36 CFR §14.6

1. (a)An applicant may withdraw an application at any time during the permitting process.
2. (b)If at any time during the permitting process an applicant does not respond to a written communication from the NPS within 90 days, the NPS may presume that the application has been withdrawn without further notice to the applicant.
3. (c)When an application is withdrawn or presumed withdrawn, the permitting process is terminated and the applicant must resubmit a new application pursuant to § 14.4 of this part.