Full Opinion

UNITED STATES DISTRICT COURT FOR THE DISTRICT OF COLUMBIA WASHINGTON METRORAIL SAFETY COMMISSION, Petitioner, v. Miscellaneous Action No. 24 - 144 (LLA) WASHINGTON METROPOLITAN AREA TRANSIT AUTHORITY, Respondent. MEMORANDUM OPINION Petitioner Washington Metrorail Safety Commission (the “WMSC” or “Commission”) seeks an order enforcing a subpoena it issued to Respondent Washington Metropolitan Transit Authority (“WMATA”). ECF No. 1. After the court referred the case for random assignment to a magistrate judge, ECF No. 8, Magistrate Judge Zia M. Faruqui issued an order in December 2025 granting the Commission’s petition to enforce the subpoena, ECF No. 9. The parties and the court agree that the Magistrate Judge’s order should be construed as a report and recommendation (“R&R”). WMATA has filed objections to the R&R, ECF No. 11, which are fully briefed, ECF Nos. 11, 15, 16. For the reasons discussed below, the court will overrule WMATA’s objections. I. BACKGROUND Neither party objects to the facts set forth in the background section of the Magistrate Judge’s order, so the court will adopt those findings. See Interstate Fire & Cas. Co. v. Wash. Hosp. Ctr. Corp., 917 F. Supp. 2d 87, 89 (D.D.C. 2013) (construing the magistrate judge’s memorandum opinion as an R&R and adopting the factual findings in the opinion’s background section). The court further summarizes the relevant facts below. A. The Commission’s Authority Over WMATA The District of Columbia, Maryland, and Virginia created WMATA to “plan, develop, finance, and . . . operate[]” a comprehensive mass transit system for the Washington, D.C. metropolitan area. Pub. L. No. 89-774, § 2, 80 Stat. 1324, 1325 (1967). Today, WMATA is comprised of Metrorail, a rail-operated public transportation system; Metrobus, a fixed-route bus service; MetroAccess, a door-to-door shared-ride “paratransit service[]”; and the Metro Transit Police Department. ECF No. 6, at 1-2. In the Moving Ahead for Progress in the 21st Century Act of 2012, Pub. L. No. 112-141, 126 Stat. 405 (the “Act”), Congress directed public transit systems like WMATA, which receive certain federal funds, to each establish a “comprehensive agency safety plan” containing safety targets and requirements, including “strategies to minimize the exposure of the public, personnel, and property to hazards and unsafe conditions, and consistent with guidelines of the Centers for Disease Control and Prevention or a State health authority, minimize exposure to infectious diseases,” 49 U.S.C. § 5329(d)(1)(D); see id. § 5329(d)(1)(A)-(H). The Act also requires funding-eligible states—or in WMATA’s case, the District, Maryland, and Virginia, collectively—to create a “State safety oversight program” that “assumes responsibility for overseeing rail fixed guideway public transportation safety,” 49 U.S.C. § 5329(e)(3)(A); “adopts 2 and enforces Federal and relevant State laws on rail fixed guideway public transportation safety,” id. § 5329(e)(3)(B); and “establishes a State safety oversight agency,” id. § 5329(e)(3)(C).1 The District, Maryland, and Virginia subsequently entered into the Washington Metrorail Safety Commission Interstate Compact, Pub. L. No. 115-54, 131 Stat. 1093 (2017) (the “Compact”), which designates the Commission as the “safety oversight agency” for WMATA’s Metrorail system,2 ECF No. 1 ¶¶ 10-11; ECF No. 6, at 4, 17; see State Safety Oversight Contacts, Fed. Transit Admin.3 The scope of the Commission’s oversight power is governed by Section 5329 and the Compact. The Commission has “exclusive safety oversight authority and responsibility over the WMATA Rail System pursuant to federal law.” § 3(a), 131 Stat. at 1095. Put differently, the Commission is vested with “investigative, inspection, and enforcement authority with respect to the safety of [WMATA’s] rail fixed guideway public transportation system[]”—that is, Metrorail. 49 U.S.C. § 5329(e)(4)(A)(v).4 Likewise, the Commission is 1 Because WMATA operates in the District, Maryland, and Virginia, all three must “[d]esignate a single entity” to “serve” as the state safety oversight agency. 49 C.F.R. § 674.15(b). 2 Before Congress passed the Act in 2012, the Tri-State Oversight Committee (“TOC”) had authority to “review” and “monitor” WMATA’s “safety program plan.” 49 U.S.C. § 5330(c) (2006); FTA Safety Oversight of the Washington Metropolitan Area Transit Authority (WMATA) Metrorail System, Fed. Transit Admin., https://perma.cc/8Z4J-7M7Q (hereinafter “FTA Safety Oversight”); Tri-State Oversight Committee, Md. Manual Online, https://perma.cc/83SB-3ML8. The TOC then served as WMATA’s oversight safety agency until October 2015, when the U.S. Secretary for Transportation directed the Federal Transit Administration to assume temporary oversight authority over WMATA. FTA Safety Oversight, supra; see 49 U.S.C. § 5329(e)(8) (allowing the Secretary of Transportation to temporarily administer a safety oversight program if the Secretary determines that the program fails to meet certain standards). The Federal Transit Administration later ceded control of Metrorail’s safety oversight to the Commission. ECF No. 6, at 4. 3 Available at https://perma.cc/9Z23-EXPB. 4 A “‘fixed guideway’” is a “public transportation facility” (A) “using and occupying a separate right-of-way for the exclusive use of public transportation”; (B) “using rail”; (C) “using a fixed catenary system”; (D) “for a passenger ferry system”; or (E) “for a bus rapid transit system.” 49 U.S.C. § 5302(8). 3 empowered to “review, approve, oversee, and enforce [WMATA’s] implementation” of the safety plan as it applies to Metrorail. Id. § 5329(e)(4)(A)(iv); see §§ 3(c), 30(b), 131 Stat. at 1095, 1098. As WMATA’s safety oversight agency, the Commission must also “audit[], at least once triennially, the compliance of [WMATA’s] rail fixed guideway transportation system[] . . . with the . . . agency safety plan.” 49 U.S.C. § 5329(e)(4)(A)(vi); see § 30(e), 131 Stat. at 1098. In performing its duties, the Commission may “[i]nvestigate hazards, incidents, and accidents on the WMATA Rail System,” § 3(d), 131 Stat. at 1095, and may “[c]onduct . . . inspections, investigations, examinations, and testing of WMATA personnel and contractors, property, equipment, facilities, rolling stock, and operations of the WMATA Rail System, including, without limitation, electronic information and databases through reasonable means,” id. § 31(a), 131 Stat. at 1098. The Compact empowers the Commission to issue subpoenas as part of its investigations, id., and this court has jurisdiction to hear actions brought by the Commission to enforce subpoenas issued pursuant to the Compact, id. § 48, 131 Stat. at 1101. B. The Commission’s Subpoena In October 2023, WMATA provided the Commission with a report indicating the presence of lead dust in several cabinets—located in at least one Metrorail station—that were used to store emergency medical equipment. ECF No. 1 ¶ 17; see ECF No. 1-3, at 20-21. In response, the Commission added a “specific focus on workplace safety” to its upcoming triennial audit of WMATA’s “fitness for duty programs.” ECF No. 1 ¶ 19. The parties corresponded over several months as the Commission asked lead-related follow-up questions and WMATA generally supplied the requested information. See id.; ECF No. 1-3, at 4-20. In February 2024, the Commission provided WMATA with written notice of a “safety audit of WMATA’s fitness for duty and occupational health programs.” ECF No. 1 ¶ 20 (quoting 4 ECF No. 1-4, at 1). The notice indicated that the Commission was conducting its safety audit pursuant to 49 C.F.R. part 674—the federal regulations for state safety oversight pursuant to Section 5329. ECF No. 1-4, at 1; see, e.g., 49 C.F.R. § 674.31 (requiring state safety oversight agencies to conduct triennial audits as required by Section 5329(e)(4)(A)(vi)). The fitness for duty portion of the audit addressed the “mitigation of hazards related to an individual’s physical and mental condition,” whereas the occupational health inquiry focused on the “mitigation of hazards related to workplace conditions.” ECF No. 1-4, at 1. The Commission stated that it would “conduct field observations in or around the WMATA Rail System,” interview relevant individuals, and review records. Id. The written notice expressly exempted “alternate exit routes, emergency action plans, and fire prevention plans” from the scope of the occupational health audit “to prevent confusion regarding regulations set by the federal Occupational Safety and Health Administration” (“OSHA”). Id. at 2 n.2. Along with notice of the audit, the Commission sent WMATA a request for twenty-eight categories of documents and information concerning “employee fitness, occupational health, training, various bodily and environmental safety programs, drug and alcohol testing, and exposure to hazardous substances,” ECF No. 1 ¶ 22; see ECF No. 1-5, and requested a response by March 11, 2024, ECF No. 1 ¶ 23. Days before the deadline to respond, WMATA informed the Commission that the occupational health portion of the audit exceeded the Commission’s authority, duplicated existing oversight by other state and federal agencies, and risked subjecting WMATA to inconsistent regulatory requirements. ECF No. 1-6, at 2-3. WMATA also maintained that compliance would be overly burdensome. Id. at 2. In April 2024, the Commission served WMATA with an administrative subpoena demanding responses to the twenty-eight requests for documents and information. See ECF No. 1 5 ¶ 29 (“The Subpoena does not expand the scope of the Initial Request.”); see also ECF No. 1-9.5 WMATA sent the Commission general and request-specific objections to the subpoena, id., and the Commission responded to WMATA’s concerns, ECF No. 1-10. By June 2024, WMATA had produced “only a few documents” in response to the subpoena and had “left many requests unaddressed.” ECF No. 1 ¶ 32. The parties conferred for several months to resolve the disagreements; as a result, WMATA has now provided “acceptable initial responses to fitness for duty requests and most drug and alcohol program-related requests,”6 but it “refuse[s] to produce information in response to the requests regarding workplace health.” Id. ¶ 34. Still outstanding are requests 2(b), 3, 22, and 24 through 28, and the parts of requests 11, 12, and 23 that concern occupational health. Id. Those requests concern the following information: ▪ Request 2(b): “All policies and procedures (Metrorail-wide, departmental, organizational unit level and all documents from policy instructions down to work instructions) related to . . . [o]ccupational health programs.” ▪ Request 3: “[C]urrent program documents including any governing documents and procedures (Metrorail-wide, departmental, organizational unit level and all documents from policy instructions down to work instructions)” for various programs.7 5 Inexplicably, the parties have not provided the court with a copy of the subpoena at issue, so the court has relied on WMATA’s objections to the subpoena and the Commission’s responses in order to understand the subpoena’s scope. See ECF No. 1-9 (WMATA’s objections); ECF No. 1-10 (the Commission’s responses). 6 The “acceptable” responses covered requests 1, 2(a), 4 through 10, 14 (although not in the Commission’s preferred format), 15 through 21, and parts of requests 11, 12, and 23. ECF No. 1 ¶ 34. 7 This request included documents covering (a) walking-working surfaces like “[l]adder [s]afety, stairways, platforms, manlifts, scaffolding, [and] protection from falling objects”; (b) environmental control, including “ventilation, noise exposure . . . , and nonionizing radiation”; (c) hazardous materials like “compressed gases, petroleum gases, hazardous chemicals, and hazardous waste”; (d) personal protective equipment; (e) general environmental controls, including “safety color codes for marking physical hazards, specifications for accident prevention (continued on next page) 6 ▪ Request 11: “All training requirements related to . . . occupational health programs.” ▪ Request 12: “All training curricula, trainings, class schedules, and exams related to . . . occupational health programs.” ▪ Request 22: “All existing data reports/trend data related to dosimetry testing, indoor air quality, toxic and hazardous substances, [j]ob hazard analyses, PPE usage, training overdue for health and safety programs, [and] employee safety concerns for the period January 1, 2021 through December 31, 2023.” ▪ Request 23: “[A]ll . . . occupational health reporting requirements required by the federal government, the District of Columbia, Maryland, and Virginia.” ▪ Request 24: “All occupational health inspection reports that relate to the WMATA Rail System from the federal Occupational Safety and Health Administration, [and] the occupational health agencies from the District of Columbia, Maryland, and Virginia for the period January 1, 2022 through January 31, 2024.” ▪ Request 25: “All medical monitoring results for welders and other employees who engage in hot work from January 1, 2021 through December 31, 2023.” ▪ Request 26: “All noise and dosimetry test schedules and results from January 1, 2021 through December 31, 2023”; “[a]ll documents confirming that audible or hearing tests are undertaken for personnel working in areas above WMATA’s time-weighted average for noise levels”; and “[a]ll medical monitoring results for employees exposed to an 8-hour time-weighted average (TWA) noise level of 85 decibels (dBs) or above or per the thresholds in WMATA’s hearing conservation program.” ▪ Request 27: “All exposure reports for air and surface monitoring regarding specific substances including without limitation, silica, asbestos, hexavalent chromium, lead, or any other toxic or hazardous substances from January 1, 2021 through December 31, 2023.” and tags, permit-required confined spaces, and control of hazardous energy”; (f) medical and first aid; (g) materials handling and storage like “powered industrial trucks, overhead and gantry cranes, crawler locomotive and truck cranes, and slings”; (h) machinery and machine guarding for “woodworking or metal machinery, abrasive wheel machinery, forging machines, and mechanical power-transmission apparatuses” like “mechanical and hydraulic power presses”; (i) hard and portable powered tools and hand-held equipment guarding; (j) any type of welding; (k) electrical safety, including “wiring design protection, specific purpose equipment and installations, hazardous (classified) locations, third rail safety on the right-of-way, and safety-related work practices”; and (l) various toxic and hazardous substances, including asbestos, carcinogens, benzene, and bloodborne pathogens, among others. ECF No. 1-5 ¶ 3. 7 ▪ Request 28: “All exposure reports from bloodborne pathogens and associated medical monitoring results from January 1, 2021 through December 31, 2023.” ECF No. 1-5 ¶¶ 2(b), 3, 11-12, 22-28 (footnote omitted). II. PROCEDURAL HISTORY In October 2024, the Commission filed a petition seeking an order enforcing the subpoena. ECF No. 1. After briefing, ECF Nos. 1, 6, 7, the court referred the matter to a magistrate judge in December 2024 for full case management, ECF No. 8. In December 2025, the Magistrate Judge issued an order granting the petition. ECF No. 9. He concluded that the Compact authorized the Commission to issue the subpoena because a subpoena targeting WMATA’s occupational safety and health (“OSH”) practices falls within the Commission’s general authority to investigate safety-related risks and hazards on WMATA’s Metrorail system. Id. at 3-5. In so concluding, he rejected WMATA’s argument that only state and federal occupational safety and health agencies may regulate OSH. Id. at 5-6. Additionally, the Magistrate Judge concluded that WMATA’s compliance with the subpoena would not pose an undue burden. Id. at 7-9. As required by 28 U.S.C. § 636(b) and Federal Rule of Civil Procedure 72(b)(2), WMATA filed timely objections to the Magistrate Judge’s order, ECF No. 11, which are fully briefed, ECF Nos. 11, 15, 16. Based on the parties’ agreement, ECF Nos. 12, 14, the court has stayed WMATA’s obligation to respond to the subpoena until the issuance of this opinion, Jan. 8, 2026 Minute Order. III. LEGAL STANDARD “Administrative agencies wield broad power to gather information through the issuance of subpoenas.” Consumer Fin. Prot. Bureau v. Accrediting Council for Indep. Colls. & Schs., 854 F.3d 683, 688 (D.C. Cir. 2017) (quoting Resol. Trust Corp. v. Thornton, 41 F.3d 1539, 1544 8 (D.C. Cir. 1994)); see Fed. Trade Comm’n v. Ken Roberts Co., 276 F.3d 583, 586 (D.C. Cir. 2001) (noting the “long-standing doctrine that administrative agencies must be given wide latitude in asserting their power to investigate by subpoena”). The federal courts of appeals have therefore “consistently deferred to agency determinations of their own investigative authority” and “generally refused to entertain challenges to agency authority in proceedings to enforce compulsory process.” Ken Roberts Co., 276 F.3d at 586 (collecting cases). But the “[s]ubpoena enforcement power is not limitless.” Id. The court plays a “limited” role, id. at 587, to ensure that (1) “the inquiry is within the authority of the agency” and does not “exceed[] an express statutory limitation on the agency’s investigative powers”; (2) “the demand is not too indefinite”; and (3) “the information sought is reasonably relevant,” id. at 586 (internal quotation marks omitted). On the first question, the D.C. Circuit “[has] held that enforcement of an agency’s investigative subpoena will be denied only when there is a ‘patent lack of jurisdiction’ in an agency to regulate or to investigate.” Id. at 587 (quoting Civil Aeronautics Board v. Deutsche Lufthansa Aktiengesellschaft, 591 F.2d 951, 952 (D.C. Cir. 1979), and collecting cases); see Fed. Trade Comm’n v. CVS Health Corp., No. 25-MC-3, 2025 WL 3546175, at *2 (D.D.C. Feb. 24, 2025). In addition to assessing an agency’s authority and the terms of a subpoena, the court must consider whether an entity’s compliance with the subpoena would be “unduly burdensome.” Accrediting Council for Indep. Colls. & Schs., 854 F.3d at 689; United States v. Legal Servs. for N.Y.C., 249 F.3d 1077, 1084 (D.C. Cir. 2001) (explaining that while “concerns over burden are related to relevance,” the two involve distinct inquiries). For unduly burdensome requests, the court may “impose reasonable conditions and restrictions with respect to the production of the subpoenaed material.” Fed. Trade Comm’n v. Texaco, Inc., 555 F.2d 882, 881 (D.C. Cir. 1977). The subpoenaed party bears the burden of establishing that compliance is unreasonable. Id. at 882. 9 Some burden is “expected” and will be “necessary” to further the “agency’s legitimate inquiry and the public interest”; accordingly, the burden of proving unreasonableness is “not easily met” where the “inquiry is pursuant to a lawful purpose and the requested documents are relevant to that purpose.” Id. Courts in this Circuit have therefore rejected undue-burden arguments even when “compliance would be extremely costly, labor intensive, and in certain cases, impossible.” CVS Health Corp., 2025 WL 3546175, at *3 (quoting Fed. Trade Comm’n v. Invention Submission Corp., No. 89-MC-272, 1991 WL 47104, at *3 (D.D.C. Feb. 14, 1991)); see Texaco, 555 F.2d at 882 (explaining that courts “have refused to modify investigative subpoenas unless compliance threatens to unduly disrupt or seriously hinder normal operations of a business”). IV. DISCUSSION A. Standard of Review The parties first address the legal effect of the Magistrate Judge’s order and what standard of review this court should apply. Unless the parties have consented to proceed before a magistrate judge for all purposes, a district judge’s review of a magistrate judge’s decision takes one of two forms. If the issue is “dispositive of a claim,” the magistrate judge must make “proposed findings of fact” and “enter” an R&R. Fed. R. Civ. P. 72(b)(1); see 28 U.S.C. § 636(b)(1)(B)-(C); see also Local Civ. R. 72.3. The district court must then “determine de novo any part of the magistrate judge’s disposition” subject to an objection and “accept, reject, or modify the recommended disposition; receive further evidence; or return the matter to the magistrate judge with instructions.” Fed. R. Civ. P. 72(b)(3); see 28 U.S.C. § 636(b)(1)(B)-(C); see also Local Civ. R. 72.3(c). In contrast, for non-dispositive matters, the magistrate judge “issue[s] a written order stating the decision,” which the district court, upon objection by a party, may modify or set aside 10 only to the extent that it is “clearly erroneous” or “contrary to law.” Fed. R. Civ. P. 72(a); see 28 U.S.C. § 636(b)(1)(A); see also Local Civ. R. 72.2. The statute governing the jurisdiction and authority of magistrate judges sets forth several dispositive matters, including motions to dismiss for failure to state a claim, motions for judgment on the pleadings, and motions for summary judgment, among others. 28 U.S.C. § 636(b)(1)(A). A petition to enforce an administrative subpoena is not on that list. See id. While the list “appears to be exhaustive,” the Supreme Court “has identified some judicial functions as dispositive notwithstanding” the statute’s failure to expressly include them. Flam v. Flam, 788 F.3d 1043, 1046 (9th Cir. 2015); see, e.g., Gomez v. United States, 490 U.S. 858, 873-74 (1989) (holding that although Congress “did not identify the selection of a jury as either a ‘dispositive’ matter . . . or a ‘nondispositive’ pretrial matter . . . jury selection is more akin to those precisely defined, ‘dispositive’ matters [that require] de novo review”). Courts employ a “functional approach that looks to the effect of the motion” to “determine whether it is properly characterized as dispositive or non-dispositive of a [party’s] claim.” ML-CFC 2007-6 P.R. Props., LLC v. BPP Retail Props., LLC, 951 F.3d 41, 47 (1st Cir. 2020) (quoting Flam, 788 F.3d at 1046); see Vogel v. U.S. Off. Prods. Co., 258 F.3d 509, 515 (6th Cir. 2001) (“The list of dispositive motions contained in [Section] 636(b)(1)(A) is nonexhaustive, and unlisted motions that are functionally equivalent to those listed in [Section] 636(b)(1)(A) are also dispositive.”). For example, the Sixth Circuit has held that motions for default judgment, for sanctions under Federal Rules of Civil Procedure 11 and 37, and to proceed in forma pauperis are all dispositive because they are functionally equivalent to the motions listed in Section 636(b)(1)(A). Vogel, 258 F.3d at 515 (collecting cases). Here, neither party consented to referral to a magistrate judge for all purposes, so the Magistrate Judge lacked authority to issue a binding ruling if the matter was dispositive. See ECF 11 No. 8; CPC Patent Techs. PTY Ltd. v. Apple, Inc., 34 F.4th 801, 807 (9th Cir. 2022) (explaining that “a magistrate judge may not issue binding rulings on case-dispositive matters without the parties’ consent”). The issue before the Magistrate Judge here—the Commission’s petition to enforce the administrative subpoena—was the sole legal claim in the case. See ECF No. 8, at 1; ECF No. 9, at 1 (noting that the court was considering the Commission’s petition). Yet the Magistrate Judge granted the petition in full and directed WMATA to produce documents within thirty days. ECF No. 9, at 1, 10. In doing so, he viewed the petition to enforce as a “non-dispositive matter” like a motion to compel discovery and subject to this court’s review for clear error or conclusions that are contrary to law. Id. at 10 n.4 (quoting United States v. All Assets Held at Bank Julius, No. 04-CV-798, 2016 WL 11609892, at *2 (D.D.C. Jan. 12, 2026)). The court agrees with the parties that the Magistrate Judge’s order was dispositive and, pursuant to Section 636(b), Federal Rule of Civil Procedure 72, and Local Civil Rules 72.2 and 72.3, should be construed as an R&R. See ECF No. 11, at 10; ECF No. 15, at 5. Whereas a motion to compel discovery involves a discrete dispute that is “part of a larger case,” the Commission’s petition—which does not arise out of a preexisting enforcement proceeding before the court—is itself the entire pending action. See Nat’l Lab. Rels. Bd. v. Frazier, 966 F.2d 812, 817 (3d Cir. 1992) (reversing a district court’s determination that a magistrate judge’s order enforcing a subpoena was “nondispositive”); CPC Patent Techs. PTY Ltd., 34 F.4th at 808 (concluding that a “freestanding” request to enforce a subpoena under 28 U.S.C. § 1782, “filed on its own and not in conjunction with another federal lawsuit,” was dispositive because deciding it resolved the “ultimate” request for relief even if discovery motions are typically non-dispositive (internal quotation marks omitted)); see also Equal Emp. Opp. Comm’n v. City of Long Branch, 12 866 F.3d 93, 100-01 (3d Cir. 2017) (reversing a district court that failed to apply Frazier by treating a magistrate judge’s order enforcing an agency’s administrative subpoena as non-dispositive). The Magistrate Judge considered the parties’ briefing, evaluated WMATA’s declaration, determined that the Commission was entitled to enforce its subpoena, and ordered WMATA to comply. Because the validity of the administrative subpoena presents the sole claim for review in this case, the Magistrate Judge’s order was dispositive, much like one granting a motion for judgment on the pleadings or for summary judgment. See Fed. R. Civ. P. 72(b)(1)(A); Local Civ. R. 72.3(a)(3); cf. Frazier, 966 F.2d at 817 (concluding that a magistrate judge’s denial of a petition to enforce a subpoena had the same effect as granting a motion to dismiss). Accordingly, the Magistrate Judge’s decision functions as an R&R to this court, which triggers this court’s de novo review of WMATA’s objections. See Interstate Fire & Cas. Co., 917 F. Supp. 2d at 89, 94 (construing the magistrate judge’s order as an R&R and “accordingly, review[ing] the portions to which [the party] ha[d] objected under a de novo standard”); id. at 89 (concluding that the party objecting to the magistrate judge’s decision would “not [be] prejudice[d]” by the court’s treatment of the decision as an R&R because it “had the opportunity to lodge its objections . . . and to brief the relevant issues fully”); see also Fed. Trade Comm’n v. Bisaro, 757 F. Supp. 2d 1, 2 (D.D.C. 2010) (conducting de novo review of a magistrate judge’s R&R recommending that an agency’s petition to enforce a subpoena be granted); Commodity Futures Trading Comm’n v. First State Depository Co., No. 21-MC-48, 2021 WL 7448016, at *1 n.1 (D.D.C. June 23, 2021) (concluding that a magistrate judge’s R&R “was appropriate” because a petition to enforce a subpoena “is a case-dispositive matter”). 13 B. Merits WMATA lodges four objections to the Magistrate Judge’s order. The first three concern the Magistrate Judge’s conclusion that the administrative subpoena seeks information “within the WMSC’s authority.” ECF No. 11, at 9. In WMATA’s view, the Magistrate Judge incorrectly concluded that the subpoena is consistent with the Commission’s (1) “authority over ‘safety’”; (2) responsibility to “‘audit’ WMATA’s compliance with its Safety Plan”; and (3) power to “investigate ‘hazards.’” Id. at 9-10 (quoting ECF No. 9, at 4-5); see id. at 12-24; see also ECF No. 9, at 4-6. Finally, WMATA contends that the Magistrate Judge erred in determining that its compliance with the subpoena does not pose an undue burden. ECF No. 11, at 10; see id. at 24-27; see also ECF No. 9, at 7-9. None of WMATA’s objections has merit. On de novo review, the court agrees with the Magistrate Judge’s “disposition” of the petition: the Commission has authority to issue its subpoena and WMATA has failed to establish that compliance poses an undue burden. Fed. R. Civ. P. 72(b)(3). Accordingly, the court will overrule WMATA’s objections. Before turning to WMATA’s specific objections, the court notes that WMATA appears to misunderstand the nature of this dispute. WMATA suggests that this case, including the Magistrate Judge’s R&R, implicates the question whether the Commission may conduct “general regulation of workplace health and safety” outside of Metrorail. ECF No. 6, at 17; see ECF No. 11, at 15 (arguing that the Commission was not “created . . . to regulate safety generally in whatever form it is implicated” and asserting that the Compact does not “grant[] [the Commission] plenary authority over all aspects of WMATA operations”). WMATA’s concerns are somewhat understandable, especially in light of Request 11, seeking “[a]ll training requirements related to . . . occupational health programs,” ECF No. 1-5 ¶ 11; Request 12, seeking “[a[ll training curricula, trainings, class schedules, and exams related to . . . occupational health programs,” id. 14 ¶ 12; and Request 23, seeking “[a]ll . . . occupational health reporting requirements,” id. ¶ 23— none of which appear to be facially limited to Metrorail. But WMATA’s framing is incorrect. The Commission has repeatedly stated that—even as to those facially broader requests—its oversight authority extends only to Metrorail, and not to Metrobus, MetroAccess, or the Metro Transit Police Department. ECF No. 15, at 8 n.1 (“[T]he WMSC’s authority . . . encompass[es] Metrorail exclusively, as opposed to the other modes of transportation that WMATA provides.”). For that reason, the Commission represents that its subpoena only seeks documents related to Metrorail. Id. at 17 (noting that all the subpoenaed documents “relate . . . to Metrorail personnel”); see, e.g., ECF No. 1-5 ¶ 24 (Request 24, seeking all “occupational health inspection reports that relate to the WMATA Rail System” (emphasis added) (footnote omitted)). That view is consistent with the Compact, which limits the Commission’s “safety regulatory and enforcement authority” to “the WMATA Rail System.” § 2, 131 Stat. at 1095. The court therefore understands the contested requests in the subpoena—and the Magistrate Judge’s order directing WMATA’s compliance with those aspects of the subpoena—to relate only to Metrorail. With that framing, the court turns to WMATA’s specific objections. 1. The Commission’s oversight concerning the “safety” of the Metrorail system WMATA asserts that the Magistrate Judge erroneously concluded that the Commission has authority to issue the contested portions of the subpoena in an exercise of its general oversight of safety-related issues on the Metrorail system. ECF No. 11, at 9-10, 12-20; see ECF No. 9, at 3-4. The court is unpersuaded because the Magistrate Judge correctly determined that the Commission holds broad power to investigate issues implicating Metrorail safety. The Commission’s authority stems from multiple sources. First, federal law gives the Commission “investigative, inspection, and enforcement authority with respect to the safety of [the Metrorail 15 system].” 49 U.S.C. § 5329(e)(4)(A)(v). In turn, the Compact vests the Commission with the power to “enforce relevant federal and State laws and regulations relating to safety of the WMATA Rail System.” § 30(d), 131 Stat. at 1098. These two provisions plainly authorize the Commission to investigate and enforce safety-related issues—and to do so, the Commission may issue subpoenas. Id. § 31(a), 131 Stat. at 1098. Whether this oversight power includes the OSH-related topics in the subpoena thus turns on the meaning of the term “safety.” The court begins with the text and statutory context of both Section 5329 and the Compact. See Crowley Gov’t Servs., Inc. v. Gen. Servs. Admin., 143 F.4th 518, 532 (D.C. Cir. 2025). Neither Section 5329 nor the Compact defines the term “safety,” see 49 U.S.C. §§ 5302, 5329; 131 Stat. at 1093-1104, so the court interprets the term according to its “ordinary, contemporary, common meaning,” Food Mktg. Inst. v. Argus Leader Media, 588 U.S. 427, 433-34 (2019) (quoting Perrin v. United States, 444 U.S. 37, 42 (1979) (looking to dictionaries at the time a statute was enacted). The court also considers “the context in which [the term ‘safety’] is used.” Solar Energy Indus. Ass’n v. Fed. Energy Regul. Comm’n, 154 F.4th 863, 868 (D.C. Cir. 2025) (quoting Reno v. Koray, 515 U.S. 50, 56 (1995)). At the time Congress passed the Act, the ordinary, common meaning of “safety” referred to the “condition of being safe from undergoing or causing hurt, injury, or loss.” Safety, Merriam Webster’s Collegiate Dictionary 1095 (11th ed. 2011); see Safety, American Heritage Dictionary 728 (5th ed. 2012) (“[f]reedom from danger, risk, or injury”); Safety, Webster’s New World College Dictionary 1279 (5th ed. 2014) (“freedom from danger, injury, or damage”). The same contemporary meaning existed several years later when the District, Maryland, and Virginia formed the Commission. See Safety, Merriam-Webster Dictionary 637 (2016) (“freedom from danger”). As these definitions make plain, the meaning of the term “safety” is broad—covering any risk of pain, injury, loss, danger, or damage—and plainly encompasses 16 OSH as WMATA uses the term. See ECF No. 1-2, at 37 (explaining that WMATA’s Office of Occupational Safety and Health’s “priority is the health, safety, and well-being of Metro’s workforce by minimizing injuries and illnesses from exposure to occupational hazards”). 8 And “safety” likewise covers the items in the Commission’s subpoena because they relate to issues that may cause or mitigate risk, danger, or injury. See, e.g., ECF No. 1-5 ¶ 3 (Request 3, seeking program documents that cover things like scaffolding and cranes, falling objects, ventilation, hazardous chemicals and toxic substances, physical hazards, first aid, machinery and tools, and electrical equipment); id. ¶¶ 22, 27 (Requests 22 and 27, seeking reports on air quality, toxic and hazardous substances, and employee safety concerns); id. ¶ 25 (Request 25, seeking “medical monitoring results for welders and other employees who engage in hot work”). Accordingly, the Commission’s “investigative, inspection, and enforcement authority with respect to the safety of [the Metrorail system],” 49 U.S.C. § 5329(e)(4)(A)(v), and power to “enforce relevant federal and State laws and regulations relating to safety of the WMATA Rail System,” § 30(d), 131 Stat. at 1098, allow the Commission to issue and enforce its subpoena.9 WMATA reads the Compact to limit “safety” to issues arising out of the physical operation of rail cars on Metrorail tracks—or, in other words, those matters connected to the “rail fixed 8 The citations to ECF No. 1-2 refer to the CM/ECF-generated page numbers at the top of each page rather than any internal pagination. 9 WMATA also points out that Commission members must have “backgrounds in transit safety, transportation, [or] relevant engineering disciplines,” expertise that WMATA asserts does not overlap with OSH issues. ECF No. 11, at 5 (alteration in original) (quoting § 9, 131 Stat. at 1096)). In WMATA’s view, that requirement proves that the Commission lacks oversight over anything related to OSH. Id. at 15-16. But even if the Compact’s employment qualifications could upend its plain text giving the Commission authority over Metrorail safety—and it cannot—WMATA’s argument is unpersuasive because it is circular: the Commission members’ “rail-focused expertise” bears no connection to “OSH issues” only if “transit safety” does not encompass some OSH principles, which is the very conclusion WMATA seeks to prove. Id. 17 guideway public transportation” system. ECF No. 11, at 15. Not so. The Compact contemplates that the Commission will conduct oversight of anything relating to the safety of the “the rail fixed guideway public transportation system and all other real and personal property owned, leased, operated, or otherwise used by WMATA rail services and shall include WMATA rail projects under design or construction by owners other than WMATA.” § 1(m), 131 Stat. at 1094 (emphasis added) (defining “WMATA Rail System” or “Metrorail”). While WMATA only focuses on the first portion of that definition, the second half sweeps much broader and gives the Commission authority over anything that poses a risk of pain, injury, loss, danger, or damage on or to Metrorail-related property or projects. And the Commission, when exercising its oversight power, may investigate “WMATA personnel and contractors, property, equipment, facilities, rolling stock, and operations of the WMATA Rail System.” Id. § 31(a), 131 Stat. at 1098. Together, the various overlapping provisions in the Compact support an interpretation of “safety” oversight that authorizes the portions of the subpoena that WMATA finds objectionable. For example, WMATA contends that “lead-exposure issues” on the Metrorail have no bearing on “fixed-rail safety.” ECF No. 11, at 5; see ECF No. 1-5 ¶ 27. But lead exposure at a Metrorail station undeniably poses a risk of danger and injury to those on the “rail fixed guideway public transportation system.” § 1(m), 131 Stat. at 1094. Likewise, documents concerning ladder safety, scaffolding, and protection from falling objects, ECF No. 1-5 ¶ 3(a), plainly address potential injury or damage to WMATA employees and contractors on “WMATA rail projects under design or constru