Gulf Crossing Pipeline Company LLC submits tariff filing per 154.204: Antero 2 to Tenaska 201 Cap Rel Neg Rate Agmt to be effective 5/1/2011 under RP11-2049 Filing Type : 570

March31,2011 Ms.KimberlyD.Bose,Secretary FederalEnergyRegulatoryCommission 888FirstStreet,N.E. Washington,D.C.20426 Re: TennesseeGasPipelineCompany GasQualityandInterchangeability DocketNo.RP11 DearMs.Bose: Pursuant to Section 4 of the Natural Gas Act (NGA) and Part 154 of the Regulations of the FederalEnergyRegulatoryCommission(Commission), 1 TennesseeGasPipelineCompany(Tennessee) herebysubmitsforfilingandacceptancetariffsheetstoitsFERCGasTariff,SixthRevisedVolumeNo.1 (Tariff),whichTariffsheetsareidentifiedinAppendixA.TennesseeproposesthattheTariffsheetsbe effectiveonMay1,2011. StatementofNature,ReasonsandBasisforFiling BACKGROUND TennesseeproposestorevisethegasqualityandinterchangeabilityprovisionsinArticleIIofthe GeneralTerms&Conditions(GT&C)ofitsTariff.Overthepastseveralyears,Tennesseehasexperienced significant diversification in the natural gas supplies entering its system. Receipts into Tennessee from unconventional shale plays, such as the Haynesville Shale in northern Louisiana and Texas and the Marcellus Shale in Pennsylvania, have been increasing, while receipts from conventional sources in the GulfofMexicoandSouthTexashavebeendeclining.Tennesseehasalsoexperiencedasurgeinsupplies from the Rocky Mountains entering its system at the interconnection in Ohio with Rockies Express PipelineLLCandfromtheAppalachianSupplyBasin.Liquefiednaturalgas(LNG)terminalsontheGulf Coast may also contribute significant supplies of regasified LNG to the Tennessee system. Because the compositionofgasfromeachofthesesourcesofsupplyisdifferentandchangesingascompositionmay affect end users, Tennessee and its customers have discussed the need to update the gas quality and interchangeability provisions in its Tariff. In crafting the proposed revisions to the gas quality and interchangeabilityprovisions,Tennesseehassoughttodevelopaflexibleapproachthatseekstoaddress the gas quality and interchangeability concerns of end users while at the same time maximizing the suppliesavailabletotheTennesseesystem. 1 18C.F.R.Part154. TennesseeGasPipeline 1001LouisianaHouston,Texas77002 P.O.Box2511Houston,Texas772522511 Tel7134202131 Ms.KimberlyD.Bose,Secretary FederalEnergyRegulatoryCommission March31,2011 Page2 COMMISSIONPOLICY IndevelopingitsgasqualityandinterchangeabilityTariffproposal,Tennesseehasadheredtothe Commissions guidance in the Policy Statement on Provisions Governing Natural Gas Quality and Interchangeability in Interstate Natural Gas Pipeline Company Tariffs (Policy Statement). 2 The Policy Statement sets forth five general principles to guide pipelines in developing tariff provisions to address gas quality and interchangeability concerns. Tennessees proposal is consistent with each of these principles. First, Tennessees proposal establishes gas quality and interchangeability provisions in TennesseesTariff.Second,Tennesseesproposalisdesignedtomaximizeitsflexibilitytoacceptnatural gas supplies at receipt points while maintaining its ability to manage gas quality and interchangeability within acceptable