R. L. Newbould

The Jenolan Caves have six sections of its interlinking system of intricate passageways and chambers on show to the general public in the southern section of the limestone off the Grand Arch.

Lucas Cave is the largest section of these show caves. It has been shown to the public for over 100 years and caters for approximately 50% of the total number of visitors who inspect the caves each year at Jenolan.

Orient Cave is another branch that was found in 1904, and connected by what we all know as the River Cave and this in turn is connected to the Lucas Cave.

The natural air flow in these caves would be governed by the climatic conditions outside. A tremendous air-venting system would be in operation in these caves.

The show caves have experienced many developments and improvements since they were first discovered. By the early 1950s visitation in the caves had increased to over eighty thousand (80,000) persons annually.

This meant on volume of visitation alone, each year, Lucas Cave was becoming more discoloured by mud and dust from the visitors footwear that was accumulating alongside the steps and tracks. The abrasive action of the people's clothing chafing against other persons and against the fence work dispersed animal and vegetable fibres into the air.

In 1954 the Binoomea Cut was implemented. This man-made tunnel was completed to give improved conditions to the general public who would be visiting the Temple of Baal, Orient and Ribbon Caves. No doubt the natural airflow was upset by doing this and the combined group of show caves soon became more discoloured.

Early in 1961, it was apparent that the caves needed some sort of a cleanup of the decorations. It was decided that steam cleaning could be the answer to the problem.

The Orient Cave was selected for the experiments that would be carried out, owing to easy access if any heavy or awkward equipment was needed, also the cave would have to be closed to visitors.

During May 1961, a fuel-operated steam unit was experimented with in the Orient Cave. This proved to be unsuccessful because of the heavy soot deposits.

In June 1961, undiluted detergent was sprayed on to the cave decorations. Scrubbing brushes were used and finally hosing down with clean water. This method of cleaning a cave was out of the question and Mr Harman, the senior guide pressed for the introduction of a steam unit electrically operated.

In April 1962, experiments with a Clayton portable steam generator was carried out. This was unsuccessful due to the length of steam line required to pump steam into the caves for cleaning. Sufficient steam pressure could not be generated by this method.

During December 1963, further tests were carried out in the Orient Cave, with the intention of using a Fradic steam cleaner, comprising a solution unit, control unit and generator and all hoses between the units. The tests did not prove to be satisfactory.

During June 1964, the Department of Public Works was informed of the cleaning problems at Jenolan Caves and of the exhaustive tests by private enterprise. The Department of Public Works informed the Department of Tourism of a firm in Sydney who manufacture and distribute steam generators.

On the information supplied by this particular firm in Sydney a number of visits were made by the resident engineer, Mr Stein and the senior guide, Mr Harman, to inspect steam units in operation. On their visit during October 1965, certain requests for modifications to one of the steam boiler units were put forward and eventually accepted. This modified steam boiler unit was then recommended by Mr Harman and Mr Stein for purchase by the Department of Tourism. The specially modified steam boiler unit was collected in June, 1966.

Many delays in obtaining special electrical equipment hampered the steam cleaning work being effected as planned.

The Orient Cave was closed to the public on March 14, 1968. On March 15, all the equipment was carried into the Orient Cave for its assembly. The programme of steam cleaning with detergent began and continued through with various delays until completion on September 30, 1972.

Two, one thousand wattage quartz-iodine lamps were used to penetrate the heavy fog that existed in the cave. One climbing pole and special wire rope ladders were used as an aid to gain access to the awkward and higher sections of the Orient Cave.

No more than twenty (20) gallons of detergent was used for the whole of the steam cleaning project that took a period of four and one half years to carry out. The higher banks and ledges in the Orient Cave were the dirtiest. The complete area of the Orient Cave was steamed clean and finally washed with clean water.

The final results could be said to be highly successful and the guiding staff of Jenolan Caves are very proud of the great achievement made in this field of restoration of a cave from pollution.

The Orient Cave was put back on show to the public on October 1, 1972. After one month of public visitation, 1,476 persons had viewed the Orient Cave. On examination of the cave, it was noted that fibre particles were clearly visible on the wire netting fence work. Mud and grit had been walked along the length of the cave track.

A final examination of the Orient Cave was made on April 1, 1973. For the six months period, 8,222 persons had visited the cave. An amazing amount of textile fibres was adhering to the wire netting fence work. Mud and grit are covering the track and steps. In areas some mud has been deposited on areas of flowstone beside the track.

It is hoped that the method of steam cleaning with detergent will be applied to the other existing caves that are on display to the public at Jenolan Caves.

(Mr Newbould has also provided a more detailed account of this work in Occasional Paper No.1 of the Jenolan Caves Historical and Preservation Society.)