Maximum contaminant levels (MCLs) are standards that are set by the United States Environmental Protection Agency (EPA) for drinking water quality. [1] [2] An MCL is the legal threshold limit on the amount of a substance that is allowed in public water systems under the Safe Drinking Water Act (SDWA). The limit is usually expressed as a concentration in milligrams or micrograms per liter of water. [3]
To set a maximum contaminant level for a contaminant, EPA first determines how much of the contaminant may be present with no adverse health effects. This level is called the maximum contaminant level goal (MCLG). MCLGs are non-enforceable public health goals. The legally enforced MCL is then set as close as possible to the MCLG. The MCL for a contaminant may be higher than the MCLG because of difficulties in measuring small quantities of a contaminant, a lack of available treatment technologies, or if EPA determines that the costs of treatment would outweigh the public health benefits of a lower MCL. In the last case, EPA is permitted to choose an MCL that balances the cost of treatment with the public health benefits. [4] MCLs require monitoring, remediation, and public notice when standards are exceeded. [2] As of 2019 EPA has issued 88 standards (78 MCLs and 10 Treatment Techniques) for microorganisms, chemicals and radionuclides. [5]
For some contaminants, EPA establishes a Treatment Technique (TT) instead of an MCL. TTs are enforceable procedures that drinking water systems must follow in treating their water for a contaminant. [4]
MCLs and TTs are known jointly as "National Primary Drinking Water Regulations" (NPDWRs), or primary standards. [6]
Some contaminants may cause aesthetic problems with drinking water, such as the presence of unpleasant tastes or odors, or cosmetic problems, such as tooth discoloration. Since these contaminants do not cause health problems, there are no legally enforceable limits on their presence in drinking water. However, EPA recommends maximum levels of these contaminants in drinking water. These recommendations are called "National Secondary Drinking Water Regulations" (NSDWRs), or secondary standards. [4] [7]
Some state laws and regulations use the term "maximum contaminant level" to refer to MCLs promulgated within a state pursuant either to the federal SDWA or state law; for example, the New Jersey Safe Drinking Water Act. [8] In some cases, a state may issue an MCL for a contaminant that has not been regulated by EPA under federal law. For example, in 2018 New Jersey promulgated an MCL for perfluorononanoic acid (PFNA). [9] [10]
Passamaquoddy Pleasant Point Reservation is one of two reservations of the federally recognized Passamaquoddy tribe in Washington County, Maine, United States. The population was 692 as of the 2020 census.
Drinking water or potable water is water that is safe for ingestion, either when drunk directly in liquid form or consumed indirectly through food preparation. It is often supplied through taps, in which case it is also called tap water. Typically in developed countries, tap water meets drinking water quality standards, even though only a small proportion is actually consumed or used in food preparation. Other typical uses for tap water include washing, toilets, and irrigation. Greywater may also be used for toilets or irrigation. Its use for irrigation however may be associated with risks.
Lindane, also known as gamma-hexachlorocyclohexane (γ-HCH), gammaxene, Gammallin and benzene hexachloride (BHC), is an organochlorine chemical and an isomer of hexachlorocyclohexane that has been used both as an agricultural insecticide and as a pharmaceutical treatment for lice and scabies.
The Resource Conservation and Recovery Act (RCRA), enacted in 1976, is the principal federal law in the United States governing the disposal of solid waste and hazardous waste.
Hexavalent chromium (chromium(VI), Cr(VI), chromium 6) is any chemical compound that contains the element in the +6 oxidation state (thus hexavalent). It has been identified as carcinogenic, which is of concern since approximately 136,000 tonnes (150,000 tons) of hexavalent chromium were produced in 1985. Hexavalent chromium compounds can be carcinogens (IARC Group 1), especially if airborne and inhaled where they can cause lung cancer.
The Safe Drinking Water Act (SDWA) is the principal federal law in the United States intended to ensure safe drinking water for the public. Pursuant to the act, the Environmental Protection Agency (EPA) is required to set standards for drinking water quality and oversee all states, localities, and water suppliers that implement the standards.
The Lead and Copper Rule (LCR) is a United States federal regulation that limits the concentration of lead and copper allowed in public drinking water at the consumer's tap, as well as limiting the permissible amount of pipe corrosion occurring due to the water itself. The U.S. Environmental Protection Agency (EPA) first issued the rule in 1991 pursuant to the Safe Drinking Water Act (SDWA). The EPA promulgated the regulations following studies that concluded that copper and lead have an adverse effect on individuals. The LCR limits the levels of these metals in water through improving water treatment centers, determining copper and lead levels for customers who use lead plumbing parts, and eliminating the water source as a source of lead and copper. If the lead and copper levels exceed the "action levels", water suppliers are required to educate their consumers on how to reduce exposure to lead. In a 2005 report EPA stated that the LCR requirements had been effective in 96 percent of systems serving at least 3,300 people.
In the United States, public drinking water is governed by the laws and regulations enacted by the federal and state governments. Certain ordinances may also be created at a more local level. The Safe Drinking Water Act (SDWA) is the principal federal law. The SDWA authorizes the United States Environmental Protection Agency (EPA) to create and enforce regulations to achieve the SDWA goals.
Water testing is a broad description for various procedures used to analyze water quality. Millions of water quality tests are carried out daily to fulfill regulatory requirements and to maintain safety.
Title 40 is a part of the United States Code of Federal Regulations. Title 40 arranges mainly environmental regulations that were promulgated by the US Environmental Protection Agency (EPA), based on the provisions of United States laws. Parts of the regulation may be updated annually on July 1.
Drinking water quality in the United States is generally safe. In 2016, over 90 percent of the nation's community water systems were in compliance with all published U.S. Environmental Protection Agency standards. Over 286 million Americans get their tap water from a community water system. Eight percent of the community water systems—large municipal water systems—provide water to 82 percent of the US population. The Safe Drinking Water Act requires the US EPA to set standards for drinking water quality in public water systems. Enforcement of the standards is mostly carried out by state health agencies. States may set standards that are more stringent than the federal standards.
Perfluorononanoic acid, or PFNA, is a synthetic perfluorinated carboxylic acid and fluorosurfactant that is also an environmental contaminant found in people and wildlife along with PFOS and PFOA.
Per- and polyfluoroalkyl substances are a group of synthetic organofluorine chemical compounds that have multiple fluorine atoms attached to an alkyl chain; there are 7 million such chemicals according to PubChem. PFAS came into use after the invention of Teflon in 1938 to make fluoropolymer coatings and products that resist heat, oil, stains, grease, and water. They are now used in products including waterproof fabric such as Nylon, yoga pants, carpets, shampoo, feminine hygiene products, mobile phone screens, wall paint, furniture, adhesives, food packaging, heat-resistant non-stick cooking surfaces such as Teflon, AstroTurf, firefighting foam, and the insulation of electrical wire. PFAS are also used by the cosmetic industry in most cosmetics and personal care products, including lipstick, eye liner, mascara, foundation, concealer, lip balm, blush, and nail polish.
The MTBE controversy concerns methyl tert-butyl ether (MTBE), a gasoline additive that replaced tetraethyllead. MTBE is an oxygenate and raises gasoline's octane number. Its use declined in the United States in response to environmental and health concerns. It has polluted groundwater due to MTBE-containing gasoline being spilled or leaked at gas stations. MTBE spreads more easily underground than other gasoline components due to its higher solubility in water. Cost estimates for removing MTBE from groundwater and contaminated soil range from $1 billion to $30 billion, including removing the compound from aquifers and municipal water supplies, and replacing leaky underground oil tanks. Who will pay for remediation is controversial. In one case, the cost to oil companies to clean up the MTBE in wells belonging to the city of Santa Monica, California is estimated to exceed $200 million.
Drinking water quality standards describes the quality parameters set for drinking water. Water may contain many harmful constituents, yet there are no universally recognized and accepted international standards for drinking water. Even where standards do exist, the permitted concentration of individual constituents may vary by as much as ten times from one set of standards to another. Many countries specify standards to be applied in their own country. In Europe, this includes the European Drinking Water Directive and in the United States, the United States Environmental Protection Agency (EPA) establishes standards as required by the Safe Drinking Water Act. China adopted its own drinking water standard GB3838-2002 enacted by Ministry of Environmental Protection in 2002. For countries without a legislative or administrative framework for such standards, the World Health Organization publishes guidelines on the standards that should be achieved.
Water quality laws govern the protection of water resources for human health and the environment. Water quality laws are legal standards or requirements governing water quality, that is, the concentrations of water pollutants in some regulated volume of water. Such standards are generally expressed as levels of a specific water pollutants that are deemed acceptable in the water volume, and are generally designed relative to the water's intended use - whether for human consumption, industrial or domestic use, recreation, or as aquatic habitat. Additionally, these laws provide regulations on the alteration of the chemical, physical, radiological, and biological characteristics of water resources. Regulatory efforts may include identifying and categorizing water pollutants, dictating acceptable pollutant concentrations in water resources, and limiting pollutant discharges from effluent sources. Regulatory areas include sewage treatment and disposal, industrial and agricultural waste water management, and control of surface runoff from construction sites and urban environments. Water quality laws provides the foundation for regulations in water standards, monitoring, required inspections and permits, and enforcement. These laws may be modified to meet current needs and priorities.
There are many exemptions for fracking under United States federal law: the oil and gas industries are exempt or excluded from certain sections of a number of the major federal environmental laws. These laws range from protecting clean water and air, to preventing the release of toxic substances and chemicals into the environment: the Clean Air Act, Clean Water Act, Safe Drinking Water Act, National Environmental Policy Act, Resource Conservation and Recovery Act, Emergency Planning and Community Right-to-Know Act, and the Comprehensive Environmental Response, Compensation, and Liability Act, commonly known as Superfund.
Water in Arkansas is an important issue encompassing the conservation, protection, management, distribution and use of the water resource in the state. Arkansas contains a mixture of groundwater and surface water, with a variety of state and federal agencies responsible for the regulation of the water resource. In accordance with agency rules, state, and federal law, the state's water treatment facilities utilize engineering, chemistry, science and technology to treat raw water from the environment to potable water standards and distribute it through water mains to homes, farms, business and industrial customers. Following use, wastewater is collected in collection and conveyance systems, decentralized sewer systems or septic tanks and treated in accordance with regulations at publicly owned treatment works (POTWs) before being discharged to the environment.
The Wellhead Protection Program in the 1986 amendments to the Safe Drinking Water Act requires states to protect underground sources of drinking water from contaminants that may adversely affect human health. Over half of the U.S. population relies on groundwater for drinking water However, residential, municipal, commercial, industrial, and agricultural activities can all contaminate groundwater. In the event of contamination, a community's drinking water supply can develop poor quality or be lost altogether. Groundwater contamination occurs from products such as oil, chemicals, gasoline, or other toxic substances to infiltrate groundwater. These products can travel through soil and seep into the groundwater; this process can occur through landfills, septic tanks, mining sites, fertilization, etc. Groundwater contamination might not be detected for a long period of time and health problems can occur from drinking contaminated water. Cleanup of a contaminated underground source of drinking water may be impossible or so difficult it costs thousands or millions of dollars. The U.S. Congress requiring Wellhead Protection Programs by 42 U.S.C. § 300h–7 in the Safe Drinking Water Act applied the concept that it is better to prevent groundwater contamination than try to remediate it. U.S. Congress by 42 U.S.C. § 300h–7 requires identification of the areas that need implementation of control measures in order to protect public water supply wells from contamination as "wellhead protection areas". Communities can use the police power established by the Tenth Amendment to the U.S. Constitution to enforce zoning and subdivision regulations to protect drinking water sources. Thereby communities can direct development away from areas that would pose a threat to drinking water sources.
Environmental law in New Jersey consists of legislative and regulatory efforts to protect the natural environment in the State of New Jersey. Such efforts include laws and regulations to reduce air and water pollution, regulate the purity of drinking water, remediate contaminated sites, and preserve lands from development, particularly in the Pinelands of southern New Jersey and the Highlands in the north of the state. Environmental laws in New Jersey are enforced primarily by the New Jersey Department of Environmental Protection (NJDEP).