Indicate by check mark whether the registrant: (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. Yes ☒ No ☐

Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit such files). Yes ☒ No ☐

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “non-accelerated filer,” “smaller reporting company” and "emerging growth company" in Rule 12b-2 of the Exchange Act.

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act). Yes ☐ No ☒

Indicate the number of shares outstanding of each of the issuer’s classes of common stock, as of the latest practicable date. At April ~~17, 2020,~~23, 2021, Dominion Energy South Carolina, Inc. had outstanding 40,296,147 shares of common stock, all of which were held by SCANA Corporation, a wholly-owned subsidiary of Dominion Energy, Inc.

Dominion Energy South Carolina, Inc. meets the conditions set forth in General Instruction H(1)(a) and (b) of Form 10-Q and therefore is filing this Form with the reduced disclosure format allowed under General Instruction H(2).

The following abbreviations or acronyms used in this Form 10-Q are defined below:

Abbreviation or Acronym		Definition
2017 Tax Reform Act		An Act to Provide for Reconciliation Pursuant to Titles II and V of the Concurrent Resolution on the Budget for Fiscal Year 2018 (previously known as The Tax Cuts and Jobs Act) enacted on December 22, 2017
ACE Rule		Affordable Clean Energy Rule
AOCI		Accumulated other comprehensive income (loss)
ARO		Asset retirement obligation
BACT		Best available control technology
BLRA		South Carolina Base Load Review Act
CAA		Clean Air Act
~~CARES Act~~		~~Coronavirus Aid, Relief and Economic Security Act enacted on March 27, 2020~~
CCR		Coal combustion residual
CEO		Chief Executive Officer
CERCLA		Comprehensive Environmental Response, Compensation and Liability Act of 1980, also known as Superfund
CFO		Chief Financial Officer
CO₂		Carbon dioxide
Consortium		A consortium consisting of Westinghouse and WECTEC
CUA		Capacity Use Area
CWA		Clean Water Act
DECG		Carolina Gas Transmission, LLC, (formerly known as Dominion Energy Carolina Gas Transmission, ~~LLC~~LLC), a subsidiary of Berkshire Hathaway Energy Company effective November 2020 (previously a subsidiary of Dominion Energy)
DES		Dominion Energy Services, Inc.
DESC		The legal entity, Dominion Energy South Carolina, Inc., one or more of its consolidated entities or operating segment, or the entirety of Dominion Energy South Carolina, Inc. and its consolidated entities
DESS		Dominion Energy Southeast Services, Inc.
Dominion Energy		The legal entity, Dominion Energy, Inc., one or more of its consolidated subsidiaries (other than DESC) or operating segments, or the entirety of Dominion Energy, Inc. and its consolidated subsidiaries
Dominion Energy ~~Gas~~		~~The legal entity, Dominion Energy Gas Holdings, LLC, a~~ ~~wholly-owned subsidiary of Dominion Energy,~~ ~~one or more of its consolidated subsidiaries or operating segment, or the entirety of Dominion Energy Gas Holdings, LLC and its consolidated subsidiaries~~
~~Dominion Energy~~ South Carolina		Dominion Energy South Carolina operating segment
DSM		Demand-side management
ELG Rule		Effluent limitations guidelines for the steam electric power generating category
EMANI		European Mutual Association for Nuclear Insurance
EPA		U.S. Environmental Protection Agency
~~Exchange Act~~		~~Securities Exchange Act of 1934, as amended~~
FERC		Federal Energy Regulatory Commission
FILOT		Fee in lieu of taxes
Fuel Company		South Carolina Fuel Company, Inc.
GAAP		U.S. generally accepted accounting principles
GENCO		South Carolina Generating Company, Inc.
GHG		Greenhouse gas
IAA		Interim Assessment Agreement dated March 28, 2017, as amended, among DESC, Santee Cooper, Westinghouse and WECTEC
~~MATS~~		~~Utility Mercury and Air Toxics Standard Rule~~
MD&A		Management's Discussion and Analysis of Financial Condition and Results of Operations
MGD		Million gallons a day
MGP		Manufactured gas plant
NEIL		Nuclear Electric Insurance Limited

(millions)	March 31, 2020			December 31, 2019			March 31, 2021			December 31, 2020
ASSETS
Utility plant in service	$	13,293		$	13,208		$	13,865		$	13,680
Accumulated depreciation and amortization		(4,889	)		(4,851	)		(5,077	)		(5,027	)
Construction work in progress		339			339			398			460
Nuclear fuel, net of accumulated amortization		208			219			216			221
Utility plant, net ($714 and $727 related to VIEs)		8,951			8,915
Utility plant, net ($726 and $730 related to VIEs)								9,402			9,334
Nonutility Property and Investments:
Nonutility property, net of accumulated depreciation		68			69			38			39
Assets held in trust, nuclear decommissioning		209			214			238			238
Nonutility property and investments, net		277			283			276			277
Current Assets:
Cash and cash equivalents		10			4			29			5
Receivables:
Customer, net of allowance for uncollectible accounts of $3 at both periods		304			320
Customer, net of allowance for uncollectible accounts of $9 and $10								297			365
Affiliated and related party		4			14			3			16
Other		102			119			94			64
Inventories (at average cost):
Fuel		103			104			63			68
Gas stored								11			14
Materials and supplies		169			168			167			176
Prepayments		87			91			70			75
Regulatory assets		260			271			226			229
Other current assets		30			27			21			27
Total current assets ($131 and $143 related to VIEs)		1,069			1,118
Total current assets ($96 and $103 related to VIEs)								981			1,039
Deferred Debits and Other Assets:
Regulatory assets		3,873			3,892			3,690			3,726
Other		92			93			110			103
Total deferred debits and other assets ($39 and $32 related to VIEs)		3,965			3,985
Total deferred debits and other assets ($36 and $35 related to VIEs)								3,800			3,829
Total assets	$	14,262		$	14,301		$	14,459		$	14,479

(millions)	March 31, 2020			December 31, 2019			March 31, 2021			December 31, 2020
CAPITALIZATION AND LIABILITIES
Common Stock - no par value, 40.3 million shares outstanding	$	3,695		$	3,695		$	4,017		$	4,017
Retained earnings		108			20			253			277
Accumulated other comprehensive loss		(3	)		(3	)		(2	)		(2	)
Total common equity		3,800			3,712			4,268			4,292
Noncontrolling interest		185			180			196			192
Total equity		3,985			3,892			4,464			4,484
Long-term debt, net		3,359			3,358			3,327			3,327
Affiliated long-term debt		230			230			230			230
Finance leases		19			20			14			15
Total long-term debt		3,608			3,608			3,571			3,572
Total capitalization		7,593			7,500			8,035			8,056
Current Liabilities:
Short-term borrowings								30			0
Securities due within one year		7			7			39			39
Accounts payable		153			245			141			178
Affiliated and related party payables		767			624			566			457
Customer deposits and customer prepayments		68			76			66			70
Taxes accrued		61			218			62			215
Interest accrued		82			88			87			95
Regulatory liabilities		281			256			280			283
Reserves for litigation and regulatory proceedings		492			492			268			208
Other		48			60			82			40
Total current liabilities		1,959			2,066			1,621			1,585
Deferred Credits and Other Liabilities:
Deferred income taxes and investment tax credits		654			629			871			858
Asset retirement obligations		494			489			603			597
Pension and other postretirement benefits		202			203			174			172
Regulatory liabilities		3,151			3,210			2,962			3,005
Affiliated liabilities		14			15			4			13
Other		195			189			189			193
Total deferred credits and other liabilities		4,710			4,735			4,803			4,838
Commitments and Contingencies (see Note 10)
Total capitalization and liabilities	$	14,262		$	14,301		$	14,459		$	14,479

	Three Months Ended March 31,					Three Months Ended March 31,
(millions)	2020		2019			2021		2020
Operating Revenue⁽¹⁾	$	672	$	(335	)	$	744	$	672
Operating Expenses:
Fuel used in electric generation⁽¹⁾		104		137			132		104
Purchased power⁽¹⁾		13		8			16		13
Gas purchased for resale⁽¹⁾		57		77			81		57
Other operations and maintenance		90		96			99		90
Other operations and maintenance - affiliated suppliers		55		48			53		55
Impairment of assets and other charges		2		271			60		2
Depreciation and amortization		118		102			121		118
Other taxes⁽¹⁾		62		69			65		62
Total operating expenses		501		808			627		501
Operating income (loss)		171		(1,143	)
Other income (expense), net		3		(5	)
Interest charges, net of allowance for borrowed funds used during construction of $2 and $-⁽¹⁾		58		73
Income (loss) before income tax expense (benefit)		116		(1,221	)
Income tax expense (benefit)		23		(118	)
Net Income (Loss) and Other Comprehensive Income (Loss)		93		(1,103	)
Operating income							117		171
Other income, net							6		3
Interest charges, net of allowance for borrowed funds used during construction of $1 and $2⁽¹⁾							55		58
Income before income tax expense							68		116
Income tax expense							13		23
Net Income and Other Comprehensive Income							55		93
Comprehensive Income Attributable to Noncontrolling Interest		5		6			4		5
Comprehensive Income (Loss) Available (Attributable) to Common Shareholder	$	88	$	(1,109	)
Comprehensive Income Available to Common Shareholder						$	51	$	88

	Three Months Ended March 31,						Three Months Ended March 31,
(millions)	2020			2019			2021			2020
Operating Activities
Net income (loss)	$	93		$	(1,103	)
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
Net income							$	55		$	93
Adjustments to reconcile net income to net cash provided by operating activities:
Impairment of assets and other charges		2			262			60			2
Provision for refunds to customers		—			985
Deferred income taxes, net		25			(416	)		13			25
Depreciation and amortization		118			104			121			118
Amortization of nuclear fuel		14			14			10			14
Other adjustments		2			(1	)		4			2
Changes in certain assets and liabilities:
Receivables		17			68			30			17
Receivables - affiliated and related party		4			—			(2	)		4
Inventories		(13	)		(23	)		17			(13	)
Prepayments		4			13			1			4
Pension and other postretirement benefits		(1	)		—			2			(1	)
Regulatory assets		(9	)		180			(6	)		(9	)
Regulatory liabilities		(48	)		202			(49	)		(48	)
Accounts payable		(20	)		(75	)		39			(20	)
Accounts payable - affiliated and related party		(8	)		3			21			(8	)
Revenue subject to refund		—			(66	)
Taxes accrued		(157	)		(106	)		(153	)		(157	)
Interest accrued		(6	)		—			(8	)		(6	)
Other assets and liabilities		3			(164	)		28			3
Net cash provided by (used in) operating activities		20			(123	)
Net cash provided by operating activities								183			20
Investing Activities
Property additions and construction expenditures		(166	)		(120	)		(215	)		(166	)
Proceeds from investments and sales of assets		26			7			3			26
Purchase of investments		(29	)		(10	)		(3	)		(29	)
Short-term investments - affiliated		6			—
Proceeds from investments - affiliated								15			6
Investment in affiliate, net		(1	)		353			(1	)		(1	)
Net cash provided by (used in) investing activities		(164	)		230
Net cash used in investing activities								(201	)		(164	)
Financing Activities
Repayment of long-term debt, including redemption premiums		—			(1,210	)
Dividend to parent		—			(29	)		(75	)		0
Contribution from parent		—			675
Money pool borrowings, net		—			273
Short-term borrowings, net		—			(73	)		30			0
Short-term borrowings - affiliated, net		151			—			88			151
Other		(1	)		—			(1	)		(1	)
Net cash provided by (used in) financing activities		150			(364	)
Net increase (decrease) in cash, restricted cash and equivalents		6			(257	)
Net cash provided by financing activities								42			150
Net increase in cash, restricted cash and equivalents								24			6
Cash, restricted cash and equivalents at beginning of period⁽¹⁾		4			377			5			4
Cash, restricted cash and equivalents at end of period⁽¹⁾	$	10		$	120		$	29		$	10
Supplemental Cash Flow Information
Significant noncash investing and financing activities:
Accrued construction expenditures	$	53		$	25		$	76		$	53
Leases⁽²⁾		3			2			0			3

	Common Stock															Common Stock
(millions)	Shares		Amount		Retained Earnings			AOCI			Noncontrolling Interest		Total Equity			Shares		Amount		Retained Earnings			AOCI			Noncontrolling Interest		Total Equity
December 31, 2018		40	$	2,860	$	1,279		$	(3	)	$	179	$	4,315
Cumulative-effect of change in accounting principle						1			(1	)				—
Total comprehensive income (loss) available (attributable) to common shareholder						(1,109	)					6		(1,103	)
Capital contribution from parent			675											675
Dividend to parent						(20	)							(20	)
March 31, 2019		40	$	3,535	$	151		$	(4	)	$	185	$	3,867

December 31, 2019		40	$	3,695	$	20		$	(3	)	$	180	$	3,892			40	$	3,695	$	20		$	(3	)	$	180	$	3,892
Total comprehensive income available to common shareholder						88						5		93							88						5		93
March 31, 2020		40	$	3,695	$	108		$	(3	)	$	185	$	3,985			40	$	3,695	$	108		$	(3	)	$	185	$	3,985

December 31, 2020																	40	$	4,017	$	277		$	(2	)	$	192	$	4,484
Total comprehensive income available to common shareholder																					51						4		55
Dividend to parent																					(75	)							(75	)
March 31, 2021																	40	$	4,017	$	253		$	(2	)	$	196	$	4,464

The following notes should be read in conjunction with the Notes to Consolidated Financial Statements appearing in DESC's Annual Report on Form 10-K for the year ended December 31, ~~2019.~~2020.

These are interim financial statements and, due to the seasonality of DESC's business and matters that may occur during the rest of the year, the amounts reported in the Consolidated Statements of Comprehensive Income ~~(Loss)~~ are not necessarily indicative of amounts expected for the full year. In the opinion of management, the information furnished herein reflects all adjustments which are necessary for a fair statement of the results for the interim periods reported, and such adjustments are of a normal recurring nature. In addition, the preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amount of revenues and expenses during the reporting period. Actual results could differ from those estimates.

Certain amounts in DESC's ~~2019~~2020 Consolidated Financial Statements and Notes have been reclassified to conform to the ~~2020~~2021 presentation for comparative purposes; however, such reclassifications did not affect DESC's net income (loss) and other comprehensive income (loss), total assets, liabilities, equity or cash flows.

DESC is a wholly-owned subsidiary of SCANA, which is a wholly-owned subsidiary of Dominion Energy.

DESC has determined that it has a controlling financial interest in each of GENCO and Fuel Company (which are considered to be VIEs) and, accordingly, DESC's Consolidated Financial Statements include, after eliminating intercompany balances and transactions, the accounts of DESC, GENCO and Fuel Company. See Note 12 to the Consolidated Financial Statements included in DESC’s Annual Report on Form 10-K for the year ended December 31, ~~2019~~2020 for a description of GENCO and Fuel Company.

~~Additionally,~~Effective January 2021, DESC purchases shared services from ~~DESS,~~DES, an affiliated VIE that provides accounting, legal, finance and certain administrative and technical services to all ~~SCANA~~Dominion Energy subsidiaries, including DESC. DESC had previously purchased such services from DESS, an affiliated VIE, that had provided such services to all SCANA subsidiaries. DESC has determined that it is not the primary beneficiary of ~~DESS~~DES as it does not have either the power to direct the activities that most significantly impact its economic performance or an obligation to absorb losses and benefits which could be significant to it. See Note 12 for amounts attributable to affiliates.

There have been no significant changes from Note 2 to the Consolidated Financial Statements in DESC's Annual Report on Form 10-K for the year ended December 31, ~~2019.~~2020.

As a result of issues generated in the ordinary course of business, DESC is involved in various regulatory matters. Certain regulatory matters may ultimately result in a loss; however, as such matters are in an initial procedural phase, involve uncertainty as to the outcome of pending reviews or orders, and/or involve significant factual issues that need to be resolved, it is not possible for DESC to estimate a range of possible loss. For regulatory matters that DESC cannot estimate, a statement to this effect is made in the description of the matter. Other matters may have progressed sufficiently through the regulatory process such that DESC is able to estimate a range of possible loss. For regulatory matters that DESC is able to reasonably estimate a range of possible losses, an estimated range of possible loss is provided, in excess of the accrued liability (if any) for such matters. Any estimated range is based on currently available information, involves elements of judgment and significant uncertainties and may not represent DESC’s maximum possible loss exposure. The circumstances of such regulatory matters will change from time to time and actual results may vary significantly from the current estimate. For current matters not specifically reported below, management does not anticipate that the outcome from such matters would have a material effect on DESC’s financial position, liquidity or results of operations.

In January 2020, GENCO filed to modify its formula rate to incorporate a mechanism to decrease or increase its income tax allowances by any excess deferred income taxes resulting from the 2017 Tax Reform Act, and future changes in tax laws. These modifications are expected to decrease charges to DESC for the power it purchases from GENCO. In April 2020, the FERC approved GENCO’s request. There have been no other changes to the 2017 Tax Reform Act matters discussed in Note 3 to the Consolidated Financial Statements in DESC’s Annual Report on Form 10-K for the year ended December 31, 2019.

Other than the following matters, there have been no significant developments regarding the pending regulatory matters disclosed in Note 3 to the Consolidated Financial Statements in DESC's Annual Report on Form 10-K for the year ended December 31, ~~2019.~~2020.

DESC’s retail electric rates include a cost of fuel component approved by the South Carolina ~~Base Rate Case~~

~~Pursuant~~Commission which may be adjusted periodically to reflect changes in the ~~SCANA Merger Approval Order,~~ price of fuel purchased by DESC. In February 2021, DESC ~~will not file an application for~~filed a ~~general rate case~~proposal with the South Carolina Commission with a requested effective date for new rates earlier than January 2021. In April 2020, the South Carolina Commission issued an order vacating the portion of the SCANA Merger Approval Order requiring that new retail electric rates be implemented by January 1, 2021.

~~In February 2020, DESC filed with the South Carolina Commission a proposal~~ to ~~decrease~~increase the total fuel cost component of retail electric rates. DESC’s proposed ~~decrease~~adjustment would ~~reduce~~increase annual base fuel component recoveries by ~~$44~~$36 million and is ~~projected~~designed to ~~return to customers the existing over-collected balance while recovering~~recover DESC’s current base fuel costs, net of the existing over-collected balance, over the 12-month period beginning with the first billing cycle of May ~~2020.~~2021. In addition, DESC proposed a decrease to its variable environmental component and an increase to its ~~variable environmental and~~ distributed energy resource components. In April ~~2020,~~2021, the South Carolina Commission approved the ~~filing~~.

DESC has approval for a DSM rider through which it recovers expenditures related to its DSM programs. In January ~~2020,~~2021, DESC ~~submitted its annual DSM programs filing to~~filed an application with the South Carolina Commission seeking approval to recover ~~$40~~$48 million of costs and net lost revenues associated with ~~DSM~~these programs, along with an incentive to invest in such programs. In April ~~2020,~~2021, the South Carolina Commission approved the filing.

DESC utilizes a pension costs rider approved by the South Carolina Commission which is designed to allow recovery of projected pension costs, including under-collected balances or net of over-collected balances, as applicable. The rider is typically reviewed for adjustment every 12 months with any resulting increase or decrease going into effect beginning with the first billing cycle in May. In February ~~2020,~~2021, DESC requested that the South Carolina Commission approve an adjustment to this rider to decrease annual revenue by ~~$11~~less than $1 million. In April ~~2020,~~2021, the South Carolina Commission approved the ~~filing~~.filing.

Rate-regulated utilities recognize in their financial statements certain revenues and expenses in different periods than do other enterprises. As a result, DESC has recorded regulatory assets and regulatory liabilities which are summarized in the following table. Except for NND Project costs and certain other unrecovered plant costs, substantially all regulatory assets are either explicitly excluded from rate base or are effectively excluded from rate base due to their being offset by related liabilities.

	March 31,		December 31,		March 31,		December 31,
(millions)	2020		2019		2021		2020
Regulatory assets:
NND Project costs⁽¹⁾	$	138	$	138	$	138	$	138
Deferred employee benefit plan costs⁽²⁾		13		13		9		9
Other unrecovered plant⁽³⁾		14		14		14		14
DSM programs⁽⁴⁾		16		17		26		29
AROs⁽⁵⁾		28		28		2		2
Cost of fuel under-collections⁽⁶⁾		3		13
Cost of fuel and purchased gas under-collections⁽⁶⁾						0		1
Other		48		48		37		36
Regulatory assets - current		260		271		226		229
NND Project costs⁽¹⁾		2,468		2,503		2,330		2,364
AROs⁽⁵⁾		305		293		317		309
Cost of reacquired debt⁽⁷⁾		255		259		241		243
Deferred employee benefit plan costs⁽²⁾		194		196		156		159
Deferred losses on interest rate derivatives⁽⁸⁾		318		305		297		308
Other unrecovered plant⁽³⁾		66		69		60		61
DSM programs⁽⁴⁾		58		54		46		46
Environmental remediation costs⁽⁹⁾		21		22		20		20
Deferred storm damage costs⁽¹⁰⁾		44		44		45		45
Deferred transmission operating costs⁽¹¹⁾		43		37		69		63
Other⁽¹²⁾		101		110		109		108
Regulatory assets - noncurrent		3,873		3,892		3,690		3,726
Total regulatory assets	$	4,133	$	4,163	$	3,916	$	3,955
Regulatory liabilities:
Monetization of guaranty settlement⁽¹³⁾	$	67	$	67	$	67	$	67
Income taxes refundable through future rates⁽¹⁴⁾		20		16		22		21
Reserve for refunds to electric utility customers⁽¹⁵⁾		138		143		127		128
Cost of fuel over-collections⁽⁶⁾		37		12
Cost of fuel and purchased gas over-collections⁽⁶⁾						53		58
Other		19		18		11		9
Regulatory liabilities - current		281		256		280		283
Monetization of guaranty settlement⁽¹³⁾		953		970		886		903
Income taxes refundable through future rates⁽¹⁴⁾		938		948		916		919
Asset removal costs⁽¹⁶⁾		558		552		571		564
Deferred gains on interest rate derivatives⁽⁸⁾		71		71		69		69
Reserve for refunds to electric utility customers⁽¹⁵⁾		623		656		505		540
Other		8		13		15		10
Regulatory liabilities - noncurrent		3,151		3,210		2,962		3,005
Total regulatory liabilities	$	3,432	$	3,466	$	3,242	$	3,288

Regulatory assets have been recorded based on the probability of their recovery. All regulatory assets represent incurred costs that may be deferred under GAAP for regulated operations. The South Carolina Commission or ~~the~~ FERC has reviewed and approved through specific orders certain of the items shown as regulatory assets. In addition, regulatory assets include, but are not limited to, certain costs which have not been specifically approved for recovery by one of these regulatory agencies, including deferred transmission operating costs that are the subject of regulatory proceedings discussed in Note ~~10.~~12 to the Consolidated Financial Statements in DESC’s Annual Report on Form 10-K for the year ended December 31, 2020. While such costs are not currently being recovered, management believes they would be allowable under existing rate-making concepts embodied in rate orders or applicable state law and expects to recover these costs through rates in future periods.

	Three Months Ended				Three Months Ended					Three Months Ended				Three Months Ended
	March 31, 2020				March 31, 2019					March 31, 2021				March 31, 2020
(millions)	Electric		Gas		Electric			Gas		Electric		Gas		Electric		Gas
Customer class:
Residential	$	252	$	79	$	(271	)	$	78	$	275	$	98	$	252	$	79
Commercial		175		33		(139	)		38		175		39		175		33
Industrial		80		17		(82	)		26		88		22		80		17
Other		30		4		10			3		33		5		30		4
Revenues from contracts with customers		537		133		(482	)		145		571		164		537		133
Other revenues		2		—		2			—		8		1		2		0
Total Operating Revenues	$	539	$	133	$	(480	)	$	145	$	579	$	165	$	539	$	133

Contract liabilities represent the obligation to transfer goods or services to a customer for which consideration has already been received from the customer. DESC had contract liability balances of ~~$4 million and $9~~$5 million at both March 31, ~~2020~~2021 and December 31, ~~2019, respectively.~~2020. During the three months ended March 31, ~~2020~~2021 and ~~2019,~~2020, DESC recognized revenue of $5$3 million and $2$5 million, respectively, from the beginning contract liability balances as DESC fulfilled its obligations to provide service to its customers. Contract liabilities are recorded in customer deposits and customer prepayments in the Consolidated Balance Sheets.

For all periods presented, DESC's authorized shares of common stock, no par value, were 50 million, of which 40.3 million were issued and outstanding, and DESC's authorized shares of preferred stock, no par value, were 20 million, of which 1,000 shares were issued and outstanding. All outstanding shares of common and preferred stock are held by SCANA.

In February 2019, DESC received an equity contribution of $675 million from its parent that was funded by Dominion Energy. DESC used these funds to redeem long-term debt. See Note 6 to the Consolidated Financial Statements in DESC’s Annual Report on Form 10-K for the year ended December 31, 2019.

At March 31, 2020, DESC’s retained earnings are below the balance established by the Federal Power Act as a reserve on earnings attributable to hydroelectric generation plants. As a result, DESC is prohibited from the payment of dividends without regulatory approval until the balance of its retained earnings increases. There have been no ~~significant~~material changes to the dividend restrictions affecting DESC described in Note 5 to the Consolidated Financial Statements in DESC’s Annual Report on Form 10-K for the year ended December 31, ~~2019.~~2020.

DESC's short-term financing is supported through its access as co-borrower to Dominion Energy’s $6.0 billion joint revolving credit facility, which can be used for working capital, as support for the combined commercial paper programs of DESC, Dominion Energy, Virginia Power ~~Dominion Energy Gas~~ and Questar Gas, and for other general corporate purposes.

At March 31, ~~2020,~~2021, DESC's share of commercial paper and letters of credit outstanding under its joint credit facility with Dominion Energy, was as follows:

(millions)

Facility Limit

Outstanding

Commercial Paper

Outstanding

Letters of Credit

Facility Limit

Outstanding

Commercial Paper

Outstanding

Letters of Credit

Joint revolving credit facility⁽¹⁾

1,000

—

1,000

In January ~~2020,~~2021, DESC and GENCO each applied to FERC for a two-year short-term borrowing authorization. In March ~~2020,~~2021, FERC granted DESC authority through March ~~2021~~2023 to issue short-term indebtedness (pursuant to Section 204 of the Federal Power Act) in amounts not to exceed $2.2 billion outstanding with maturity dates of one year or less. In addition, in March ~~2020,~~2021, FERC granted GENCO authority through March ~~2021~~2023 to issue short-term indebtedness not to exceed $200 million outstanding with maturity dates of one year or less.

DESC is obligated with respect to an aggregate of $68 million of industrial revenue bonds which are secured by letters of credit. These letters of credit expire, subject to renewal, in the fourth quarter of ~~2020.~~2021.

DESC ~~received~~has FERC approval to enter into an inter-company credit agreement ~~in April 2019~~ with Dominion Energy under which DESC may have short-term borrowings outstanding up to $900 million. At March 31, 2021 and December 31, 2020, DESC had borrowings outstanding under this credit agreement totaling ~~$486~~$443 million and $149 million, respectively, which are recorded in affiliated and related party payables in DESC’s Consolidated Balance Sheets. For both the three months ended March 31, 2021 and 2020, DESC recorded interest charges of $2 million.

~~DESC participated in a utility money pool with SCANA and another regulated subsidiary of SCANA through April 2019.~~ Fuel Company and GENCO ~~remain~~participated in ~~the~~a SCANA utility money ~~pool.~~pool until January 2021, when that utility money pool was closed. Money pool borrowings and investments ~~bear~~bore interest at short-term market rates. For the three months ended March 31, 2021 and 2020 DESC recorded interest income from money pool transactions of less than $1 million and $1 million, respectively, and for the same period DESC recorded interest expense from money pool transactions of less than $1 ~~million. For the three months ended March 31, 2019, DESC recorded interest income from money pool transactions of $3~~ million and ~~for the same period~~$1 million, respectively. At December 31, 2020, DESC ~~recorded interest expense from money pool transactions of $3 million. Fuel Company~~ had outstanding money pool borrowings due to an affiliate of ~~$239~~$206 million and ~~GENCO had~~ investments due from an affiliate of ~~$3 million at March 31, 2020. At December 31, 2019, Fuel Company had outstanding money pool borrowings due to an affiliate of $219 million and GENCO had investments due from an affiliate of $9~~$15 million. On its Consolidated Balance ~~Sheets,~~Sheet, DESC includes money pool borrowings within affiliated and related party payables and money pool investments within affiliated and related party receivables.

DESC’s effective tax rate for the three months ended March 31, 2021 is 19.5% compared to 19.9% for the three months ended March 31, 2020.

DESC has recorded an estimate of excess deferred income tax amortization in ~~2020.~~2021. The reversal of these excess deferred income taxes will impact the effective tax rate and rates charged to customers. See Note 3 to the Consolidated Financial Statements in DESC’s Annual Report on Form 10-K for the year ended December 31, ~~2019~~2020 for more information.

DESC’s effective tax rate for the three months ended March 31, 2020 is 19.9% compared to 9.7% for the three months ended March 31, 2019. Variances in the effective tax rate are primarily driven by charges resulting from the SCANA Combination. In connection with the SCANA Merger Approval Order, Dominion Energy committed to forgo, or limit, the recovery of certain income tax-related regulatory assets associated with the NND Project. DESC's 2019 effective tax rate reflects income tax expense of $198 million in satisfaction of this commitment. Also in the first quarter 2019, DESC’s unrecognized tax benefits increased by $51 million and income tax expense increased by $40 million related to a state income tax position taken in prior years.

In March 2020, the CARES Act was enacted which includes several significant business tax provisions that modify or temporarily suspend certain provisions of the 2017 Tax Reform Act. The CARES Act provisions are intended to improve cash flow and liquidity by, among other things, providing a temporary five-year carryback for certain net operating losses, accelerating the refund of previously generated corporate alternative minimum tax credits, and temporarily loosening the business interest limitation to 50% of adjusted taxable income for certain businesses. While DESC intends to utilize the income tax provisions of the CARES Act to accelerate the recognition of certain tax attributes, where applicable, they are not expected to provide a material benefit.

As of March 31, ~~2020,~~2021, there have been no ~~other~~ material changes in DESC’s unrecognized tax benefits. See Note 7 to the Consolidated Financial Statements in DESC's Annual Report on Form 10-K for the year ended December 31, ~~2019~~2020 for a discussion of these unrecognized tax benefits.

DESC’s accounting policies, objectives, and strategies for using derivative instruments are discussed in Note 2 in the Consolidated Financial Statements in DESC’s Annual Report on Form 10-K for the year ended December 31, ~~2019.~~2020. See Note 8 for further information about fair value measurements and associated valuation methods for derivatives.

Derivative assets and liabilities are presented gross on the Consolidated Balance Sheets. DESC’s derivative contracts include over-the-counter transactions. Over-the-counter contracts are bilateral contracts that are transacted directly with a third party. Certain over-the-counter contracts contain contractual rights of setoff through master netting arrangements and contract default provisions. In addition, the contracts are subject to conditional rights of setoff through counterparty nonperformance, insolvency, or other conditions.

In general, most over-the-counter transactions are subject to collateral requirements. Types of collateral for over-the-counter contracts include cash, letters of credit, and, in some cases, other forms of security, none of which are subject to restrictions. Cash collateral, ~~is used~~as presented in the table below, is used to offset derivative assets and liabilities.

All of DESC’s derivative instruments contain credit-related contingent provisions. These provisions require DESC to provide collateral upon the occurrence of specific events, primarily a credit rating downgrade. If the credit-related contingent features underlying the instruments that are in a liability position and not fully collateralized with cash were fully triggered as of March 31, 2021 and December 31, 2020, DESC would have been required to post $7 million and $10 million, respectively, of additional collateral to its counterparties. The collateral that would be required to be posted includes the impacts of any amounts already posted for derivatives per contractual terms. DESC had posted $4$1 million of collateral at ~~March~~December 31, 2020 related to derivatives with credit-related contingent provisions that are in a liability position and not fully collateralized with cash. NaN such collateral was posted at DESC at March 31, 2021. The aggregate fair value of all derivative instruments with credit-related contingent provisions that are in a liability position and not fully collateralized with cash was ~~$14~~$7 million and $11 million at March 31, ~~2020. DESC’s derivatives with credit related contingent provisions that were in a liability position were fully collateralized with cash at~~2021 and December ~~31,2019.~~31, 2020, respectively.

The table below presents derivative balances by type of financial instrument, if the gross amounts recognized in the Consolidated Balance Sheets were netted with derivative instruments and cash collateral received or paid:

	March 31, 2020								December 31, 2019								March 31, 2021								December 31, 2020
	Gross Amounts Not Offset in the Consolidated Balance Sheet								Gross Amounts Not Offset in the Consolidated Balance Sheet								Gross Amounts Not Offset in the Consolidated Balance Sheet								Gross Amounts Not Offset in the Consolidated Balance Sheet
(millions)	Gross Liabilities Presented in the Consolidated Balance Sheet		Financial Instruments		Cash Collateral Paid		Net Amounts		Gross Liabilities Presented in the Consolidated Balance Sheet		Financial Instruments		Cash Collateral Paid		Net Amounts		Gross Liabilities Presented in the Consolidated Balance Sheet		Financial Instruments		Cash Collateral Paid		Net Amounts		Gross Liabilities Presented in the Consolidated Balance Sheet		Financial Instruments		Cash Collateral Paid		Net Amounts
Interest rate contracts:
Over-the-counter	$	33	$	—	$	23	$	10	$	19	$	—	$	19	$	—	$	18	$	0	$	11	$	7	$	27	$	0	$	17	$	10
Total derivatives	$	33	$	—	$	23	$	10	$	19	$	—	$	19	$	—	$	18	$	0	$	11	$	7	$	27	$	0	$	17	$	10

The following table presents the volume of derivative activity at March 31, ~~2020.~~2021. These volumes are based on open derivative positions and represent the combined absolute value of their long and short positions.

The following tables present the fair values of derivatives and where they are presented in the Consolidated Balance Sheets:

(millions)	Fair Value - Derivatives under Hedge Accounting		Fair Value - Derivatives not under Hedge Accounting		Total Fair Value		Fair Value - Derivatives under Hedge Accounting		Fair Value - Derivatives not under Hedge Accounting		Total Fair Value
At March 31, 2020
At March 31, 2021
LIABILITIES
Current Liabilities
Interest rate	$	1	$	1	$	2	$	1	$	1	$	2
Total current derivative liabilities⁽¹⁾		1		1		2		1		1		2
Noncurrent Liabilities
Interest rate		18		13		31		10		6		16
Total noncurrent derivative liabilities⁽²⁾		18		13		31		10		6		16
Total derivative liabilities	$	19	$	14	$	33	$	11	$	7	$	18
At December 31, 2019
At December 31, 2020
LIABILITIES
Current Liabilities
Interest rate	$	1	$	1	$	2	$	1	$	1	$	2
Total current derivative liabilities⁽¹⁾		1		1		2		1		1		2
Noncurrent Liabilities
Interest rate		11		6		17		15		10		25
Total noncurrent derivative liabilities⁽²⁾		11		6		17		15		10		25
Total derivative liabilities	$	12	$	7	$	19	$	16	$	11	$	27

The following tables present the gains and losses on derivatives, as well as where the associated activity is presented in ~~its~~the Consolidated Balance Sheets and Statements of Comprehensive Income (Loss):

(millions)	Gain (loss) Reclassified from Deferred Accounts into Income		Increase (Decrease) in Derivatives Subject to Regulatory Treatment⁽¹⁾			Increase (Decrease) in Derivatives Subject to Regulatory Treatment⁽¹⁾
Three Months Ended March 31, 2021
Derivative type and location of gains (losses):
Interest rate⁽²⁾						$	7
Total						$	7
Three Months Ended March 31, 2020
Derivative type and location of gains (losses):
Interest rate⁽²⁾	$	—	$	(6	)	$	(6	)
Total	$	—	$	(6	)	$	(6	)
Three Months Ended March 31, 2019
Derivative type and location of gains (losses):
Interest rate⁽²⁾	$	—	$	(2	)
Total	$	—	$	(2	)

DESC’s fair value measurements are made in accordance with the policies discussed in Note 9 to the Consolidated Financial Statements in DESC’s Annual Report on Form 10-K for the year ended December 31, ~~2019.~~2020. See Note 7 in this report for further information about ~~the~~ DESC’s derivatives and hedge accounting activities.

The following table presents DESC’s liabilities that are measured at fair value on a recurring basis for each hierarchy level, including both current and noncurrent portions:

(millions)	Level 1		Level 2		Level 3		Total		Level 1		Level 2		Level 3		Total
At March 31, 2020
At March 31, 2021
Liabilities
Interest rate	$	—	$	33	$	—	$	33	$	0	$	18	$	0	$	18
Total liabilities	$	—	$	33	$	—	$	33	$	0	$	18	$	0	$	18
At December 31, 2019
At December 31, 2020
Liabilities
Interest rate	$	—	$	19	$	—	$	19	$	0	$	27	$	0	$	27
Total liabilities	$	—	$	19	$	—	$	19	$	0	$	27	$	0	$	27

Substantially all of DESC’s financial instruments are recorded at fair value, with the exception of the instruments described below, which are reported at historical cost. Estimated fair values have been determined using available market information and valuation methodologies considered appropriate by management. The carrying amount of financial instruments classified within current assets and current liabilities are representative of fair value because of the short-term nature of these instruments. For financial instruments that are not recorded at fair value, the carrying amounts and estimated fair values are as follows:

	March 31, 2020				December 31, 2019				March 31, 2021				December 31, 2020
(millions)	Carrying Amount		Estimated Fair Value⁽¹⁾		Carrying Amount		Estimated Fair Value⁽¹⁾		Carrying Amount		Estimated Fair Value⁽¹⁾		Carrying Amount		Estimated Fair Value⁽¹⁾
Long-term debt⁽²⁾	$	3,359	$	4,060	$	3,358	$	4,262	$	3,360	$	4,299	$	3,360	$	4,748
Affiliated long-term debt		230		230		230		230		230		230		230		230

(2) Carrying amount includes current portions included in securities due within one year and amounts which represent the unamortized debt issuance costs and discount or premium.

(millions)	Pension Benefits						Other Postretirement Benefits				Pension Benefits						Other Postretirement Benefits
Three Months Ended March 31,	2020			2019			2020		2019		2021			2020			2021		2020
Service cost	$	3		$	4		$	1	$	1	$	3		$	3		$	1	$	1
Interest cost		6			8			2		2		5			6			1		2
Expected return on assets		(11	)		(10	)		—		—		(12	)		(11	)		0		0
Amortization of actuarial losses		2			4			—		—		2			2			0		0
Net periodic benefit cost	$	—		$	6		$	3	$	3
Net periodic benefit cost (credit)											$	(2	)	$	0		$	2	$	3

~~No significant contribution~~During the three months ended March 31, 2021, DESC made no contributions to ~~the~~its pension trust ~~is expected for the remainder of 2020 based on current market conditions~~ and ~~assumptions, nor is a limitation on benefit payments expected~~does not expect to ~~apply.~~make any such contributions in 2021. DESC recovers current pension costs through either a rate rider that may be adjusted annually for retail electric operations or through cost of service rates for gas operations.

As a result of issues generated in the ordinary course of business, DESC is involved in legal proceedings before various courts and is periodically subject to governmental examinations (including by regulatory authorities), inquiries and investigations. Certain legal proceedings and governmental examinations involve demands for unspecified amounts of damages, are in an initial procedural phase, involve uncertainty as to the outcome of pending appeals or motions, or involve significant factual issues that need to be resolved, such that it is not possible for DESC to estimate a range of possible loss. For such matters that DESC cannot estimate, a statement to this effect is made in the description of the matter. Other matters may have progressed sufficiently through the litigation or investigative processes such that DESC is able to estimate a range of possible loss. For legal proceedings and governmental examinations that DESC is able to reasonably estimate a range of possible losses, an estimated range of possible loss is provided, in excess of the accrued liability (if any) for such matters. Any accrued liability is recorded on a gross basis with a receivable also recorded for any probable insurance recoveries. Estimated ranges of loss are inclusive of legal fees and net of any anticipated insurance recoveries. Any estimated range is based on currently available information and involves elements of judgment and significant uncertainties. Any estimated range of possible loss may not represent DESC’s maximum possible loss exposure. The circumstances of such legal proceedings and governmental examinations will change from time to time and actual results may vary significantly from the current estimate. For current proceedings not specifically reported below, management does not anticipate that the liabilities, if any, arising from such proceedings would have a material effect on DESC’s financial position, liquidity or results of operations.

DESC is subject to costs resulting from a number of federal, state and local laws and regulations designed to protect human health and the environment. These laws and regulations affect future planning and existing operations. They can result in increased capital, operating and other costs as a result of compliance, remediation, containment and monitoring obligations.

From a regulatory perspective, DESC and GENCO continually monitor and evaluate their current and projected emission levels and strive to comply with all state and federal regulations regarding those emissions. DESC and GENCO participate in the SO₂and NO_X emission allowance programs with respect to coal plant emissions and also have constructed additional pollution control equipment at their coal-fired electric generating plants. These actions are expected to address many of the rules and regulations discussed herein.

The CAA, as amended, is a comprehensive program utilizing a broad range of regulatory tools to protect and preserve the nation's air quality. At a minimum, states are required to establish regulatory programs to ~~address all~~meet applicable requirements of the CAA. However, states may choose to develop regulatory programs that are more restrictive. Many of DESC’s facilities are subject to the CAA’s permitting and other requirements.

~~In February 2019, the EPA published a proposed rule to reverse its previous finding that it is appropriate and necessary to regulate hazardous air pollutant emissions from~~ ~~coal- and oil-fired electric generating units~~. In April 2020, the EPA finalized its reconsideration and issued a final rule. The final rule is consistent with the EPA’s February 2019 proposal, and determines that it is not appropriate and necessary to regulate mercury and hazardous air pollutant emissions from coal- and oil-fired electric generating units. The final rule also states that the MATS rule remains in place and the emissions standards for affected coal- and oil-fired electric generating units will not change. The effective date of the action will be 60 days after publication in the Federal Register. ~~DESC is complying with the applicable requirements of the rule and does not expect any impacts to its operations.~~

The EPA published final non-attainment designations for the October 2015 ozone standard in June 2018. States have until August 2021 to develop plans to address the new standard. Until the states have developed implementation plans for the standard, DESC is unable to predict whether or to what extent the new rules will ultimately require additional controls. The expenditures required to implement additional controls could have a material impact on DESC’s results of operations and cash flows.

In July 2019, the EPA published the final rule informally referred to as the ACE Rule, as a replacement for the Clean Power Plan. The ACE Rule ~~applies to~~regulated GHG emissions from existing coal-fired power ~~plants. The final rule includes unit-specific performance standards based on~~plants pursuant to Section 111(d) of the ~~degree of emission reduction levels achievable from unit efficiency improvements to be determined by the permitting agency. The ACE Rule requires~~CAA and required states to develop plans by July 2022 establishing unit-specific performance standards for existing coal-fired power plants. In January 2021, the U.S. Court of Appeals for the D.C. Circuit vacated the ACE Rule and remanded it to ~~implement these performance standards. These state plans must be approved by~~the EPA. This decision would take effect upon issuance of the court’s mandate. In March 2021, the court issued a partial mandate vacating and remanding all parts of the ACE Rule except for the portion of the ACE Rule that repealed the Clean Power Plan. While the EPA ~~by January 2024. While~~has stated its intention to replace the ~~impacts of~~ACE Rule, it is unknown at this ~~rule could be material to~~time if or how the EPA will issue a replacement for the ACE Rule and how that replacement will affect DESC’s ~~results of~~ operations, financial condition and/or cash ~~flows, the existing regulatory framework in South Carolina provides rate recovery mechanisms that could substantially mitigate any such impacts for DESC.~~

In August 2016, the EPA issued a draft rule proposing to reaffirm that a source’s obligation to obtain a PSD or Title V permit for GHGs is triggered only if such permitting requirements are first triggered by non-GHG, or conventional, pollutants that are regulated by the New Source Review program, and ~~to set~~exceed a significant emissions rate atof 75,000 tons per year of ~~CO2~~CO₂ equivalent ~~emissions under which a source would not be required to apply BACT for its GHG~~ emissions. Until the EPA ultimately takes final action on this rulemaking, DESC cannot predict the impact to its results of operations, financial condition and/or cash flows.

In December 2018, the EPA proposed revised Standards of Performance for Greenhouse Gas Emissions from New, Modified, and Reconstructed Stationary Sources. The proposed rule would amend the previous determination that the best system of emission reduction for newly constructed coal-fired steam generating units is no longer partial carbon capture and storage. Instead, the proposed revised best system of emission reduction for this source category is the most efficient demonstrated steam cycle (e.g., supercritical steam conditions for large units and subcritical steam conditions for small units) in combination with ~~the~~ best operating practices.

In August 2012, the EPA issued an NSPS impacting new and modified facilities in the natural gas production and gathering sectors and made revisions to the NSPS for natural gas processing and transmission facilities. These rules establish equipment performance specifications and emissions standards for control of VOC emissions for natural gas production wells, tanks, pneumatic controllers, and compressors in the upstream sector. In June 2016, the EPA issued another NSPS regulation, for the oil and natural gas sector, to regulate methane and VOC emissions from new and modified facilities in transmission and storage, gathering and boosting, production and processing facilities. All projects which commenced construction after September 2015 are required to comply with this regulation. In October 2018,January 2021, the EPA published a final rule affirming that fossil fuel-fired electric generating units meet the requirement that a source category “significantly contribute” to endangering air pollution for the purposes of regulating GHG emissions from new, modified and reconstructed stationary sources. The January 2021 rule also established a threshold for the “significant contribution” threshold that would have meant that no other source category, such as oil and gas facilities, petroleum refineries, and boilers, would meet that requirement at this time. In April 2021, the U.S. Court of Appeals for the D.C. Circuit granted an unopposed motion by the EPA to vacate and remand the January 2021 rule. The proposed ~~rule reconsidering and amending portions of the 2016 rule, including but not limited~~revision to the ~~fugitive emissions requirements at well sites and compressor stations. The amended portions of the 2016 rule were effective immediately upon publication.~~performance standards for coal-fired steam generating units remains pending. Until the ~~proposed rule regarding reconsideration is~~EPA ultimately takes final action on this rulemaking, DESC ~~is implementing~~cannot predict the ~~2016 regulation. DESC is still evaluating whether potential impacts on~~impact to its results of operations, financial condition and/or cash ~~flows related to this matter will be material.~~flows.

The CWA, as amended, is a comprehensive program requiring a broad range of regulatory tools including a permit program to authorize and regulate discharges to surface waters with strong enforcement mechanisms. DESC must comply with applicable aspects of the CWA programs at its operating facilities.

In October 2014, the final regulations under Section 316(b) of the CWA that govern existing facilities and new units at existing facilities that employ a cooling water intake structure and that have flow levels exceeding a minimum threshold became effective. The rule establishes a national standard for impingement based on seven compliance options, but forgoes the creation of a single technology standard for entrainment. Instead, the EPA has delegated entrainment technology decisions to state regulators. State regulators are to make case-by-case entrainment technology determinations after an examination of five mandatory facility-specific factors, including a social cost-benefit test, and six optional facility-specific factors. The rule governs all electric generating stations with water withdrawals above 2 MGD, with a heightened entrainment analysis for those facilities over 125 MGD. DESC has 5 facilities that are subject to the final regulations. DESC is also working with the EPA and state regulatory agencies to assess the applicability of Section 316(b) to 5 hydroelectric facilities. DESC anticipates that it may have to install impingement control technologies at certain of these stations that have once-through cooling systems. DESC is currently evaluating the need or potential for entrainment controls under the final rule as these decisions will be made on a case-by-case basis after a thorough review of detailed biological, technology, cost and benefit studies. DESC is conducting studies and implementing plans as required by the rule to determine appropriate intake structure modifications at certain facilities to ensure compliance with this rule. While the impacts of this rule could be material to DESC’s results of operations, financial condition and/or cash flows, the existing regulatory framework in South Carolina provides rate recovery mechanisms that could substantially mitigate any such impacts for DESC.

In September 2015, the EPA released a final rule to revise the ELG Rule. The final rule ~~establishes~~established updated standards for wastewater discharges that apply primarily at coal and oil steam generating stations. Affected facilities are required to convert from wet to dry or closed cycle coal ash management, improve existing wastewater treatment systems and/or install new wastewater treatment technologies in order to meet the new discharge limits. In April 2017, the EPA granted two separate petitions for reconsideration of the final ELG Rule and stayed future compliance dates in the rule. Also in April 2017, the U.S. Court of Appeals for the Fifth Circuit granted the EPA’s request for a stay of the pending consolidated litigation challenging the rule while the EPA addresses the petitions for reconsideration. In September 2017, the EPA signed a rule to postpone the earliest compliance dates for certain waste streams regulations in the final ELG Rule from November 2018 to November 2020; however, the latest date for compliance for these regulations ~~remains~~was December 2023. In October 2020, the EPA released the final rule that extends the latest dates for compliance. Individual facilities’ compliance dates will vary based on circumstances and the determination by state regulators and may range from 2021 to 2028. While the impacts of this rule could be material to DESC’s results of operations, financial condition and/or cash flows, as DESC expects that wastewater treatment technology retrofits ~~will be required~~and modifications to the bottom ash handling systems at the Williams and Wateree generating stations will be required, the existing regulatory framework in South Carolina provides rate recovery mechanisms that could substantially mitigate any such impacts for DESC.

In ~~December~~November 2019, a new CUA was established in the ~~EPA released proposed revisions~~counties surrounding the Cope Generating Station (Western Capacity Use Area) under the South Carolina Groundwater Use and Reporting Regulation. Under the regulation any groundwater well in a CUA that withdraws above three million gallons per month must be permitted. The Cope Generating Station is located within this new Western Capacity Use Area. Cope has been using four deep groundwater wells for cooling water and other house loads since 1996. Prior to designation of the ~~ELG Rule that, if adopted, could extend~~new Western Capacity Use Area, the ~~deadlines for compliance with certain standards~~wells at ~~several facilities.~~Cope Station were only required to be registered not permitted. As a result of this designation, Cope will need to restore the surface water equipment to operable status to reduce reliance on groundwater wells. This includes completion of 316(b) requirements, (including SCDHEC BACT determination and modification of the station national pollutant discharge elimination system permit) and extensive inspection, repair and/or replacement of the associated surface water withdrawal equipment which has been idle since 1996. While the impacts of this rule ~~could be~~change are material to DESC’s results of operations, financial condition and/or cash flows, the existing regulatory ~~frameworks~~framework in South Carolina ~~provide~~provides rate recovery mechanisms that could substantially mitigate any such impacts for ~~the regulated electric utilities.~~DESC.

The operations of DESC are subject to a variety of state and federal laws and regulations governing the management and disposal of solid and hazardous waste, and release of hazardous substances associated with current and/or historical operations. The CERCLA, as amended, and similar state laws, may impose joint, several and strict liability for cleanup on potentially responsible parties who owned, operated or arranged for disposal at facilities affected by a release of hazardous substances. In addition, many states have created programs to incentivize voluntary remediation of sites where historical releases of hazardous substances are identified and property owners or responsible parties decide to initiate cleanups.

From time to time, DESC may be identified as a potentially responsible party in connection with the alleged release of hazardous substances or wastes at a site. Under applicable federal and state laws, DESC could be responsible for costs associated with the investigation or remediation of impacted sites, or subject to contribution claims by other responsible parties for their costs incurred at such sites. DESC also may identify, evaluate and remediate other potentially impacted sites under voluntary state programs. Remediation costs may be subject to reimbursement under DESC’s insurance policies, rate recovery mechanisms, or both. Except as described below, DESC does not believe these matters will have a material effect on results of operations, financial condition and/or cash flows.

DESC has 4 decommissioned MGP sites in South Carolina that are in various states of investigation, remediation and monitoring under work plans approved by, or under review by, the SCDHEC or the EPA. DESC anticipates that activities at these sites will continue through 2025 at an estimated cost of ~~$10~~ $9million. In ~~September 2018, DESC submitted an updated remediation work plan~~addition, for one site, an updated work plan submitted to SCDHEC ~~which if approved,~~in September 2018, would increase costs by approximately ~~$8 million.~~$11 million if approved by federal and state agencies. In September 2020, this plan was submitted to the Army Corps of Engineers. DESC expects to recover costs arising from the remediation work at all four sites through rate recovery mechanisms and as of March 31, ~~2020,~~2021, deferred amounts, net of amounts previously recovered through rates and insurance settlements, totaled ~~$23~~$22 million and are included in regulatory assets.

In April 2015, the EPA enacted a final rule regulating CCR landfills, existing ash ponds that still receive and manage CCRs, and inactive ash ponds that do not receive, but still store, CCRs. DESC currently has inactive and existing CCR ponds and CCR landfills subject to the final rule at 3 different facilities. This rule created a legal obligation for DESC to retrofit or close all of its inactive and existing ash ponds over a certain period of time, as well as perform required monitoring, corrective action, and post-closure care activities as necessary.

In December 2016, legislation was enacted that creates a framework for EPA- approved state CCR permit programs. In August 2017, the EPA issued interim guidance outlining the framework for state CCR program approval. The EPA has enforcement authority until state programs are approved. The EPA and states with approved programs both will have authority to enforce CCR requirements under their respective rules and programs. In September 2017, the EPA agreed to reconsider portions of the CCR rule in response to two petitions for reconsideration. In March 2018, the EPA proposed certain changes to the CCR rule related to issues remanded as part of the pending litigation and other issues the EPA is reconsidering. Several of the proposed changes would allow states with approved CCR permit programs additional flexibility in implementing their programs. In July 2018, the EPA promulgated the first phase of changes to the CCR rule. Until all phases of the CCR rule are promulgated, DESC cannot forecast potential incremental impacts or costs related to existing coal ash sites in connection with future implementation of the 2016 CCR legislation and reconsideration of the CCR rule. In August 2018, the U.S. Court of Appeals for the D.C. Circuit issued its decision in the pending challenges of the CCR rule, vacating and remanding to the EPA three provisions of the rule. Until ~~regulatory action~~this matter is ~~taken to incorporate~~resolved and all phases of the ~~U.S. Court of Appeals for the D.C. Circuit’s decision,~~CCR rule are promulgated, DESC is unable to ~~make an~~precisely estimate ~~of the~~ potential ~~financial statement~~incremental impacts ~~associated with any future changes~~or costs related to ~~the CCR rule~~existing coal ash sites in connection with future implementation of the ~~court’s remand.~~

final CCR rule. While such amounts may be material to DESC’s results of operations, financial condition and/or cash flows, the existing regulatory framework in South Carolina provides rate recovery mechanisms that could substantially mitigate any such impacts.

A description of events and circumstances leading up to DESC's abandonment of the NND Project and subsequent regulatory, legislative, legal and investigative proceedings, as well as related impairments of NND Project and other costs are described in Note 12 to the Consolidated Financial Statements in DESC's Annual Report on Form 10-K for the year ended December 31, ~~2019.~~

In accordance with the terms of the South Carolina Commission's SCANA Merger Approval Order, DESC adopted the Plan-B Levelized Customer Benefits Plan, effective February 2019, whereby the average bill for a DESC residential electric customer approximates that which resulted from the legislatively-mandated temporary reduction that had been put into effect by the South Carolina Commission in August 2018. DESC also recorded a significant impairment charge in the fourth quarter of 2018, which charge resulted from its conclusion that NND Project capital costs exceeding the amount established in the SCANA Merger Approval Order were probable of loss, regardless of whether the SCANA Combination was completed. In addition, in the first quarter of 2019, DESC recorded the following charges and liabilities which arose from or are related to provisions in the SCANA Merger Approval Order.

Further, except for rate adjustments for fuel and environmental costs, DSM costs, and other rates routinely adjusted on an annual or biannual basis, DESC will freeze retail electric base rates at current levels until January 1, 2021. As discussed in Note 2, ~~in April 2020, the South Carolina Commission~~ ~~issued an order vacating the portion of the SCANA Merger Approval Order requiring that new retail electric rates be implemented by January 1, 2021~~

The South Carolina Commission order also approved the removal of DESC's investment in certain transmission assets that have not been abandoned from BLRA capital costs. As of March 31, 2020, such investment in these assets included $345 million within utility plant, net and $43 million within regulatory assets, which amount represents certain deferred operating costs. The South Carolina Commission approved deferral of these operating costs related to the investment until recovery of the transmission capital costs and associated deferred operating costs is addressed in a future rate proceeding. DESC believes these transmission capital and deferred operating costs are probable of recovery; however, if the South Carolina Commission were to disallow recovery of or a reasonable return on all or a portion of them, an impairment charge equal to the disallowed costs may be required.2020.

The following describes certain legal proceedings involving DESC relating to events occurring before closing of the SCANA Combination. No reference to, or disclosure of, any proceeding, item or matter described below shall be construed as an admission or indication that such proceeding, item or matter is material. For certain of these matters, and unless otherwise noted therein, DESC is unable to estimate a reasonable range of possible loss and the related financial statement impacts, but for any such matter there could be a material impact to its results of operations, financial condition and/or cash flows. For the matters for which DESC is able to reasonably estimate, ~~a probable loss,~~ the Consolidated Balance Sheets at ~~both~~ March 31, ~~2020~~2021 and December 31, ~~2019~~2020 include reserves of ~~$492~~$268 million and $208 million, respectively, and insurance receivables at both dates of $6$8 million, included within other receivables. During the three months ended March 31, ~~2019, the~~2021, DESC’s Consolidated Statements of ~~Comprehensive~~ Income ~~(Loss) includes~~include charges of ~~$166~~$60 million ($~~125~~45 million after-tax), included within impairment of assets and other charges.

In May 2018, a consolidated complaint against DESC, SCANA and the State of South Carolina was filed in the State Court of Common Pleas in Hampton County, South Carolina (the DESC Ratepayer Case). ~~In September 2018, the court certified this case as a class action.~~ The plaintiffs ~~allege,~~alleged, among other things, that DESC was negligent and unjustly enriched, breached alleged fiduciary and contractual duties and committed fraud and misrepresentation in failing to properly manage the NND Project, and that DESC committed unfair trade practices and violated state anti-trust laws. The plaintiffs sought a declaratory judgment that DESC may not charge its customers for any past or continuing costs of the NND Project, sought to have SCANA and DESC’s assets frozen and all monies recovered from Toshiba and other sources be placed in a constructive trust for the benefit of ratepayers and sought specific performance of the alleged implied contract to construct the NND Project.

In December 2018, the State Court of Common Pleas in Hampton County entered an order granting preliminary approval of a class action settlement. The court entered an order granting final approval of the settlement ~~and a stay of pre-trial proceedings~~ in ~~the DESC Ratepayer Case.~~June 2019, which became effective in July 2019. The settlement agreement, contingent upon the closing of the SCANA Combination, provided that SCANA and DESC ~~would~~ establish an escrow account and proceeds from the escrow account would be distributed to the ~~class members,~~plaintiffs, after payment of certain taxes, attorneys' fees and other expenses and administrative costs. The escrow account would include (1) up to $2.0 billion, net of a credit of up to $2.0 billion in future electric bill relief, which would inure to the benefit of the escrow account in favor of class members over a period of time established by the South Carolina Commission in its order related to matters before the South Carolina Commission related to the NND Project, (2) a cash payment of $115 million and (3) the transfer of certain DESC-owned real estate or sales proceeds from the sale of such properties, which counsel for the ~~DESC Ratepayer Class estimate~~plaintiffs estimated to have an aggregate value between $60 million and $85 million. At the closing of the SCANA Combination, SCANA and DESC funded the cash payment portion of the escrow account. ~~The court held a fairness hearing on the settlement in May 2019. In June 2019, the court entered an order granting final approval of the settlement, which order became effective July 2019.~~ In July 2019, DESC transferred $117 million representing the cash payment, plus accrued interest, to the plaintiffs. ~~In addition,~~Through August 2020, property, plant and equipment with a net recorded value of ~~$42~~$22 million ~~is in the process of being~~had been transferred to the plaintiffs in coordination with the court-appointed real estate trustee to satisfy the settlement agreement. In September 2020, the court entered an order approving a final resolution of the transfer of real estate or sales proceeds with a cash contribution of $38.5 million by DESC and the conveyance of property, plant and equipment with a net recorded value of $3 million, which was completed by DESC in October 2020.

In September 2017, a purported class action was filed by Santee Cooper ratepayers against Santee Cooper, DESC, Palmetto Electric Cooperative, Inc. and Central Electric Power Cooperative, Inc. in the State Court of Common Pleas in Hampton County, South Carolina (the Santee Cooper Ratepayer Case). The allegations ~~are~~were substantially similar to those in the DESC Ratepayer Case. The plaintiffs seek a declaratory judgment that the defendants may not charge the purported class for reimbursement for past or future costs of the NND Project. In March 2018, the plaintiffs filed an amended complaint including as additional named defendants certain then current and former directors of Santee Cooper and SCANA. In June 2018, Santee Cooper filed a Notice of Petition for Original Jurisdiction with the Supreme Court of South Carolina which was denied. In December 2018, Santee Cooper filed its answer to the plaintiffs' fourth amended complaint and filed cross claims against DESC. In October 2019, Santee Cooper voluntarily consented to stay its cross claims against DESC pending the outcome of the trial of the underlying case. In November 2019, DESC removed the case to the U.S. District Court for the District of South Carolina. In December 2019, the plaintiffs and Santee Cooper filed a motion to remand the case to state court. In January 2020, the case was remanded to state court. In March 2020, the parties executed a settlement agreement relating to this matter as well as the Luquire Case and the Glibowski Case described below. The settlement agreement ~~provides~~provided that Dominion Energy and Santee Cooper ~~will~~ establish a fund for the benefit of class members in the amount of $520 million, of which ~~DESC’s~~Dominion Energy’s portion iswas $320 million of shares of Dominion Energy common stock. ~~Also in March~~In July 2020, the court ~~granted preliminary~~issued a final approval ~~for~~of the settlement agreement. ~~This case is pending.~~In September 2020, Dominion Energy issued $322 million of shares of Dominion Energy common stock to satisfy its obligation under the settlement agreement, including interest charges.

In July 2019, a similar purported class action was filed by certain Santee Cooper ratepayers against DESC, SCANA, Dominion Energy and former directors and officers of SCANA in the State Court of Common Pleas in Orangeburg, South Carolina (the Luquire Case). In August 2019, DESC, SCANA and Dominion Energy were voluntarily dismissed from the case. The claims ~~are~~were similar to the Santee Cooper Ratepayer Case. In March 2020, the parties executed a settlement agreement as described above relating to this matter as well as the Santee Cooper Ratepayer Case and the Glibowski Case. This case ~~is pending.~~was dismissed as part of the Santee Cooper Ratepayer Case settlement described above.

In January 2018, a purported class action was filed, and subsequently amended, against SCANA, DESC and certain former executive officers in the U.S. District Court for the District of South Carolina (the Glibowski Case). The plaintiff ~~alleges,~~alleged, among other things, that SCANA, DESC and the individual defendants participated in an unlawful racketeering enterprise in violation of RICO and conspired to violate RICO by fraudulently inflating utility bills to generate unlawful proceeds. The DESC Ratepayer Class Action settlement described previously contemplates dismissal of claims by DESC ratepayers in this case against DESC, SCANA and their officers. In August 2019, the individual defendants filed motions to dismiss. In March 2020, the parties executed a settlement agreement as described above relating to this matter as well as the Santee Cooper Ratepayer Case and the Luquire Case. This case ~~is pending.~~was dismissed as part of the Santee Cooper Ratepayer Case settlement described above.

In February 2018, a purported class action was filed against Dominion Energy and certain former directors of SCANA and DESC in the State Court of Common Pleas in Richland County, South Carolina (the Metzler Lawsuit). The plaintiff alleges, among other things, that defendants violated their fiduciary duties to shareholders by executing a merger agreement that would unfairly deprive plaintiffs of the true value of their SCANA stock, and that Dominion Energy aided and abetted these actions. Among other remedies, the plaintiff seeks to enjoin and/or rescind the merger. In February 2018, Dominion Energy removed the case to the U.S. District Court for the District of South Carolina and filed a Motion to Dismiss in March 2018. In August 2018, the case was remanded back to the State Court of Common Pleas in Richland County. Dominion Energy appealed the decision to remand to the U.S. Court of Appeals for the Fourth Circuit, where the appeal was consolidated with another lawsuit regarding the SCANA Merger Agreement to which DESC is not a party. In June 2019, the U.S. Court of Appeals for the Fourth Circuit reversed the order remanding the case to state court. In September 2019, the U.S. District Court for the District of South Carolina granted the plaintiffs’ motion to consolidate the Metzler Lawsuit with another lawsuit regarding the SCANA Merger Agreement to which DESC is not a ~~party~~.party. In October 2019, the plaintiffs filed an amended complaint against certain former directors and executive officers of SCANA and DESC, which stated substantially

similar allegations to those in the initial lawsuits as well as an inseparable fraud claim. In November 2019, the defendants filed a motion to dismiss. In April 2020, the U.S. District Court for the District of South Carolina denied the motion to ~~dismiss~~.dismiss. In May 2020, SCANA filed a motion to intervene, which was denied in August 2020. In September 2020, SCANA filed a notice of appeal with the U.S. Court of Appeals for the Fourth Circuit. This case is pending.

In August 2017, a case was filed in the U.S. District Court for the District of South Carolina on behalf of persons who were formerly employed at the NND Project. In July 2018, the court certified this case as a class action. In February 2019, certain of these plaintiffs filed an additional case, which case has been dismissed and the plaintiffs have joined the case filed in August 2017. The plaintiffs allege, among other things, that SCANA, DESC, Fluor Corporation and Fluor Enterprises, Inc. violated the Worker Adjustment and Retraining Notification Act in connection with the decision to stop construction at the NND Project. The plaintiffs allege that the defendants failed to provide adequate advance written notice of their terminations of employment and are seeking damages, which ~~are estimated to~~could be as much as $100 million for 100% of the NND Project. In January 2021, the U.S. District Court for the District of South Carolina granted summary judgment in favor of SCANA, DESC, Fluor Corporation and Fluor Enterprises, Inc. In February 2021, the plaintiffs filed a notice of appeal with the U.S. Court of Appeals for the Fourth Circuit. This case is pending.

In September 2018, a case was filed in the State Court of Common Pleas in Fairfield County, South Carolina by Fluor Enterprises, Inc. and Fluor Daniel Maintenance Services, Inc. against DESC and Santee Cooper. The plaintiffs make claims for indemnification, breach of contract and promissory estoppel arising from, among other things, the defendants' alleged failure and refusal to defend and indemnify the Fluor defendants in the aforementioned case. ~~These cases are~~This case is pending.

In November 2017, Fairfield County filed a complaint and a motion for temporary injunction against DESC in the State Court of Common Pleas in Fairfield County, South Carolina, making allegations of breach of contract, fraud, negligent misrepresentation, breach of fiduciary duty, breach of implied duty of good faith and fair dealing and unfair trade practices related to DESC’s termination of the FILOT agreement between DESC and Fairfield County related to the NND Project. The plaintiff sought a temporary and permanent injunction to prevent DESC from terminating the FILOT agreement. The plaintiff withdrew the motion for temporary injunction in December 2017. This case is pending.

In June 2018, DESC received a notice of proposed assessment of approximately $410 million, excluding interest, from the SCDOR following its audit of DESC’s sales and use tax returns for the periods September 1, 2008 through December 31, 2017. The proposed assessment, which includes 100% of the NND Project, is based on the SCDOR’s position that DESC’s sales and use tax exemption for the NND Project does not apply because the facility will not become operational. ~~DESC has protested~~In December 2020, the ~~proposed assessment, which remains pending.~~parties reached an agreement in principle in the amount of $165 million to resolve this matter.

In September and October 2017, SCANA was served with subpoenas issued by the U.S. Attorney’s Office for the District of South Carolina and the Staff of the SEC’s Division of Enforcement seeking documents related to the NND Project. In February 2020, the SEC filed a complaint against SCANA, two of its former executive officers and DESC in the U.S. District Court for the District of South Carolina alleging that the defendants violated federal securities laws by making false and misleading statements about the NND Project. In April 2020, SCANA and DESC reached an agreement in principle with the Staff of the SEC’s Division of Enforcement to settle, without admitting or denying the allegations in the complaint. ~~The Staff~~In December 2020, the U.S. District Court for the District of South Carolina issued an order approving the ~~SEC’s Division of Enforcement has not yet presented the proposed~~ settlement ~~to the SEC. The agreement in principle would, among other things, require~~which required SCANA to pay a civil monetary penalty totaling $25 million, and SCANA and DESC to pay disgorgement and prejudgment interest totaling $112.5 million, which disgorgement and prejudgment interest amount ~~will be~~were deemed satisfied by the settlements in the SCANA Securities Class Action and the DESC Ratepayer Case. SCANA paid the civil penalty in December 2020. The ~~proposed settlement~~SEC civil action against two former executive officers of SCANA remains pending and is ~~contingent on~~currently subject to a stay granted by the ~~review and approval of final documentation by SCANA, DESC and~~court in June 2020 at the ~~Staff~~request of the ~~SEC’s Division of Enforcement and is subject to approval by the SEC and the~~ U.S. ~~District Court~~Attorney’s Office for the District of South Carolina. ~~This matter is pending.~~

In addition, the South Carolina Law Enforcement Division is conducting a criminal investigation into the handling of the NND Project by SCANA and DESC. Dominion Energy is cooperating fully with the investigations by the U.S. Attorney’s Office and the South Carolina Law Enforcement Division, including responding to additional subpoenas and document requests. Dominion Energy has also entered into a cooperation agreement with the U.S. Attorney’s Office and the South Carolina Attorney General’s Office. The cooperation agreement provides that in consideration of its full cooperation with these investigations to the satisfaction of both agencies, neither such agency will criminally prosecute or bring any civil action against Dominion Energy or any of its current, previous, or future direct or indirect subsidiaries related to the NND Project. ~~These matters are pending.~~A former executive officer of SCANA entered a plea agreement with the U.S. Attorney’s Office and the South Carolina Attorney General’s Office in June 2020 and entered a guilty plea with the U.S. District Court for the District of South Carolina in July 2020. Another former executive officer of SCANA entered a plea agreement with the U.S. Attorney's Office and the South Carolina Attorney General's Office in November 2020 and entered guilty pleas in the U.S. District Court for the District of South Carolina and in South Carolina state court in February 2021. As a result of the pleas, Dominion Energy has terminated indemnity for these former executive officers related to these two cases.

In December 2018, arbitration proceedings commenced between DESC and Cameco Corporation related to a supply agreement signed in May 2008. This agreement provides the terms and conditions under which DESC agreed to purchase uranium hexafluoride from

Cameco Corporation over a period from 2010 to 2020. Cameco Corporation alleges that DESC violated this agreement by failing to purchase the stated quantities of uranium hexafluoride for the 2017 and 2018 delivery years. DESC denies that it is in breach of the agreement and believes that it has reduced its purchase quantity within the terms of the agreement. This matter is pending.

In September 2019, a South Carolina state court jury awarded a judgment to the estate of Jose Larios in a wrongful death suit filed in June 2017 against DESC, of which DESC was apportioned $19 million. DESC holds general liability insurance coverage which is expected to provide payment for substantially all DESC’s liability in this matter. In October 2019, DESC filed a motion requesting a reduction in the judgment or, in the alternative, a new trial. In November 2019, DESC’s motion for a new trial was granted, setting aside the entire verdict amount. This matter is pending.

Westinghouse’s Reorganization Plan became effective August 1, 2018. Initially, Westinghouse had projected that its Reorganization Plan would pay in full or nearly in full its pre-petition trade creditors, including several of the Westinghouse Subcontractors which have alleged non-payment by the Consortium for amounts owed for work performed on the NND Project and have filed liens on related property in Fairfield County, South Carolina. DESC is contesting approximately $285 million of such filed liens. Most of these asserted liens are “pre-petition” claims that relate to work performed by Westinghouse Subcontractors before the Westinghouse bankruptcy, although some of them are “post-petition” claims arising from work performed after the Westinghouse bankruptcy. It is possible that the Reorganization Plan will not provide for payment in full or nearly in full to its pre-petition trade creditors. The shortfall could be significant. In addition, payments under the Toshiba Settlement are subject to reduction if Westinghouse pays Westinghouse Subcontractors holding pre-petition liens directly. Under these circumstances, DESC and Santee Cooper, each in its pro rata share, would be required to make Citibank, N.A., which purchased the scheduled payments under the Toshiba Settlement, whole for reductions related to valid subcontractor and vendor pre-petition liens up to $60 million ($33 million for DESC's 55% share).

DESC and Santee Cooper were responsible for amounts owed to Westinghouse for valid work performed by Westinghouse Subcontractors on the NND Project after the Westinghouse bankruptcy filing (i.e., post-petition) until termination of the IAA (the IAA Period). In the Westinghouse bankruptcy proceeding, deadlines were established for creditors of Westinghouse to assert the amounts owed to such creditors prior to the Westinghouse bankruptcy filing and during the IAA Period. Many of the Westinghouse Subcontractors have filed such claims. In December 2019, DESC and Santee Cooper entered into a confidential settlement agreement with W Wind Down Co LLC resolving claims relating to the IAA.

Further, some Westinghouse Subcontractors who have made claims against Westinghouse in the bankruptcy proceeding also filed against DESC and Santee Cooper in South Carolina state court for damages. The Westinghouse Subcontractor claims in South Carolina state court include common law claims for pre-petition work, IAA Period work, and work after the termination of the IAA. Many of these claimants have also asserted construction liens against the NND Project site. While DESC cannot be assured that it will not have any exposure on account of unpaid Westinghouse Subcontractor claims, which claims DESC is presently disputing, DESC believes it is unlikely that it will be required to make payments on account of such claims.

Under Price-Anderson, DESC (for itself and on behalf of Santee-Cooper) maintains agreements of indemnity with the U.S. Nuclear Regulatory Commission that, together with private insurance, cover third-party liability arising from any nuclear incident occurring at Summer. Price-Anderson provides funds up to ~~$14.0~~$13.7 billion for public liability claims that could arise from a single nuclear incident. Each nuclear plant is insured against this liability to a maximum of $450 million by American Nuclear Insurers with the remaining coverage provided by a mandatory program of deferred premiums that could be assessed, after a nuclear incident, against all owners of commercial nuclear reactors. Each reactor licensee is liable for up to $138 million per reactor owned for each nuclear incident occurring at any reactor in the U.S., provided that not more than $21 million of the liability per reactor would be assessed per year. DESC’s maximum assessment, based on its two-thirds ownership of Summer, would be $92 million per incident, but not more than $14 million per year. Both the maximum assessment per reactor and the maximum yearly assessment are adjusted for inflation at least every five years.

DESC currently maintains insurance policies (for itself and on behalf of Santee Cooper) with NEIL. The policies provide coverage to Summer for property damage and outage costs up to $2.75 billion resulting from an event of nuclear origin and up to $2.33 billion resulting from an event of a non-nuclear origin. The NEIL policies in aggregate, are subject to a maximum loss of $2.75 billion for any single loss occurrence. The NEIL policies permit retrospective assessments under certain conditions to cover insurer’s losses. Based on the current annual premium, DESC’s portion of the retrospective premium assessment would not exceed $24 million. DESC currently maintains an excess property insurance policy (for itself and on behalf of Santee Cooper) with EMANI. The policy provides coverage to Summer for property damage and outage costs up to $415 million resulting from an event of a non-nuclear origin. The EMANI policy permits retrospective assessments under certain conditions to cover insurer's losses. Based on the current annual premium, DESC's portion of the retrospective premium assessment would not exceed $2 million.

To the extent that insurable claims for property damage, decontamination, repair and replacement and other costs and expenses arising from an incident at Summer exceed the policy limits of insurance, or to the extent such insurance becomes unavailable in the future, and to the extent that DESC's rates would not recover the cost of any purchased replacement power, DESC will retain the risk of loss as a self-insurer. DESC has no reason to anticipate a serious nuclear or other incident. However, if such an incident were to occur, it likely would have a material impact on DESC's results of operations, cash flows and financial position.

~~In December 2019, DESC realigned its segments which resulted in the formation of a~~ ~~single~~ ~~primary operating segment. The historical information presented herein has been recast to reflect the current segment presentation.~~

The Corporate and Other segment includes specific items attributable to its operating segment that are not included in profit measures evaluated by executive management in assessing the segment’s performance or in allocating resources.

In the three months ended March 31, 2021 and 2020, DESC reported an immaterial amount of specific items in the Corporate and Other segment. In the three months ended March 31, 2019, DESC reported after-tax net expenses of $1.2 billion for specific items in the Corporate and Other segment, all of which were attributable to its operating segment.

~~The net expense for specific items attributable to DESC’s operating segment in 2019 primarily related to the impact of the following items:~~

DESC owns 40% of Canadys Refined Coal, LLC, which is involved in the manufacturing and sale of refined coal to reduce emissions at ~~certain~~one of DESC's generating facilities. DESC accounts for this investment using the equity method. ~~Purchases and sales of the related coal are recorded as other income (expense), net in the Consolidated Statements of Comprehensive Income (Loss).~~

DESC purchases natural gas and related pipeline capacity from SEMI to serve its retail gas customers and to satisfy certain electric generation requirements. These purchases are included within gas purchased for resale or fuel used in electric generation, as applicable in the Consolidated Statements of Comprehensive Income (Loss).

DESS, on behalf of itself and its parent company, ~~provides~~provided the following services to DESC through December 2020, which ~~are~~were rendered at direct or allocated cost: information systems, telecommunications, customer support, marketing and sales, human resources, corporate compliance, purchasing, financial, risk management, public affairs, legal, investor relations, gas supply and capacity management, strategic planning, general administrative and retirement benefits. In addition, DESS ~~processes~~processed and ~~pays~~paid invoices for DESC and iswas reimbursed. Effective January 2021, DES provides to DESC the services previously provided by DESS. Costs for these services include amounts capitalized. Amounts expensed are primarily recorded in other operations and maintenance - affiliated suppliers and other income (expense), net in the Consolidated Statements of Comprehensive Income (Loss).

Three Months Ended
March 31,

(millions)

2020

2019

Purchases of coal from affiliate

$
—

$
28

Sales of coal to affiliate

—

28

Purchases of fuel used in electric generation from affiliate

—

33

Direct and allocated costs from services company affiliate⁽¹⁾

67

58

Operating Revenues - Electric from sales to affiliate

—

1

Operating Expenses - Other taxes from affiliate

3

2

Purchases of electricity from solar affiliates

2

1

Demand and transportation charges from DECG - Fuel used in electric generation

4

11

Demand and transportation charges from DECG - Gas purchased for resale

11

4

	Three Months Ended March 31,
(millions)	2021		2020
Direct and allocated costs from DES and DESS⁽¹⁾	$	55	$	67
Operating Revenues - Electric from sales to affiliate		1		0
Operating Revenues - Gas from sales of affiliate		0		0
Operating Expenses - Other taxes from affiliate		3		3
Purchases of electricity from solar affiliates		2		2
Demand and transportation charges from DECG - Fuel used in electric generation		0		4
Demand and transportation charges from DECG - Gas purchased for resale		0		11

	Three Months Ended March 31,						Three Months Ended March 31,
(millions)	2020			2019			2021		2020
Revenues from contracts with customers	$	1		$	1		$	0	$	1
Other income		3			4			3		3
Other expense		(2	)		(10	)		2		(2	)
Allowance for equity funds used during construction		1			—			1		1
Other income (expense), net	$	3		$	(5	)
Other income, net							$	6	$	3

Non-service cost components of pension and other postretirement benefits are included in other income (expense).

ITEM 2. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS

MD&A provides management’s narrative analysis of its consolidated results of ~~operation.~~operations. MD&A should be read in conjunction with DESC's Consolidated Financial Statements. DESC meets the conditions to file under the reduced disclosure format, and therefore has omitted certain sections of MD&A.

This report contains statements concerning DESC’s expectations, plans, objectives, future financial performance and other statements that are not historical facts. These statements are “forward-looking ~~statements” within the meaning of the Private Securities Litigation Reform Act of 1995.~~statements.” In most cases, the reader can identify these forward-looking statements by such words as “anticipate,” “estimate,” “forecast,” “expect,” “believe,” “should,” “could,” “plan,” “may,” “continue,” “target” or other similar words.

DESC makes forward-looking statements with full knowledge that risks and uncertainties exist that may cause actual results to differ materially from predicted results. Factors that may cause actual results to differ are often presented with the forward-looking statements themselves. Additionally, other factors may cause actual results to differ materially from those indicated in any forward-looking statement. These factors include but are not limited to:

Additionally, other risks that could cause actual results to differ from predicted results are set forth in Part I. Item 1A. Risk Factors in DESC’s Annual Report on Form 10-K for the year ended December 31, ~~2019, as updated in Part II, Item 1A. Risk Factors in this report.~~2020.

DESC’s forward-looking statements are based on beliefs and assumptions using information available at the time the statements are made. DESC cautions the reader not to place undue reliance on its forward-looking statements because the assumptions, beliefs, expectations and projections about future events may, and often do, differ materially from actual results. DESC undertakes no obligation to update any forward-looking statement to reflect developments occurring after the statement is made.

	First Quarter							First Quarter
(millions)	2020		2019			$ Change		2021		2020		$ Change
Net income (loss)	$	93	$	(1,103	)	$	1,196
Net income								$	55	$	93	$	(38)

Net income ~~increased $1.2 billion,~~decreased 41%, primarily due to the absence of charges for refunds of amounts previously collected from retail electric customers for the NND Project and certain regulatory assets and utility plant for which DESC committed to forgo recovery and a decrease in charges associated with litigation.

	First Quarter								Year-To-Date
(millions)	2020		2019			$ Change			2021		2020		$ Change
Operating revenues	$	672	$	(335	)	$	1,007		$	744	$	672	$	72
Fuel used in electric generation		104		137			(33	)		132		104		28
Purchased power		13		8			5			16		13		3
Gas purchased for resale		57		77			(20	)		81		57		24
Net revenue		498		(557	)		1,055
Other operations and maintenance		145		144			1			152		145		7
Impairment of assets and other charges		2		271			(269	)		60		2		58
Depreciation and amortization		118		102			16			121		118		3
Other taxes		62		69			(7	)		65		62		3
Other income (expense), net		3		(5	)		8
Other income, net										6		3		3
Interest charges		58		73			(15	)		55		58		(3	)
Income tax expense (benefit)		23		(118	)		141
Income tax expense										13		23		(10	)

Fuel used in electric generation increased 27%, primarily due to increased fuel costs associated with electric utility retail customers, which are offset in operating revenue and do not impact net income.

Gas purchased for resale increased 42%, primarily due to an increase in costs associated with gas utility customers, which are offset in operating revenue and do not impact net income.

Other operations and maintenance increased 5%, primarily due to an increase in salaries, wages and benefits and administrative expenses.

Impairment of assets and other charges ~~decreased 99%, primarily due to a reduction in charges associated with litigation ($166 million) and a decrease in charges for utility plant for which DESC committed to forgo recovery ($103 million).~~

~~Depreciation and amortization~~ ~~increased 16%, primarily reflecting the amortization of NND Project costs.~~

~~Other taxes~~ ~~decreased 10%, primarily due to a decrease in property taxes.~~

~~Other income (expense), net~~ increased $8$58 million, primarily due to ~~a decrease in donations ($4 million) and a decrease in severance expenses ($3 million).~~charges associated with litigation.

~~Interest charges~~Income tax expense decreased ~~21%~~43%, primarily due to lower ~~long-term debt principal balances primarily as a result of the debt tender offers completed in 2019.~~pre-tax income.

~~Income tax expense~~ increased $141 million, primarily due to the absence of a charge for certain income tax-related regulatory assets for which DESC committed to forgo recovery ($198 million) and the absence of changes in unrecognized tax benefits ($40 million), partially offset by higher pretax income ($379 million).

Senior management of DESC, including DESC’s CEO and CFO, evaluated the effectiveness of DESC’s disclosure controls and procedures as of the end of the period covered by this report. Based on this evaluation process, DESC’s CEO and CFO have concluded that DESC’s disclosure controls and procedures are effective.

In the first quarter of 2021, DESC completed the integration of its systems and processes into Dominion Energy’s framework of internal control over financial reporting. As part of this process, DESC transitioned its financial activity into Dominion Energy’s accounting system. Throughout this integration and system implementation, DESC appropriately considered internal controls over financial reporting.

~~There~~Other than with respect to this item, there were no changes that occurred during the last fiscal quarter that ~~have~~ materially affected, or are reasonably likely to materially affect, DESC’s internal control over financial reporting.

From time to time, DESC is ~~alleged~~party to be in violation or in default under orders, statutes, rules or regulations relating to the environment, compliance plans imposed upon or agreed to by DESC, or permits issued by various local, state and/or federal agencies for the construction or operation of facilities. Administrative proceedings may also be pending on these matters. In addition, DESC is involved in various legal, environmental or other regulatory proceedings, ~~from time to time, whether~~including in the ordinary course of ~~business or particularly following~~business. SEC regulations require disclosure of certain environmental matters when a governmental authority is a party to the ~~abandonment~~proceedings and such proceedings involve potential monetary sanctions that DESC reasonably believes will exceed a specified threshold. Pursuant to the SEC regulations, DESC uses a threshold of ~~the NND Project.~~$1 million for such proceedings.

See the following for discussions on various legal, environmental and other regulatory proceedings to which DESC is a party, which information is incorporated herein by reference:

DESC’s business is influenced by many factors that are difficult to predict, involve uncertainties that may materially affect actual results and are often beyond its control. A number of these risk factors have been identified in DESC’s Annual Report on Form 10-K for the year ended December 31, ~~2019,~~2020, which should be taken into consideration when reviewing the information contained in this report. ~~Other than the risk factor discussed below, there~~There have been no material changes with regard to the risk factors previously disclosed in DESC's Annual Report on Form 10-K for the year ended December 31, ~~2019.~~2020. For other factors that may cause actual results to differ materially from those indicated in any forward-looking statement or projection contained in this report, see Forward-Looking Statements in MD&A in this report.

~~Public health crises and epidemics or pandemics, such as COVID-19, could adversely affect DESC’s business, results of operations, financial condition, liquidity and/or cash flows.~~

The effects of the continued outbreak of the COVID-19 pandemic and related government responses could include extended disruptions to supply chains and capital markets, reduced labor availability and productivity and a prolonged reduction in economic activity. The effects could also have a variety of adverse impacts on DESC, including reduced demand for energy, particularly from commercial and industrial customers and impairment of goodwill or long-lived assets. There is considerable uncertainty regarding the extent to which COVID-19 will spread and the extent and duration of measures to try to contain the virus, such as travel bans and restrictions, quarantines, shelter in place orders, and shutdowns. Such restrictions may cause operational interruptions and delays in construction projects. For the duration of the outbreak of COVID-19, voluntary suspension, or potential legislative or government action, is expected to limit DESC’s ability to collect on overdue accounts or disconnect services for non-payment, which may cause a decrease in DESC’s results of operations and cash flows. To the extent the COVID-19 pandemic adversely affects DESC’s business, results of operations, financial condition, liquidity and/or cash flows, it may also have the effect of heightening many of the other risks described in Item 1A. Risk Factors in DESC’s Annual Report on Form 10-K for the year ended December 31, 2019.

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized.

		I.R.S. Employer
Commission File Number	Exact name of registrant as specified in its charter	Identification Number

001-3375	DOMINION ENERGY SOUTH CAROLINA, INC.	57-0248695

	south carolina
	(State or other jurisdiction of incorporation or organization)

	400 OTARRE PARKWAY
	CAYCE, South Carolina	29033
	(Address of principal executive offices)	(Zip Code)

	(803) 217-9000
	(Registrants’ telephone number)

		Page
	Glossary of Terms	3

PART I. FINANCIAL INFORMATION

Item 1.	Financial Statements	5

Item 2.	Management's Discussion and Analysis of Financial Condition and Results of Operations	2726

Item 4.	Controls and Procedures	29

PART II. OTHER INFORMATION

Item 1.	Legal Proceedings	30

Item 1A.	Risk Factors	30

Item 6.	Exhibits	31

~~Abbreviation or Acronym~~		~~Definition~~
NND Project		V. C. Summer Units 2 and 3 nuclear development project under which DESC and Santee Cooper undertook to construct two Westinghouse AP1000 Advanced Passive Safety nuclear units in Jenkinsville, South Carolina
~~NSPS~~NO_x		~~New Source Performance Standards~~Nitrogen oxide

Abbreviation or Acronym		Definition
Order 1000		Order issued by FERC adopting requirements for electric transmission planning, cost allocation and development
Price-Anderson		Price-Anderson Amendments Act of 1988
PSD		Prevention of significant deterioration
Questar Gas		Questar Gas Company, a wholly-owned subsidiary of Dominion Energy
Reorganization Plan		Modified Second Amended Joint Chapter 11 Plan of Reorganization, filed by Westinghouse
RICO		Racketeer Influenced and Corrupt Organizations Act
Santee Cooper		South Carolina Public Service Authority
SCANA		The legal entity, SCANA Corporation, one or more of its consolidated subsidiaries (other than DESC) or the entirety of SCANA Corporation and its consolidated subsidiaries
SCANA Combination		Dominion Energy's acquisition of SCANA completed on January 1, 2019 pursuant to the terms of the SCANA Merger Agreement
SCANA Merger Agreement		Agreement and plan of merger entered on January 2, 2018 between Dominion Energy and SCANA
SCANA Merger Approval Order		Final order issued by the South Carolina Commission on December 21, 2018 setting forth its approval of the SCANA Combination
SCDHEC		South Carolina Department of Health and Environmental Control
SCDOR		South Carolina Department of Revenue
SEC		U.S. Securities and Exchange Commission
~~SEMI~~SO₂		SCANA Energy Marketing, LLC (formerly known as SCANA Energy Marketing, Inc.), a subsidiary of SCANA through December 2019, and effective December 2019, a subsidiary of Wrangler Retail Gas Holdings, LLC, a partnership between Dominion Energy and Interstate Gas Supply Inc.Sulfur dioxide
South Carolina Commission		Public Service Commission of South Carolina
Summer		V. C. Summer nuclear power station
Toshiba		Toshiba Corporation, parent company of Westinghouse
Toshiba Settlement		Settlement Agreement dated as of July 27, 2017, by and among Toshiba, DESC and Santee Cooper
VIE		Variable interest entity
Virginia Power		The legal entity, Virginia Electric and Power Company, a wholly-owned subsidiary of Dominion Energy, one or more of its consolidated subsidiaries or operating segment, or the entirety of Virginia Electric and Power Company and its consolidated subsidiaries
~~VOC~~		~~Volatile organic compounds~~
WECTEC		WECTEC Global Project Services, Inc., a wholly-owned subsidiary of Westinghouse
Westinghouse		Westinghouse Electric Company LLC
Westinghouse Subcontractors		Subcontractors and suppliers to the Consortium

Exhibit No.		Description
3.1		Amended and Restated Articles of Incorporation, effective April 29, 2019 (Exhibit 3.1, Form 8-K filed April 29, 2019, File No. 1-3375).
3.2		Amended and Restated Bylaws, effective April 29, 2019 (Exhibit 3.2, Form 8-K filed April 29, 2019, File No. 1-3375).
4.1		Dominion Energy South Carolina, Inc. agrees to furnish to the U.S. Securities and Exchange Commission upon request any instrument with respect to long-term debt as to which the total amount of securities authorized does not exceed 10% of its total consolidated assets.
31.a		Certification by Chief Executive Officer of Dominion Energy South Carolina, Inc. pursuant to Section 302 of the Sarbanes-Oxley Act of 2002 (filed herewith).
31.b		Certification by Chief Financial Officer of Dominion Energy South Carolina, Inc. pursuant to Section 302 of the Sarbanes-Oxley Act of 2002 (filed herewith).
32.a		Certification to the Securities and Exchange Commission by Chief Executive Officer and Chief Financial Officer of Dominion Energy South Carolina, Inc. as required by Section 906 of the Sarbanes-Oxley Act of 2002 (furnished herewith).
101		The following financial statements from Dominion Energy South Carolina, Inc.’s Quarterly Report on Form 10-Q for the quarter ended March 31, ~~2020,~~2021, filed on May ~~5, 2020,~~4, 2021, formatted in iXBRL (Inline eXtensible Reporting Language): (i) Consolidated Balance Sheets, (ii) Consolidated Statements of Comprehensive Income (Loss), (iii) Consolidated Statements of Cash Flows, (iv) Consolidated Statements of Changes in Common Equity, and (v) the Notes to Consolidated Financial Statements.
104		Cover Page Interactive Data File (formatted in iXBRL (Inline eXtensible Reporting Language) and contained in Exhibit 101).


☒	QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934


☐	TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

Large accelerated filer	☐		Accelerated filer	☐	Emerging growth company	☐
Non-accelerated filer	☒		Smaller reporting company	☐

(millions)		Amount of Gain (Loss) Recognized in Income on Derivatives⁽¹⁾
Three Months Ended March 31,	Location	2021			2020
Derivative type and location of gains (losses):
Interest rate contracts:	Interest charges	$	(1	)	$	0
Total interest rate contracts		$	(1	)	$	0

(millions)	External Revenue		Comprehensive Income (Loss) Available (Attributable) to Common Shareholder
Three Months Ended March 31, 2021
Dominion Energy South Carolina	$	744	$	97
Corporate and Other		0		(46	)
Consolidated Total	$	744	$	51

Three Months Ended March 31, 2020
Dominion Energy South Carolina	$	672	$	89
Corporate and Other		0		(1	)
Consolidated Total	$	672	$	88

	DOMINION ENERGY SOUTH CAROLINA, INC.
		(Registrant)

	By:	/s/ Michele L. Cardiff
Date: May ~~5, 2020~~4, 2021		Michele L. Cardiff
		Senior Vice President, Controller and Chief Accounting Officer