PUBLISH
UNITED STATES COURT OF APPEALS
FOR THE TENTH CIRCUIT

________________ _________________ MARALEX RESOURCES, INC., a Colorado corporation; ALEXIS M. O'HARE; MARY C. O'HARE, Plaintiffs - Appellants,

v. DAVID BARNHARDT, in his official capacity as Acting Secretary of the United States Department of the Interior; THE UNITED STATES DEPARTMENT OF INTERIOR; THE UNITED STATES OF AMERICA,  Defendants - Appellees. No. 17-1421

________________ _________________ Appeal from the United States District Court for the District of Colorado (D.C. No. 1:15-CV-01893-CMA)

________________ _________________ William E. Zimsky, Abadie & Sch ill, PC, Durango, Colorado, appe aring for the Appellants. Tamara N. Rountree, Attorney, Envir onmental and Natural Resourc es Division, United States Department of Justice, W ashington, DC (Jeffrey H. Wood, Acting Assistant Attorney General, and Eric Grant , Deputy Assistant Attorney Gen eral, United States Department of Justice, Washington, DC; William Lazarus and JohnL. Smeltzer, Attorneys, Environmental and Natural Resources Division, United States Department of Justice, Washington, DC; and Ph ilip C. Lowe, Rocky Mountain Reg ional Solicitor’s

 In accordance with Fed. R. App. P . 43(c)(2), David Barnhardt i s substituted for Ryan Zinke, as the re spondent in this action. FILED United States Court of Appeals Tenth Circuit 

### January 18, 2019
Elisabeth A. Shumaker Clerk of Court2 Office, Department of the Interi or, Lakewood, Col orado, with he r on the brief), appearing for the Appellee.

________________ _________________ Before BRISCOE , LUCERO , and MATHESON , Circuit Judges.

________________ _________________ BRISCOE , Circuit Judge.

________________ _________________ Plaintiffs Maralex Resources, Inc . (Maralex), Alexis O’Hare and Mary C. O’Hare (the O’Hares) filed this action against the Secretary of the Department of the Interior (Secretary), the Depart ment of the Interior, and the U nited States seeking review of a decision of the Inter ior Board of Land Appeals (IBL A) upholding four Notices of Incidents of Noncomplia nce that were issued by the B ureau of Land Management’s (BLM’s) Tres Rios F ield Office to Maralex for fail ing to allow a BLM representative to access cert ain oil and gas lease sites op erated by Maralex on land owned by the O’Hares. The d istrict court affirmed the IBL A’s decision. Plaintiffs now appeal. Exercising jurisdiction pursuant to 28 U.S.C. § 1291, we conclu de that the BLM, in issuing the Notices of In cidents of Noncompliance, lack ed authority to require plaintiffs to provide BLM with a key to a lease site on privately-owned land or to allow the BLM to install i ts own locks on the gates to su ch lease site. Consequently, we reverse and rema nd to the district court with instructions to enter judgment in favor of plaintiffs on this “key orlock” issue.3 I The Parcel and its component Tracts At issue in this cas e is a 320-acre parcel of land (the Parcel) that is located in the S1/2 of Section 35, Township 34 South, Range 7 West in La P lata County in southwestern Colorado. The Par cel, which is comprised of 240 a cres of private surface/mineral estate and 80 acr es of Indian su rface/mineral e state, lies over the Ignacio Blanco gas field and the Fruitland coal formation. The O’Hares own the surface and mineral estate in a 120-acre tr act of land in the SW1/4SE1/4 and E1/2SW1/4 of the Parcel (the O’Hare Tract). The Southern Ute Indian Tribe (Tribe) holds the s urface and mineral estate in th e W1/2SW1/4 of the Parcel (the Tribe Tract). The r emainder of the Parcel (the Rem ainder Tract)—the N1/2SE1/4 and SE1/4SE1/4—is priv ately-owned by the O’Hare famil y, J. Elmer and Wanda Lee Kenner, and Irma Rowse. The leases of the Tracts On June 6, 1974, the Tribe, acti ng pursuant to the Indian Miner al Leasing Act of 1938, 25 U.S.C. §§ 396a-396g (2012), issued to Sun Oil Compa ny an Indian oil and gas lease, Mining Lease Cont ract No. MOO-C-1420-1531, for i ts mineral estate in the Tribe Tract. Amoco Produc tion Company (Amoco) later too k over as the lessee.4 On April 28, 1995, the O’Hares issued to Maralex 1 a private oil and gas lease for the O’Hare Tract. SG Intere sts III, Ltd. (SG III) later jo ined Maralex as colessee. The O’Hares, Kenners, and Rowse issued three private oil and ga s leases covering the Remainder Tract. SG III and Maralex became the le ssees of those leases. The Communitization Agreement In 1996, all of the parties (SG II I, Maralex, the Tribe, the O’ Hares, Kenners, and Rowe) “communitized” their co al and gas interests in the Pa rcel under the terms of a written agreement. More sp ecifically, in a written Commun itization Agreement (CA) dated May 1, 1996, the par ties agreed to develop and opera te the Parcel “as an entirety, with the understanding and agreement . . . that all C ommunitized Substances produced therefrom [would] be a llocated among the leaseholds co mprising said area in the proportion that the acreag e interest of each leasehold b ears to the entire acreage interest committed to [th e CA].” Aplt. App. at 3. The CA further stated, in pertinent part, that “[t]he r oyalties payable on Communitized S ubstances allocated to the individual leases c omprising the [Tract] . . . shall be det ermined and paid on the basis prescribed in each of th e individual leases.” Id. Two other provisions of the CA a re relevant to this case. Firs t, the CA stated: “This agreement shall be subjec t to all applicable Federal and State laws or executive

1 According to the record on appe al, Mary O’Hare is the presiden t of Maralex. Aplt. App. at 8.5 orders, rules and regulations . . . .” Id. at 4. In addition, the CA stated: “It is agreed between the Parties Hereto that t he Secretary of the Interior, or his duly Authorized Officer, shall have the right o f supervision over all operation s within the Communitized Area to the extent sa me includes the oil and gas l ease(s) under which the . . . Tribe is le ssor and insofar as governed by applicable oil and gas regulations of the Department of I nterior.” Id. at 5. The CA was approved by the Tribe and the Bureau of Indian Affai rs (BIA) effective May 1, 1996. The wells operating under the CA There are four wells associatedwith the CA and arising from th e underlying leases, all of which are operate d by Maralex. The four wells a re physically situated in two areas on the O’Hares’ pri vate surface estate in the O’Ha re Tract. Each such area is enclosed by a fence and a locked gate. All four of the wells are producing “both fee and Tribal minerals” f rom the Fruitland coal formatio n. Id. at 32. Although the oil and gas at issu e is produced from private mine ral interests and from wells situated on private surface estates, such production is, under the terms of the CA, allocated to all of the oil and gas interests, including th at of the Tribe, as the owner of record title to the mine ral estate in the Tribe’s Sect ion of the Parcel. BLM’s attempt to inspect the wells On February 11, 2013, Gabriel T rujillo, a Petroleum Engineering Technician employed by the BLM, sent an ema il to Maralex stating that he p lanned to inspect the four wells. On February 12, 20 13, Christi Reid, a Maralex empl oyee, responded by6 email, noted that the wells were situated “on Mick ey O’Hare’s p roperty,” and stated that she envisioned “problems w ith him granting access” to Truj illo. Id. at 18. One day later, on February 13, 20 13, Reid emailed Trujillo again, s tating: “I talked to Mickey O’Hare and let him know that you want to inspect the . . . wells. He wants to talk to you directly . . . .” Id. On February 22, 2013, T rujillo drove to the Parcel in an attemp t to examine the wells. Upon arrival, Truji llo found that there was a locke d gate that prevented him from examining the wells. That same day, Trujillo spoke by phone with Mickey O’Hare. O’Hare inform ed Trujillo that he h ad no right to inspe ct the wells because O’Hare owned both the su rface and mineral rights. BLM’s issuance of INCs to Maralex On February 26, 2013, Trujillo completed four official BLM form s entitled “Notice of Incidents of Noncompliance” (INC). Id. at 23. The INCs noted that Trujillo had attempted unsuccessfully to access the wells on Fe bruary 22, 2013. The INCs, which were sent to Maralex , alleged that Maralex was in v iolation of 43 C.F.R. § 3162.1(b), and they gave Marale x until March 25, 2013, to pro vide Trujillo and the BLM with access to the wells. In the “Remarks” section of the INCs, Trujillo stated: “For corrective acti on, I will need a key to access the locatio n or be able to put a BLM lock in with it.” Id. at 24. Maralex’s administrative appeal of the INCs On March 27, 2013, a law firm re presenting Maralex and the O’Ha res sent a letter to BLM appealing the fourINCs. The letter asserted tha t the BLM had7 misinterpreted its authority to inspect oil and gas wells locat ed on private land. More specifically, the lette r asserted that the BLM “ha[d] limited a uthority to inspect facilities on Fee Tracts” and th at the applicable regulations “ only allow[ed] annual inspections” of such wells. Id . at 33. The letter also assert ed that “there [wa]s no statutory authority nor . . . any legitimate justification for giving the BLM unbridled discretion to search the faciliti es at issue in order to ensure that there [wa]s adequate site security measurement and that Maralex [wa]s properly measu ring the production and operation of the wells.” Id. “Thus,” the letter asserted, “BLM’s request for a key to any gates to conduct insp ections [wa]s violative of Mara lex’s constitutionally guaranteed protection against unr easonable searches under the F ourth Amendment.” Id. Lastly, the letter asserted that “there [wa]s no legal aut hority for the BLM’s demand for unfettered access to t he O’Hare’s su rface.” Id. An d the letter argued that “[i]f the BLM was entitled to unf ettered right to access O’Hare ’s property under Section 3162.1(b), it would cons titute a regulatory taking of O ’Hare’s property in violation of O’Hare’s property ri ghts as guarantee [sic] by the takings clause of the Fifth Amendment.” Id. at 34. On April 10, 2013, the BLM notif ied Maralex’s counsel that it w as treating the March 27, 2013 letter “as a reque st for State Director’s review (SDR) . . . under 43 CFR 3165.3.” Id. at 88. On July 9, 2013, the BLM’s Deput y State Director, Energy, Lands , and Minerals, Colorado State Office , sent a letter to Maralex’s cou nsel responding to each point raised by Maralex’s counsel. The letter disagreed t hat the applicable8 regulations allowed only for “a nnual inspections for fee tracts in a CA.” Id. at 90. Rather, the letter asse rted, the “inspected annually” language in the regulation merely established a minimum standard a s to what was to be accomplishe d. Id. As for its authority to conduct inspections o f the wells, the BLM noted th at Section 101(b) of the Federal Oi l and Gas Royalty Management Ac t of 1982 (FOGRMA) provides that, “ Authorized and properly identified representatives of the Secretary may without advance notice, enter upon, travel across and inspect le ase sites on Federa l or Indian lands and may obtain from the operator i mmediate access to secured facilities on such lease sites, for the pur pose of making any inspection or investigation for determining whethe r there is compliance with the requirements of the minearal [sic] leasing laws and this Act.” Id. at 90-91 (italics in original) . The BLM in turn stated tha t “[s]ince the subject wells’ production is subject to a federal CA and the governmentreceives a portion of the production’s royalty, the BLM is responsible for assuring p roduction accountability” and that “[t]his i ncludes inspections for site security, proper handling, measurement and reporting of pr oduction and prot ection against product theft.” Id. at 91. “Therefore,” the letter state d, “BLM must be allowed to pe rform the production related inspection which necessi tates physical acc ess to the su bject wells and their associated facilities without advance notice. ” Id. In a secti on entitled “Decision,” the letter stated: Upon review, the four INCs cove ring denied access to the subjec t wells were properly issued and are upheld. The stay of enforce ment action granted in our April 10, 2013, letter to Maralex is here by lifted. Maralex must provide the BLM T res Rios Field Office access without advance notice as require d by the INCs and the regulati ons. If Maralex chooses not t o provide access as required, Maralex will be subject to assessments pursuant to 43 CFR 3163.1. In addition further9 non-compliance shall result in proposed civil penalties pursuan t to 43 CFR 3163.2(e)(1). Id. at 93. On August 20, 2013, Maralex’s c ounsel sent the BLM a notice of appeal of the July 9, 2013 decision. Id. at 97. Maralex’s counsel followed that up by filing with the IBLA a Statement of Reasons for Appeal. Id. at 98. The St atement of Reasons argued that the regulation relied on by the BLM, 43 C.F.R. § 31 62.1(b), applies only “to Federal and Indian lease sites,” and that “there is no stat utory authority to support the BLM’s suggestion that it ha s the right to conduct warrantle ss searches of Maralex’s facilities. ” Id. at 113. “Thus,” the Statement of R easons asserted, “BLM’s request violates Maralex’s ri ght not to be subject to unreasonable searches as guaranteed by the Fourth Amendmen t.” Id. Lastly, the Statemen t of Reasons asserted that “if the BLM does have the statutory and regulatory authority to access the O’Hare’s Fee Tract at any time, such authority would consti tute a regulatory taking of the O’Hare’s property in violation of their due proce ss rights under the Fifth Amendment.” Id. On July 10, 2015, the IBLA issued a written decision affirming the BLM’s July 9, 2013 decision. In doing so, the IBLA did not address w hether plaintiffs were required to provide the BLM with a key or allow the BLM to inst all its own locks on Maralex’s gates, nor did the IBL A address plaintiffs’ constitut ional arguments. The district court proceedings10 On September 1, 2015, Maralex a nd the O’Hares initiated these p roceedings by filing a complaint in federal d istrict court against the Sec retary, the Department of the Interior, and the United Stat es. The complaint sought reve rsal of the IBLA’s decision, as well as declaratory relief. On October 19, 2017, the district court issued an order affirmi ng the IBLA’s determination. Plaintiffs now appeal.
II Plaintiffs raise two issues on a ppeal: (1) whether they waived their argument that the BLM lacked authority to require them to provide the BL M with keys to the locked gates on the O’ Hares’ private propert y or, alternatively , to allow the BLM to place its own locks on those gate s; and (2) whether the BLM has statutory or regulatory authority to require p laintiffs to provide the BLM w ith keys to locked gates on privately-owned lands o r, alternatively, to allow the BLM to place its own locks on such gates. 2 As discussed in more detail b elow, whether plaintiffs waived their argument is a close questi on, but assuming they did, we n evertheless exercise discretion to address the underlyi ng issue. We in turn conclud e that BLM lacked authority to impose the “k ey or lock” requirement. Did plaintiffs waive their argument that the BLM lacked authority to require them to prov ide keys to their locked gates or to allow the BLM to place its own locks on those gates?

2 Until recently, plain tiffs asserted three additional issues on appeal, including Fourth and Fifth Amendment challe nges to the inspection protoco l advocated by the BLM. At oral argument, however , plaintiffs abandoned those iss ues. Consequently, we do not address them.11 As noted, plaintiffs first argue that the district court erred in concluding that they waived their argument that the BLM lacked authority to req uire them to provide the BLM with keys to locked gate s or to allow the BLM to place its own locks on those gates. The district court concluded that plaintiffs “did not present to the IBLA this particular argument that t he BLM’s corrective action excee ded its authority.” Aplt. App. at 207-08. The districtcourt in turn concluded “th at Plaintiffs waived this argument for purposes of this ap peal and [it] decline[d] to con sider it.” Id. at 208. To resolve this issue, we begi n by turning to the record. Plai ntiffs, in their initial appeal of the INCs, “claim[ed] that BLM ha[d] no statut ory authority or legitimate justification giving the BLM unbridled discretion to search the subject well facilities in order to ensu re site security and proper mea surement” and that, consequently, “the BLM’s request for a key to any gates to conduct inspections [wa]s in violation of Maralex’s consti tutionally guaranteed protectio n against unreasonable searches under the Fourth Ame ndment.” Aplt. App. at 90. In their appeal to the IBLA fro m the State Director’s decision denying their initial appeal, plaintiffs argued , in pertinent part, that “the re [wa]s no statutory authority nor . . . any legitimate justification for giving the BLM unbridled discretion to search the facili ties at issue at any ti me and without notic e,” and that, consequently, “BLM’s request fora key to any gates to conduct unannounced inspections [wa]s violative of Maralex’s constitutionally guara nteed protection against unreasonable searches unde r the Fourth Amendment.” Id. at 102. Plaintiffs further argued that “there [wa] s no statutory support for warra ntless, unannounced12 inspections of [the] Fee Tracts ,” and thus the B LM could not “r ely on” its own regulations “for conducting unann ounced, warrantless searches o f the sites at issue.” Id. at 107–08. Plaintiffs also ar gued that “Paragraph 13” of t he CA “does not provide the BLM with the unlimited rightto conduct inspections withoutadvance notice nor does it form the basis for givi ng the BLM a key to have unlimit ed physical access to the wells and related facilitie s on Fee Tracts, which is applic able only to Federal and Indian lease sites.” Id. at 112 . Lastly, the plaintiffs chall enged the State Director’s rejection of “the O’Hare’s [sic] assertion that forcing them to supply the BLM with a key to a lock to allow the BLM to have physical access to theirsurface property for unannounced inspections of Marale x’s wells and related faciliti es located on the O’Hare’s [sic] surface constitute [d] an unauthorized takings un der the Fifth Amendment.” Id. at 112-13. In our view, it is a close ques tion whether plai ntiffs presente d their argument to the IBLA that BLM exceeded its statutory and regulatory auth ority by requiring a key or lock in the INCs. On th e one hand, plaintiffs clearly a rgued, as part of their Fourth Amendment challenge, that the BLM lacked both statutory and regulatory authority to impose the key/lockrequirement. On the other han d, plaintiffs expressly asserted before the IBLA that it lacked authority to address th eir Fourth Amendment challenge and they asked the IBLA not to consider it. Even assuming, however, that plai ntiffs failed to properly pres ent to the IBLA their argument that t he key/lock requirement exceeded the BLM’s statutory and regulatory authority, we neverthe less choose to exercise our di scretion to address that13 issue. 3 See U.S. Nat’l Bank of Oregon v . Indep. Ins. Agents of Am., I nc., 508 U.S. 439, 447–48 (1993) ( discussing authority o f appellate court to address potentially waived issue). We have held, alb eit in a slightly different co ntext, that we may depart from general waiver princ iples “particularly when we are presented with a strictly legal question, the pr oper resolution of which is beyo nd doubt or when manifest injustice would otherw ise result.” Daigle v. Shell Oi l Co., 972 F.2d 1527, 1539 (10th Cir. 1992). Further, in considering whether to addr ess an alternative theory, we take into account (1) “whether the ground was fully briefed and argued here and below,” (2) “whether t he parties have had a fair opportunity to develop the factual record,” and (3) “wheth er, in light of factual findings to which we defer or uncontested facts, our decision w ould involve onl y questions of law.” Elkins v. Comfort, 392 F.3d 1159, 1162 ( 10th Cir. 2004) (citations omitte d). In this case, the issue of the BL M’s statutory and regulatory a uthority has been fully briefed and argued in this court by both sides. Further, the factual record is essentially undisputed and, thus, we are presented with only a question of law. Lastly, and perhaps most impor tantly, the BLM has indicated its intention to enforce the key/lock requirement at the conclusion of this litigation. On October 22, 2018,

3 We are not aware of, nor has t he BLM cited to, any authority h olding that preservation of the issue before t he IBLA is a jurisdictional p rerequisite. See Air Courier Conference of Am. v. Am. P ostal Workers Union AFL-CIO, 498 U.S. 517, 523 n.3 (1991) (“The judicial r eview provisions of the APA are not jurisdictional . . . .”); Chissoe v. Zinke, 725 F. A pp’x 614, 621 (10th Cir. 2018) ( stating that “judicial exhaustion requirements under the APA are prudential only.”); V ietnam Veterans of Am. v. Shinseki, 599 F.3d 654, 6 61 (D.C. Cir. 2010) (“We think the proposition that the review provisions of the APA are not jurisdictional is now firmly established.”).14 we issued an order to show cause directing the parties to addre ss, in pertinent part, the question of whether the BLM was continuing to require Maral ex to provide the BLM with a key to the lock on th e O’Hares’ gate or to allow the BLM to place its own lock on the gate. On Decembe r 18, 2018, defendants respond ed that, indeed, “BLM continues to require Maralex to either provide the agency with a key to the lock on the O’Hares’ gate or all ow BLM to place its own lock on the gate.” Aple. Resp. to Order to Show Cause at 2. Defendants asserted that, “ [i]n the absence of compliance with the [key/lock re quirement] in the INCs, Mr. O’H are may refuse BLM access to the wells at any tim e, as he did in February 2013 (which led to BLM’s issuance of the INCs).” Id. at 3. Thus, despite the fact that the INCs were issued nearly six years ago, it is clear that the BLM intends to enfor ce the key/lock requirement once this litigation ends. For this reason, we con clude that the interests of justice are best served if we address the merits of plaintif fs’ argument that BLM lacks statutory and regulatory authority to impose the key/lockrequirement. Does the BLM have authority to require a landowner or operator to provide the BLM with keys to the landowner’ s locked gates or allow the BLM to place its own locks on the landowner’s gates? We now turn to the merits of p laintiffs’ argument. Plaintiffs assert that, even assuming some statutory or regu latory authority exists for the BLM to conduct inspections on fee lands without a dvanced notice, “there are li mits to such inspections.” Aplt. Br. at 40. P laintiffs point to the langua ge of 30 U.S.C. § 1718 to support their position. Section 1718, plaintiffs note, “limits the right to enter upon, travel across and inspect lease sites to not only ‘authorized’ representatives of the15 Secretary, but to representatives that are ‘properly identified .’” Id. And, plaintiffs argue, “[b]ecause the landowner a nd the operator have the rightto ensure that the representative is properly ident ified, the BLM cannot force eit her the landowner or the operator to provide a key t o the landowner’s locked gates o r be forced to allow the BLM to place a lock on the landowner’s locked gates since b y doing so neither the landowner nor operator will b e able to check the identifica tion of the person(s) entering upon, travelling across , and/or inspecting the facilit ies.” Id. at 40-41. Lastly, plaintiffs argue that “[a] ll that is required of the op erator under Section 1718(b) is to provide ‘immediat e access to secure d facilities’ to a properly identified representative of the Secretary. ” Id. at 41. This means, plai ntiffs argue, that “if the operator is on site at the time o f the inspection, it is requir ed to open any gates or otherwise secured facilities” a nd “[i]f the operator is not on the lease site when the authorized, properly identified representative arrives at the l ease site, then the operator is required to go to the lease site and provide immedi ate access.” Id. Defendants argue, in response, tha t “the INCs’ corrective actio n requiring Plaintiffs to provide BLM with key or lock access is permissibl e under the statute and the regulations.” Aple. Br. at 39. In particular, defendants assert that “FOGRMA and its implementing regulations provide that any person who fa ils to allow authorized inspections is liable for penalties, which may not b e applied if the liable person takes the prescribed corr ective action within the requir ed timeframe.” Id. a) Standard of review16 Although this is an appeal from the district court’s decision, we accord no particular deference to that decision. Instead, we conduct ourown independent review of the agency’s decision. Exxon Mobil Oil Corp. v. Nort on, 346 F.3d 1244, 1248 (10th Cir. 2003). Under the Administrative Procedures Act , we will “set aside agency’s action if it is arbit rary, capricious, an abuse of dis cretion, or otherwise not in accordance with law.” Utah E nvtl. Cong. v. Bosworth, 439 F. 3d 1184, 1188 (10th Cir. 2006) (internal quotations o mitted); see 5 U.S.C. § 706(2) (A). When reviewing an agency’s interp retation of a statute it admin isters, we first determine whether Congress has di rectly spoken to the precise i ssue. See Chevron, U.S.A., Inc. v. Nat. Res. Def. Council, Inc., 467 U.S. 837, 842 (1984); Cliffs Synfuel Corp. v. Norton, 291 F.3d 1250, 1257 (10th Cir . 2002). “If the intent of Congress is clear, that is the end of the m atter; for the court . . . must give effect to the unambiguously expressed intent o f Congress.” Chevron, 467 U.S. at 842–43. If, however, the statute is silent o r ambiguous on the issue in que stion, we do not impose our own construction on the stat ute, but rather ascertain wheth er the agency’s interpretation is a p ermissible constructi on of the statute. I d. at 843. If it is, we defer to that interpretation. Id. at 844. Our review of federal regu lations is similar. “In the usual course, when an agency is authorized by Congress to issue regulations and promulgates a regulation interp reting a statute it enforces, th e interpretation receives deference if the statu te is ambiguous and if the agency’s interpretation is reasonable.” Encino Motorcars, LLC v. Navarro , 136 S. Ct. 2117, 2124 (2016). “This principle is implemented by the two-step analy sis set forth in Chevron.” Id . “At the first step, a17 court must determine whether C ongress has ‘directly spoken to t he precise question at issue.” Encino, 136 S. Ct. a t 2124 (quoting Chevron, 467 U. S. at 842). “If the intent of Congress is clear, that is the end of the matter; forthe court, as well as the agency, must give effect to the unambiguously expressed intent of Congress.” 4 Chevron, 467 U.S. at 842-43. “ If not, then at the second step the court must defer to the agency’s interpretation if it is ‘reasonable.’” Encino, 13 6 S. Ct. at 2125 (quoting Chevron, 467 U.S. at 844). “It i s well established that an age ncy’s interpretation need not be the only possible read ing of a regulation—or even t he best one—to prevail.” Decker v. Nw. Envtl. D ef. Ctr., 568 U.S. 597, 613 (2 013). “When an agency interprets its own regula tion, the Court, as a general rule, defers to it unless that interpretation is plainly erroneous or inconsistent with t he regulation.” Id. (quotation marks omitted). b) Analysis We begin our analysis by briefl y examining the overall statutory and regulatory scheme for inspections of oil and gas lease sites th at implicate Indian

4 At the first step of the Chevr on analysis, “we must giv[e] all undefined terms their ordinary meaning.’” Nat’l Credit Union Admin. Bd. v. Nom ura Home Equity Loan, Inc., 764 F.3d 1199, 1227 ( 10th Cir. 2014) (quoting Fed. Hous. Fin. Agency v. UBS Americas Inc., 712 F.3d 136 , 141 (2d Cir. 2013)). “We may consult a dictionary to determine the plai n meaning of a term” and may “a lso take into account the broader context of the statu te as a whole when ascertaining the meaning of a particular provision.” Conrad v. Phone Directories Co., 585 F. 3d 1376, 1381 (10th Cir. 2009) (quotation marks and citation omitted).18 mineral interests. In § 1702 of FOGRMA, Congress set forth the following definitions that are relevant t o understanding the substantive provisions of the Act: (1) “Federal land” mean s all land and intere sts in land owned b y the United States which are subject to the mineral leasing laws, in cluding mineral resources or mineral esta tes reserved to the United Sta tes in the conveyance of a surface or nonmineral estate;
· · · (3) “Indian lands” means any la nds or interest in lands of an I ndian tribe or an Indian allottee held in trust by the United States or whi ch is subject to Federal restriction ag ainst alienation or which is a dministered by the United States pursuant to section 14(g) of Public Law 92 -203 [43 USC § 1613(g)], as amended, inc luding mineral resources and min eral estates reserved to an Indian tri be or an Indian allottee in th e conveyance of a surface or nonmin eral estate, except that such term does not include any lands subject to the provisions of section 3 of the Act of June 28, 1906 (34 Stat. 539) [unclassified];
· · · (5) “lease” means any contract , profit-share arrangement, jointventure, or other agreement issued or approved by the United States unde r a mineral leasing law that authoriz es exploration for, extraction of, or removal of oil or gas; (6) “lease site” means any lands or submerged lands, including the surface of a severed mineral esta te, on which exploration for, or extraction or removal of, oil or g as is authorized pursuant to a lease;
· · · 30 U.S.C. § 1702(1), (3), (5), (6). In our view, the plain language o f the statutory definition of “lease” includes communitization agreements approve d by the United States, such as the one at issue in this case. More sp ecifically, a commun itization agreement i s a “contract” or “other agreement” that, dependi ng upon the circumstances, has b een “approved by the United States under a mineral leasing law,” i.e., federal l aw governing mineral rights on Indian and trust land, “ that authorizes exploration f or, extraction of, or19 removal of oil or gas.” 5 Thus, the statutory definition of “lease site” necessarily includes any lands, including priv ately-owned lands, on which e xploration for and extraction of oil and gas is occu rring pursuant to a communitiz ation agreement. Section 1718 of FOGRMA, entitled “I nspection,” provides in pert inent part as follows: (b) Inspection of lease sites for co mpliance with mineral leasing l aws and 30 USCS §§ 1701 et seq . Authorized and properly identified representatives of the Secretar y may without advance notice, en ter upon, travel across and insp ect lease sites on Federal or Indian land s and may obtain from the operator immediat e access to secu red facilities on such lease sites, for the purpose of making an y inspection or invest igation for determining whether th ere is compliance with the requirements o f the mineral leasing laws and this A ct. The Secretary shall develop guidelines setting forth the cove rage and the frequency of such inspections. 30 U.S.C. §1718(b). Although § 1718(b) incorporat es the statut ory phrase “lease sites,” it proceeds to limit the scope of that phrase by author izing BLM representatives to, “without adva nce notice, enter upon, travel across and inspect” lease sites that exist “on Fede ral or Indian lands,” i.e., non- fee lands owned by the United States or held in trust by the United States for a tribe , and that arise out of

5 Neither the IBLA nor the BLM ha ve expressly adopted this broad definition of “lease.” Instead, the IBLA in terpreted the identically-word ed regulatory definition of the term “lease site” to incl ude more than “Federal or India n lease sites,” and also concluded that the identically-w orded regulatory definition of the term “lease” was not incorporated into the regul atory phrase “lease site.” Aplt . App. at 170, 174. We reject this latter conclusion as inconsistent with the statutor y language and normal rules of statutory construction . In particular, “it is a norma l rule of statutory construction that identical words used in different parts of th e same act are intended to have the same meaning,” and we see no evidence that Congress intended for the term “lease,” as used in the ter m “lease site,” to carry a diff erent meaning. Pereira v. Sessions, 138 S. Ct. 2105, 2115 (2018).20 contracts or agreements issued or approved by the United States . Further, the statute is silent with respect to how, i f at all, BLM representatives m ay access lease sites on privately-owned lands. Defendants concede that “Congres s did not expressly address the application of Section 1718(b) inspection au thority to fee lands committed to communitization agreements.” Aple. Br. at 15. But, defendants argue, “[g]iven that ambiguity, BLM reasonably exercised its delegat ed rulemaking authority to incl ude the inspection of fee lands that, like the O’Hare s’, are subject to a communitiza tion agreement that was approved by the Department and i nvolves Indian lands where the affected tribe shares in the production and royalties of the oil and gas operation.” Id. Defendants’ arguments hinge on th e threshold question of whethe r § 1718(b) is ambiguous or not. A statute is “a mbiguous if it is reasonably susceptible to more than one interpretation or capab le of being understood in two o r more possible senses or ways.” Nat’l Credit Union Ad min. Bd. v. Nomura Home Equity Loan, Inc., 764 F.3d 1199, 1226 (10th Cir. 2014) (quotations and citations omit ted); see Chickasaw Nation v. United States, 534 U.S . 84, 90 (2001). Although it m ay be reasonable from a policy standpoint for the BLM to have authority to inspect fe e lands that are subject to a communitization agreement approved by the United States, § 1718(b) simply is not ambiguous and thus does not p rovide the BLM with any author ity to exercise its delegated rulemaking authority on that issue. As noted, § 1718 (b) quite clearly limits the BLM’s inspection authority t o lease sites on federal and In dian lands.21 To be sure, § 1718(b) is silent w ith respect to inspections of lease sites on fee lands, but that silence does not r ender the statute ambiguous. See Spring Creek Expl. & Prod. Co. v. Hess Bakken Inv., II, LLC, 887 F.3d 1003, 1018 ( 10th Cir. 2018) (“silence is not ambiguity”). Whe n the Supreme Court has discu ssed the exercise of agency discretion “‘in the inter stices created by statutory sil ence,’” it has done so only when “considering undefined terms in a statute or statutor y directive to perform a specific task without giving de tailed instructions.” Marlow v . New Food Guy, Inc., 861 F.3d 1157, 1162 ( 10th Cir. 2017) (quo ting Util. Air Regulat ory Grp. v. EPA, 134 S. Ct. 2427, 2445 (2014) (internal quotation marks omitted)). And that is simply not the case with § 1718(b). As noted , § 1718(b) plainly focuses o n lease sites “on Federal or Indian lands” and does not otherwise leave any terms or statutory directives undefined. For these reasons then, we conc lude that § 1718( b) does not aff ord the BLM with authority to inspect lease s ites on privately-owned lands. Thus, we must look elsewhere to determine whether any authority exists for the BLM ’s proposed inspections of the wells in this case. The Secretary has issued regula tions implementing the various s tatutory directives outlined by Congress in FOGRMA. To begin with, 43 C .F.R. § 3161.1(b)

states: The regulations in this part a nd 43 CFR part 3170, including subparts 3173, 3174, and 3175, relating to site security, measurement of oil and gas, reporting of production a nd operations, and assessments or penalties for non-compliance with such requirements, are applicable to all wells and facilities on State or privately owned la nds committed to a22 unit or communitization agreement, which include Federal or Indian lease interests , notwithstanding any pr ovision of a unit or communitization agreement to the contrary. 43 C.F.R. § 3161.1(b) (emphasis added). In turn, 43 C.F.R. § 3161.3, ent itled “Inspections,” states: (a) The authorized officer shall establish proce dures to ensure that each Federal and Indian lease site whi ch is producing or is expected to produce significant quantities of o il or gas in any year or whi ch has a history of noncompliance with applicable provisions of law or regulations, lease terms, orders or directives s hall be inspect ed at least once annually. Similarly, each leas e site on non-Federal or no n-Indian lands subject to a for mal agreement such as a unit or communiti zation agreement which has been approved by the Department of the Inte rior and in which the United States o r the Indian lessors share in p roduction shall be inspected annually whene ver any of the foregoing crite ria are applicable. (b) In accomplishing the inspect ions, the authorized officer ma y utilize Bureau personnel, may enter int o cooperative agreements with St ates or Indian Tribes, may delegate the inspection authority to any Sta te, or may contract with any non-Federa l Government entities. Any cooperative agreement, delegati on or contractual arrangement sh all not be effective without concurrence of the Secretary and shall inc lude applicable provisions of the Fede ral Oil and Gas Royalty Manage ment Act. 43 C.F.R. § 3163.3(a) and (b). 6 Lastly, 43 C.F.R. § 3162.1, which discusses “General requiremen ts” for operating rights owners a nd operators, states: (a) The operating rights owner oroperator, as appropriate, sha ll comply with applicable laws and regula tions; with the lease terms, Ons hore Oil

6 The Secretary’s authority to en act the portion of this regulat ion concerning inspections on privately-owned lands arises both from the gener al purposes provisions of FOGRMA, § 1701(b)(3 )-(5), as well as § 1711(a) an d (b). Section 1711(a) directs the Secretary, in part, to “establish a compreh ensive inspection . . . system,” and §1711(b) directs th e Secretary to conduct annual i nspections of certain lease sites, without limitation to sites contained on Federal o r Indian lands.23 and Gas Orders, NTL’s; and with o ther orders and instructions o f the authorized officer. These include , but are not limited to, con ducting all operations in a manner which en sures the proper handling, measurement, disposition, and site security of le asehold produc tion; which protects other natural re sources and environmental qualit y; which protects life and property; and which results in maximum ultima te economic recovery of oil and gas with minimum waste and with minimum adverse effect on ulti mate recovery of other mineral resources. (b) The operator shall permit properly identified authorized representatives to enter upon, travel across and inspect lease sites and records normally kept on the lease pertinent thereto without advance notice. Inspections normally will be conducted during those hours when responsible persons are expected to be present at the operation being inspected. Such permission shall incl ude access to secu red facilities on such lease sites for the purpos e of making any inspection or investigation for determining whethe r there is compliance with the mineral leasing laws, the regulations in this part, and any applicable orders, notices or directives. (c) For the purpose of making any in spection or investigation, the Secretary or his authorized represen tative shall have th e same right to enter upon or travel across any leas e site as the operator has acquired by purchase, condemnation or otherwise. 43 C.F.R. § 3162.1 (emphasis added). 7 The regulatory provisions thus pr ovide for an inspection framew ork that applies to federal, Indian, and certain privately-owned lands, but that, not surprisingly, provides the BLM w ith greater inspection authorit y over federal and Indian lands than privately-owne d lands. With respect to lease sites on federal and Indian land that are “produc ing or . . . expected to produce si gnificant quantities of oil or gas in a year or which ha [ve] a history of noncompliance with applicable

7 It was this regulation that Mar alex was cited for violating in the four INCs. Aplt. App. at 168.24 provisions of law or re gulations,” BLM repre sentatives must ins pect such lease sites “at least once annually.” 43 C.F. R. § 3161.3(a). As for lease sites on privatelyowned lands that are committed t o a unit or communitization agr eement that has been approved by the Department of the Interior, they are required t o “be inspected annually whenever” they are “pro ducing or . . . expected to pro duce significant quantities of oil or gas in any y ear or” if they “ha[ve] a hist ory of noncompliance with applicable provisions of law or regulations.” 8 43 C.F.R. § 3161.3(a). They can also be inspected by the BLM fo r purposes of assessing “site se curity, measurement, reporting of production and opera tions, and assessments or pena lties for noncompliance with such requireme nts.” 43 C.F.R. § 3161.2. Fu rther, the operating rights owner or operator of any such lease site on privately-ow ned land is required to “permit properly identified author ized representatives” of the BLM “to enter upon, travel across and inspect lease sites and records normally kept on the lease pertinent thereto without advance notice. ” 43 C.F.R. § 3162.1(b). Any s uch inspections, however, must normally “be conduc ted during those hours when re sponsible persons are expected to be present at the operation being inspected.” Id. In addition, “[s]uch permission” by the oper ating rights owner oroperator “shall in clude access to secured facilities on such lease sites for the purpose of makin g any inspection or investigation for determining wh ether there is compliance with the mineral leasing

8 In this case, the IBLA expressl y found that the wells at issue “are producing or expected to produce significa nt quantities of oil and gas,” thus rendering the wells subject to annual inspection unde r § 3163.3(a). Aplt. App. at 172.25 laws, the regulations . . . , and any applicable orders, notice s or directives.” Id. Lastly, BLM representatives are, “for the purpose of making any inspection or investigation,” afforded the sam e right of entry to and travel access across the lease site “as the operator has acqui red by purchase, condemnation orotherwise.” Id. § 3162.1(c). Thus, at least for purposes of th is case, the key difference be tween lease sites on federal/Indian lands and leas e sites on privately-owned landsubject to a communitization agreement is how B LM representatives may access them. For lease sites on federal/Indian lands, BLM representatives have the rig ht to enter those sites by themselves without first seek ing permission from the operati ng rights owner or operator. In contrast, for lease sites on privately-owned land s, BLM representatives may not independently enter the s ites, but instead must seek en try (but do not have to give advance notice) from the ope rating rights owner or operato r and the operating rights owner or operator, as not ed, is obligated to allow such entry. As for how often BLM representa tives may inspect the wells, the regulations contain no limitation. Indeed, the only reference to frequency of inspections is contained in § 3161.3(a), which , as noted, requires lease sites meeting certain requirements to be inspected a t least once annually. Section 3 161.3(a) does not, however, impose any upper limit on the number of inspections. In other words, as both the State Director and the IBLA concluded in their respect ive decisions, “[t]he [regulatory] wording ‘inspected a nnually’ is a minimum standardnot a maximum limitation.” Aplt. App. at 90; s ee id. at 176 n.10 (IBLA decis ion).26 In sum, the BLM had authority t o inspect the wells at issue. T he question remains, however, whether BLM h ad authority to require Maralex to provide BLM with “a key to access the loca tion or” allow BLM to install its own locks. Aplt. App. at 24). We agree with plaintiffs that the BLM lacks authority to requir e an operator or landowner to provide the BLM with a key to the landowner’s lock ed gates or to allow the BLM to place its own locks on the landowner’s locked gates. But we arrive at this conclusion in a different ma nner than suggested by plainti ffs. Although plaintiffs base many of their a rguments on the language of § 17 18(b), that statutory subsection, as discussed above, does not apply at all to lease sites on privately-owned lands. Instead, the parameters of inspections of lease sites o n privately-owned lands are outlined in two regulations: 30 C.F.R. §§ 3162.1 and 3163.3 . Neither of those regulations provide any authority for the BLM to require an ope rating rights owner or operator (or, for that matter, a private landowner) to (a) prov ide BLM with a key to a lease site on privately-owned la nd, or (b) to install a BLM-loc k on the gates to such lease site. Rather, as discusse d above, the BLM has the right to conduct unannounced inspections of such sites, but must rely on the ope rating rights owner or operator to afford them en try to the lease site. Defendants, for their part, cit e in their appellate brief to th e statutory and regulatory provisions a uthorizing the BLM to take “corrective a ction.” Aple. Br. at 39 (citing 30 U.S.C. §§ 1719(a)(2 )(A), (a)(2)(B) and 43 C.F.R. § 3163.1(a)(4)). Those statutory provisions, howev er, speak only in terms of mon etary “civil27 penalties” (the amount of which d epends upon how long the viola tion has gone on). 30 U.S.C. §§ 1719(a)(2), (b). T he regulatory provisions also m ention the possibility of lease cancellations and crimin al penalties. 43 C.F.R. §§ 31 63.1(a)(5), 3163.3. Notably, nothing in the statuto ry and regulatory provisions men tions the remedy imposed on the plaintiffs in th is case, i.e., requiring them to provide BLM with a key or to allow BLM to install its own locks. Although defendants concede this point, they nevertheless argue that “it is reasonable to conclude that when a landowner denies BLM entry, the very least that the agency can permissibl y do under the statute is order any reasonable remedy th at will yield the access requi red to carry out Congress’s charge.” Id. at 39- 40. We reject that argument. R equiring the provision of a key or lock access is, wit hout question, a drastic measure that would, at a minimum, require express congre ssional approval. Because no su ch approval appears in the relevant statutes or regulations, defendants’ ar guments must be rejected.
III We REVERSE and REMAND to the dis trict court with directions to enter judgment in favor of plaintiffs o n their claim that the BLM lac ks authority to require plaintiffs to provide the BLM w ith a key to acces s the wells atissue or to allow BLM to install its own locks.