Both cases were brought by its western region under section 5 of the Health and Safety at Work Act 1974, which requires the use of the "best practicable means" (BPM) to prevent and render harmless emissions to air.
The first was brought against Pasminco Europe (Smelting) at Bristol Magistrates Court on 16 March. It concerned a four-hour leak of sulphur trioxide from the firm's zinc smelter at Avonmouth last June.
The site produces sulphuric acid from sulphur removed from ore concentrates in its sinter plant. The SO3 emission occurred after an acid leak forced the closure of the acid plant for repairs.
The court heard that a procedure for stopping a pump which fed SO3 to an absorber was not followed. The company then failed to observe a procedure agreed with HMIP in which a balloon at the base of the plant's stack should have been inflated to prevent the escape of unabsorbed SO3. This proved impossible because an electrical supply was not available. Pasminco pleaded guilty and was fined the statutory maximum of £2,000, with costs of £3,229.
In the second case, heard by Birmingham magistrates on 20 March, RMC Roadstone was fined £1,000, with £3,000 costs, in connection with an incident at its asphalt plant at Washwood Heath, Birmingham, last August.
The court heard that the company continued to operate the plant for almost two hours despite knowing that bags had burst in its bag filter, provoking public complaint about grit and dust emissions. Another RMC operation was convicted last October of knowingly operating without a permit (ENDS Report 201, p 37 ), and the two cases point to an attitude problem among the firm's site managers.
Future prosecutions of this kind may attract higher penalties. The maximum fine available to magistrates under the 1974 Act has just been raised from £2,000 to £20,000 by the Offshore Safety Act.