(1) Through well data collected since 1958 and refraction seismic surveys conducted in 1970 and 1971, the department of ecology has identified a semiclosed groundwater basin in the area of Duck Lake in Okanogan County, Washington.

(2) The principal aquifer in this area consists of glacial and fluvial sands and gravels that lie unconformably over metamorphic and igneous bedrock.

(3) Natural recharge to the aquifer occurs primarily through groundwater migration from Johnson Creek Valley which lies northwest of the Duck Lake basin.

(4) The aquifer is also artificially recharged through waters diverted to Duck Lake from Salmon and Johnson creeks by the Okanogan irrigation district and from waters incidental to irrigation of project lands.

(5) Since the basin retains substantial quantities of artificially stored groundwater, in accordance with chapter 90.44 RCW it has been recommended that the Duck Lake aquifer be designated as a groundwater subarea.

The purpose of this regulation is to establish areal boundaries for the Duck Lake groundwater subarea as the initial step toward development of an appropriate groundwater management program for this area.

This regulation is promulgated by the department of ecology under authorities and procedures provided in chapters 43.21A, 90.03 and 90.44 RCW and after giving notice as provided in chapter 34.04 RCW.

"Duck Lake groundwater subarea" shall mean those lands lying within Okanogan County described as follows:

Beginning at the west quarter corner of Sec. 23; thence northeast through the north quarter corner of Sec. 23 and the east quarter corner of Sec. 14 to the north quarter corner of Sec. 13; thence east to the northeast corner of Sec. 13; thence north to the east quarter corner of Sec. 12; thence northwest to the southeast corner of Sec. 2; thence northwest to the center of the northwest quarter of Sec. 2; thence southwest through the west quarter corner of Sec. 2 to the south quarter corner of Sec. 3; thence west to the southwest corner of Sec. 3; thence south along the west line of Sec. 10 to the "bedrock" exposure which lies approximately 1,300 feet north from the southwest corner of Sec. 10; thence southeasterly along the "bedrock" to the south quarter corner of Sec. 10; thence south 1,320 feet; thence west 1,320 feet to the center of the northwest quarter of Sec. 15; thence south 3,960 feet to the south line of Sec. 15; thence east to the south quarter corner of Sec. 15; thence southeast to the point of beginning; all in T. 34 N., R. 26 E.W.M., Okanogan County.

"Duck Lake groundwater subarea" shall include those lands that lie within the heavy outline shown on the following map:

The department of ecology shall initiate a review of the rules established in this chapter whenever new information, changing conditions, or statutory modifications make it necessary to consider revisions.