BOSSES at a cement plant have been told to carry out 'environmental patrols' to help monitor the emissions it releases into the air.

The Government's Environment Agency has changed Castle Cement's operating licence at its Ribblesdale plant, demanding the company carries out at least two patrols each day.

Chris Smith, the agency's Industry Regulation Area Team Leader, said: "Castle Cement will be expected to carry out these patrols on a regular basis.

"A monthly summary of any steps taken as a result of these observations, and its response to public complaints, will be made available for inspection to the public."

The agency says that all air quality standards in Clitheroe are currently being met.

"But the Enviroment Agency is aware that haze and odour from processes at the plant have caused complaints from local people," a spokesperson added.

A spokesman for Castle Cement said today the patrols would involve one or two employees touring the area of the emissions plume -- not just in Clitheroe but across the Ribble Valley-- in a van, keeping a look-out for any emission effects.

Last week,the company announced a separate £500,000 project to help monitor emissions.

Analytical Environmental Services has been contracted for three years to monitor the emissions from the Ribblesdale site in Clitheroe, as well as from its two other manufacturing sites at Padeswood in North Wales and Ketton in Rutland.

Castle Cement says it has a strict environmental policy in place to ensure that fine dust and gases from its production process comply with Environment Agency regulations.

Ian Sutheran, Castle Cement's general manager at the Ribblesdale works, said: "We are committed to caring for the environment by including environmental considerations in business decisions made at all levels of the company."

The cement manufacturer employs more than 400 people at Ribblesdale.

Campaigner Mary Horner, of Bolton-by-Bowland, said: "It isn't the first time that Castle Cement has conducted air emission monitoring and we are still none the wiser as to whether the air is actually safe or not."