PER CURIAM.

Defendants, the Department of Natural Resources, Holly Disposal, Inc., and William H. Leoni, Sr., previously appealed as of right to this Court from a June 28, 1989, permanent injunction barring Holly Disposal and Leoni from further construction of a solid waste landfill and precluding the DNR from issuing a construction permit for the landfill to Holly Disposal, Inc. We held that Mt. Holly Ski Area, Inc., did not have to exhaust its administrative remedies before bringing its action pursuant to the Environmental Protection Act (MEPA). We further found that the permit issued by the DNR that allowed construction of the landfill was invalid because the DNR failed to give the requisite notice concerning the third application for a construction permit. As a result, we remanded the case to the DNR to issue public notice of Holly Disposal's permit application. In addition, we held that because the permit was invalid, the trial court never should have reached the issue whether a permanent injunction should issue. Therefore, we vacated the permanent injunction. 189 Mich. App. 581; 473 N.W.2d 778 (1991).

Plaintiffs subsequently moved for rehearing, arguing that this Court erred in holding that the permanent injunction issued by the trial court in the MEPA action was necessarily invalid because the permit issued by the DNR for construction of the landfill was invalid. Plaintiffs argued that the MEPA action brought by Mt. Holly is independent from the application for a permit to construct and operate a landfill. We agreed and granted rehearing limited to reconsideration of this Court's vacation of the permanent injunction. On rehearing, we consider the merits of the permanent injunction granted by the trial court. We again vacate the permanent injunction.

This Court reviews de novo actions brought under the MEPA. Portage v Kalamazoo Co Road Comm, 136 Mich. App. 276, 279; 355 N.W.2d 913 (1984). However, the trial court's findings of fact will not be overturned unless they are clearly erroneous or unless the reviewing court is convinced it would have reached a different result had it occupied the bench at trial. Id. The grant or denial of an injunction is within the sound discretion of the trial court. Dafter Twp v Reid, 159 Mich. App. 149, 163; 406 N.W.2d 255 (1987). Injunctive relief is an extraordinary remedy that issues only when justice requires, there is no adequate remedy at law, and there is real and imminent danger of irreparable injury. Id., p 163, citing Wexford Co Prosecutor v Pranger, 83 Mich. App. 197, 205; 268 N.W.2d 344 (1978).

Defendants contend that a prima facie case was not established because the trial court failed to make the dual inquiry mandated. To determine whether a plaintiff has established a prima facie case under the MEPA, the trial court must consider whether a natural resource was involved and whether the effect of the activity on the environment rose to the level of impairment to justify the court's injunction. Portage, supra, p 280. There is no question that a natural resource was involved in this case. Whether the impact of the activity rises to the level to justify the court's injunction is a more difficult question to answer. The Michigan Supreme Court has recognized that virtually all human activities can be found to adversely affect natural resources in some way. Id., p 281, citing West Michigan Environmental Action Council v Natural Resources Comm, 405 Mich. 741, 760; 275 N.W.2d 538 (1979). However, a court is not empowered to enjoin any conduct that does not rise to the level of an environmental risk proscribed by the MEPA. Portage, supra, p 281. The applicable standard, "has or is likely to pollute," is a limitation as well as a power. Id., p 282, citing Oscoda Chapter of PBB Action Committee, Inc v Dep't of Natural Resources, 403 Mich. 215, 233; 268 N.W.2d 240 (1978).

In this case, it is arguable that Mt. Holly established a prima facie case of the likelihood of pollution. Mt. Holly's witnesses testified that the landfill would be located on porous sand and gravel. The witnesses testified that, eventually, leachate from the landfill would percolate through the landfill liner, through the sand and gravel, and down to the ground water and contaminate it because a recharge area was involved. Mt. Holly's experts testified that there was insufficient data to determine whether there was an aquiclude, or barrier to prevent movement of leachate to the ground water. Mt. Holly's witnesses testified that plaintiffs were located below the landfill and that the groundwater, filled with leachates from the landfill, would flow in plaintiffs' direction. Once a plaintiff establishes a prima facie likelihood of pollution, the burden of proceeding shifts to the defendant. MCL 691.1203; MSA 14.528(203); Ray v Mason Co Drain Comm'r, 393 Mich. 294, 311; 224 N.W.2d 883 (1975). However, the burden of proof stays with the plaintiff, and once the defendant rebuts the prima facie case of the likelihood of pollution, the burden of going forward with the evidence shifts back to the plaintiff. Id. The nature of the evidence necessary to rebut the plaintiff's showing varies. Id., pp 311-312.

Defendants' expert witness Kunkle testified that once the contaminants reached the water table they would move horizontally instead of vertically as Mt. Holly's expert had testified, because he believed that the area was a transitional or discharge zone, as opposed to a recharge area. Kunkle believed that any contaminants would be discharged into a marsh area rather than the ground water and plaintiffs' well water. Kunkle also claimed that the liner in the new landfill design was approximately ninety percent effective in preventing leakage. Kunkle testified that there is no scientific engineering design currently on the market that could completely guarantee that leachate would not contaminate the ground water.

We find that the trial court abused its discretion in granting the injunction. Dafter Twp, supra. At first glance, the case appears to be a battle between the experts. However, we find that there was insufficient evidence to justify the grant of a permanent injunction. Mt. Holly's main expert, Dr. Mozola, testified that there was insufficient data to determine if an aquiclude existed beneath the landfill site to prevent ground water contamination. He further testified that, unless specifically tested, it would be impossible to state, with any degree of certainty, the extent to which surrounding wells would draw contaminants from under the site because of the nature of the soils. The trial court noted that there had been no testimony regarding whether the levels of leachate reaching the domestic wells would be toxic. There is no indication regarding the impact the leaching would have under either design of the landfill. The trial court emphasized in its opinion that there was insufficient on-site testing and data upon which the parties' main experts could base their opinions and that their opinions were based on speculation. We also note that Mt. Holly's experts did not comment with regard to the new landfill design proposed by defendants and that there is no testimony regarding whether the allegedly reduced amount of leachate from the new design would result in a likelihood of pollution. Accordingly, we find that there was insufficient evidence upon which to grant the harsh remedy of a permanent injunction and that the trial court abused its discretion in doing so.

Injunction vacated.