A Mississippi television station executive is trying to intervene in Mississippi Power and Light's plans to build a 2500-megawatt dual reactor nuclear power plant in Port Gibson, Miss.

Raymond J. McGrath, public affairs director of WJTV in Jackson, Miss., has filed objections to the plant with the Atomic Energy Commission(AEC), on the grounds that MP&L has not fully considered possible ways of making the plant safer.

Symbolic Gesture

McGrath asked the AEC earlier this month to allow him to withdraw as an intervener, on the condition that the AEC board hearing MP&L's request for a plant license consider all his objections.

The AEC has not yet granted McGrath's petition to withdraw. However, McGrath said yesterday that he probably will be allowed to withdraw, and that the AEC will have to investigate his objections because they have been raised during previous hearings on the plant.

Harvard-Owned

MP&L is a subsidiary of Middle South Utilities Inc. Harvard is the largest single stockholder in Middle South with 560,000 shares, yesterday worth about $9.2 million.

Two other Middle South subsidiaries--Arkansas Power and Light and Louisiana Power and Light--are also under attack from environmentalists who charge that the plants the utilities plan to build will be environmentally harmful.

McGrath's original objections to the MP&L plant were:

* that MP&L has not considered the idea of building the plant underground so that it would be safer;

* That MP&L has not considered adapting the plant to produce geothermal rather than nuclear power;

* that the plant as now planned will release radioactive matter into the atmosphere, although with proper planning this radioactive release could be eliminated; and,

* that Mississippi bears the entire financial burden for building the plant--it will cost $1 billion--while its power will be used in Louisiana and Arkansas also.

McGrath has, however, completely withdrawn the last two objections and hopes that the AEC will assume responsibility for looking into the other two.

The issue of radioactive release, McGrath said, is too complex for him to judge, and it may be impossible to eliminate radioactive emissions completely.