Conrad Mine

Although previous rehabilitation has been undertaken the site remains one of the highest risk sites on the Derelict Mines Program database due to offsite environmental impacts.

Derelict Mines Program (DMP) has previously completed works at the site capping the upper tailings and improving drainage, however as part of the continual risk assessment and mitigation under the Program further works will be completed at site during 2017. The 2017 works will consolidate mine wastes from around the site and encapsulate these at the lower tailings area.

Current Site Description

The site is currently highly disturbed and there are numerous significant historical features remaining at site such as the Conrad Shaft, rock stack at location of the King Conrad Shaft (pictured below) and numerous footings and other remnants from processing and concentrating infrastructure.

Rehabilitation Works

The Legacy Mines Program has managed site investigations and rehabilitation and safety works at the site since the year 2000.
Rehabilitation works to date include:

• Capping, containment and seeding of the upper tailings dump (pictured right), to prevent erosion of heavy metal-contaminated materials and to prevent contaminated leachate seepage.
• Capping, containment and seeding of the lower tailings dump via installation of gabion basket retaining structures and installation of clean water diversion channels to prevent erosion of heavy metal contaminated materials directly into Borah Creek.
• Consolidation and capping of waste rock piles adjacent to Conrad and King Conrad shafts
• Water diversion structures and creek bank stability works around the Conrad shaft and upper Borah Creek areas to prevent erosion of heavy metal contaminated materials and leachate production.
• Protection of heritage relics and cultural aspects of the site.
• Fencing of the Conrad main shaft with bat friendly grate.
• Re-capping and fencing of the King Conrad shaft.
• Installation of drainage structures, filter bunds and sediment retention dams to slow material moving off site.

Mine History and Heritage Value

Conrad Mine was sporadically operated between 1898 and 1957 under various names and operators.

The Conrad shaft was the first operational shaft, followed by the King Conrad shaft in 1900.  Later smaller shafts were added, such as the Moore and Allwell shafts.

The Conrad mine ceased activities on 27 December 1957 due to low metal prices, poor grade ore and high cost of production. The plant and equipment were dismantled in 1958-1959.

A small amount of ore was obtained from the Allwell dumps in 1966 (the ore in the Allwell shaft was hand-picked with no machinery involved in the operations). Occasional exploration works have been conducted on site since the closing.

During the operations approximately 177,800 t of ore was raised, which produced approximately 17,800 t of concentrate, consisting mainly of silver-lead, copper and arsenic.

The mining activities consisted of tunnelling on the lode for long distances underground, with tunnels connecting different areas of operations, such as the King Conrad, Conrad and Moore shafts. The deepest shafts extend approximately 270 m Below Ground Level (BGL). The ore was concentrated on site and the resulting mainly silver-lead and copper-tin rich concentrates smelted and transported from the site.

It was noted in 1922 that the waters occurring in the mines contain high concentrations of arsenic and should be handled carefully. The significant environmental impacts caused by the site were recognised in the late 1970’s. In 1980 some of the old shafts and collapsed stopes at the site were permanently covered for safety reasons.

According to Burke (2000) the site has moderate heritage value relating to European mining history and artifacts, and some value for scientific, educational and tourism activities. Therefore preserving these values is an important component of any proposed further remediation/rehabilitation works at the site.