The owners of the San Onofre nuclear complex in California want to conduct a study using the latest technology to better gauge earthquakes risks near the plant.
Southern California Edison said the planning had been in the works months before the March 11 earthquake and tsunami crippled the Fukushima Dai-ichi nuclear plant in Japan. The utility is currently reviewing the scope of the study.
Edison plans to submit the proposal in the coming weeks to the California Public Utilities Commission, which needs to approve it since the study will be covered by customer rates. It could end up costing more than the $21 million estimate.
Lawmakers have raised questions about the seismic safety of the state's coastal nuclear plants.
Edison officials have said San Onofre was built to withstand a magnitude-7 earthquake.