in the ordinary course of business , based on our evaluations of certain geologic trends and prospective economics , we have allowed certain lease acreage to expire and may allow additional acreage to expire in the future . if production is not established or we take no other action to extend the terms of the leases , licenses , or concessions , undeveloped acreage listed in the table below will expire over the next three years . we plan to continue the terms of many of these licenses and concession areas or retain leases through operational or administrative actions. .
what percent of net expiring acres in 2013 are foreign?
marketing and midstream our e&p segment includes activities related to the marketing and transportation of substantially all of our liquid hydrocarbon and natural gas production . these activities include the transportation of production to market centers , the sale of commodities to third parties and storage of production . we balance our various sales , storage and transportation positions through what we call supply optimization , which can include the purchase of commodities from third parties for resale . supply optimization serves to aggregate volumes in order to satisfy transportation commitments and to achieve flexibility within product types and delivery points . as discussed previously , we currently own and operate gathering systems and other midstream assets in some of our production areas . we are continually evaluating value-added investments in midstream infrastructure or in capacity in third-party systems . delivery commitments we have committed to deliver quantities of crude oil and natural gas to customers under a variety of contracts . as of december 31 , 2012 , those contracts for fixed and determinable amounts relate primarily to eagle ford liquid hydrocarbon production . a minimum of 54 mbbld is to be delivered at variable pricing through mid-2017 under two contracts . our current production rates and proved reserves related to the eagle ford shale are sufficient to meet these commitments , but the contracts also provide for a monetary shortfall penalty or delivery of third-party volumes . oil sands mining segment we hold a 20 percent non-operated interest in the aosp , an oil sands mining and upgrading joint venture located in alberta , canada . the joint venture produces bitumen from oil sands deposits in the athabasca region utilizing mining techniques and upgrades the bitumen to synthetic crude oils and vacuum gas oil . the aosp 2019s mining and extraction assets are located near fort mcmurray , alberta and include the muskeg river and the jackpine mines . gross design capacity of the combined mines is 255000 ( 51000 net to our interest ) barrels of bitumen per day . the aosp base and expansion 1 scotford upgrader is at fort saskatchewan , northeast of edmonton , alberta . as of december 31 , 2012 , we own or have rights to participate in developed and undeveloped leases totaling approximately 216000 gross ( 43000 net ) acres . the underlying developed leases are held for the duration of the project , with royalties payable to the province of alberta . the five year aosp expansion 1 was completed in 2011 . the jackpine mine commenced production under a phased start- up in the third quarter of 2010 and began supplying oil sands ore to the base processing facility in the fourth quarter of 2010 . the upgrader expansion was completed and commenced operations in the second quarter of 2011 . synthetic crude oil sales volumes for 2012 were 47 mbbld and net of royalty production was 41 mbbld . phase one of debottlenecking opportunities was approved in 2011 and is expected to be completed in the second quarter of 2013 . future expansions and additional debottlenecking opportunities remain under review with no formal approvals expected until 2014 . current aosp operations use established processes to mine oil sands deposits from an open-pit mine , extract the bitumen and upgrade it into synthetic crude oils . ore is mined using traditional truck and shovel mining techniques . the mined ore passes through primary crushers to reduce the ore chunks in size and is then sent to rotary breakers where the ore chunks are further reduced to smaller particles . the particles are combined with hot water to create slurry . the slurry moves through the extraction .