I would now like to hand the conference over to your speaker today, Ms.
Tiffany Samas, Manager of Investor Relations. Please go ahead.
Good morning, and welcome to the Natural Resource Partners second quarter twenty twenty one conference call. Today's call is being webcast, and a replay will be available on our website. Joining me today are Craig Nunez, President and Chief Operating Officer Chris Zolas, Chief Financial Officer and Kevin Craig, Executive Vice President. Some of our comments today may include forward looking statements reflecting NRP's views about future events. These matters involve risks and uncertainties that could cause our actual results to materially differ from our forward looking statements.
These risks are discussed in NRP's Form 10 ks and other Securities and Exchange Commission filings. We undertake no obligation to revise or update publicly any forward looking statements for any reason. Our comments today also include non GAAP financial measures. Additional details and reconciliations to the most directly comparable GAAP measures are included in our second quarter press release, which can be found on our website. I would like to remind everyone that we do not intend to discuss the operations or outlook for any particular coal lessee or detailed market fundamentals.
In addition, I refer you to Ciner Resources' public disclosures and commentary for specific questions regarding our soda ash business segment. Now I would like to turn the call over to Craig Nunes, our President and Chief Operating Officer.
Thank you, Tiffany. Good morning all. NRP continues to operate under CDC guidelines and company pandemic work protocols. I am pleased to report that our business continues to improve as the global economy recovers from the pandemic induced shock that began last year. Demand for metallurgical coal, thermal coal, and soda ash is strong, and prices for those commodities have increased significantly since the beginning of the year.
While the current resurgence of COVID nineteen infections in The US and various regions of the world highlights the ongoing risk that COVID nineteen poses for the global economy, we remain cautiously optimistic that the worst impacts of the pandemic for our company are behind us. Furthermore, and as you've heard me say repeatedly in the past, we remain quite pleased with the partnership's durability during challenging economic environments as demonstrated by its ability to generate free cash flow, continue paying down debt, and maintain strong liquidity throughout the past year and a half. We believe this durability will continue. Over the last twelve months, we generated $75,000,000 of free cash flow and paid off $46,000,000 of debt. Our cash cushion, which is the free cash flow remaining after paying our private placement debt amortizations and distributions on our common and preferred units, was negative by only $13,000,000.
We continue to focus on and maintain robust liquidity and ended the quarter with $98,000,000 of cash and $100,000,000 of unused borrowing capacity. Demand and prices for metallurgical coal are up significantly from the beginning of the year. Resurgent steel demand driven by global economic recovery is more than offsetting continued pandemic related challenges for met coal. The ongoing China, Australia political and trade dispute appears to have been a positive for US producers as Chinese manufacturers realigned supply chains to procure met coal from other regions, allowing North American coal to make its way to destinations previously served by Australian producers. International benchmark prices for met coal have more than doubled since the beginning of the year amidst significant volatility, fluctuating within a range of $103 to $215 per ton.
NRP has yet to fully realize significant benefits from higher met prices, but we expect that will change in the coming months. As you will recall, most of our lessees met coal is sold pursuant to contracts of up to a year in duration. So we do not have much sensitivity to short term price movements. We expect most of those sales contracts to renew in the third and fourth quarters of this year at higher levels, which should provide upside to our met cash flows in the year ahead. Thermal coal demand and prices are also showing significant strength, with API two prices recently topping $140 per ton, up over 100% since the beginning of the year.
Increased electricity demand driven by a rebounding US economy and a strong winter burn are the primary drivers behind the price run up. The positive impact for us from recent thermal in price increases have been modest so far since the substantial majority of our thermal cash flows this year are fixed pursuant to our contract with Foresight Energy that went into effect as they emerged from bankruptcy in 02/2020. That fixed payment agreement terminates at the end of this year, and we will begin to receive traditional royalty payments starting January. As a result, we expect to benefit next year to the extent demand and prices for thermal coal remain strong. Turning to our investment in Ginger Wyoming.
Global demand for soda ash has shown significant improvement this year and is at pre pandemic levels. International spot prices have risen over 35% since the beginning of the year. Our joint venture in Green River Wyoming is operating at pre pandemic levels, and customer demand for our product is strong. While Ginger Wyoming's revenues and profitability have risen significantly over the course of the year, increases in ocean freight rates have been a drag on the bottom line. Looking forward, new lockdowns around the world due to COVID nineteen and supply chain constraints on auto production have the potential to weaken demand for soda ash in the coming months.
We expect soda ash pricing and logistics costs to remain volatile into 2022 as the market attempts to find a new equilibrium amidst a rapidly changing economic environment. In light of these uncertainties, we do not expect Wyoming management to resume regular cash distributions to us until market conditions stabilize. While the near term outlook is uncertain, we are quite optimistic about the intermediate and long term prospects for our soda ash investment. Our asset is one of the lowest cost producers of soda ash in the world, and we believe our operating partner, Ginger Resources, collectively with its parent, We Soda, is the best and most capable operator of natural soda ash in the world. These factors position us well to generate attractive margins and robust cash flows over the long term.
As mentioned on our last three earnings calls, we continue working to identify alternative revenue sources across our large portfolio of land, mineral, and timber assets. The types of opportunities we are exploring include the sequestration of carbon dioxide underground and in standing forest, and the generation of electricity using geothermal, solar, and wind energy. While the timing and likelihood of cash flows being realized from any of these activities is uncertain, we believe our large ownership footprint throughout The United States will provide opportunities to create value in this regard with minimal capital investment by NRP. The partnership's ability to continue generating free cash flow, reduce debt, and pay unitholder distributions during the COVID nineteen downturn demonstrates that we have the right strategy in place to create unitholder value. Since 02/2015, when we embarked on our strategy of delevering and derisking the partnership, NRP has paid down over $920,000,000 of debt, paid over $125,000,000 of common home unitholder distributions, and worked to solidify our capital structure and ensure strong liquidity.
Liquidity. We remain steadfast in our commitment to focus on maximizing unitholder value by continuing these efforts. And with that, I'll turn the call over to Chris to cover our financial results. Chris?
Thank you, Craig, and good morning, everyone. During the second quarter, we generated $13,000,000 of operating cash flow and $15,000,000 of net income. Our Coal Royalty and Other segment generated $32,000,000 of operating cash flow and $26,000,000 of net income during this period. Our coal royalty and other segment's second quarter free cash flow was flat quarter over quarter as improved coal royalty cash flow and stronger demand and pricing for coal in the February was offset by the timing of fixed payments from Foresight as they emerged from bankruptcy in the second quarter of last year. Our coal royalty and other segment second quarter net income improved 134,000,000 as compared to the prior year quarter, primarily because of $132,000,000 noncash asset impairment expense in the second quarter of last year resulting from weakened coal markets, were compounded by the COVID-nineteen pandemic.
Excluding asset impairments, net income improved slightly quarter over quarter as increases in coal royalty revenues and lower operating and maintenance expenses were partially offset by higher DD and A driven by increased production at certain Illinois Basin coal properties as well as certain onetime items in 2020. Metallurgical coal made up approximately 50% of our total coal royalty sales volumes and approximately 65% of our coal royalty revenue during the second quarter of twenty twenty one. Moving to our soda ash business segment. Net income in the second quarter of twenty twenty one improved $6,000,000 as compared to the previous year quarter, primarily due to strength in soda ash demand and increased sales volumes that were partially offset by increased ocean freight rates compared to the second year quarter of twenty twenty. Free cash flow in the second quarter of twenty twenty one was lower by $7,000,000 as compared to the prior year quarter due to General Wyoming's decision to suspend their quarterly distribution in August of twenty twenty.
As Craig mentioned earlier, and we have mentioned on previous earnings calls, General Wyoming continues to evaluate on a quarterly basis whether to reinstate the quarterly distribution, but we do not expect General Roman management to resume regular cash distributions to us until market conditions stabilize. We remain encouraged by General Roman's ability to operate its business safely and effectively, and we're confident in the long term earning power of our business. Our second quarter twenty twenty one corporate and financing segment costs were $1,000,000 lower, and cash used was reduced by $500,000 compared to last year's second quarter, primarily due to lower interest expense as a result of less debt less debt outstanding in 02/2021. Regarding distributions, in May, we paid a quarterly 45¢ per common unit distribution and a quarterly distribution of $7,700,000 to our preferred unitholders, onetwo of which in cash and onetwo in kind. Additionally, today, we announced a quarterly cash distribution of $0.45 per common unit and a quarterly distribution of 7,800,000.0 to our preferred unitholders, also to be paid one half in cash and one half in kind as required by our bond indenture.
These preferred unit distributions include interest on previously paid in kind units, which will also be paid one half in cash and one half in kind. As we mentioned last quarter, the indenture governing our bonds restricts us from paying more than one half of the quarterly distribution on our preferred units in cash if our consolidated leverage ratio exceeds 3.75 times. And as of 06/30/2021, our leverage ratio was 4.6 times. In addition, under the terms of our partnership agreement, if we have outstanding paid in kind preferred units in 2022, we would be required to temporarily suspend comm unit distributions until all paid in kind units have been redeemed. We expect our leverage ratio to now begin a sustained long term decline as we continue to pay down debt and plan to redeem all outstanding paid in kind units once our leverage ratio drops below 3.75 times.
And with that, I'll turn the call back over to the operator for questions.
Thank you. As a reminder, to ask a question, please press star one on your telephone keypad. To withdraw your question, press the pound key. Please stand by while we compile the queuing roster. Again, to ask a question, please press star one on your telephone keypad.
There is no further question this time. You may continue.
Thank you, operator. And thank you all for listening to our call and and reading our transcript. And thank you for your support with NRP. And, we look forward
to talking to you next
quarter. Best regards.
This concludes today's conference call. Thank you all for joining. You may now disconnect.