(1) If an analyst has identified a seized substance as being or containing a drug of dependence, prohibited substance or chapter 6 substance, the government analyst shall dispose of any remaining quantity of the substance—
(a) if, within 3 months of the seizure, proceedings are instituted for an offence in relation to the substance—after those proceedings are completed; or
(b) in any other case—at the end of 3 months after the date of the seizure.
(2) However, the government analyst need not dispose of a substance when required to under subsection (1) if the analyst—
(a) tells the chief health officer in writing that the analyst intends to use the substance as a reference under the Public Health Act 1997
, section 15AA (Analysts and assistants—authority to handle drugs etc); and
(b) removes from the substance any information that links the substance to an offence or prosecution or to a person from whom it was seized.