* Opponents of the nuclear freeze initiative (Proposition 12) on the Nov. 2 California ballot haven't had enough money to mount a strong campaign. But with a $15,000 donation from the American Security Council, a Virginia-based political action group, the anti-freeze Californians for a Strong America will air three television commercials just before the election.
Meanwhile, the pro-freeze Citizens for Common Sense in National Defense continues a well-financed media campaign. Polls indicate probable approval of the initiative, which requires the governor of California formally to press for a US-Soviet agreement to halt testing, production, and deployment of nuclear weapons.
* Still trying to get its Diablo Canyon nuclear power plant near San Luis Obispo on line, the San Francisco-based Pacific Gas & Electric Company, which serves most of northern and central California, heard some good news Oct. 20. An official of the Nuclear Regulatory Commission said in a briefing that Diablo should be able to load fuel and start test operations next spring. NRC staff director Harold Denton said an inspection and modification program ''unprecedented in the history of nuclear power'' has been conducted since the Diablo Canyon plant's license was suspended late last year. Though many ''minor modifications'' have been made, Mr. Denton said, no major safety problems were found.