Industries that discharge wastes into rivers, lakes and streams are required by law to clean up their acts by 1984. The Environmental Protection Agency recently issued regulations for the iron and steel industry, one of the 24 for which EPA must draw up standards. The new rules–designed to remove pollutants such as ammonia, fluoride, solids, oil and toxic substances–will cost industry about $310 million to modify existing facilities. That’s signficantly less than the $1 billion it was estimated that the iron and steel industry would have had to pay under a proposal submitted in the closing days of the Carter administration.

The only industry for which EPA has completed the regulations is the timber industry. EPA is on a schedule set by a 1976 consent decree to issue regulations for the other 22 industries in the next 18 months, something it says will be extremely difficult. But its pleas for more time were rejected recently by a federal court here.