TOKYO (Reuters) - Detailed findings from a Reuters reactor-by-reactor analysis of Japan’s nuclear sector show Japan may get as few as six more reactors operating in the next five years and will miss a government target to have 30 operating by 2030.

The findings follow a reactor-by reactor review of all units that have not won the final green light to restart, looking at legal, disaster and political risks, along with a consideration of upgrade costs.

Reuters reviewed thousands of documents submitted to the country’s nuclear regulator, sent questionnaires to all operators and interviewed industry professionals, lawyers and other experts.

Nuclear operators say they have spent or will probably spend 4 trillion yen ($36 billion) on safety upgrades to meet the new standards.

This includes building tsunami protection barriers, beefing up buildings’ seismic resistance, fireproofing wiring and upgrading piping and other equipment.

The following table lays out the prospects for restarts for Japan’s 38 reactors, based on the analysis. While the analysis was being done, Tohoku Electric announced plans to decommission the No. 1 reactor at its Onagawa station. The analysis had found that the reactor was unlikely to restart.