Johannesburg — A matter of months before starting up its first nuclear power station, South Africa is trying to defuse suspicions that its intentions in this field are not entirely peaceful.
While new assurances from South Africa have been welcomed by some, they still fall short of the steps sought by many in the international community who are dedicated to stemming the spread of nuclear weapons.
The chairman of South Africa's Atomic Energy Corporation, Dr. J. W. L. de Villiers, said in an interview that South Africa has agreed to abide by the ''spirit, principles, and goals'' of the Treaty on the Non-Proliferation of Nuclear Weapons and ''will not contribute to the proliferation problem.''
It will make this contribution by not allowing export of any nuclear-related materials or technology to any country that does not allow outside inspections of its nuclear facilities.
South Africa itself has so far refused to accept inspection of its nuclear plants but Dr. de Villiers would resume discussions with the United Nations International Atomic Energy Agency (IAEA) about the possibility of inspections of its semicommercial uranium enrichment plant at Valindaba.
The United States has said it is ''pleased'' that South Africa had taken this ''important step.'' But the US also made clear in a statement on the subject that it still wants South Africa to sign the Non-Proliferation Treaty (NPT) and accept outside inspections of its nuclear facilities. South Africa will continue its stand against signing the NPT, Dr. de Villiers says.
Concern about South Africa's nuclear program was heightened in 1977 when Pretoria, the nation's administrative capital, appeared to be preparing a nuclear test site in the Kalahari desert. The United States and other Western nations pressured South Africa to discontinue whatever it was preparing for in the desert.
Dr. de Villiers said suspicions about South Africa's nuclear program were unfounded, but he made clear South Africa was not overly worried about those suspicions.
''We're interested only in civil applications'' of nuclear technology, he said. He added, ''The world can think what it likes.''
Many analysts have felt that South Africa benefits in a political sense from keeping the rest of black Africa and other potential enemies guessing about its nuclear program. Some analysts believe this is the reason South Africa has not implemented inspections or signed the NPT.
When South Africa's first nuclear power station begins operation some time in the next few months, it will be a demonstration of the country's ability to withstand outside pressure on nuclear issues.
The United States was to be the supplier of enriched uranium to South Africa for the start-up of the Koeberg Power Plant north of Cape Town. But the US suspended such exports in 1975 and has refused to ship enriched uranium to South Africa until it signs the Non-Proliferation Treaty and accepts inspections.
However, US leverage was diminished when South Africa in 1981 obtained the necessary enriched uranium from other sources.
South Africa says its major concern is with inspections, which are called for under the NPT. The country has developed its own enrichment technique and claims proprietary concerns have made it reluctant to accept inspections of the Valindaba facility.
South Africa has accepted inspections of the new Koeberg plant.
Dr. de Villiers said arriving at an acceptable inspections procedure for Valindaba ''will be difficult'' since the plant was not designed with such inspections in mind.
Dr. de Villiers said the smaller pilot uranium enrichment plant also located at Valindaba is not even under consideration for inspections. Since this pilot plant is experimental and not designed for commercial production, and also not designed to accommodate inspections, Dr. de Villiers said it would not be discussed with the International Atomic Energy Agency.
The IAEA performs inspections of nuclear facilities around the world. And the UN organization's own tendentious relationship with South Africa may make an agreement on inspections difficult, analysts say.
South Africa was voted off the IAEA's board of governor's in 1977 and, although still a member of the body, it is not allowed to attend the organization's general conferences.
The IAEA, ''is politicized,'' says Dr. de Villiers.
The chairman of the Atomic Energy Corporation says international moves to isolated South Africa were one of the reasons the dialogue between South Africa and the IAEA broke down initially.
Speaking of the early days of South Africa's nuclear program some 20 years ago, de Villiers says this country originally wanted to build a uranium enrichment plant with another foreign country. But since South Africa could not find a partner, ''We went ahead on our own and didn't pursue discussions with the IAEA,'' says Dr. de Villiers.