The following interview was conducted on ABC Central West New South Wales radio with Janice McGilchrist on 17 September 2008 in her regular Making History Segment. Major Kevin Cuthbertson is the Australian Defence Force Manager of Explosive Ordnance Disposal with the Joint Logistics Command. He was the Commanding Officer of the Marrangaroo Military Base which has been the focus of a phosgene and mustard gas bomb find.

JANICE: Now you don't have to look too hard around Lithgow to find evidence of the area's involvement in the World War II effort; the small arms factory immediately comes to mind. But did you know about the munitions depot? Marangaroo was a major defence site, a serious munitions depot for Australia's armed forces involved in World War II through to the Korean and Vietnam conflicts. In Making History today, we take a closer look at the base, the myths and the realities. Manager of the site, Major Kevin Cuthbertson, good morning Major.

KEVIN: Good morning Janice, how are you?

JANICE: I'm well thank you. Firstly, can you take us back in time, when was the site established?

KEVIN: We go back to approximately 1942, Defence were establishing munitions locations to store, to manufacture and the importation of munitions required by the Australian Defence Force. They selected a variety of locations in isolated conditions, where there was not a lot of population around and Marangaroo was one of those selected at that time.

JANICE: Did it have also to do because it was close to rail infrastructure and that sort of thing?

KEVIN: One of the main reasons, you mentioned before the small arms factory, at that time, it's difficult to imagine now, but they were placed in locations where aircraft could not fly and attack those installations. If they did, their flight duration was pretty limited and consequently the further inland they could get, the safer the sites were considered.

JANICE: I see. I see. So the purpose was not only to manufacture but to store munitions. Are we looking at both explosive and chemical?

KEVIN: Well you've touched on the point that's of concern at the moment. Marangaroo did not manufacture, it was a storage location. It was close to, as you suggested before, the major arterial road going over the Blue Mountains, the heavy rail line that linked to Central and Northern Australia. It was used primarily because it bordered on the Newnes State Forest and it was built in against the plateau and it's like a hand, there were five fingers, that the valleys provided protection. You can understand explosive being stored, if one stack functions you need protection for the adjoining stack.

JANICE: I see.

KEVIN: So it fitted very well for the safety requirements at the time.

JANICE: So there was actually what, natural barriers between the stacks?

KEVIN: Yes you had spur lines that come down so the storage facilities in those days were asbestos sheeting built on a timber frame. But you would either build a revetment, an earth wall between each of the buildings, and the calculations were the quantity that could be stored in each site had a distance that if that potential site exploded it would not project over and function an adjoining stack.

JANICE: Okay and what was actually there?

KEVIN: All munitions, from small arms right through to howitzers, gun ammunition and Marangaroo was one of those camps that originally contained both army and RAAF personnel. So it stored general purpose bombs, 20 and 30 mil cannon, 50 calibre small arms ammunition. It was a broad range right across but bulk munitions mainly at Marangaroo.

JANICE: Okay and I'm led to believe that there was a lot of secrecy surrounding the munitions site, was that the case?

KEVIN:Yes it was. At that time the government decided, based on intelligence reports, that 1942, you're looking at the conflict over the Kokoda Track and they knew that the Japanese forces had chemical weapons. And at that stage the government decided that they would import, they tried to manufacture in Australia but to a limited degree, but they imported large quantities of mustard and phosgene gas from the UK primarily, but some from America. And most of these stocks ended up, or transited through Marangaroo.

JANICE: And that was to be kept secret?

KEVIN: It was classed as top secret. Its ramifications now we have started, there is a book that's been released this year by a Geoff Plunkett Chemical Warfare in Australia. All of the records were very sparse. It was treated as a top secret site. So the people that worked there - the RAAF armourers - they received very limited training. They were given a nine week course, but five days of that dealt with chemicals. And basically these guys they were sent to Marangaroo and from there forwarded onto places such as Glenbrook, just above Penrith, over at Picton and they established bases further north in Queensland and the Northern Territory.

JANICE: It's 21 to 11.00 you're listening to ABC Central West and we're speaking with Major Kevin Cuthbertson about the Marangaroo munitions depot. Major, was there any risk to the people that actually worked with this stuff at the time?

KEVIN: There's always risk with munitions. We have people today who their sole profession is the manufacture and the making of the explosive ordnances. So the risk is always there. But we're talking 60 years ago; the risks were far greater, the knowledge was less than we have now. The safety equipment and the occupational health and safety requirements were not quite as strict as we have today.

JANICE: So what has been, how active has the site been in the last few decades, is it still contributing to Australia's armed forces or?

KEVIN: It does but it's no longer used as a storage location. Going back to 1992, '93 the bulk and the last of the serviceable stock was removed and transferred to other depots, the main one being in the Hunter Valley.

JANICE: Okay so what's happening now? I understand that the Defence Department is moving to clean up the site now, what's happening?

KEVIN: Yes the depot itself is still being used by tri service; army, navy and airforce. It has two internal demolition ranges and you understand that the requirements to safely function explosive is still pretty much high on the agenda for defence. They use the ranges, the basic schools from the clearance divers, school of military engineering, the army ammunition technicians course, the RAAF explosive ordnance disposal flights, they frequently go to Marangaroo still to this day, and conduct the basic training where they teach their technicians how to recognise, neutralise and destroy munitions that we currently work with. But it's also used as a site to dispose of military ordnance still being found resulting from World War II.

JANICE: And you're an explosive disposal expert, is that right?

KEVIN: Ammunition technician.

JANICE: Ammunition technician.

KEVIN: An expert I will challenge. If you ever claim to be an expert, then there is always something new that you don't know.

JANICE: Well that's what I was going to get to. I would imagine that technology in inverted commas has changed considerably over the years and you've probably witnessed that?

KEVIN: Yes the types of explosive, the methods of initiation, we now have binary explosive that being a two part composition, until the two components are actually mixed it's an inert substance.

JANICE: In terms of this clean up, I guess why wait until now 2008 before the site is cleaned up and either turned over to public hands or people move on?

KEVIN: No Janice, I'll challenge that statement. Defence are not cleaning up the site to hand it over.

JANICE: What's happening then?

KEVIN: This is a valuable training site in close proximity to Sydney. So as a training location, it is very valuable to the continuation of training our explosive technicians. The site itself, we've progressively identified and established locations, and go back 60 years, you've got the Japanese coming through New Guinea, the talk of the Brisbane Line was very strong on everyone's lips -the possible invasion of Australia. The methods of disposing of unsafe or unstable explosive munitions was not what we know of today, basically they would look for erosion, excavation or holes in the ground and literally the items were just dumped in the ground, buried and we'll deal with that later, the problem is the invasion. So we've now looked at and have established a number of areas throughout Australia and the Defence Support Group are sitting back now and starting to establish where those locations are and clean up is taking place. Marangaroo has been identified primarily because the burial and disposal of chemical containers - it was substantiated only recently where some of these containers, and that is only as recent as 2003. And we've started to establish a explosive ordnance disposal team who are now identifying each of the locations within an area of Marangaroo and through Defence, we are now cleaning up and getting those chemical items out of the ground.

JANICE: Okay so now we have the technology to do it properly, whereas before we may not have been able to do the - dispose of these things adequately?

KEVIN: Janice talking with some of the survivors that are still alive from the chemical armourers, their method of disposal was to, one was to dig a pit, line it with timber, pour diesel over it, place the drums in the middle, set fire to it and then fire small arms through the container.

JANICE: Wow.

KEVIN: It was burnt. Phosgene, they would simply stand the canister up in the open air, wait for the wind to blow in the opposite direction and shoot bullet holes through the containers. So yes, technology has changed.

JANICE: Has moved on. Is there any risk, and I suppose is there any risk to locals in the process of this clean up?

KEVIN: We had a meeting with the locals a fortnight ago and DSG have gone through and they have conducted door knocks and spoken with the majority of the residents at Marangaroo, living on the approach road. Defence have taken extraordinary steps to maintain and make sure that there is no chemical, if it is accidentally released, that it will escape off the Commonwealth property boundaries. So the residents, we've been taken over the site. Equipment has been put in place that should there be an accidental release, it can be contained and dealt with onsite. But again, occupational health requirements for our workers that are on site, and to be able to negate these chemicals, should they be released, it will make sure that the residents are 100 per cent safe.

JANICE: And Major when do you imagine this whole exercise will be complete?

KEVIN: We have a DUXOP company, that's a defence unexploded ordnance contracted company who are tasked with the cleanup. They are already onsite, but through training and further equipment to be bought in, the actual physical removal of the remaining chemical containers will be in January of next year.

JANICE: Okay, interesting story. Thank you for explaining it to us.

KEVIN: You're welcome.

JANICE: Major Kevin Cuthbertson there has been looking after the munitions depot at Marangaroo.