Mining commenced in the Medway area, on the banks of the Medway Rivulet, in 1867 at the Cataract Mine. This closed in the early 1870’s, re-opened in 1874 and the closed again in the late 1870’s. 

Another company was formed in 1881 to mine coal on the Medway Rivulet and a private rail line was built to the main southern line at Moss Vale. This company was short lived being liquidated in 1886.

In 1923 W.E. Marsh opened the Loch Catherine Colliery, south of the existing Berrima Colliery.  Again the Wongawilli seam was mined. A third mine known locally as the Flying Fox Mine was also established on the Medway Rivulet near Loch Catherine. Men and materials entry was via a flying fox over the Medway Rivulet. Some foundations of the Loch Catherine winder house and the steam drive traction engine still exist at the Loch Catherine site approximately one kilometre south west of Medway Village. 

In 1924 the Medway Colliery and Railway Company was formed to mine coal at the site of the existing Berrima Colliery. A rail spur from Medway to Moss Vale was constructed and in 1926 the Medway township was developed. 

In 1926 the Southern Portland Cement and Coal Company was formed to construct a cement works south of Berrima. The Medway Colliery and Railway Company was taken over and became the source of Kiln fuel for the Cement Works. 

Similarly the adjacent Loch Catherine Colliery was used as a source of Kiln for the Malden Cement Works. When an alternative source of supply for the Malden works was found in 1959 the Loch Catherine Mine was closed. 

The Berrima Mine was mechanised in 1968 with the introduction of a continuous miner and shuttle cars and since that time production from the mine has normally varied between 200,000 and 260,000 tonnes per annum. The annual output of the mine has occasionally been boosted by spot sales on the domestic market but they have  generally been of minor significance. The only major sale has been 80,000 tonnes to Tallawarra Power Station in 1981 when annual production reached 330,000 tonnes. To counteract that, production was only 125,000 tonnes in 1983 when there was a severe downturn in the building and construction industries. 

Blue Circle Southern was formed as an amalgamation of several Australian cement companies (including Southern Portland Cement) in 1974 as a joint venture between BHP and Blue Circle, UK. In 1988 Blue Circle Southern was sold to Boral. 

Centennial Coal Company purchased the mine from Boral/Blue Circle Southern Cement in June 1994. 

Berrima Colliery is in the south – western part of the Sydney Basin Coal Region.

The Illawarra Coal Measures contain only two seams in this area, the Wongawilli and the generally thin Tongarra (or American Creek).

Overlying these coal measures are some 110 metres of Hawkesbury Sandstones with Wiannamatta Shale making up the surface (depending upon the level of erosion). 

The Wongawilli seam is approximately 10 metres in thickness (including coals and carbonaceous shales) but only the basal 2 – 3 metres are economically mineable. 

The limited cover (100-150 metres) causes little stress at the working face. As such the mining conditions are exceptionally good, with a minimum of roof support required to work the mine safely.

NSW mines are usually subject to faults, elevated stresses, gas, rolls and igneous intrusions. The only problems experienced by Berrima Colliery are igneous intrusions in the form of dykes and volcanic plugs. 

The dykes vary in thickness from 0.2 – 10 metres at seam level but are usually altered and relatively soft. Penetrating the cindered zone on each side of the dyke presents the main challenge, as well as the support of the roof and ribs within the dyke areas. 

Wet weather can result in large volumes of water flowing down the dykes with additional pumping facilities sometimes required. 

Volcanic plugs, resulting from extinct volcanoes, have destroyed sizeable volumes of coal within the leasehold  and mine planning needs to be mindful of their locations. 

The mine currently has around 22 employees, producing an average of 200,000 tonnes (at 32% ash) per annum for use in the nearby Berrima Cement Works. Beneficiation consists only of crushing the + 50 mm fraction.

Based upon information supplied by Berrima Colliery, 2001.