Laws & Regulations

EPA responds to State and Tribal Recommendations for the 2015 Ozone Standards

2015 Ozone NAAQS,

Learn About Nitrogen Dioxide Designations

Basic information about Nitrogen Dioxide Designations

Lead Designations - Kansas State Recommendations and EPA Responses

Lead Designations - 2008 Standards. Kansas State Recommendations and EPA Responses, Round 1 and 2

2015 Ozone Standards - EPA Intended Area Designations for Other Tribes

EPA letters to tribes impacted by designations for the 2015 ozone standards

Commonwealth of the Northern Mariana Islands National Pollutant Discharge Elimination System (NPDES) Permits

NPDES water permits pending and issued in the Pacific Island territory of the Commonwealth of Northern Mariana Islands (CNMI).

Nevada National Pollutant Discharge Elimination System (NPDES) Permits

In Nevada, EPA’s Pacific Southwest (Region 9) issues all NPDES permits for any discharges on tribal lands. All other NPDES permits are issued by the Nevada Division of Environmental Protection (NDEP).

Hawai'i National Pollutant Discharge Elimination System (NPDES) Permits

EPA's Pacific Southwest (Region 9) issues all NPDES permits for any discharges into federal ocean waters in Hawai'i. All other NPDES permits are issued by the Hawai'i Department of Health.

California (Non-Tribal) National Pollutant Discharge Elimination System (NPDES) Permits

EPA’s Pacific Southwest (Region 9) issues NPDES permits for any discharges into federal ocean waters. All other permits are issued by the California Environmental Protection Agency (CalEPA).

California Tribal Lands National Pollutant Discharge Elimination System (NPDES) Permits

EPA’s Pacific Southwest (Region 9) issues all NPDES permits on tribal lands in California and for any discharges into federal ocean waters (for these permits, see: California NPDES Permits).

Guam National Pollutant Discharge Elimination System (NPDES) Permits

NPDES water permits issued in the Pacific Island territory of Guam.

Navajo Nation National Pollutant Discharge Elimination System (NPDES) Permits

EPA’s Pacific Southwest (Region 9) issues all NPDES permits on Navajo Nation tribal lands.

Arizona Tribal Lands National Pollutant Discharge Elimination System (NPDES) Permits (Excluding Navajo Nation)

In Arizona, EPA's Pacific Southwest (Region 9) issues all NPDES permits for discharges on tribal lands. All other permits are issued by the Arizona Department of Environmental Quality.

Frequent Questions about e-Manifest

Frequently Asked Questions (FAQ) about e-Manifest covering these areas: scope, generators, receivers, manifest preparation & brokers, federal and state implementation, fee obligations, record retention, data policy, data correction, and user registration.

Texas SIP Background Information

Water Quality Certification of the Quillayute River Oxbow Restoration on the Quileute Reservation

Public notice of EPA's proposed water quality certification of the Historic Oxbow Restoration and Steep Hill Road Rehab and Re-Route Project on the Quileute Reservation in Washington.

Comments Due Date: February 13, 2026
Geographic Locations: Washington, Pacific Northwest, Tribal Lands