Uniform State Plumbing Code shall:

(a) Inspect its grease traps and interceptors at least monthly; and (b) Have its grease traps and interceptors cleaned, with their contents hauled for disposal, whenever the level of grease is at least 25% of the effective depth of the trap, or at least every three months, whichever is sooner. (8) Required Notices to the Authority. In addition to the notices otherwise required by 360 CMR 10.000, a Person with the General Permit must notify the Authority in writing at least 30 days before it closes or moves a facility covered by the General Permit, changes its facility's operations such that the discharge will change so that the facility may no longer be eligible for the General Permit, or makes any other substantial change in the volume or character of its facility's discharge. (9) Change in Volume or Character of Discharge. If a change in the volume or character of a facility's discharge will make it ineligible for coverage by the General Permit, the Person must obtain the applicable Authority permit for the facility before beginning the changed discharge. The Authority may require a Person to complete and file a Permit Application or NOI if it has reason to believe that the Person’s facility may no longer be eligible for the General Permit or the Person has made substantial changes to its facility since receiving the General Permit. (10) Record Keeping Requirements. A Person with the General Permit for a facility must keep for at least five years all hazardous waste manifests and records of any Photo Processing and Printing wastes and grease trap wastes it had hauled from its facility and make a copy of the documents available to the Authority upon request.