Jump to main content or area navigation.

Contact Us

Water: Uniform National Discharge Standards (UNDS)

Batch Rulemaking Process

In 1996, Congress passed legislation amending the Clean Water Act to control discharges that are incidental to the normal operation of armed forces vessels. The legislation tasked EPA and the Department of Defense (DOD) to establish national standards. EPA and DOD have agreed to establish performance standards in batches. This is referred to as batch rulemaking.

How are EPA and the Department of Defense (DOD) identifying and evaluating discharges?

Phase I Identify and
Final Rule
Published on
May 10, 1999
Phase II Establish MPCD
Batch One
Phase III Develop
DOD Only Rule Completed One
Year After
Phase II


Top of page

Phase I

shipdischargessmOn May 10, 1999, EPA and DOD published the Phase I final rule in the Federal Register, 64 FR 25126; 40 CFR Part 1700. The Phase I rule identified all discharges incidental to the normal operation of armed forces vessels, and characterized each discharge to determine if it required control, based on its potential to have an environmental impact. The rule determined the types of vessel discharges that require control by a marine pollution control device (MPCD) and those that do not require control. EPA and DOD identified 39 discharges, 25 of which would require control by an MPCD.

The rule also established the mechanism by which states can petition EPA to review whether or not a discharge should require control, and the processes EPA and the states must follow to establish no discharge zones.

The rationale for the determinations of requiring control is documented in the Technical Development Document (TDD) for Phase I UNDS.

Top of page

Phase II

In Phase II, EPA and DOD, in consultation with the U.S. Coast Guard, are developing standards for each discharge that was determined to require control in Phase I. EPA and DOD have agreed to establish performance standards in batches, rather than promulgating standards for all 25 discharges at one time. This is referred to as batch rulemaking.

The batch rulemaking approach allows EPA and DOD to conduct technical analyses and develop discharge standards in two batches. A major advantage of this approach is that it speeds up the implementation of performance standards, thus more quickly realizing the goals of UNDS.  On February 3rd, 2014, EPA and DoD published proposed discharge performance standards for the eleven discharges in Batch One.  The proposed rule can be found at the Federal Register.

EPA and DOD must consider the following seven statutory factors in determining whether it is reasonable and practicable to require the use of an MPCD:

  • Nature of the Discharge
  • Environmental Effects of the Discharge
  • Practicability of using the MPCD
  • Effect of an MPCD on the operation of a vessel
  • Applicable United States law
  • Applicable international standards
  • Costs of MPCD installation and use
What discharges require Marine Pollution Control Devices?
Discharges NOT Requiring Control Discharges Requiring Control
During Phase I: the following discharges were identified and it was determined that they DO NOT require control. During Phase II: standards for these discharges will be developed in two batches.
Boiler Blowdown
Catapult Wet Accumulator Discharge
Cathodic Protection
Freshwater Layup
Mine Countermeasures Equipment Lubrication
Portable Damage Control
Drain Pump Wet Exhaust
Refrigeration and Air Conditioning Condensate
Rudder Bearing Lubrication
Steam Condensate
Stern Tube Seals and Underwater Bearing Lubrication
Submarine Acoustic Countermeasures Launcher Discharge
Submarine Emergency Diesel Engine Wet Exhaust
Submarine Outboard Equipment Grease and External Hydraulics
Phase II: Batch One
Aqueous Film-Forming Foam
Chain Locker Effluent
Distillation and Reverse Osmosis Brine
Elevator Pit Effluent
Gas Turbine Water Wash
Non-oily Machinery Wastewater
Photographic Laboratory Drains
Seawater Cooling Overboard Discharge
Seawater Piping Biofouling Prevention
Small Boat Engine Wet Exaust
Welldeck Discharge
Phase II: Batch Two
Catapult Water Brake Tank

& Post-Launch Retraction Exhaust
Clean Ballast
Compensated Fuel Ballast
Controllable Pitch Propeller Hydraulic Fluid
Deck Runoff
Dirty Ballast
Firemain Systems
Hull Coating Leachate
Motor Gasoline Compensating Discharge
Sonar Dome Discharge
Submarine Bilgewater
Surface Vessel Bilgewater/Oil-Water Separator
Underwater Ship Husbandry

Phase III
DOD will develop implementing instructions for vessels of the Armed Forces.
Top of page

Phase III

In Phase III, DOD, in consultation with EPA and the U.S. Coast Guard, will establish regulations governing the design, construction, installation, and use of MPCDs onboard armed forces vessels. These regulations will be required to meet the performance standards promulgated in Phase II. The Phase II performance standards do not become effective, nor does the preemption of state regulation of Armed Forces vessel discharges become effective, until Phase III standards have been promulagated.



Jump to main content.