EPA Cracks Down on Perchlorate in Drinking Water
Published Date: 1/6/2026
Proposed Rule
Summary
The EPA is proposing new rules to limit perchlorate in drinking water to keep it safe and healthy for everyone. Water systems will need to test for perchlorate, fix problems if levels are too high, and share info with the public. These changes affect water providers nationwide, with public comments open until March 9, 2026, and could mean some costs but better health protection.
Analyzed Economic Effects
5 provisions identified: 2 benefits, 3 costs, 0 mixed.
New perchlorate limits proposed
The EPA proposes a health-based Maximum Contaminant Level Goal (MCLG) for perchlorate of 0.02 mg/L (20 micrograms per liter) and is seeking comment on enforceable Maximum Contaminant Levels (MCLs) of 0.02 mg/L (20 µg/L), 0.04 mg/L (40 µg/L), or 0.08 mg/L (80 µg/L). These standards would apply to public water systems and determine when systems must reduce perchlorate in drinking water.
New monitoring rules for water systems
The EPA would require community water systems (CWSs) and non-transient non-community water systems (NTNCWSs) to monitor drinking water for perchlorate, with monitoring frequency based on previous results and options to use previously collected data or reduced monitoring if initial samples are low. The proposal includes provisions to automatically reduce monitoring frequency for systems with low or non-detect results.
Required fixes when levels exceed MCL
If a public water system exceeds the perchlorate MCL, the system would need to mitigate the contamination by installing treatment (examples: ion exchange, reverse osmosis, biological treatment), switching to an uncontaminated source, or using certified point-of-use devices for small systems. Systems that exceed the MCL would also be required to report and take actions to come back into compliance.
EPA estimates nationwide costs exceed benefits
The EPA estimates annualized incremental nationwide costs and benefits (2023 dollars) for each MCL option: for a 20 µg/L MCL, annualized cost $16.1 million (3% discount) and monetized benefit $8.3 million (net -$7.8 million); for 40 µg/L, cost $11.2 million and benefit $6.8 million (net -$4.4 million); for 80 µg/L, cost $8.6 million and benefit $5.3 million (net -$3.3 million). The Agency concluded that monetized benefits do not justify the costs for any of the proposed MCLs.
Public notice and consumer reporting rules
Water systems would have to provide Consumer Confidence Reports and Tier 1 public notifications to customers when perchlorate levels exceed the MCL, with Tier 1 notification required for an exceedance because of the effect on the most sensitive population identified. These notices would inform customers about perchlorate detections and any required actions.
Personalized for You
How does this regulation affect your finances?
Personalize government policy and PRIA will tell you what this federal register document means for your household, plus every other regulation we track. PRIA reads each provision against your financial profile to show you exactly what matters to your wallet.
Key Dates
Department and Agencies
Related Federal Register Documents
2026-13667, Minor New Source Review Program Air Permitting Public Participation Requirements for State Implementation Plans
The EPA wants to give states more freedom to decide how much public input is needed when approving small air pollution sources or changes. This means local air agencies can tailor public participation to fit their community’s needs while still protecting air quality. If you’re involved in air permits, watch for comment deadlines and possible virtual hearings this summer!
2026-13263, Revisions To Establish the Sixth Unregulated Contaminant Monitoring Rule (UCMR 6) for Public Water Systems
The EPA is rolling out the sixth Unregulated Contaminant Monitoring Rule (UCMR 6) to check for new, sneaky chemicals in public drinking water. Big water systems serving 3,300+ people and some smaller ones will test for 30 different contaminants, including certain PFAS and pesticides, to keep our water safe. Comments and feedback are open until late August 2026, and the EPA will host fun online meetings to chat about the plan!
2026-12927, U.S. Ecology Nevada, Inc. High Mercury Subcategory Wastes Land Disposal Restrictions Variance
The EPA is giving U.S. Ecology Nevada a special green light to handle and dispose of high-mercury waste a bit differently than usual. This means mercury waste treated in Pennsylvania can now be safely sent to U.S. Ecology’s Nevada site for disposal under new rules starting July 27, 2026. This change helps protect people and the environment while keeping mercury waste management efficient and cost-effective.
2026-11047, National Emission Standards for Hazardous Air Pollutants From Hazardous Waste Combustors: Residual Risk and Technology Review
The EPA just updated rules for places that burn hazardous waste, like incinerators and boilers, to keep the air safe and clean. They confirmed current standards work well but added new limits on harmful gases like hydrogen fluoride and hydrogen cyanide. These changes start June 3, 2026, and include easier electronic reporting and some new rules for startup and shutdown times—helping protect health without big costs.
2026-10641, Hazardous and Solid Waste Management System: Disposal of Coal Combustion Residuals From Electric Utilities; Federal CCR Permit Program; Reopening of Comment Period
The EPA is reopening the comment period until June 29, 2026, for its proposed rule to create a federal permit program for safely disposing of coal ash from power plants. This affects electric utilities that handle coal waste and aims to improve environmental safety while possibly impacting their costs. Now’s the time for everyone to share their thoughts and help shape the rules!
2026-10387, Phasedown of Hydrofluorocarbons: Reconsideration of Certain Regulatory Requirements Promulgated Under the Technology Transitions Provisions of the American Innovation and Manufacturing Act of 2020
The EPA is updating rules to phase down hydrofluorocarbons (HFCs), chemicals used in cooling systems like refrigerators and air conditioners. These changes affect businesses in refrigeration, supermarkets, semiconductor manufacturing, and more, allowing some older equipment made before 2025 to keep running. The new rules kick in on July 27, 2026, helping industries transition smoothly while cutting harmful emissions.
Previous / Next Documents
Previous: 2025-24272, Restoring Flexibility in the Child Care and Development Fund (CCDF)
The government wants to make it easier and cheaper for states to run child care programs by rolling back some new rules from 2024. Families, child care providers, and states will see changes like no more strict limits on family co-pays and more flexible payment methods for providers. Comments on these changes are open until February 4, 2026, so everyone has a chance to weigh in before the new rules take effect.
Next: 2026-00048, Safety Zone; West of Cyril E. King Airport, St. Thomas, VI
The Coast Guard wants to create a permanent safety zone in the waters west of Cyril E. King Airport in St. Thomas, USVI, to keep boats and people safe from low-flying planes. This means no one can enter the zone without special permission. If you’re affected, you have until February 6, 2026, to share your thoughts—no fees or costs involved, just safety first!