The Environment Agency has intervened to prevent an appalling smell at Yeadon which has forced residents to keep their doors and windows shut.
The stink, described as "dreadful" , was so bad that washing could not be hung out and some people were reluctant to let their children play out.
Now the Environment Agency is working with the company responsible to get the problem under control.
A spokesperson for the Environment Agency said: "The Environment Agency has investigated landspreading activities at Yeadon following reports of excessive odour in April and May this year. We have visited the area and looked into the activities of a company that has an environmental permit for land spreading there.
"Our officers have found no evidence of illegal practices being carried out, but in response to the reports of excessive odours we have been working with the company to ensure that the risks are minimised. An odour management plan has been submitted by the operator so the waste will be injected into the soil or ploughed into the soil within 24 hours if it is spread on top. The company has for the time being stopped spreading the type of waste that was the cause of the strongest smells.
"Since we have been investigating the problems, we have received no further complaints of odour. However, we will continue to monitor the site to ensure it complies with its environmental requirements. In the meantime, we would encourage residents to report any problems of odour to our incident hotline on 0800 807060."
Residents had been concerned that animal parts or animals blood were being spread on local fields, and this week the Environment Agency spokesman confirmed that the matter was a treated by-product of animal waste.
He said the waste, which came in liquid form and a more solid form, was not manure.
"This particular waste is the effluent from processing of animals for the food industry, so some of it does include blood etc," he said.
Local people called for urgent action after the over-whelming foul smell was particularly bad over recent Bank Holiday weekends - and they insisted the stench was not simple muck spreading. They believed that the noxious smell pervading the area was coming from animal parts or blood – and they stressed their concerns about potential health implications.
They said the desperate situation was forcing them to keep their children indoors and their windows closed when the smell was at its worst.
One of them Karen Morris, who lives near Yeadon Tarn, described the smell as “dreadful” – and said it was so bad that her neighbour didn’t like to let her children play out.
"The rumours are that the awful smell is animal blood and animal waste – it is not manure, it is like dead bodies,” she said.