Water chiefs today pledged to monitor a polluted site in Thornbury as contractors worked on a £3 million sewage scheme.

The assurances from Yorkshire Water came as worried residents near the former GEC foundry site in Dick Lane said they feared for their safety.

The families said they were also concerned that the workers carrying out the project were not wearing protective clothing, despite contamination.

A specialist consultant who investigated the site for the owners two years ago recommended that workers should not routinely come into skin contact with sand on the site or swallow it.

The consultants' report, considered by Leeds councillors when they dealt with a planning application for owners Harrogate-based Gregory Properties, said there was contamination from metal on part of the site.

The consultant said it was just above the level where remedial steps were advisable. The report said the heath risk to people off the site was small.

The land is already the centre of controversy because the company wants to develop a £20 million office and restaurant scheme.

Families are fighting the development on road safety and disturbance grounds and say they also fear problems from pollution.

The work being carried out is not part of the planned office and restaurant development, but the replacement of sewers beneath Dick Lane by Yorkshire Water as part of a £3 million improvement scheme.

A spokesman from Yorkshire Water said the company had also carried out tests.

He said: "Nothing above the threshold level has been found. We will do periodic tests and complete monitoring of the situation but this work is surface work. In any situation our contractors take every precaution necessary to ensure the safety of the workers."

But a spokesman for the residents said digging had been carried out and machinery brought on site yesterday.

Conservative ward councillor Andrew Carter said he was contacting Leeds Council. A Leeds Council spokesman said the situation had not changed since the report was prepared and the contamination was only on one part of the site.

Converted for the new archive on 30 June 2000. Some images and formatting may have been lost in the conversion.