Opinion by
As the noted legal luminary, Karl Lléwellyn, once said, “Law . . . begins when someone takes to doing something someone else does not like.” These words seem particularly appropriate in this case which is an appeal from an adjudication of the Sanitary Water Board (Board) which,1 over appellants’ objections, *112granted a permit to Kristianson & Johnson Coal Co., Inc. (K. & J.) for the discharge of industrial waste and mine drainage from a proposed bituminous coal strip mine in Chest Township, Clearfield County, and Chest Township, Cambria County. The mine drainage application, filed on May 25,1970, pursuant to the then applicable Section 315 of the Clean Streams Law, Act of June 22, 1937, P. L. 1987, as amended by the Act of August 23,1965, P. L. 372, embraced 1,707.19 acres, but the total “land affected”2 by such mining would be 1,-273.15 acres of the watershed of Rogues Harbor Run, a tributary of Chest Creek.- Rogues Harbor Run is the source of trout fishing enjoyment for many members of the organizations here represented, as well as the source of water supply ..for the Westover Water Authority, which supplies water for the use of Westover Borough, a community in Clearfield County with an approximate population of 500.
.The primary contention of appellants is that the proposed K. & J. strip mine operation will cause sedimentation which will degrade the quality of Rogues Harbor Run as a fishing stream and adversely affect it as a domestic water supply for Westover Borough.
*113The Ilian of operation of K. & J., after being made subject to 26 “Standard Conditions” and six “Special Conditions”, was approved by the Department of Mines and Mineral Industries, the reporting agency3 for the Sanitary Water Board. The Board unanimously adopted the favorable recommendation of its reporting agency on July 15, 1970, and approved the issuance of a permit, but because the Board had been advised of the objections of various groups to the granting of a permit, the permit was withheld and hearings followed on August 4, 20, and 21, and September 21 and 22 at which testimony and exhibits were received from K. & J., the protestants, and the Department of Mines and Mineral Industries. On January 18, 1971, the Board issued the adjudication and order appealed from here. Appellants wish us to set aside the Board’s decision and to remand the matter to the Board “for further proceedings consistent with the provisions of Act No. 222” (the Act of July 31, 1970, P. L. , No. 222, 35 P.S. §691.1 et seq-)-
Intervening appellee, K. & J., filed a Motion to Quash on April 13, 1971, to which an Answer was filed by appellants on April 27, 1971. We conclude that the contentions made in the Motion are without merit, and therefore it is denied.
Turning to the merits, appellants make the following contentions:
(1) Contrary to the weight of thé evidence, which proved that sedimentation would enter the stream, the Board decided that the proposed operation can be con*114ducted without resulting in pollution4 of Rogues Harbor Run.
(2) The Board erred in finding that KL & J.’s mining operations under another permit at nearby Rock Run Creek do not provide a basis for determining whether it could properly operate the proposed operation.
(3) The Board erred in permitting EL & J. to file less than a complete set of plans.
As to the first contention, appellants acknowledge that “If this sedimentation was excessive, it would be harmful to aquatic life and to the use of the stream as a domestic water supply. Thus, the question is whether the sedimentation that would in fact occur might become excessive." (Emphasis added) On this point, appellants point to the testimony of Mr. David Yost, a soil scientist with the Soil Conservation Service, to the effect that he had made a study of the soils in the Rogues Harbor Run area and had calculated that “for a five year frequency storm, from 93,367 to 107,650 cubic yards of silt loam would be moved into Rogues Harbor Run if no vegetation is planted prior to the storm." (Emphasis added) This study, however, was based on a formula from a technical manual used by the Soil Conservation Service. In applying the formula, which was marked “tentative” and published in *115March, 1970, Mr. Yost testified that it was assumed that the entire area would be bare and have no vegetation, that if vegetation was present that a different formula would have to be used, and that he had not examined the plan of operation or given consideration to the diversion ditches, the planting that is to be required under the plan as stripping progresses or other controls that were set forth in the plan.
We are hardly stream pollution experts, and, as the Supreme Court’s words in Blumenschein v. Housing Authority of Pittsburgh, 379 Pa. 566, 572-573, 109 A. 2d 331, 334-335 (1954), indicate,5 our review is limited, but we tend to agree with appellee that “Siltation is not a problem for which standards may be easily established and enforced. Some silt may be useful to a stream, but the precise point at which it becomes harmful is not clear. Nor are many of the common sources, such as plowing of farm fields, adequately controlled. Nevertheless, it is known that excessive silt in a stream is definitely injurious to certain types of aquatic life, and flagrant examples of excessive siltation may be readily recognized. Consequently the best way to deal *116with the problem, at this time, is to require that meaningful preventive safeguards be incorporated in any plan .of an operation where the potential for excessive siltation exists. K. & J., the applicant in this case, has made a concerted effort to devise such preventive measures ; in fact, one of the best proposals yet received by the Department.” (Emphasis added)
As to the second contention, it would appear that K. & J. has significantly changed its plan of operation for the present tract as opposed to its methods .at the Rock Run Creek location. As appellee points out, “. . . K. .& J.’s proposed operation on Rogues Harbor Run differs in two major particulars: (1) all haul roads are to be constructed on the spoils of the operation or at an elevation higher than the mined areas, whereas in the Rock Run operation there were no conditions on the location of the haul roads. To the extent there was any problem with siltation on that Rock Run operation, it was due to the silt in the drainage from the haul roads, which were constructed below the mined area. This drainage reached the stream without any settling. This situation has been remedied by the building of settling ponds intermittently along the haul roads to direct the drainage in the ditches from the stream temporarily to enable settling of silt to occur. (2) The mining is to progress in a checkerboard fashion, Avhich significantly decreases the possible area exposed at any one time. In any event, K. & J. was never found to be in violation on its Rock Run operation, and the latest biological study of the stream in July of 1970 revealed that Rock Run is progressly improving in its ability to support aquatic life.”
Appellants’ third contention is urged because the plans “did not show the annual waterfall, composition of the soil, slope of the land, or quantity of water which Avill drain over, around and through the proposed min*117ing operation.” This information was not' required, however, and, in the. Board’s educated opinion, not particularly helpful.6
*118In this proposed operation, in the opinion of the Board, provisions have been made for the control of all the potential sources of excessive siltation from this proposed mining operation. “We must say with respect to this finding that it is the primary function of the Sanitary Water Board to protect the waters of the Commonwealth for the benefit of all the people. From the time The Clean Streams Law was first passed in 1937 the Sanitary Water Board has made many investigations into the various aspects of pollution and we feel that the board thereby has acquired a special knowledge and competence with regard to these matters.” Sanitary Water Board v. City of Wilkes-Barre, 78 Dauph. 328, 334, aff’d, 199 Pa. Superior Ct. 492, 185 A. 2d 624 (1962). “[T]he Administrator’s policies are made in pursuance of official duty, based upon more specialized experience and broader investigations and information than is likely to come to a judge in a particular case. . . . We consider that the rulings, interpretations and opinions of the Administrator . . ., while not controlling upon the courts by reason of their authority, do constitute a body of experience and informed judgment to which courts and litigants may properly resort for guidance. The weight of such a judgment in a particular case will depend upon the thoroughness evident in its consideration, the validity of its reasoning, its consistency with earlier and later pronouncements, and all those factors which give it power to persuade, if lacking power to control.” Skidmore v. Swift & Co., 323 U.S. 134, 139-140, 65 S. Ct. 161, 164 (1944), cited with approval in Hogan Unemployment Compensation Case, 169 Pa. Superior Ct. 554, 558-559 n.2, 83 A. 2d 386, 389 n.2 (1951) (“When an administrative board rests its conclusion upon its own official experience the courts generally respect its special competence.” (Emphasis in original)).
*119We fully understand appellants’ concern that this proposed strip mine is likely to be “. . . harmful or inimical to . . . aquatic life [of Rogues Harbor Run], or to the. use of such waters for domestic water supply . . but at this point (1) we have faith in the Board’s acumen in these matters and feel that it has thoroughly considered this matter (particularly so because it is hypertensively involved in ecological improvement in the Commonwealth), and (2) we rely heavily that “Special Condition” No. 2 (that, as an additional safeguard, “prior to activating of this mining operation, ... all facilities shall be inspected and approved by the District Mine Inspector ....”) will effectively cure any defects in the operation plan, and that subsequent inspections (which in the past have been approximately weekly or biweekly) in accord with the provisions of the Bituminous Coal Open Pit Mining Conservation Act, supra, will do the same.
We applaud the civic spirit demonstrated by the several appellants, but we nevertheless fail to find the requisite “manifest and flagrant abuse of discretion or a purely arbitrary execution of the agency’s duties or functions.”
Order affirmed.