007 Water Quality Report
  • Santa Fe County Water Resources Division 2007 Water Quality Report

Regulation of Private Wells

  • Private well water quality is NOT governed by EPA regulations.
  • The Office of the State Engineer issues a permit and requires the filing of a completion report under existing Rules and Regulations Governing the Drilling of Wells.
  • The Office of the State Engineer also oversees the Appropriation and Use of the Ground Water in New Mexico, per the New Mexico Administrative Code.
  • Primary and Secondary Standards for public systems are a useful guideline for the treatment of water in private wells.
  • EPA recommends testing private water supplies annually for nitrates, coliform bacteria, total dissolved solids (TDS), and pH levels to detect contamination problems early.