Over a week into the industrialised despatch of 120,000 sheep, the Great Orton airfield converted to a mass animal grave emits an overpowering smell.

Whether it is the sheep carcasses or the 20 truckloads of slaughtered cattle is hard to say.

One thing is certain - the routine of burying the sheep and slaughtering and burying the ones that arrive live at the Cumbrian site has become a grimly efficient operation.

It is like a livestock market or abattoir working at maximum pitch

Lieutenant Colonel Angus Tavener

Slaughtermen and vets working in teams of four, 120,000 carcasses buried in just over a week, it is a dawn-until-dusk day for everyone.

"It is like a livestock market or abattoir working at maximum pitch", said Lieutenant Colonel Angus Tavener, one of the Army commanders attached to the disease control team.

Behind him as he stood at the perimeter of the old airfield could be seen the trucks which arrived 24 hours earlier carrying slaughtered cattle.

They should have been buried by now but the directive from Agriculture Secretary Nick Brown two days ago had been challenged by the Department of Health.

Was it safe to bury animals which might be carrying the BSE virus?

Questions and uncertainty

Yes, said the Ministry of Agriculture, citing scientific advice, as long as the cows were less than five years old.

But how could you determine the exact age of every beast being rushed through in a massive emergency operation?

The questions went on, meetings were held in Whitehall, then Nick Brown arrived for his own meeting in Carlisle and told reporters "burial will go ahead".

The doubts or objections had evidently been answered.

Mark Shadwick, a Cumbrian farmer who lost all his own stock to foot-and-mouth, said: "Whichever option you take, there is some drawback or risk".

Whichever option you take, there is some drawback or risk

Mark Shadwick Cumbrian farmer

But after the 1967 outbreak, a report clearly recommended burial as a sensible policy.

Then, of course, we had not heard of mad cow disease.

Among the Army personnel supervising the mass cull, there is growing optimism that they are starting to get on top of the epidemic.

Brigadier Alex Birtwistle, the officer leading the Army team, said they were beginning to reduce response times, from discovery to slaughter, down to hours rather than days.

Next big challenge

The task of collecting and delivering condemned livestock has been down to the 182 trucks shuffling around the county

The Army believe that by Thursday or Friday the backlog of animals originally earmarked in exclusion zones will have been disposed of.

Then everyone comes face to face with the next big challenge - setting and enforcing firebreaks around new infections in Cumbria.