The Wellcome Trust's board of governors met on Wednesday to discuss the siting of the United Kingdom's Pounds 200 million X-ray source for biomedical and physical sciences research. The trust, which is contributing Pounds 110 million to the project, said it would report the outcome of the meeting to the Department of Trade and Industry. Unions at Daresbury Laboratory, Warrington, which was regarded as the chosen site until early this year, have accused the trust of lobbying to have the source located at Rutherford Appleton Laboratory in Oxfordshire. A decision is expected in the next two weeks.