§ Mr. Smithersasked the Parliamentary Secretary for Science what was the date of the report tendered by the Geological Survey to the Gas Council which makes important stipulations as to the precautions necessary to avoid risks of fire, contamination and subsidence in the event of gas being stored underground beneath the City of Winchester and the adjoining countryside.
§ Mr. Denzil FreethWhen approached by the Gas Council in October, 1961, the Geological Survey advised the Council that supplementary boreholes and further geological work should be undertaken. After these boreholes and some of the other work had been completed, the Geological Survey transmitted a memorandum, dated 9th February, 1962, which was received by the Minister for Science on 13th February, 1962, for the guidance of my right hon. Friend the Minister of Power; this included references to various precautions which the Survey recommended.
§ Mr. Smithersasked the Parliamentary Secretary for Science what was the cubic capacity smaller than that proposed by the Gas Council which the Geological Survey advised to be the maximum not to be exceeded if the danger of fire contamination or subsidence is to be avoided in connection with the proposal 78W to store gas underground beneath the City of Winchester and the adjacent countryside.
§ Mr. Denzil FreethThe proposal was to store gas in the Lower Greensand, in the geological anticlinal arch which has its centre below the neighbourhood of Chilcomb. The Geological Survey advised that gas might be stored in this formation, at the pressures originally proposed by the Gas Council, down to a depth at which the upper surface of the Lower Greensand was not under 500 feet below sea level. The Survey advised that, if this were done, and various precautions were taken, it would be possible to confine the gas to the Chilcomb anticline. Before recommending agreement to the storage of additional gas, in that part of the Lower Greensand which has its upper surface between 500 and 555 feet below sea level—the depth limit originally proposed by the Gas Council—the Geological Survey advised that further exploratory boreholes, at the extremities of the anticlinal structure, would be necessary. Other precautions recommended by the Survey were listed in my supplementary reply to my hon. Friend on 27th February.