Accessory structure allowed. A principal use and structure may also have one accessory structure, provided such accessory structure is secondary to the principal use and structure and is commonly considered to be associated with the principal use. Notwithstanding the above, a principal use may also separately have one pool. In addition, such principal use and structure may also have additional accessory structure(s) only upon the issuance of a special use permit by the Zoning Board of Appeals, as provided in § 165-114 of this chapter (and, where applicable, site plan approval from the Planning Board).