36 CFR § 9.73 - If I don't need an operations permit, are there still requirements that I must meet?
If the NPS notifies you under § 9.72 that you do not need an operations permit, your operations are still subject to the general terms and conditions in §§ 9.120 through 9.122, the prohibitions and penalties in §§ 9.180 through 9.182, and the requirements in this section.
(a) You must notify the NPS within 30 days if the methods or the environmental conditions of your downhole operations materially change.
(b) The Regional Director may notify you in writing that you are no longer exempt from the operations permit requirement after determining that downhole operational requirements are needed to protect against a significant threat of damage to any of the following:
(1) Federally owned or administered lands, waters, or resources of System units;
(2) NPS visitor uses or experiences; or
(3) Visitor or employee health or safety.