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Contingencies and Legal Proceedings Contingencies (Details) $ in Millions | 6 Months Ended |
--- | --- | ---
Mar. 31, 2024 USD ($) reactors Procedures Insurance_layers | Sep. 30, 2023 USD ($)
Loss Contingencies |  |
Nuclear liability insurance | $ 500 |
Assessment from licensees for each licensed reactor | $ 166 |
Number of licensed reactors in US | reactors | 95 |
Nuclear accident assessment limitation per year per unit | $ 25 |
Maximum assessment per nuclear incident | 1,200 |
Total amount of protection available | 16,300 |
Amount of insurance available for loss at any one site | 2,100 |
Maximum amount of retrospective premiums | 114 |
Maximum idemnity if a covered accident takes or keeps a nuclear unit offline | 490 |
Maximum retrospective premiums | 44 |
Estimated future decommissioning cost | $ 7,592 | $ 7,489
Number of procedures for determining estimates for the costs of nuclear decommissioning | Procedures | 2 |
Possible additional future costs for compliance with Clean Air Act requirements | $ 200 |
Possible additional future costs for compliance with CCR requirements | 1,500 |
Possible additional future costs for compliance with Clean Water requirements. | 173 |
Estimated liability for cleanup and environmental work | 16 | 16
Amount of insurance available for loss at any one site (top range) | 2,800 |
Long-term debt of VIEs, net (including current maturities) | $ 949 | 927
The U.S. Congress is required to take action if these layes are exhausted | Insurance_layers | 2 |
Environmental Remediation |  |
Loss Contingencies |  |
Accrual for Environmental Loss Contingencies, Significant Assumptions | 62 million |
Accrual for Environmental Loss Contingencies, Significant Assumptions | 62 million |
Nuclear |  |
Loss Contingencies |  |
Estimated future decommissioning cost | $ 3,730 | 3,808
Non-nuclear |  |
Loss Contingencies |  |
Estimated future decommissioning cost | $ 3,862 | $ 3,681

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