SAN ONOFRE NUCLEAR GENERATING STATION

12 Months Ended

Dec. 31, 2021

Regulated Operations [Abstract]

SAN ONOFRE NUCLEAR GENERATING STATION

REGULATORY MATTERS

REGULATORY ASSETS AND LIABILITIES

We show the details of regulatory assets and liabilities in the following table and discuss them below. With the exception of regulatory balancing accounts, we generally do not earn a return on our regulatory assets until such time as a related cash expenditure has been made. Upon the occurrence of a cash expenditure associated with a regulatory asset, the related amounts are recoverable through a regulatory account mechanism for which we earn a return authorized by applicable regulators, which generally approximates the three-month commercial paper rate. The periods during which we recognize a regulatory asset while we do not earn a return vary by regulatory asset.

REGULATORY ASSETS (LIABILITIES)
(Dollars in millions)
	December 31,
	2021		2020		2019
SDG&E:
Fixed-price contracts and other derivatives	$	(50)	$	(53)	$	8
Deferred income taxes recoverable (refundable) in rates	125		22		(108)
Pension and other postretirement benefit plan obligations	(7)		50		103
Removal obligations	(2,251)		(2,121)		(2,056)
Environmental costs	62		56		45
Sunrise Powerlink fire mitigation	122		121		121
Regulatory balancing accounts(1)(2)
Commodity – electric	77		72		102
Gas transportation	49		35		22
Safety and reliability	67		67		77
Public purpose programs	(107)		(158)		(124)
2019 GRC retroactive impacts	—		56		111
Wildfire mitigation plan	178		93		12
Liability insurance premium	110		79		24
Other balancing accounts	207		61		70
Other regulatory assets (liabilities), net(2)	119		72		(153)
Total SDG&E	(1,299)		(1,548)		(1,746)
SoCalGas:
Deferred income taxes recoverable (refundable) in rates	44		(82)		(203)
Pension and other postretirement benefit plan obligations	51		417		400
Employee benefit costs	31		37		44
Removal obligations	(627)		(685)		(728)
Environmental costs	34		36		40
Regulatory balancing accounts(1)(2)
Commodity – gas, including transportation	(146)		(56)		(118)
Safety and reliability	339		335		295
Public purpose programs	(183)		(253)		(273)
2019 GRC retroactive impacts	—		202		400
Liability insurance premium	16		7		4
Other balancing accounts	42		(65)		(11)
Other regulatory assets (liabilities), net(2)	142		75		(101)
Total SoCalGas	(257)		(32)		(251)
Sempra Infrastructure:
Deferred income taxes recoverable in rates	77		80		83
Other regulatory assets	—		—		6
Total Sempra	$	(1,479)	$	(1,500)	$	(1,908)

(1)    At December 31, 2021, 2020 and 2019, the noncurrent portion of regulatory balancing accounts – net undercollected for SDG&E was $358, $139 and $108, respectively, and for SoCalGas was $410, $218 and $500, respectively.

(2)    Includes regulatory assets earning a return authorized by applicable regulators, which generally approximates the three-month commercial paper rate.

Regulatory Assets Not Earning a Return

▪Regulatory assets arising from fixed-price contracts and other derivatives are offset by corresponding liabilities arising from purchased power and natural gas commodity and transportation contracts. The regulatory asset is increased/decreased based on changes in the fair market value of the contracts. It is also reduced as payments are made for commodities and services under these contracts. The related amounts are recovered in rates once these contracts are settled, generally within two years.

▪Deferred income taxes recoverable/refundable in rates are based on current regulatory ratemaking and income tax laws. SDG&E, SoCalGas and Sempra Infrastructure expect to recover/refund net regulatory assets/liabilities related to deferred income taxes over the lives of the assets, ranging from 5 to 69 years, that give rise to the related accumulated deferred income tax balances. Regulatory assets and liabilities include excess deferred income taxes resulting from statutory income tax rate changes and certain income tax benefits and expenses associated with flow-through items, which we discuss in Note 8.

▪Regulatory assets/liabilities related to pension and other postretirement benefit plan obligations are offset by corresponding liabilities/assets. The assets are recovered in rates as the plans are funded.

▪The regulatory asset related to employee benefit costs represents our liability associated with long-term disability insurance that will be recovered from customers in future rates as expenditures are made.

▪Regulatory liabilities from removal obligations represent cumulative amounts collected in rates for future asset removal costs in excess of cumulative amounts incurred (or paid).

▪Regulatory assets related to environmental costs represent the portion of our environmental liability recognized at the end of the period in excess of the amount that has been recovered through rates charged to customers. We expect this amount to be recovered in future rates as expenditures are made.

▪The regulatory asset related to Sunrise Powerlink fire mitigation is offset by a corresponding liability for the funding of a trust to cover the mitigation costs. SDG&E expects to recover the regulatory asset in rates as the trust is funded over a remaining 48-year period.

Regulatory Assets Earning a Return

▪Over- and undercollected regulatory balancing accounts reflect the difference between customer billings and recorded or CPUC-authorized amounts. Depreciation, taxes and return on rate base may also be included in certain accounts. Amounts in the balancing accounts are recoverable (receivable) or refundable (payable) in future rates, subject to CPUC approval. The adopted revenue requirements in the 2019 GRC FD associated with the period from January 1, 2019 through December 31, 2019 were recovered in rates over a 24-month period that began in January 2020.

Amortization expense on certain regulatory assets for the years ended December 31, 2021, 2020 and 2019 was $10 million, $9 million and $7 million, respectively, at Sempra, $5 million, $4 million and $3 million, respectively, at SDG&E, and $5 million, $5 million and $4 million, respectively, at SoCalGas.

SEMPRA CALIFORNIA

COVID-19 Pandemic Protections

In connection with the COVID-19 pandemic and at the direction of the CPUC, SDG&E and SoCalGas implemented certain measures to assist customers, including suspending service disconnections due to nonpayment for all customers (except for SoCalGas’ noncore customers), waiving late payment fees, and offering flexible payment plans. At the CPUC’s direction, SDG&E and SoCalGas are automatically enrolling residential and small business customers with past-due balances in long-term repayment plans.

In 2021, SDG&E and SoCalGas applied, on behalf of their customers, for financial assistance from the California Department of Community Services and Development under the California Arrearage Payment Program, which provided funds of $63 million and $79 million for SDG&E and SoCalGas, respectively. In the first quarter of 2022, SDG&E and SoCalGas received and will apply the amounts directly to eligible customer accounts to reduce past due balances.

SDG&E and SoCalGas have been authorized to track and request recovery of incremental costs associated with complying with customer protection measures implemented by the CPUC related to the COVID-19 pandemic, including costs associated with suspending service disconnections and uncollectible expenses that arise from customers’ failure to pay. SDG&E and SoCalGas expect to pursue recovery of small and medium-large commercial and industrial customers’ tracked costs in rates in future CPUC proceedings, which recovery is not assured. Uncollectible expenses related to residential customers are recorded in a two-way balancing account as we discuss below.

Disconnection OIR

In June 2020, the CPUC issued a decision to adopt certain customer protections to reduce residential customer disconnections and improve reconnection processes, including, among other things, imposing limitations on service disconnections, elimination of deposit requirements and reconnection fees, establishment of the AMP that provides successfully participating, income-qualified residential customers with relief from outstanding utility bill amounts, and increased outreach and marketing efforts. As permitted by the decision, SDG&E and SoCalGas have each established a two-way balancing account to record the uncollectible expenses associated with residential customers’ inability to pay their electric or gas bills, including as a result of the relief from outstanding utility bill amounts provided under the AMP.

CPUC GRC

The CPUC uses GRCs to set rates designed to allow SDG&E and SoCalGas to recover their reasonable operating costs and to provide the opportunity to realize their authorized rates of return on their investments.

In September 2019, the CPUC issued a final decision in the 2019 GRC approving SDG&E’s and SoCalGas’ test year revenues for 2019 and attrition year adjustments for 2020 and 2021, which was effective retroactively to January 1, 2019. This is the first GRC that includes revenues authorized for risk assessment mitigation phase activities.

The 2019 GRC FD approved a test year 2019 revenue requirement of $1,990 million for SDG&E’s combined operations ($1,590 million for its electric operations and $400 million for its natural gas operations) and $2,770 million for SoCalGas.

The increases include separately authorized components for O&M and capital-related costs, as follows:

AUTHORIZED REVENUE REQUIREMENT INCREASES FOR 2020 AND 2021
(Dollars in millions)
	2020 increase from 2019				2021 increase from 2020
	Revenue increase		Percent increase		Revenue increase		Percent increase
SDG&E:
O&M	$	20	2.64	%	$	19	2.47	%
Capital-related costs	114		9.74		83		6.47
Total increase	$	134	6.74		$	102	4.83
SoCalGas:
O&M	$	36	2.64	%	$	34	2.40	%
Capital-related costs	184		14.36		116		7.93
Total increase	$	220	7.92		$	150	5.00

In January 2020, the CPUC issued a final decision implementing a four-year GRC cycle for California IOUs. SDG&E and SoCalGas were directed to file a petition for modification to revise their 2019 GRC to add two additional attrition years, resulting in a transitional five-year GRC period (2019-2023). In May 2021, the CPUC issued a final decision approving SDG&E’s and SoCalGas’ request to continue their authorized post-test year mechanisms for 2022 and 2023. For SDG&E, the decision authorizes revenue requirement increases of $87 million (3.92%) for 2022 and $86 million (3.70%) for 2023. For SoCalGas, the decision authorizes revenue requirement increases of $142 million (4.53%) for 2022 and $130 million (3.97%) for 2023.

The 2019 GRC FD approved SDG&E’s and SoCalGas’ establishment of two-way liability insurance premium balancing accounts, including wildfire insurance premium costs based on a specific level of coverage. The 2019 GRC FD also permits SDG&E and SoCalGas to seek recovery of additional liability insurance coverage.

The 2019 GRC FD clarified that differences between incurred and forecasted income tax expense due to forecasting differences are not subject to tracking in the income tax expense memorandum account beginning in 2019. SDG&E and SoCalGas previously recorded regulatory liabilities, inclusive of interest, associated with the 2016 through 2018 tracked forecasting differences of $86 million and $89 million, respectively. In April 2020, the CPUC confirmed treatment of the two-way income tax expense memorandum account for these 2016 through 2018 balances, at which time SDG&E and SoCalGas released these regulatory liability balances to revenues and regulatory interest.

CPUC Cost of Capital

A CPUC cost of capital proceeding determines a utility’s authorized capital structure and authorized return on rate base. In December 2019, the CPUC approved the cost of capital and rate structures (shown in the table below) for SDG&E and SoCalGas that became effective on January 1, 2020 and will remain in effect through December 31, 2022, subject to the CCM.

CPUC AUTHORIZED COST OF CAPITAL AND RATE STRUCTURE, SUBJECT TO THE CCM
SDG&E							SoCalGas
Authorized weighting		Return on rate base		Weighted return on rate base			Authorized weighting		Return on rate base		Weighted return on rate base
45.25	%	4.59	%	2.08	%	Long-Term Debt	45.60	%	4.23	%	1.93	%
2.75		6.22		0.17		Preferred Equity	2.40		6.00		0.14
52.00		10.20		5.30		Common Equity	52.00		10.05		5.23
100.00	%			7.55	%		100.00	%			7.30	%

The CCM applies in the interim years between required cost of capital applications and considers changes in the cost of capital based on changes in interest rates based on the applicable utility bond index published by Moody’s (the CCM benchmark rate) for each 12-month period ending September 30 (the measurement period). The CCM benchmark rate is the basis of comparison to

determine if the CCM is triggered, which occurs if the change in the applicable Moody’s utility bond index relative to the CCM benchmark rate is larger than plus or minus 1.000% at the end of the measurement period. The index applicable to SDG&E and SoCalGas is based on each utility’s credit rating. SDG&E’s CCM benchmark rate is 4.498% based on Moody’s Baa- utility bond index, and SoCalGas’ CCM benchmark rate is 4.029% based on Moody’s A- utility bond index. Alternatively, under the CCM, SDG&E and SoCalGas are permitted to file a cost of capital application in an interim year in which an extraordinary or catastrophic event materially impacts its cost of capital and affects utilities differently than the market as a whole.

For the measurement period ended September 30, 2021, the CCM would trigger for SDG&E because the average Moody’s Baa- utility bond index between October 1, 2020 and September 30, 2021 was 1.17% below SDG&E’s CCM benchmark rate of 4.498%. In August 2021, SDG&E filed an application with the CPUC to update its cost of capital effective January 1, 2022 due to the ongoing effects of the COVID-19 pandemic rather than have the CCM apply. In this application, SDG&E proposed to adjust its authorized capital structure by increasing its common equity ratio from 52% to 54%. SDG&E also proposed to increase its authorized ROE from 10.20% to 10.55% and decrease its authorized cost of debt from 4.59% to 3.84%. As a result, SDG&E’s proposed return on rate base would decrease from 7.55% to 7.46% if such application is approved by the CPUC as filed. SDG&E filed a joint motion with PG&E and Edison to consolidate all three utilities’ cost of capital applications given the overlapping issues of law and fact, which joint motion was granted in October 2021. In December 2021, the CPUC established a proceeding to determine if SDG&E’s cost of capital was impacted by an extraordinary event. If the CPUC finds that there was not an extraordinary event, the CCM would be effective retroactive to January 1, 2022 and would automatically adjust SDG&E’s authorized ROE from 10.20% to 9.62% and adjust its authorized cost of debt to reflect the then current embedded cost and projected interest rate. If the CPUC finds that there was an extraordinary event, it will then determine whether to suspend the CCM for 2022 and preserve SDG&E’s current authorized cost of capital or hold a second phase of the proceeding to set a new cost of capital for 2022. SDG&E expects a final decision in the second half of 2022. In December 2021, the CPUC granted SDG&E the establishment of memorandum accounts effective January 1, 2022 to track any differences in revenue requirement resulting from the interim cost of capital decision expected in 2022.

For the measurement period ended September 30, 2021, the CCM was not triggered for SoCalGas. SDG&E and SoCalGas are required to file their next cost of capital applications in April 2022 for a January 1, 2023 effective date.

SDG&E

FERC Rate Matters

SDG&E files separately with the FERC for its authorized ROE on FERC-regulated electric transmission operations and assets.

SDG&E’s TO4 ROE of 10.05% was the basis of SDG&E’s FERC-related revenue recognition until March 2020, when the FERC approved the settlement terms that SDG&E and all settling parties reached in October 2019 on SDG&E’s TO5 filing. The settlement agreement provided for a ROE of 10.60%, consisting of a base ROE of 10.10% plus an additional 50 bps for participation in the California ISO (the California ISO adder). If the FERC issues an order ruling that California IOUs are no longer eligible for the California ISO adder, SDG&E would refund the California ISO adder as of the refund effective date (June 1, 2019) if such a refund is determined to be required by the terms of the TO5 settlement. The TO5 term is effective June 1, 2019 and shall remain in effect each calendar quarter until terminated by a notice at least six months before the end of the calendar year. In 2020, SDG&E recorded retroactive revenues of $12 million related to 2019, and additional FERC revenues of $17 million to conclude a rate base matter, net of certain refunds to be paid to CPUC-jurisdictional customers.

Energy Efficiency Program Inquiry

In January 2020, the CPUC issued a ruling seeking comments on a report prepared by its consultant regarding SDG&E’s Upstream Lighting Program for the program year 2017. The CPUC subsequently expanded the scope of the comments to cover the program year 2018. The Upstream Lighting Program was one of SDG&E’s Energy Efficiency Programs designed to produce energy efficiency savings for which SDG&E could earn a performance-based incentive.

Pursuant to the CPUC ruling, intervenors representing ratepayers questioned SDG&E’s management of the program and alleged that certain program expenditures did not benefit the purpose of the program. As a result of the inquiry, SDG&E voluntarily expanded its review to include the program year 2019. Based on this review, SDG&E concluded that some concessions were appropriate, which include refunding certain costs to customers and reducing certain performance-based incentives. Accordingly, in the year ended December 31, 2020, SDG&E reduced revenues by $51 million and recorded a fine of $6 million in Other (Expense) Income, Net, on the SDG&E and Sempra Consolidated Statements of Operations. The after-tax impact for the year ended December 31, 2020 was $44 million. In October 2020, SDG&E executed a settlement agreement with intervenors consistent with these concessions. In September 2021, the CPUC approved the settlement agreement.

SOCALGAS

OSCs – Energy Efficiency and Advocacy

In October 2019, the CPUC issued an OSC to determine whether SoCalGas should be sanctioned for violation of certain CPUC code sections and orders relating to energy efficiency (EE) codes and standards advocacy activities, undertaken by SoCalGas following a CPUC decision disallowing SoCalGas’ future engagement in advocacy around such EE codes and standards. On February 3, 2022, the assigned Administrative Law Judge issued a Presiding Officer’s Decision (POD 1) that found that SoCalGas did undertake prohibited EE codes and standards advocacy activities using ratepayer funds. POD 1 imposes on SoCalGas a financial penalty of $10 million; customer refunds for certain ratepayer expenditures and shareholder incentives that SoCalGas estimates will be negligible; and a prohibition from recovering from ratepayers costs of proposed codes and standards activities until SoCalGas demonstrates policies, practices and procedures that adhere to the CPUC’s intent for codes and standards advocacy. POD 1 can be appealed within 30 days or be reviewed by any of the CPUC commissioners. If there are no appeals or commissioner requests for review, POD 1 automatically becomes the final decision of the CPUC. SoCalGas does not intend to appeal POD 1.

In December 2019, the CPUC issued a second OSC to determine whether SoCalGas is entitled to the EE program’s shareholder incentives for codes and standards advocacy in 2016 and 2017 (later expanded to include 2014 and 2015), whether its shareholders should bear the costs of those advocacy activities, and to address whether any other remedies are appropriate. In April 2021, the assigned Administrative Law Judge issued a Presiding Officer’s Decision (POD 2) on this second OSC. POD 2 finds no violations and assesses no fines or penalties but finds that SoCalGas spent ratepayer funds on activities that were not aligned with the CPUC’s intent for EE codes and standards advocacy, and orders customer refunds that SoCalGas estimates will be negligible. Additionally, POD 2 precludes SoCalGas from seeking cost recovery associated with EE codes and standards advocacy programs until lifted by the CPUC, and orders certain nonfinancial remedies. POD 2 was appealed by intervenors and in February 2022, the assigned Administrative Law Judge issued a modified POD 2 that substantially retains the original conclusions, including no fines or penalties. Also, in February 2022, a CPUC commissioner issued an alternative decision that imposes a financial penalty of $150,000. SoCalGas expects that both the modified POD 2 and the CPUC commissioner’s alternative decision will be heard at a CPUC meeting in March 2022.

If the CPUC were to assess fines, penalties or other restrictions on SoCalGas that are different from what has been ordered in POD 1 and the modified POD 2, they could be material to SoCalGas’ and Sempra’s results of operations, financial condition, cash flows and/or prospects.

SAN ONOFRE NUCLEAR GENERATING STATION

SDG&E has a 20% ownership interest in SONGS, a nuclear generating facility near San Clemente, California, which permanently ceased operations in June 2013 after an extended outage as a result of issues with the steam generators used in the facility. Edison, the majority owner and operator of SONGS, notified SDG&E that it had reached a decision to permanently retire SONGS and seek approval from the NRC to start the decommissioning activities for the entire facility. SONGS is subject to the jurisdiction of the NRC and the CPUC.

SDG&E, and each of the other owners, holds its undivided interest as a tenant in common in the property. Each owner is responsible for financing its share of costs. SDG&E’s share of operating expenses is included in Sempra’s and SDG&E’s Consolidated Statements of Operations.

NUCLEAR DECOMMISSIONING AND FUNDING

As a result of Edison’s decision to permanently retire SONGS Units 2 and 3, Edison began the decommissioning phase of the plant. Major decommissioning work began in 2020. We expect the majority of the decommissioning work to take approximately 10 years. Decommissioning of Unit 1, removed from service in 1992, is largely complete. The remaining work for Unit 1 will be completed once Units 2 and 3 are dismantled and the spent fuel is removed from the site. The spent fuel is currently being stored

on-site, until the DOE identifies a spent fuel storage facility and puts in place a program for the fuel’s disposal, as we discuss below. SDG&E is responsible for approximately 20% of the total decommissioning cost.

The Samuel Lawrence Foundation filed a writ petition under the California Coastal Act in LA Superior Court in December 2019 seeking to invalidate the coastal development permit and to obtain injunctive relief to stop decommissioning work. The petition was denied in September 2021. In December 2021, the foundation filed a notice of appeal. In September 2020, the foundation filed another writ petition under the California Coastal Act in LA Superior Court seeking to set aside the CCC’s July 2020 approval of the inspection and maintenance plan for the SONGS’ canisters and to obtain injunctive relief to stop decommissioning work. In December 2021, the foundation filed a request for dismissal. To date, decommissioning work has not been interrupted as a result of these writ petitions.

In accordance with state and federal requirements and regulations, SDG&E has assets held in the NDT to fund its share of decommissioning costs for SONGS Units 1, 2 and 3. Amounts that were collected in rates for SONGS’ decommissioning are invested in the NDT, which is comprised of externally managed trust funds. Amounts held by the NDT are invested in accordance with CPUC regulations. SDG&E classifies debt and equity securities held in the NDT as available-for-sale. The NDT assets are presented on the Sempra and SDG&E Consolidated Balance Sheets at fair value with the offsetting credits recorded in noncurrent Regulatory Liabilities.

Except for the use of funds for the planning of decommissioning activities or NDT administrative costs, CPUC approval is required for SDG&E to access the NDT assets to fund SONGS decommissioning costs for Units 2 and 3. In December 2021, SDG&E received authorization from the CPUC to access NDT funds of up to $78 million for forecasted 2022 costs.

In September 2020, the IRS and the U.S. Department of the Treasury published final regulations that clarify the definition of “nuclear decommissioning costs,” which are costs that may be paid for or reimbursed from a qualified trust fund. The final regulations adopted most of the provisions of the proposed regulations issued in December 2016. The final regulations apply to taxable years ending on or after September 4, 2020 and confirm that the definition of “nuclear decommissioning costs” includes amounts related to the storage of spent nuclear fuel at both on-site and off-site ISFSIs.

The final regulations also clarify that costs incurred for ISFSIs that may be or are expected to be reimbursed by the DOE may be paid or reimbursed from a qualified trust fund. Accordingly, the final regulations allow SDG&E the option to access qualified trust funds to recover spent fuel storage costs before Edison reaches final settlement with the DOE regarding the DOE’s reimbursement of these costs. Historically, the DOE’s reimbursements of spent fuel storage costs have not resulted in timely or complete recovery of these costs. We discuss the DOE’s responsibility for spent nuclear fuel below.

Nuclear Decommissioning Trusts

The following table shows the fair values and gross unrealized gains and losses for the securities held in the NDT on the Sempra and SDG&E Consolidated Balance Sheets. We provide additional fair value disclosures for the NDT in Note 12.

NUCLEAR DECOMMISSIONING TRUSTS
(Dollars in millions)
	Cost		Gross unrealized gains		Gross unrealized losses		Estimated fair value
At December 31, 2021:
Debt securities:
Debt securities issued by the U.S. Treasury and other U.S. government corporations and agencies(1)	$	56	$	—	$	—	$	56
Municipal bonds(2)	309		13		(1)		321
Other securities(3)	255		7		(2)		260
Total debt securities	620		20		(3)		637
Equity securities	104		262		(2)		364
Short-term investments, primarily cash equivalents	3		—		—		3
Receivables (payables), net	8		—		—		8
Total	$	735	$	282	$	(5)	$	1,012
At December 31, 2020:
Debt securities:
Debt securities issued by the U.S. Treasury and other U.S. government corporations and agencies	$	64	$	1	$	—	$	65
Municipal bonds	308		18		—		326
Other securities	253		17		—		270
Total debt securities	625		36		—		661
Equity securities	112		254		(2)		364
Short-term investments, primarily cash equivalents	3		—		—		3
Receivables (payables), net	(9)		—		—		(9)
Total	$	731	$	290	$	(2)	$	1,019
At December 31, 2019:
Debt securities:
Debt securities issued by the U.S. Treasury and other U.S. government corporations and agencies	$	57	$	—	$	—	$	57
Municipal bonds	270		12		—		282
Other securities	218		9		(1)		226
Total debt securities	545		21		(1)		565
Equity securities	176		339		(6)		509
Short-term investments, primarily cash equivalents	16		—		—		16
Receivables (payables), net	(8)		—		—		(8)
Total	$	729	$	360	$	(7)	$	1,082

(1)    Maturity dates are 2022-2052.

(2)    Maturity dates are 2022-2056.

(3)    Maturity dates are 2022-2072.

The following table shows the proceeds from sales of securities in the NDT and gross realized gains and losses on those sales.

SALES OF SECURITIES IN THE NUCLEAR DECOMMISSIONING TRUSTS
(Dollars in millions)
	Years ended December 31,
	2021		2020		2019
Proceeds from sales	$	961	$	1,439	$	914
Gross realized gains	67		156		24
Gross realized losses	(5)		(17)		(5)

Net unrealized gains and losses, as well as realized gains and losses that are reinvested in the NDT, are included in noncurrent Regulatory Liabilities on Sempra’s and SDG&E’s Consolidated Balance Sheets. We determine the cost of securities in the trusts on the basis of specific identification.

ASSET RETIREMENT OBLIGATION

The present value of SDG&E’s ARO related to decommissioning costs for all three SONGS units was $568 million at December 31, 2021 and is based on a cost study prepared in 2020, which will be submitted to the CPUC in the first half of 2022. The ARO for Units 2 and 3 reflects the acceleration of the start of decommissioning of these units as a result of the early closure of the plant. We expect SDG&E’s undiscounted SONGS decommissioning payments to be $79 million in 2022, $66 million in 2023, $77 million in 2024, $46 million in 2025, $52 million in 2026, and $718 million thereafter.

U.S. DEPARTMENT OF ENERGY NUCLEAR FUEL DISPOSAL

Spent nuclear fuel from SONGS is currently stored on-site in an ISFSI licensed by the NRC. The ISFSI will operate until 2049, when it is assumed that the DOE will have taken custody of all the SONGS spent fuel. The ISFSI would then be decommissioned, and the site restored to its original environmental state. Until then, SONGS owners are responsible for interim storage of spent nuclear fuel at SONGS.

The Nuclear Waste Policy Act of 1982 made the DOE responsible for accepting, transporting, and disposing of spent nuclear fuel. However, it is uncertain when the DOE will begin accepting spent nuclear fuel from SONGS. This delay will lead to increased costs for spent fuel storage. In November 2019, Edison filed a claim for spent fuel management costs in the U.S. Court of Federal Claims for the time period from January 2017 through July 2018, which is pending DOE approval. It is unclear when Edison will pursue litigation claims for spent fuel management costs incurred on or after August 1, 2018. SDG&E will continue to support Edison in its pursuit of claims on behalf of the SONGS co-owners against the DOE for its failure to timely accept the spent nuclear fuel.

NUCLEAR INSURANCE

SDG&E and the other owners of SONGS have insurance to cover claims from nuclear liability incidents arising at SONGS. Currently, this insurance provides $450 million in coverage limits, the maximum amount available, including coverage for acts of terrorism. In addition, the Price-Anderson Act provides an additional $110 million of coverage. If a nuclear liability loss occurs at SONGS and exceeds the $450 million insurance limit, this additional coverage would be available to provide a total of $560 million in coverage limits per incident.

The SONGS owners have nuclear property damage insurance of $130 million, which exceeds the minimum federal requirements of $50 million. This insurance coverage is provided through NEIL. The NEIL policies have specific exclusions and limitations that can result in reduced coverage. Insured members as a group are subject to retrospective premium assessments to cover losses sustained by NEIL under all issued policies. SDG&E could be assessed up to $4.3 million of retrospective premiums based on overall member claims.

The nuclear property insurance program includes an industry aggregate loss limit for non-certified acts of terrorism (as defined by the Terrorism Risk Insurance Act) of $3.24 billion. This is the maximum amount that will be paid to insured members who suffer losses or damages from these non-certified terrorist acts.