It is unknown where the adit leads; however it does go west towards the nominated site and possibly is linked with the known vertical shafts (asylum shafts). The adit drains water from the mine by gravity, it would appear from the outside that the adit has minimal obstructions and often has water draining from it. The site has archaeological potential for finding information relating to colonial mining techniques. The front of the original building was demolished in the mid 1800s for the realignment of Church Street; however a significant portion of the parsonage was retained when additions were made to Reception House by Architect Walter Vernon. The parsonage (recently Kirkwood House/Reception House) was demolished in 2008 and an archeological excavation took place in March 2009. Remains of the old parsonage (1819) were found, including sections of wall, a cellar and other relics as evidence of the convict period. The size of the remains (foundations) is approximately 12x10 metres. The convict brickwork (floor/foundations) was in excellent condition (for its age), and represents building methods and techniques used in the convict era. The hospital is a walled site within an excavated quarry. The wall has enclosed the buildings on the site since the military buildings were first constructed in 1842. With exception of the northern boundary, the south, east and west sides all have walls. Originally built as a retaining wall for the excavated site, then it was later retained for privacy for patients of the mental institution. The integrity of the compound wall is better in some sections than others. Sections of the compound wall were damaged in the June 2007 floods. The foundation of the inside wall appears to be built from sandstone. The wall runs from north to south and is relatively intact. However much of the upper sections of the wall built from brick have collapsed and are in need of repair. The walls were constructed from brickwork dated at different periods, and the significant sections of the stone wall in the lower sections of the compound wall may relate to the 1830s when the site was quarried using convict labour. There is high archaeological potential, given that the site was "prepared" for construction of the barracks using convict labour. The landscape of the current hospital grounds shows an exposed quarried landform on the south side, approximately 20 metres high. The exposed rock has eroded somewhat due to environmental conditions; however this landscape remains a noticeable and strong feature of the site, the quarried section that formed a wall runs the full length of the southern boundary.