The purpose of this rulemaking is to require use of a new Environmental Resource Permit (ERP) Modification Short Form application form instead of a letter when permittees apply for certain minor modifications of ERPs, and to allow applications to extend the duration of an ERP to be made using this new form. Modifications allowable through use of the Modification Short Form do not require an application fee. Rule amendments also eliminate the requirement to determine that completed construction complies with a currently valid permit when a permittee applies to extend the duration of a permit. Amendments also replace the term "renewal" with the term "extension." The effect of these amendments will be to standardize the process for seeking minor modifications of ERPs.