A top official of the Environmental Protection Agency yesterday attacked a Union Carbide Corp. advertising campaign which claims that government environmental policies have contributed to the nation's energy supply problems.

EPA deputy adminstrator Barbara Blum said Union Carbide's claim "simply does not square with the truth."

In a speech before the Gas Men's Roundtable in Washington, Blum agreed with the ad's claim that cleanup costs are high for Carbide's industrial-scale boilers using coal instead of oil.

"But the bigger point is . . . today there are huge quantities of homegrown coal that can be mined and burned, providing American jobs and stemming the dangerous trend of buying more and more of our from uncertain freight sources. To use coal, however, the public must have reassurance that it is being burned in a way that will not endanger their health and safety," Blum said.

The Union Carbide ads, which appear in the Washington Post and other newspapers, contend that the company is being squeezed by contradictory government energy and environmental policies.

Carbide claims that a lack of coordination between energy and enviornmental policy has led to "conflicting directives to the private sector and inefficient use of scarce resources."

"Because Union Carbide depends on reliable supplies of energy," the ad states, "national environmental policies which restrict energy supplies have a direct impact on our business."

For example, the ad notes, its coal-fired boiler, complete with coal yards, unloading facilities and environmental protection equipment costs about five times more to build than an oil-fired boiler of the same scale.

"Union Carbide analyses show that environmental protection costs are typically about 50 percent of the costs of installing a coal-fired boiler," said the ad.

In her speech, Blum said "The President recognized long ago that the time is past for a national debate on the relative merits of energy production, energy conservation and environmental protection.

"We must do them all," she said.

She denied an implication in the ad that EPA's new emission standards for power plants will decrease the use of coal and increase oil comsumption by the nation's utilities.

"Nothing could be further from the truth," she said. "The regulations we put into place to protect public health and the environment will allow, indeed encourage, large quantities to coal to be burned in some 350 new plants by 1995."

Blum pointed out that the government can, and has, when it deemed necessary, waived certain regulations.

"To help shorten gas lines last summer, we temporarily waived certain EPA requirements. It was not an easy decision, since the result would be an increase in lead and hydrocarbon emissions. The alternative, however, was worse -- massive fuel-switching (drivers using leaded gasoline in cars designed for unleaded) that could have wiped out millions of dollars in automotive air pollution equipment."