Learn the Issues

Map of Watershed Plans in the San Juan Watershed

Interactive map of watershed plans in the San Juan Watershed.

Grants for State and Interstate Agencies under Section 106 of the Clean Water Act

Each state and territory has established programs to protect and restore fresh waters, coastal waters and wetlands as outlined in the Clean Water Act. Section 106 grants support the implementation of those programs.

NPDES Stormwater Webcasts

Webcasts and webinars for NPDES stormwater.

Stormwater Discharges from Transportation Sources-Research, Tools, and Webcasts

Transportation authorities manage the runoff on street, road, and highways that has polluted by cars, trucks, buses, and other vehicles.

Stormwater Discharges from Municipal Sources-Developing an MS4 Program

Polluted stormwater runoff is commonly transported through municipal separate storm sewer systems (MS4s), and then often discharged, untreated, into local water bodies.

Map of Water Quality Assessment Results of the San Juan Watershed

Interactive map with information on the condition of the San Juan Watershed including outcomes of state assessments of water quality under the Clean Water Act.

Monitoring Data and Map in the San Juan Watershed

Map and data links of monitoring along the San Juan River.

How will the term "tolerances" be interpreted as a practical matter by EPA as it relates to specifications? As a clarification, please respond to the following: An importer who elects to comply on a "per-gallon" (vs. averaging) basis must meet an RVP maximum specification of 8.1 during the summer months. The EPA has established a 0.30 psi tolerance for this test. Consider the hypothetical, but likely situation whereby such an importer brings a cargo of RFG into New York Harbor which was determined by an independent inspector abroad to contain 8.1 psi at load. Upon discharge at New York Harbor by another independent inspector, the cargo was found to contain 8.3 psi. This second inspector's results are later confirmed by the EPA. Is this importer in compliance, due to the fact that the product conforms, within the established tolerances to the specifications established by EPA? Does the loadport analysis have any
bearing on this matter? In the event the importer is found to be out of compliance, would he be subject to penalties under the Act? If so, would the loadport inspection certificate be construed as a satisfactory defense against an enforcement proceeding?

See More Frequent Questions about Fuels Registration, Reporting, and Compliance Help . As stated in the Preamble to the Final Rule, 59 Fed. Reg. 7764, "refiners and importers may not use the tolerance to expand the applicable standard. Further, product must meet all applicable specifications when it leaves the refinery…

Last published: May 29, 2025

How will RFG impact ASTM motor fuel specifications?

See More Frequent Questions about Fuels Registration, Reporting, and Compliance Help . Fuel marketed in RFG areas must comply with the RFG regulations. If ASTM standards conflict with the RFG regulations, The ASTM standards will, in effect, be superseded. (7/1/94) This question and answer was posted at

Last published: May 29, 2025

I am an ethanol marketer and importer, and, although I am not certain, I may import gasoline before the end of the compliance year. Can I separate RINs from the ethanol that I purchase and import?

See More Frequent Questions about Fuels Registration, Reporting, and Compliance Help . In general, we believe that most RFS program participants will know at the beginning of the compliance year the nature of their business activities for the upcoming compliance period, and therefore will not need to worry about the…

Last published: May 29, 2025

How will EPA enforce their regulations in California? Will the Agency defer to the California Air Resources Board?

See More Frequent Questions about Fuels Registration, Reporting, and Compliance Help . Prior to the start of the California Phase II RFG program in March 1996, EPA generally will enforce the federal RFG program California in the same manner in which it will be enforced in other parts of the…

Last published: May 29, 2025

Smart Sewers

NPDES CSO policy memoranda, reports to Congress, and trainings.

How will EDI agreements affect third parties?

See More Frequent Questions about Fuels Registration, Reporting, and Compliance Help . An EDI agreement will be binding only on the Agency and the cosigner of the agreement. (7/1/94) This question and answer was posted at

Last published: May 29, 2025

Stormwater Discharges from Municipal Sources-Resources

Polluted stormwater runoff is commonly transported through municipal separate storm sewer systems (MS4s), and then often discharged, untreated, into local water bodies.

Resources, Tools and Databases about Impaired Waters and TMDLs

A collection of impaired waters and TMDLs resources for both the general public and water resource managers.

CWA-09-2025-0005: Consent Agreement and (Proposed) Final Order; CEMEX Construction Materials Pacific LLC, Wadsworth, Nevada

Proposed administrative penalty settlement with CEMEX Construction Materials, Pacific, LLC, for violations of the Clean Water Act at its facility in Wadsworth, Nevada. EPA Docket No. CWA-09-2025-0005.