The instant appeal arises from an Order by the lower court, sitting en banc, which denied the Appellants’ exceptions to a Decree Nisi. The lower court adopted the Chancellor’s Decree Nisi as its Final Decree. This action was initiated by the Appellee landowners to seek equitable relief as the result of the contamination of the Appellees’ ground water supplies.
The factual record, which is substantial in this case, shows the following:1 The Appellants, Elmer J. Custer, Jr., Russell A. Custer and Irvin E. Custer had for many years operated, as a partnership, a service station and garage in the Village of Oaks, in Montgomery County. The Custers purchased their petroleum products from the Appellant Mobil Oil Corporation, which was also the owner and lessor of the underground tanks in which the Custers stored the gasoline sold in their station.
*246On Monday, July 16, 1979, Elmer K. Custer, Jr. opened the service station, which had been closed the prior two days. He pumped ten to eleven gallons of gasoline into the vehicle of the first customer of the day, when for no apparent reason the flow of gasoline from the pump ceased. He immediately checked the gasoline storage tank which serviced his pumps. This tank, which had a 4,000 gallon storage capacity, was “manifolded” to another 2,000 gallon underground tank. The system operated so that the smaller tank fed into the larger one. When he checked the tank with a “dip-stick”, he concluded that it was empty.
Elmer K. Custer, Jr. promptly called the police because he suspected possible foul play. The prior weekend had been announced as a period for a state-wide shutdown of gas stations by an independent gasoline dealers’ association. On Friday, July 13, 1979, when the shutdown was scheduled to begin, Elmer Custer received a telephone call from an anonymous caller who asked if Custers’ station would be open that day. After Elmer answered in the affirmative, the caller stated that he would not recommend that it be opened. During the hearings before the Chancellor, a witness unrelated to the parties testified that late in the evening on Friday, July 13, 1979, he observed a man standing next to a silver colored petroleum tanker truck parked in the driveway of the Custers’ station. He further testified that he did not observe any logo on the side of the tanker, but did see a hose running from the center of the tanker into the ground at the area of the intake for the underground tanks. Russell Custer testified that he could not recall any time during his thirty years in business when he had received a shipment of gasoline from a tanker truck with no logo, nor could he recall ever receiving a delivery in the evening.
Records maintained by the Custers indicated that as of July 13, 1979, their tanks should have contained 3,338 gallons of fuel, plus or minus ten to twenty gallons. They promptly notified Mobil of the loss of gasoline and on July 17, 1979 two Mobil employees visited the station. These *247representatives also confirmed the absence of fuel in the tanks by dip-stick measuring them. They also discovered that the Custers did not maintain appropriate records in regard to the fuel, and were not aware that there was a state law (See 35 P.S. § 1181), which required a daily reading of the tanks by a dip-stick measurement. It had been the Custers’ practice to make such a measurement only once a week. The Custers instead calculated the amount of fuel they had in storage on a daily basis by taking a reading from gauges on each pump which indicated the amount of gasoline dispensed through that pump each day. From these readings, figures were derived which were tallied on a daily inventory sheet, although it was conceded by Elmer Custer that the dials on the gas pumps only registered how much fuel came out of the tanks and did not accurately indicate how much fuel remained in the tanks, between weekly dip-stick readings.
In an effort to determine the manner in which the approximately 3,300 gallons of fuel were lost or stolen from the Custers’ station, Mobil had one of its field engineers test the tanks by filling them with water and then taking periodic measurements. By various measurements between July 18, 1979 and July 23, 1979, the engineer determined that some three inches of water had escaped, indicating that the 4,000 gallon tank was a “leaker”. He recommended to Mobil that because of a possible leak, and also because the tanks were then 25 to 30 years old, they ought to be removed. Other evidence showed that the same engineer tested the 4,000 gallon tank, with water, for a period of approximately one month, and the tank showed an approximate loss of over one foot and three inches of liquid.
It appears that the 4,000 gallon tank as well as the connected 2,000 gallon tank were removed from the ground on August 22, 1979. Several of the individuals who were present at that time and who visually inspected these tanks agreed that the only hole in them appeared to be near the top of the 4,000 gallon tank. One witness testified that the hole was about the size of a quarter to a half dollar. Those *248who testified agreed that the tank was rusted and pitted with corrosion. A representative from the Pennsylvania Department of Environmental Resources (“DER”) characterized the tank as being in “poor shape, fair to poor shape.” In response to questions during the course of hearings conducted by the lower court, witnesses acknowledged that even a careful examination of the tanks might not discover small holes that caused a leak, and that such small holes could expand, causing gasoline leakage, because of pressure exerted by the weight of fuel against the walls of the tank.
Also introduced in proceedings before the lower court were copies of notes taken by a claims adjuster for Mobil. In those notes, the Mobil representative indicated that he and an expert hired by Mobil in connection with this problem traveled around the area of the Custers’ station and located two other nearby service stations, which are identified as the Arco and Sunoco stations. The notes reflect that the expert concluded that because of their distance from Custers’ station, it was doubtful that the other two stations were responsible for the contamination which occurred.
The actual effects of gasoline contamination in well water in the area had been noticed by residents in the area as early as November, 1978. Residents of homes which were located down a hill and on either side of the Custers’ Mobil garage began noticing a change in the quality of their well water at that time, and some stated that it had an odor of gasoline. This change prompted the filing of complaints with the DER. That agency began sampling and testing the well water at eighteen separate locations in the Village, all in the general area of the Custers’ facility. These samplings began before the reported loss of fuel at the garage and continued until July 23, 1980. Not all of the wells were tested on each occasion of testing. Of the wells tested on August 22, 1979, four wells showed no gasoline contamination, whereas four wells had gasoline infiltration ranging from 1.5 to 20.0 parts per million. In testing on *249November 9, 1979, December 18, 1979 and April 3, 1980, three wells were not contaminated, yet nine had levels detected in the range from .8 to 20.0 parts per million. Samples taken on April 10, 1980 and July 23, 1980 showed that ten had no trace of gasoline, but nine registered petroleum pollutants ranging from .4 through 13.0 parts per million.
There was no evidence introduced of a particular state or federal standard establishing the level at which petroleum pollutants may be present in a water supply. However, proof was presented that a DER agent wrote to a resident in the area that while a small amount of petroleum product in well water might not be considered an eminent health hazard, it would make the water obnoxious to taste or smell, and therefore “unusable or undrinkable.” The DER representative further stated that any amount of gasoline or petroleum product in the water “should label that water as polluted.”
As a result of the problems in their water supply, the Appellees filed Complaints in trespass and equity against the Appellants in the Court of Common Pleas of Montgomery County. In all of the Complaints, the Appellees sought relief in the form of compensatory and punitive damages, as well as the implementation of the court’s equitable powers to abate and remove a nuisance. In the latter regard, the Appellees sought an injunction to restrain the Appellants from handling or mishandling gasoline so that it entered the source of the Appellees’ water. While admitting that Mobil was the owner of the storage tanks located at Custers’ service station, none of the Appellants admitted any of the other material allegations of the Appellees’ complaints. Thus, they denied that they caused or permitted gasoline to leak, spill or otherwise escape from the storage tanks, denied that they had acted in a reckless, negligent or careless manner, and denied that they had failed to inspect, maintain, supervise or correct conditions, or to recover and control gasoline after any spillage, leakage, or loss at Custers’ station so as to prevent its escape into the ground *250and thereby contaminate the Appellees’ water supply. In all ways, each of the Appellants denied liability or the responsibility for payment of damages under any theory of recovery. Each maintained that no gasoline had escaped from the tanks in question to invade the Appellees’ properties and to contaminate their water source. In New Matter, each of the Appellants sought indemnification from the other Appellants on theories of implied and/or expressed indemnity or precepts of trespass and assumpsit.
On November 21, 1980, counsel for the Appellees, in a petition for mandatory injunction, demanded relief including:
(a) That Defendants be restrained and enjoined from further polluting the Plaintiffs’ wells; (b) that a mandatory injunction be issued ordering Defendants to go upon the Plaintiffs land and gather, capture, filter, or otherwise remove from Plaintiffs’ wells the gasoline found therein in such a manner as not to cause further damage to Plaintiffs’ properties; (c) that Defendants, upon proof of same, be ordered to pay an amount of money necessary to place Plaintiffs’ land in the condition that it was prior to the improper conduct of Defendants, to pay any amount of money necessary for the replacement and/or repair of Plaintiffs’ properties and to pay a reasonable sum of money to Plaintiffs for Plaintiffs lose [sic] of use and enjoyment of said land; (d) that Defendants upon proof of same, be ordered to pay an amount of money reimbursing Plaintiffs for all costs and expenses including a reasonable attorney fee for the expenses they have incurred as a result of Defendants’ conduct; (e) such other relief as the Court deems proper and just under the facts as presented.
On December 16, 1980, the Appellees obtained an order of court setting January 5, 1981 for a hearing on the question of whether or not a preliminary mandatory injunction should be issued, pending a final hearing in the case. On December 22, 1980, a praecipe for civil trial list bearing the signatures of the counsel for both sides was filed, indicating *251that the case was in all respects ready for trial, but stipulating that discovery could continue until the case was listed for trial. Subsequently, interrogatories were filed on behalf of the Appellants, which had been answered by some of the Appellees. In addition, depositions were taken of the Custers, two Mobil representatives, and of the operators of the Sunoco and Arco stations situated in the vicinity of the Custers’ Mobil garage.
A hearing commenced before the lower court on February 6, 1981. Since the cases involved similar matters of proof, counsel for the various Appellees consolidated their efforts. They asserted that they planned to present evidence that the Appellants had polluted the Appellees’ wells with gasoline, and that there was enough evidence to justify the granting of equitable relief by the court. It is noteworthy that there was a consensus expressed among all involved in the hearing that the proceeding would deal with whether the Chancellor at that time could grant the “mandatory preliminary injunction” requested by the Appellees, and that the hearing would not involve questions leading to the calculation of damages claimed by the Appellees. The preliminary injunction hearing in this case consumed three days of testimony and generated a transcript of 528 pages. All of the Appellees who testified described their well water as being unpalatable and odoriferous. These conditions existed despite the fact that some had installed charcoal filtration or water softeners. Appellees also testified that they had experienced itching, dry skin, hives, and other problems as a result of use of the well water, and related that they had been forced to limit their use of such water to such things as flushing toilets and washing vehicles. They further related that their dishes and fixtures had become stained. Many described the odor as that of gasoline. In order to deal with these problems, some of the Appellees had to resort to the purchase of elaborate equipment or potable water, while others relied upon friends or relatives to provide them with water.
*252A number of witnesses testified concerning the issue of the source of the pollutants. As noted earlier, testimony came from employees of Mobil which indicated that the 4,000 gallon tank was a “leaker”, and that the surface of it was corroded and could be perforated without effort by an object such as a car key. As assistant professor of environmental science at Pennsylvania State University, who was hired by the Appellees, collected samplings from the wells and conducted tests on the samples. This witness testified that while he could not say for sure whether the 3,300 gallons of fuel at Custers’ facility was lost at one time or over a long period, he nonetheless believed that there was gasoline coming from that source. Further, he related that based upon his observations, tests, discussions with other experts, and other information, he did not believe that the gasoline had flowed into the Appellees’ water supplies from either the Arco or the Sunoco station. His conclusion was also based upon consideration of the terrain, the purported nature of the underground water table, and some rather inconclusive chemical testing.
An expert hired by Mobil to conduct his own investigation also testified. While it is clear that he took issue with some of the conclusions drawn by the Appellees’ witness, as described above, he also affirmed that during his investigation, he had reached a conclusion that it was “doubtful” that the Arco and Sunoco stations were responsible for the contamination due to their distance from Custers’ garage, and because no house in between their locations and the Custer location had reported well problems.
After concluding these hearings, the Chancellor decided to issue no preliminary injunction. Instead, he held settlement conferences with the parties. On February 26, 1981, after it appeared that attempts to settle the case would be unsuccessful, the Chancellor entered an order that a final hearing on the request for injunctive relief would take place on March 13, 1981. The Appellants filed various motions, including requests for discovery, for a continuance of 120 days, and for clarification of the Order setting the March *25313, 1981 hearing. The Chancellor denied these motions. At the subsequent hearing, at which only Russell A. Custer appeared on behalf of the Appellants, the Chancellor issued findings of fact and conclusions of law in support of a Decree Nisi. That Decree, inter alia: (1) permanently enjoined the Appellants from polluting the ground and the ground water in and about the vicinity of the Appellees’ wells; (2) ordered the Appellants to take such measures as might be necessary to assure that the gasoline and other contaminants presently in the soil and ground water as a result of the leakage from underground gasoline tanks in Custers’ garage would not pollute the Appellees’ wells; (3) required the Appellants to submit a comprehensive proposal to supply the Appellees with safe and potable water for domestic use, with such proposal to be prepared in consultation with Appellees’ expert consultant, with requirements that reports be submitted to the court concerning such efforts; and (4) directed the Appellants, “as a means of mitigating damages”, to provide the Appellees with an alternative supply of safe and potable water for domestic use.
The Appellants proffered over 300 exceptions in proceedings before the lower court, all of which were dismissed by the court en banc. Nine contentions of error are presented for our consideration in this appeal. We are constrained to find merit in several of the points raised by the Appellants.
We first address the Appellants’ complaint that the Chancellor improperly ordered, sua sponte, that the March 13, 1981 hearing be a “final hearing for injunctive relief” and improperly denied them the opportunity to engage in further discovery prior to that hearing. It does not appear that the Pennsylvania Rules of Civil Procedure specifically dictate when a final hearing must be held subsequent to a preliminary hearing on a request for an injunction. See Duggan v. 807 Liberty Avenue, Inc., 447 Pa. 281, 290, 288 A.2d 750, 755 (1972). Rule 1531(f)(1) makes it clear that a final hearing may be granted upon the demand of the *254defendant after the issuance of a preliminary injunction.2 However, the Rules do not establish any authority for a lower court to act, sua sponte, to order a final hearing.
In Hatalowich v. Bednarski, 315 Pa.Super. 303, 461 A.2d 1292 (1983), our Court recently reviewed a case in which the court entered an order of non pros sua sponte. It was held that the court’s order was in error because Rule of Civil Procedure 1037(c) only authorizes the court to enter such an ordér “on motion of a party”. Similarly, in Edward M. v. O’Neill, 291 Pa.Super. 531, 436 A.2d 628 (1981), this Court held that the trial court acted improperly in issuing an injunction sua sponte, when none had been sought by the plaintiff. The same conclusion as to the lower court’s sua sponte order for a final hearing is mandated in the instant case. Our finding of error is also compelled by the apparent possibility that the Appellants may have been prejudiced by the lower court’s denial of Appellants’ requests for further discovery and a delay in any final hearing on the injunction. Thus, we can only consider the lower court’s action as being valid, from a procedural view only, up to the time it denied a preliminary injunction after the initial hearings.
As a procedural matter, we could therefore remand this case for further proceedings, since it would ordinarily not be our practice to review a dispute involving such a preliminary order. However, because it is clear that there are other serious substantive problems regarding the lower court’s order in this case, we cannot serve justice by merely remanding on procedural grounds and ignore the fact that the lower court en banc affirmed obviously improper actions by the Chancellor. All such matters are covered by exceptions filed by the Appellants in the lower court and by arguments they have raised on this appeal. It is appropriate that we address these problems at this time.
*255In our evaluation of the propriety of the Chancellor’s order, our foremost concern is that he issued an injunctive order mandating significant affirmative conduct by the Appellants. It must be recognized that a mandatory preliminary injunction is an extraordinary judicial act and should be issued only in rare cases, and certainly more sparingly than an injunction which is merely prohibitory. Shanaman v. Yellow Cab Co. of Philadelphia, 491 Pa. 516, 421 A.2d 664 (1980); Roberts v. School Board of the City of Scranton, 462 Pa. 464, 469-70, 341 A.2d 475, 478 (1975). The court must exercise extreme care and act in only the clearest of circumstances. Roberts v. School Board of the City of Scranton, id., at fn. 4.
It is with such concepts in mind that we have reviewed the record. Our independent examination leads us to the firm conclusion that there were no apparently reasonable grounds for the court to conclude, with the requisite assurance necessary for the issuance of a mandatory injunction, that the Appellants’ gasoline tanks were the cause, or especially the sole cause of the contamination of the Appellees’ ground water supplies. This finding by the lower court was clearly speculative in the absence of any evidence of leakage testing of the similar tanks used by the other gasoline stations in the same area. It simply cannot be determined with assurance that either or both of those facilities were not the source or partially the source of the petroleum pollution. The conjectural nature of the lower court’s finding as to the Appellants’ culpability for the contamination does not permit us to sustain the issuance of an extraordinary mandatory injunctive order in this case.
It is also apparent that two particular aspects of the lower court’s mandatory order are legally improper, even if one were to find validity in the lower court’s conclusion that the Appellants were responsible for the contamination of the Appellees’ wells. First, the court’s order that commanded the Appellants to cease polluting the Appellees’ grounds and ground water was inappropriate because the evidence showed that the Appellants had already removed *256the tanks which were allegedly the source of the leakage and replaced them with new ones. One cannot imagine any further steps the Appellants could take to assure no further seepage of their petroleum into the ground. Since the possibility of continuing seepage was thereby prevented, the court had no reasonable basis for including such a mandate in its order.
Second, we must hold improper that part of the lower court’s order requiring that the Appellants implement measures necessary to assure that the gasoline and other contaminants already in the soil and ground water did not continue to pollute the Appellees’ wells.3 It is evident from the evidence of record that a workable and scientifically proven solution to the problem of continued subsurface seepage of gasoline already in the ground into the Appellees’ water supply is uncertain.4 The only alternatives *257offered by the parties gave no guarantees of success. It is clear that the lower court has therefore required the Appellants to take action that appears to be impossible to accomplish. We cannot affirm such an order.
We are certainly troubled by the great inconvenience and significant harm which has been visited upon the Appellees by the reprehensible pollution of their potable water supplies. The constant difficulty and hardship of living with this condition cannot be ignored or minimized. However, our cognizance of their plight does not lead to the conclusion that the lower court’s clearly excessive and improper exercise of equitable powers should be affirmed.
This matter should have been certified to the law side of the court. The harm suffered by the Appellees can be fully remedied by an award of damages. In that regard, we note that the lower court’s order requires the Appellants to provide the Appellees with potable water supplies. Yet, the record shows that most or all of the Appellees had already been procuring their own safe water supplies for a significant time prior to the initiation of this litigation in the lower court. The Appellees could be adequately compensated through an award of money damages for both actual expenses they incurred in such efforts as well as for any inconvenience involved in the process, both before and after the date of the hearings in the lower court. Likewise, they can be fully compensated by receiving damages for the loss in the value of their properties, homes, and water supplies, as well as for the harm and inconvenience they have suffered in the past and may suffer in the future. The availability of an adequate remedy at law makes it clear that equitable relief of the type granted by the lower court should have been withheld.
*258The Order of the lower court is reversed and this case is remanded to the lower court with directions that it be certified to the law side of the court for further proceedings.
Jurisdiction is Relinquished.
POPOVICH, J., files a dissenting opinion.. The findings of fact of the chancellor who heard the testimony without a jury, which are subsequently approved by the court en banc, are entitled to the weight of a jury’s verdict; such findings are controlling unless they lack evidentiary support or it is evident that the chancellor capriciously disbelieved the evidence. See Hankin v. Hankin, 279 Pa.Super. 179, 196, 420 A.2d 1090, 1099 (1980). We rely on the Chancellors’ findings in relating the facts in the instant case.
. For interesting guidance-in this area, see School District of Pittsburgh v. Pittsburgh Federation of Teachers, 486 Pa. 365, 374, 406 A.2d 324, 328 (1979).
. The court ordered the Appellants "... to take such measures as may be necessary to assure that the gasoline and other contaminants presently in the soil and ground water as a result of the leakage from the underground gasoline tanks in Custer's Garage does not pollute plaintiffs’ wells.” (emphasis added).
. Section 839 of the Restatement (Second) of Torts is directed to the liability of a possessor of land for a nuisance — a nontrespassory invasion of another’s interest in the private use and enjoyment of land — caused while he is in possession, by an abatable artificial condition on the land. It appears applicable here, particularly in recognition of the pertinance of Comment f, and Illustration 1 thereto, which explain what is meant by the words “abatable physical condition”:
"†. Abatable physical condition. By an ‘abatable physical condition’ is meant one that reasonable persons would regard as being susceptible of abatement by reasonable means. The law does not require the unreasonable or fantastic, and therefore even though it might conceivably be possible to abate a particular condition, it is not ‘abatable’ within the meaning of this Section unless its abatement can be accomplished without unreasonable hardship or expense.
Illustrations:
1. A is in possession of land upon which is situated a tank for the storage of petroleum. B is in possession of land 500 yards from this tank. Without A’s knowledge or negligence the tank develops an underground leak and a quantity of oil flows out, saturates A’s land and drains into an unknown subterranean stream that carries it to B’s land. As a result, B’s well that supplies his drinking water *257is polluted and rendered unfit for use. When A learns of this he immediately removes all the remaining oil from the tank but the oil already in his land continues to pollute B’s well for some time. It is found that A’s maintenance of the oil tank was not abnormally dangerous. A is not liable to B for failing to take action to remove the oil already in his land, since it would not be practicable to do so.