NOT FOR PUBLICATION WITHOUT THE APPROVAL OF THE APPELLATE DIVISION

PER CURIAM.

The nature of this appeal cannot be understood without reference to a lawsuit commenced by the New Jersey Department of Environmental Protection (NJDEP) in 2005 that is still pending in the Law Division in Essex County.1 In this so-called Passaic River litigation, the NJDEP has sought relief pursuant to the common law and the New Jersey Spill Compensation and Control Act (the Spill Act), N.J.S.A. 58:10-23.11 to-23.24, regarding the alleged discharging of toxic chemicals from manufacturing facilities located on Lister Avenue in Newark. The NJDEP sued nine entities, including Maxus Energy Corporation and Tierra Solutions, Inc., alleging they or their predecessors had, for at least twenty years, polluted the Newark Bay complex2 with hazardous substances such as a particularly potent form of DDT.

Maxus and Tierra filed third-party complaints in the Passaic River litigation against approximately 300 public and private entities, seeking contribution pursuant to the Spill Act and the Joint Tortfeasors Contribution Act, N.J.S.A. 2A:53A-1 to -5, and alleging these third-party defendants—including the State of New Jersey, the New Jersey Department of Agriculture, the Port Authority of New York and New Jersey, seventy-three municipalities, and six sewerage treatment authorities-contributed to the contamination alleged in the NJDEP's complaint.

In September 2010, many of these third-party defendants moved in the Passaic River litigation for a dismissal of the Spill Act contribution claim asserted in the third-party complaint. The Law Division judge denied the motion on March 28, 2011, by relying on the Passaic River litigation's special master's recommendation, which was based on an interpretation of the words "sewage" and "sewage sludge" in an exception set forth in the Spill Act, N.J.S.A. 58:10-23.11b, as interpreted in N.J.A.C. 7:1E-1.6.

Although aggrieved by the order denying their motion to dismiss in the Passaic River litigation, the third-party defendant public entities did not seek leave to file an interlocutory appeal. Instead, some of them filed this appeal. Specifically, on February 16, 2012, appellants Linden Roselle Sewerage Authority, Rahway Valley Sewerage Authority, the City of Elizabeth, the City of Linden, the Port Authority, The Joint Meeting of Essex and Union Counties, Jersey City Municipal Utilities Authority and Passaic Valley Sewerage Commissioners, filed a notice of appeal, seeking a determination of "the validity of the N.J.A.C. 7:1E-1.6 definitions of `sewage' and `sewage sludge.'" The notice of appeal acknowledged that the regulation was adopted in 1977 and "last readopted" in 2007. An amended notice of appeal, which included additional appellants— Borough of Roselle, Borough of Roselle Park, City of Union City, Township of Maplewood, and City of Jersey City—was filed on March 9, 2012; this amended notice of appeal seeks review of the same regulatory definitions of "sewage" and "sewage sludge" originally adopted in 1977, but appellants noted further that this regulation was "readopted on September 6, 2011, ... filed on September 8, 2011..., and published on December 5, 2011 in the New Jersey Register in 43 N.J.R. 1203(a)."

In their merits brief, appellants argue that: (1) we have jurisdiction to invalidate a state agency regulation; (2) the NJDEP exceeded its delegated authority and violated the intent of the Spill Act in adopting N.J.A.C. 7:1E-1.6—because, in appellants' words, the regulation "impermissibly limits the definition of `sewage' and `sewage sludge' to domestic waste"; and (3) "the inconsistent interpretations of the sewage and sewage sludge regulation render the regulation void for vagueness." In response, the NJDEP argues that the regulation's "sewage" and "sewage sludge" definitions comport with the Spill Act and, further, that it has consistently interpreted these terms. Maxus and Tierra argue that the NJDEP has advocated in the Passaic River litigation for a new "sewage" definition, which conflicts with the existing regulation, but that the "sewage" definition in the regulation is neither void for vagueness nor unauthorized by the Spill Act. We also allowed the New Jersey State League of Municipalities to appear as amicus curiae. The League supports appellants' position, asserting that the Spill Act was intended to relieve the public from the burdens of pollution and ensure that the cost of cleanups and restoration are paid for by the responsible parties instead of the public; the League expresses concern that without our intervention, municipalities will be "dragged through litigation such as the [Passaic River] litigation."

Although no party has argued that this appeal is either untimely or otherwise not properly before us, we raised those and other similar concerns at oral argument. We now conclude that this appeal—thinly disguised as an appeal of an agency regulation—actually seeks appellate review of an interlocutory order entered in the Passaic River litigation. Because appellants were required to move for leave to appeal in the Passaic River litigation, rather than file an appeal as of right without seeking our leave, we dismiss this appeal.

The Spill Act, enacted thirty-six years ago, imposes strict liability on "any person who has discharged a hazardous substance, or is any way responsible for any hazardous substance." N.J.S.A. 58:10-23.11g(c)(1). In defining what is meant by a "hazardous substance," the Act expressly excludes "sewage and sewage sludge." N.J.S.A. 58:10-23.11b (declaring that "sewage and sewage sludge shall not be considered as hazardous substances for purposes of [the Spill Act]"). Because the Legislature did not provide a deeper understanding of what was meant by "sewage" and "sewage sludge," the NJDEP clarified it in 1978, defining "sewage" as "domestic sewage, including the contents and effluents of septic tanks, public sewer systems and public sewage treatment plants," and "sewage sludge" as "the dried or semi-liquid residue of a sewage treatment process." N.J.A.C. 7:1E-1.6. These definitions have gone unaltered the many times the regulation has been readopted in the decades that followed and as of this date. As a result, there is questionable merit in appellants' challenge that the regulation fails to comport with the Spill Act's intent. Because the Legislature has remained silent for so many years, it seems highly likely that the NJDEP correctly interpreted what the Spill Act meant by "sewage" and "sewage sludge" when it adopted, and continually readopted, the regulation in question. See Body-Rite Repair Co. v. Dir., Div. of Taxation, 89 N.J. 540, 545-46 (1982) (recognizing "a well-accepted principle that the practical administrative construction of a statute over a period of years without interference by the [L]egislature is evidence of its conformity with the legislative intent and should be given great weight by the [c]ourts"); see also Township of Dover v. Scuorzo, 392 N.J.Super. 466, 476 (App. Div. 2007); McKenzie v. Bd of Trustees of Pub. Employees' Retirement System, 389 N.J.Super. 456, 461 (App. Div. 2006).3

We gather it is not necessarily the regulation that troubles appellants. They argue the NJDEP has inconsistently interpreted its own regulation and cite to Hoffman-LaRoche, Inc. v. State of New Jersey, No. A-5922-91 (App. Div. Sept. 16, 1993) (slip op. at 13-14),4 which notes that the NJDEP therein argued that "[s]o long as a facility processes `primarily domestic wastewater and pollutants' as opposed to industrial waste, its sewage and sewage sludge meet the domestic classification." Appellants also refer us to the NJDEP's brief in Hoffman-LaRoche, in which the NJDEP argued that Hoffman-LaRoche's private treatment facility was not the equivalent of a publicly-owned treatment facility:

The NJDEP further argued in Hoffman-LaRoche that "[t]he Legislature most likely determined that the treatment residues of domestic treatment works, treating primarily domestic wastes, contained hazardous substances in such low concentration that they did not present a threat to human health and the environment and provided the sewage sludge exemption to codify the determination."

Appellants argue that, in this way, the NJDEP "reinterpreted the Spill Act exemption for `sewage' and `sewage sludge,' as defined by it in N.J.A.C. 7:1E-1.6, as being based on a percentage of material treated, i.e., whether the facility primarily treats domestic or industrial waste." They claim this reinterpretation or further parsing of the meaning of "domestic sludge" demonstrates the arbitrariness of the regulation and confusion about the Spill Act's reach that brought about the denial of their motion to dismiss the third-party Spill Act contribution claims in the Passaic River litigation.

We have no roving jurisdiction to examine whether—in some other civil actions concerning actual past or present controversies—the NJDEP has interpreted the regulation in a manner that fails to comport with the Spill Act. Even though we have jurisdiction to review an administrative regulation, R. 2:2-3(a)(2), and even though the authority to review administrative action is "exclusively in the Appellate Division," Pascucci v. Vagott, 71 N.J. 40, 52 (1976), we do not have jurisdiction—or an interest—in opening our doors for the sole purpose of determining whether the NJDEP has consistently interpreted and applied its regulation from case to case over the decades. Whether the NJDEP has taken a different approach to the regulation's meaning in this case when compared to another case—and, perhaps, should be estopped from doing so —is a matter to be considered in the case in which the alleged inconsistent position is taken. A litigant is not free to demand our intercession, by purporting to appeal a regulation, when in reality the litigant is not aggrieved by the regulation but by the manner in which it has been applied or interpreted in a given controversy.

In other words, what appellants actually dispute is not whether the regulation is inconsistent with the Spill Act, but whether the trial judge in the Passaic River litigation was persuaded by the NJDEP's alleged inconsistent interpretation of the regulation. To the extent the accusation of inconsistency may be true—and we neither offer nor intimate any view—is a matter to be decided in the context of the Passaic River litigation.

Consequently, we arrive where we began. What appellants have done here—in the guise of an appeal of an agency regulation—is attempt to engage this court in an untimely interlocutory appeal from an order denying their motion to dismiss the Spill Act contribution claim in the Passaic River litigation. Indeed, appellants hardly disguised this appeal, unabashedly revealing their intentions in their merits brief:

The procedures set forth in our Court Rules are not to be trifled with. Had appellants followed the appropriate procedure, they would have been required to seek in the Passaic River litigation, by motion, leave to appeal the interlocutory order denying their motion to dismiss.

Justice Brennan said for our Supreme Court many years ago that the judicial process chiefly consists of "a single and complete trial with a single and complete review." Trecartin v. Mahony-Troast Constr. Co., 21 N.J. 1, 6 (1956). "As a result, our judicial system recognizes that, with very few exceptions, only an order that finally adjudicates all issues as to all parties is a final order and that an interlocutory appeal is permitted only by leave of our appellate courts." Grow Co., Inc. v. Chokshi, 403 N.J.Super. 443, 457-58 (App. Div. 2008) (footnote omitted); see also Brundage v. Estate of Carambio, 195 N.J. 575, 599-600 (2008) (recognizing that the sole discretion to permit an interlocutory appeal is lodged with the appellate courts). Although our judicial system is biased in favor of a "single and complete review," our Rules allow for appellate review of interlocutory orders in exceptional circumstances or, as Justice Handler said for the Court in State v. Reldan, 100 N.J. 187, 205 (1985), the appellate court's power to grant leave to appeal an interlocutory order is "exercised only sparingly."

Here, appellants took it upon themselves to decide that we should hear this appeal on its merits rather than be bothered to try to convince us, by motion in the Passaic River litigation, that we should permit an interlocutory appeal rather than await entry of a final order. In Grow, we catalogued the many ways in which parties have attempted to skirt Rule 2:2-4 and the requirement that an interlocutory appeal is only permitted in our discretion, not the parties' or the trial court's discretion. 403 N.J. Super. at 458-59. We now add this case as yet another example. To reiterate what we said in Grow and others, "appellate resources are too scarce for this court to be so forgiving"—as we had been, even in the recent past, in cases such as Caggiano v. Fontoura, 354 N.J.Super. 111, 125 (App. Div. 2002)—"of fundamental departures from the finality rule." Grow, supra, 403 N.J. Super. at 459-60; see also House of Fire Christian Church v. Zoning Bd. of Adjust., Clifton, 426 N.J.Super. 157, 163-64 (App. Div. 2012); Vitanza v. James, 397 N.J.Super. 516, 518-19 (App. Div. 2008). As Judge Stern expressed in his opinion for the court in Parker v. City of Trenton, 382 N.J.Super. 454, 458 (App. Div. 2006), we now "struggle[] to decide over 7,000 appeals a year in a timely manner"; as a result, we "should not be presented with piecemeal litigation and should be reviewing interlocutory determinations only when they genuinely warrant pretrial review."

For these reasons, we cannot excuse appellants' attempt to sidestep our well-established appellate procedures through the filing of an appeal that ostensibly seeks review of an agency regulation as of right but, in actuality, is an appeal of an interlocutory order entered in a pending trial court action. It may be inconvenient for appellants to wait for entry of a final order in the Passaic River litigation, and, indeed, that delay may prove expensive.6 But, the vindication of our long-standing and well-established procedures regarding appellate review greatly preponderates over the parties' convenience. Because we cannot condone the means by which appellants have sought our intervention in the Passaic River litigation, we will not address the merits but will instead dismiss their appeal. Our disposition of this appeal is, of course, without prejudice to appellants' ultimate right to appellate review, in accordance with our established procedures, within the context of the Passaic River litigation.

Appeal dismissed.