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•	the inability to successfully integrate into the operations of AltaGas and a failure to realize anticipated benefits;

•	the effect of the consummation of the merger on our ability to maintain supplier relationships, keep customers, and retain and hire key personnel;

•	unexpected costs incurred in connection with the Merger;

•	the inability to meet commitments under various orders and agreements associated with regulatory approvals for the merger, which could have a detrimental impact on our business, financial condition, operating results and prospects;

•	the loss of certain administrative and management functions and services provided by AltaGas;

•	potential litigation in connection with the merger;

•	changes in AltaGas' strategy or relationship with Washington Gas that could affect our performance or operations;

•	changes in our credit rating, WGL's, or AltaGas' credit ratings, and disruptions in credit market conditions or other factors that may affect our access to and cost of capital;

•	the level and rate at which we incur costs and expenses, and the extent to which we are allowed to recover from customers, through the regulatory process, such costs and expenses relating to constructing, operating and maintaining our distribution system;

•	the availability of natural gas supply, interstate pipeline transportation and storage capacity;

•	leaks, mechanical problems, incidents or other operational issues in our natural gas distribution system, including the effectiveness of our efforts to mitigate the effects of receiving low-HHC natural gas;

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•	changes in laws and regulations affecting our business, including in the areas of the environment, pipeline integrity, and employment;

•	changes in energy commodity market conditions, including the relative prices of alternative forms of energy such as electricity, fuel oil and propane;

•	disruptions or decline in the local economy in which Washington Gas operates;

•	strikes or work stoppages by unionized employees;

•	costs of providing retirement plan benefits is subject to change;

•	changes to government fiscal and trade policies;

•	security breaches of our information technology infrastructure, including cyber-attacks and cyber-terrorism;

•	acts of nature and catastrophic events, including terrorist acts;

•	the credit-worthiness of customers; suppliers and derivatives counterparties;

•	changes in the value of derivative contracts and the availability of suitable derivative counterparties;

•	rules implementing the derivatives transaction provisions of the Dodd-Frank Act may impose costs on our derivatives activities;

•	unusual weather conditions and changes in natural gas consumption patterns;

•	legislative, regulatory, and judicial mandates or decisions affecting our operations, including interpretations of the Tax Cuts and Jobs Act of 2017 (Tax Act);

•	our ability to manage the outsourcing of several business processes;

•	the outcome of new and existing matters before courts, regulators, government agencies or arbitrators, including that relating to the August 2016 explosion and fire at an apartment complex in Silver Spring, Maryland;

•	changes in accounting principles and the effect of accounting pronouncements issued periodically by accounting standard-setting bodies.

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•	the complexity of the site;

•	changes in environmental laws and regulations at the federal, state and local levels;

•	the number of regulatory agencies or other parties involved;

•	new technology that renders previous technology obsolete or experience with existing technology that proves ineffective;

•	the level of remediation required and

•	variation between the estimated and actual period of time required to respond to an environmentally contaminated site.

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•	higher operation and maintenance expenses primarily related to system safety and operational expenses, corporate allocations and higher employee related expenses;

•	lower realized margins and higher unrealized mark-to-market valuation loss associated with our asset optimization program; and

•	lower billed and estimated utility rates associated with the pass-through of future tax savings from the Tax Act, however the decrease is offset by lower income tax expense which is not included in EBIT.

•	customer growth of approximately 14,000 average active customer meters;

•	higher revenues attributed to colder weather in the District of Columbia; and

•	new base rates in Maryland.

•	higher operation and maintenance expenses primarily related to merger commitments and related expenses;

•	lower realized margins and unrealized mark-to-market valuations associated with our asset optimization program;

•	lower billed and estimated utility rates associated with the pass-through of future tax savings from the Tax Act, however the decrease is offset by lower income tax expense; and

•	higher depreciation and amortization expenses associated with growth in our utility plant.

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•	customer growth of approximately 18,000 average active customer meters;

•	higher revenues attributed to colder weather in the District of Columbia; and

•	new base rates in the District of Columbia and Virginia.

•	new base rates in Virginia and the District of Columbia;

•	higher utility net revenue related to growth of approximately 13,000 average active customer meters; and

•	higher unrealized mark-to-market valuations associated with our asset optimization program.

•	higher depreciation and amortization expense; and

•	higher operation and maintenance expenses.

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(a)	Represents minimum payments for natural gas transportation, storage and peaking contracts.

(b)	Represents scheduled repayment of principal.

(c)	Represents the scheduled interest payments associated with long-term debt.

(d)	Includes known and reasonably likely commitments to purchase fixed volumes of natural gas. Cost estimates are based on forward market prices as of December 31, 2018. Certain of our gas purchase agreements have optionality, which may cause increases in these commitments.

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•	Discount rate,

•	Expected long-term return on plan assets,

•	Rate of compensation increase,

•	Healthcare cost trend rate and

•	Projected increases to the Health Reimbursement Account (HRA) plan stipend.

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•	Price Risk

•	Weather Risk

•	Interest-Rate Risk

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•	the complexity of the site;

•	changes in environmental laws and regulations at the federal, state and local levels;

•	the number of regulatory agencies or other parties involved;

•	new technology that renders previous technology obsolete or experience with existing technology that proves ineffective;

•	the level of remediation required; and

•	variations between the estimated and actual period of time that must be dedicated to respond to an environmentally-contaminated site.

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1)	Hiring of three damage prevention trainers and community outreach in each jurisdiction for a total of $2.4 million over 5 years;

2)	Investment of up to $70.0 million over a 10-year period to further extend natural gas service to areas within Washington Gas' service territory, which will be incorporated into Washington Gas's ongoing capital plan;

3)	Spending $8.0 million on leak mitigation and reducing leak backlogs within 3 years after the Merger close; and

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•	align management’s interests with the customers of Washington Gas by rewarding the provision of safe and reliable gas delivery to customers at a reasonable cost.

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80% of the Named Executive Officer awards are performance units to be earned based on performance against ROE Ratio and Adjusted Funds from Operations (AFFO) goals on an equally weighted basis. Participants will have the ability to earn 0% - 200% of the target number of units based on achievement of the ROE Ratio and AFFO goals. The number of units earned will then have the ability to be modified +/- 20% based on the relative TSR performance of AltaGas stock against comparator groups. The maximum payout opportunity cannot exceed 200% of target even when including the modifier. Performance units will vest on the third anniversary of the grant date.

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20% of the Named Executive Officer awards are in the form of restricted units. One-third of the restricted units granted will vest on each of October 1, 2019, October 1, 2020, and October 1, 2021 assuming AltaGas pays a dividend over the 12- month period prior to each vesting date. If AltaGas does not pay a dividend during each year of the performance period, the restricted units which would have otherwise vested will be forfeited.

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•	tax-qualified employee benefit plans that are available to our employees, including the Washington Gas Light Company Savings Plan (which we refer to, together with the Washington Gas Light Company Capital Appreciation Plan/ Union Employees’ Savings Plan, as the “401(k) Plans”), and the Washington Gas Light Company Employees’ Pension Plan (the “Pension Plan”);

•	the Washington Gas Light Company Defined Contribution Supplemental Executive Retirement Plan (“DC SERP”);

•	the Washington Gas Light Company Defined Contribution Restoration Plan (the “Defined Contribution Restoration Plan” or “DC Restoration Plan”); and

•	the Washington Gas Light Company Defined Benefit Restoration Plan (the “Defined Benefit Restoration Plan” or “DB Restoration Plan”).

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•	Base salary changes for the Transition Period were determined at the September 17, 2018 HR Committee meeting and the September 18, 2018 Board meeting and implemented on October 1, 2018;

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•	Performance unit and restricted unit grants were approved at the September 17, 2018 HR Committee meeting for grants effective on October 1, 2018 (or December 17, 2018 in the case of Messrs. Chapman and Ammann and Ms. Gutermuth); and

•	Transition Period STI payments for the Transition Period were approved at the HR Committee meeting held on January 29, 2019 and the Board meeting held on February 21, 2019.

•	Our performance goals and objectives reflect a balanced mix of performance measures to avoid excessive weight on a certain goal or performance measure;

•	Total direct compensation levels are heavily weighted towards long-term, incentive awards with vesting schedules that fully materialize over a number of years; and

•	Long-term incentive awards are granted annually so executives always have unvested awards that could decrease significantly in value if our business is not managed for the long term.

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•	We determined that, as of December 31, 2018, our employee population consisted of approximately 1,559 individuals, with all of these individuals located in the United States. This population consisted of our full-time, part-time, and temporary employees, and does not include any independent contractors that we have engaged.

•	To identify the median employee from our employee population, we compared the amount of total compensation (consisting of salaries and overtime) of our employees as reflected in our payroll records as of December 31, 2018. We identified our median employee using this compensation measure, which was consistently applied to all employees included in the calculation.

•	Once we identified our median employee, we combined all of the elements of such employee’s compensation for the Transition Period in accordance with the requirements of Item 402(c)(2)(x) of Regulation S-K, resulting in Transition Period total compensation of $28,204.

•	For the Transition Period total compensation of Mr. Chapman, we used the amount reported in the “Total” column (column (j)) of our 2018T Summary Compensation Table included in this Form 10-KT.

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•	the 401(k) Plan, a tax-qualified defined-contribution plan in which the Named Executive Officers participate on the same terms as our other participating employees;

•	the Pension Plan, a tax-qualified, non-contributory pension plan covering all active employees (including executive officers) and vested former employees of Washington Gas;

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•	the DB SERP, a non-qualified defined-benefit retirement plan which provides the Named Executive Officers a benefit up to 60% of the individual’s final average compensation, as determined under that plan;

•	the DC SERP, a non-qualified defined-contribution retirement plan;

•	the Defined Benefit Restoration Plan, a non-qualified defined-benefit retirement plan; and

•	the Defined Contribution Restoration Plan, a non-qualified defined-contribution retirement plan.

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•	for Messrs. Staebler and Frye, salary replacement benefits equal to the sum of the executive’s annual base salary plus annual target incentive bonus multiplied by two, net of any retention payment that has already been received;

•	for Messrs. Staebler and Frye, the product of the executive’s annual bonus and a fraction, the numerator of which is the number of days in the current fiscal year through the termination date, and the denominator of which is 365;

•	medical and dental replacement benefits for three years for Messrs. Chapman and Ammann; and such benefits for two years for Ms. Gutermuth and Messrs. Staebler and Frye;

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an additional three years of benefit service under the DB SERP for Messrs. Chapman, Ammann, and two years for Messrs. Staebler and Frye provided, in no event shall such additional service, when added to the executive’s DB SERP benefit service, exceed the maximum of 30 years (Ms. Gutermuth does not participate in the DB SERP; her benefits under the DC SERP and the DB Restoration were 100% vested upon the Merger);

•	for Messrs. Staebler and Frye, outplacement services of up to $25,000; provided that such services are incurred by the executive within 12 months of his or her termination.

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assignment to the participant, without his or her consent, of duties inconsistent in any material respect with the executive’s then current position or duties (including, for Messrs. Chapman and Ammann, not having their current position at the most senior resulting entity following the change in control), or any other action by the company which would cause him or her to violate ethical or professional obligations, or which results in a significant diminution in such position or duties;

•	the participant, without his or her consent, being required to relocate to a principal place of employment that is both more than 35 miles from his or her existing principal place of employment, and farther from the participant’s current residence than his or her existing principal place of employment;

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the company materially reduces, without his or her consent, the participant’s base salary rate or target bonus opportunity, or materially reduces the aggregate value of other incentives and retirement opportunity, or fails to allow the participant to participate in all welfare benefit plans, incentive, savings and retirement plan, fringe benefit plans and vacation benefits applicable to other senior executives; or

•	the company fails to obtain a satisfactory agreement from any successor entity to assume and agree to perform the company’s obligations to the Named Executive Officer under the CIC Plan.

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•	To better match the accounting recognition of transactions with their economics;

•	To better align with regulatory view/recognition;

•	To eliminate the effects of:

i.	Significant out of period adjustments;

ii.	Other significant items that may obscure historical earnings comparisons and are not indicative of performance trends; and

iii.	For adjusted EBIT, other items which may obscure segment comparisons.

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