Maryann T. Mannen
Executive Vice President and Chief Financial Officer at Marathon Petroleum
Thanks, Mike. Slide six provides a summary of our second quarter financial results. This morning, we reported an adjusted earnings per share of $0.67. Adjusted EBITDA was $2.194 billion for the quarter. This includes the results from both continuing and discontinued operations. Cash from continuing operations, excluding working capital, was $1.535 billion, which is approximately $1 billion increase from the prior quarter. And for the first time in nearly 18 months, we generated ongoing operating cash flow that exceeded the needs of the business, capital commitments as well as covered our dividend and distributions. Finally, we returned nearly $1.4 billion of capital to shareholders this quarter through dividend payments and share repurchases. The close of the Speedway sale marked a significant milestone in our ongoing commitment to strengthen the competitive position of our portfolio. So we wanted to call out some of the key points on slide seven.
We received total proceeds for the sale of Speedway of $21 billion. Based on our tax basis, our cash taxes, current and deferred, will be approximately $4.2 billion, which is lower than our original $4.5 billion estimate. We have accrued for this on the balance sheet. In addition, we had closing adjustments of approximately $400 million. Therefore, the after-tax proceeds from the sale will be $17.2 billion. To be clear, this number is higher than our initial $16.5 billion estimate. On slide eight, we present an overview of the use of the proceeds. Since the close of the transaction, we have reduced structural debt by $2.5 billion and purchased approximately $1 billion of stock. In the post-tender period, we did not repurchase any incremental shares in light of a couple of regulatory constraints: first, a post-tender cooling off period; and second, our routine quarterly restricted period in the lead up to the release of our earnings information.
That said, not repurchasing during that limited window is not indicative of any deviation from our commitment to complete within 12 to 16 months. Consistent with that commitment, as Mike mentioned earlier, we are commencing the next steps to complete the remaining $9 billion return of capital. Specifically, we are entering into an open-market repurchase program that will allow us to buy for a period of time, including when the company may have information that otherwise precludes us from trading, and we will provide updates on the progress during our earnings calls. Slide nine illustrates the progress we have made, lowering our cost structure. Since the beginning of 2020, we have made a step change in our refining operating cost and decreased our overall cost profile by approximately $1 billion. While there is quarter-to-quarter variability, our refining operating cost in 2020 began at $6 per barrel and are now trending at a quarterly average of roughly $5 per barrel for 2021.
We have applied the same cost discipline framework that we use for refining operating costs to our corporate costs as well. There may be variations in these corporate costs quarter-to-quarter. We believe we have lowered our overall cost structure by more than $100 million, and we are committed to challenging ourselves every day on ways to reduce expenses. As you know, natural gas is a variable cost in operating a refinery. These costs have recently increased nearly $1 per MMBtu, and we anticipate this being a headwind for the third quarter. While our results reflect our focus on cost discipline, every day, we remain steadfast in our commitment to safely operate our assets and protect the health and safety of our employees, customers and the communities in which we operate. As we have shared with you previously, our cost reductions should be sustainable, not impact revenue opportunities, and in no way, jeopardize the safety of our people or our operations.
Slide ten shows the reconciliation from net income to adjusted EBITDA as well as the sequential change in adjusted EBITDA from first quarter 2021 to second quarter 2021. Adjusted EBITDA was more than $600 million higher quarter-over-quarter, driven primarily by refining and marketing. As we previously mentioned, this quarter's results include the impacts of closing the Speedway sale. Here, you can see the $11.7 billion pretax gain on the sale reflected in the adjustments column of $11.6 billion, which includes other adjustments of $79 million for impairment and transaction-related costs. The $3.7 billion financial tax -- excuse me, financial tax provision reflects the net impact of cash taxes and deferred tax impact. The resulting $8 billion gain on sale is reflected in our quarterly net income. Slide eighteen in our appendix walk through the specific impacts of the Speedway sale across the three financial statements.
Moving to our segment slide -- results. Slide eleven provides an overview of our Refining and Marketing segment. The business recorded the second consecutive quarter of positive EBITDA since the start of the COVID pandemic with adjusted EBITDA of $751 million. This was an increase of $728 million when compared to the first quarter of 2021. The increase was driven primarily by higher refining margins, especially in the Mid-Con region as that region's cracks improved 57% from the first quarter. Also contributing to the improved results was higher utilization, which was 94% for the second quarter versus 83% in the first quarter. It's important to recall that we idled two high-cost refineries in 2020. If adjusted to include that capacity idled in 2020, utilization would have been approximately 78% in the first quarter of '21 and subsequently increased to 89% in the second quarter of '21.
Operating expenses were relatively flat with the previous quarter despite the increase in utilization, reflecting the team's commitment to cost discipline despite rising variable cost. Slide twelve shows the change in our Midstream EBITDA versus the first quarter of 2021. Our Midstream segment continues to demonstrate earnings resiliency and stability with consistent results from the previous quarter. Here again, the team continues to make excellent progress executing on the strategic priorities of strict capital discipline, lowering the cost structure and portfolio optimization. By the end of 2021, we estimate that MPLX will have decreased their structural cost by $300 million. Slide thirteen presents the elements of change in our consolidated cash position for the second quarter.
It reflects both our continuing and discontinued operations. We have also specifically called out items related to the Speedway close. Within continuing operations, operating cash flow before changes in working capital was $1.5 billion in the quarter. Changes in working capital were flat this quarter. Increasing crude prices provided a source of more than $500 million, which was mostly offset by the large receivable balance with Speedway becoming a third-party customer and typical seasonal refined product inventory builds. During the quarter, MPC decreased debt by $3.3 billion. Additionally, MPLX reduced third-party debt by approximately $800 million during the quarter. With respect to capital return, MPC returned $380 million to shareholders through our dividend and repurchased $981 million worth of shares using Speedway proceeds.
At the end of the quarter, NPC had $17.3 billion in cash and higher returning short-term investments, such as commercial paper and certificates of deposits. Turning to guidance. On slide fourteen, we provide our third quarter outlook. We expect total throughput volumes of roughly 2.8 million barrels per day. Planned turnaround costs are projected to be approximately $195 million in the third quarter. The majority of the activity will be at our Robinson and Mandan refineries in the Mid-Con region. As we have previously mentioned, our turnaround activity is back-half weighted this year. Other operating expenses are coordinated to occur during these time periods as well. And so you are seeing the impact in our guided cost trends for the third quarter. Total operating costs are projected to be $5.05 per barrel for the quarter. Distribution costs are expected to be approximately $1.3 billion for the quarter. Corporate costs are expected to be $175 million, consistent with the second quarter and reflecting the approximately $100 billion -- $100 million, excuse me, in cost that have been removed on an annual basis. With that, let me turn the call back over to Kristina.