The Board shall not permit the manufacture, possession, use, distribution, or dispensing of any controlled substance, alcohol, and any drug paraphernalia as the term is defined by law, by any member of the District''s professional staff at any time while on District property or while involved in any District-related activity or event. Note: During a prolonged absence as defined by board policy, the substitute is responsible for performing all essential functions identified in the absent teacher''s job description.