QUESTIONS are being asked about the thoroughness of land survey tests carried out 10 years ago on land in Leftwich. Houses on the Muirfield Close estate were built on the site of a former waste tip and the area is now under investigation following the deaths of two little girls - Rebecca Watts and Sharon Pymer - from a rare and aggressive form of leukaemia.

New tests are being conducted to establish if there is a link between the deaths of the girls and toxic emissions from the former tip.

Now Rebecca's father John, of Muirfield Close, is questioning whether the houses should have been built in the first place

He says strata tests carried out on behalf of Muir Housing, which built the estate, show only three bore holes were sunk over the whole area and high levels of mercury were found.

John said: "It was only 10 years ago these tests were carried out and although times have changed and tests are usually carried out more thoroughly, I'm not happy at all. "One of the bore holes happens to be underneath my house."

Clr Dennis Ford, Vale Royal Borough Council's lead councillor for environmental health, said: "Strata Surveys Ltd produced a report on behalf of the developers in November 1994 as part of the planning process.

"It looked at various matters including ground conditions and gas emissions as it was known at the time that the land had been tipped on.

"Even if the report was adequate 10 years ago, regulations have since changed and it does not provide the answers we need today."

Since the survey took place, the standard that determines the number and location of bore holes has been updated and risk assessment procedures have been revised. New sampling criteria and contamination guideline values have also been introduced.

Clr Ford added: "We have looked in detail at the Strata Surveys report and we will need to assess the adequacy of the methods employed and its results further.

"However, the main focus of current investigations is on starting and carrying out the on site studies."