| #R001 | operational | operational | mandatory | Application of Technology-Based Standards | wastewater | These technology-based standards apply regardless of whether or not the publicly owned treatment works (POTW) has an approved pretreatment program or whether or not the nondomestic discharger has been issued a control mechanism or permit. | Applies to nondomestic dischargers regardless of POTW program status or control mechanism issuance. | high |
| #R002 | operational | operational | mandatory | Applicability of Pretreatment Standards | wastewater | Pretreatment standards are pollutant discharge limits which apply to industrial users (IUs). | | high |
| #R003 | operational | operational | mandatory | Applicability of Pretreatment Requirements | wastewater | Pretreatment requirements are substantive or procedural requirements applied to IUs. | | high |
| #R004 | administrative | operational | mandatory | NPDES Permit Compliance | wastewater | NPDES permits establish discharge limits and conditions for discharges from municipal wastewater treatment facilities to waters of the United States. | Applies to discharges from municipal wastewater treatment facilities to waters of the United States. | high |
| #R005 | operational | operational | recommended | Maximization of Wet Weather Flows | wastewater | The CSO policy encourages municipalities with combined sewers to maximize wet weather flows to the treatment plant in order to decrease uncontrolled overflows in the collection system. | Applies to municipalities with combined sewer systems during wet weather conditions. | high |
| #R006 | administrative | reporting | guidance | Integrated Planning Participation | wastewater, other | integrated planning offers a voluntary opportunity for a municipality to propose to meet multiple CWA requirements by identifying efficiencies from separate wastewater and stormwater programs and sequencing investments. | Voluntary opportunity for municipalities to coordinate wastewater and stormwater programs. | high |
| #R007 | prohibition | operational | mandatory | Combined Sewer Construction Restriction | wastewater | State and local authorities generally have not allowed the construction of new combined sewers since the first half of the 20th century. | Applies to the construction of new sewer systems. | high |
| #R008 | treatment | treatment | mandatory | Secondary Treatment Standards Compliance | wastewater | Secondary Treatment Standards - Minimum, technology-based standards for discharges from municipal wastewater treatment facilities. | Minimum technology-based standards for municipal wastewater discharges. | high |
| #R009 | administrative | operational | mandatory | National Pretreatment Program Applicability | wastewater | The national pretreatment program identifies specific discharge standards and requirements that apply to sources of nondomestic wastewater discharged to a POTW. | Applies to sources of nondomestic wastewater discharged to a Publicly Owned Treatment Works (POTW). | high |