§ Lord Graham of Edmontonasked Her Majesty's Government:
With reference to Viscount Ullswater's speech during the Second Reading of the Coal Industry Bill (H.L. Deb, 9th February 1990, col. 1061), what contract bids were made by the Minestone Executive for which minestone was not entirely suitable; on what basis the Department of Transport concluded in 1986 that minestone was not entirely suitable for civil engineering projects; and whether they are satisfied that the Minestone Executive uses a sophisticated regime of tests to ensure that any material supplied to contractors meets the appropriate specification.
§ Viscount DavidsonThe Department of Transport cannot generally identify tenders for road contracts 725WA on which suppliers have made unsuccessful bids to tenderers. Tenderers are free to obtain bids for materials from whichever supplier can match the specified requirements, but the department would normally only be aware of successful suppliers to successful tenderers—and then only after the contract has been let.
Consistent with the department's policy of encouraging the use of waste materials where suitable, the current edition of the Specification for Highway Works, published in 1986, reaffirms the use of minestone as general filling. It does not permit the use of argillaceous stone, which includes minestone, for special application such as filling behind bridges. Such stone does not satisfy the necessary criteria to guard against settlement, corrosion and structural degradation.
It is for the contractor and his supplier to satisfy the department that material is consistently able to meet the specification. The purpose of testing is to achieve this and what testing regime is appropriate in any particular case will vary with the proposed use and type of minestone.