Alternate operating scenario (AOS) for engines

To report an engine replacement (if authorized by your permit)

First, complete an Applicability Report for your replacement engine. 

• The Applicability Report is your explanation of the regulatory requirements that apply to the replacement engine

Next, submit the Applicability Report with a revised APEN:

• Natural gas engines.
• Diesel engines.

Additional guidance:

• PS Memo 98-06
  Permit conditions for natural gas-fired engine AOS.
• PS Memo 11-04
  Permit conditions for diesel engine AOS.
• PS Memo 11-05
  Adoption of AOS for natural gas-fired engine permits not containing an AOS provision.