Every state and every county in that state can have its own rules. For now just contact the same department and request a continuance due to the Corona virus. Just about every state agency I see or hear of is allowing that. If you are is any type of low area with a high water table you can just about bet you will fail a perk test. Most drain fields are in the 20 to 25 year range. 3 years ago we had a new drain field installed. We had enough room to keep the old drain field. They installed a diverter valve so if needed I could switch back to the old field. I was told that after 20 years the bacteria's eat up the sediments and they dry out so it could be used again. Cost was about 8 grand. I had a good concrete 1,000 gallon tank so it was allowed to be reused. If the tank was needed with all the codes met it would of been another 5 grand. Like I said every area is different with their respective codes.