the confidentiality of personal information. 1993, c. 5, s. 29 . Disclosure by Public Archives 30 The Public Archives of Nova Scotia, or the archives of a public body, may disclose personal information for archival or historical purposes where (a) the disclosure would not be an unreasonable invasion of personal privacy pursuant to Section 20; (b) the disclosure is for historical research and is in accordance with Section 29; (c) the information is about someone who has been dead for twenty or more years; or (d) the information is in a record that is in the custody or control of the archives and open for historical research on the coming into force of this Act. 1993, c. 5, s. 30 . Disclosure in public interest 31 (1) Whether or not a request for access is made, the head of a public body may disclose to the public, to an affected group of people or to an applicant information (a) about a risk of significant harm to the environment or to the health or safety of the public or a group of people; or (b) the disclosure of which is, for any other reason, clearly in the public interest. (2) Before disclosing information pursuant to subsection (1), the head of a public body shall, if practicable, notify any third party to whom the information relates. (3) Where it is not practicable to comply with subsection (2), the head of the public body shall mail a notice of disclosure in the prescribed