STRUCTURAL engineers with the Buildings Ordinance Office have written to the ICAC, calling for action to curb the corruption they say is rife in the department. Chairman of the Buildings Department's Structural Engineers' Association, Hui Kwok-hung, wrote to the Independent Commission Against Corruption (ICAC) Director of Corruption Prevention Tony Scott yesterday, amid claims by the association that a senior building surveyor had been investigated by the ICAC. In July, two senior government surveyors were arrested by the ICAC over allegations of bribery concerning building applications. Mr Hui said legislation allowed the department's officers to decide on their own when an occupation permit would be issued. ''It involves up to millions of dollars if one extra day is taken before the department can issue an occupation permit,'' he said. Mr Hui said his department had been involved in many corruption cases over the past few years. But the other professional union in the department, the Local Building Surveyors' Association, said Mr Hui was exaggerating. Chairman Lam Siu-tong said the ICAC had been monitoring the department regularly. Mr Hui said the association objected to the possibility of Principal Government Building Surveyor Tony Samson being appointed to head the new Buildings Department. Mr Samson was the head of the Buildings Ordinance Office in the old Buildings and Lands Department before the department was divided to form the Buildings Department and Lands Department in August. According to Mr Hui, Mr Samson had discriminated against local structural engineers. He said Mr Samson had adopted a ''provocative attitude'' when the association asked why he had terminated the contracts of five local officers but renewed those of eightoverseas officers last September. Mr Samson was not available for comment.