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Approved Area & System Type Soil test pits and other site features were evaluated during the site visit on June 12,2008. The conditions observed during this site evaluation indicate that the area around the evaluated test holes is not capable of supporting a Standard septic system due to the following limitation: Temporary groundwater level is too close to the ground surface DEQ Rule requirement: Temporary groundwater level cannot come within 24"of ground surface for a Standard system. "Temporary groundwater" refers to a water table that completely dries up during certain times of the year. OAR 340-071-0220(1)(b)(B) Description: Treatment of sewage occurs in the soils around the drainfield area. If groundwater comes in contact with the sewage before it has been adequately treated in the soils,there are two concerns: 1) very little treatment occurs in saturated soils—the presence of air is required for good treatment;and 2) sewage may be"forced"to the surface where it poses a potential public health hazard. Not enough effective soil depth DEQ Rule requirement: 30"+soil required(depending on slope)and a minimum of 6"from bottom of the drainfield trench to layer that limits effective soil depth. OAR 340-071-0220(1)(a) Description: "Effective soil depth"is defined as"...the depth of soil material above a layer that impedes movement of water, air, and growth of plant roots. Layers that differ from overlying soil material enough to limit effective soil depth are hardpans,claypans,fragipans,compacted soil,bedrock,saprolite, and clayey soil." Soils provide an important part of the treatment and"sanitizing"process for sewage. However, this treatment by the soils requires air to penetrate. The problems caused by not enough effective soil depth: poor treatment of the sewage,and sewage being forced to the ground surface where it is a public health hazard. Under the conditions observed at the above address,an ALTERNATIVE SYSTEM is required by DEQ rules for both the INITIAL and FUTURE REPAIR systems. Please refer to the signed approved site plan dated April 3, 2009. Alternative systems include SAND FILTERS, RECIRCULATING GRAVEL FILTERS, and ALTERNATIVE TREATMENT TECHNOLOGIES. Alternative systems are installed where soil, drainage,water table levels,or space limitations do not allow for a standard system installation.The unit pre-treats the septic tank effluent before it is discharged into the ground. Specific Requirements AN EFFLUENT LIFT PUMP WILL BE REQUIRED to install the septic system disposal field in the approved area and at the required depth.Detailed instructions for dosing tank/effluent pump installations are available in our office. The electrical wiring to the pump and alarm must be installed in accordance with the appropriate Electrical Code.The electrical work must be done under a Marion County Electrical Permit and must be inspected and approved by a Marion County Electrical Inspector.The work must be left uncovered and accessible for inspection.The electrical inspection includes the connections to the pump and alarm in the dosing tank, the wiring in the trench and the connections in the structure. A CURTAIN DRAIN (GROUNDWATER INTERCEPTOR) IS REQUIRED as part of this system to divert groundwater from the drainfield. The curtain drain trench must be constructed a minimum12 inches wide by 42 inches deep with 30 inches of clean gravel placed over a 4 inch perforated pipe (ASTM Specification F 405,D 2729 or F 810). Gravel must be placed a minimum of 2 inches under the 555 Court St NE - P.O.Box 14500-Salem,Oregon 97309-5036-Phone(503)588-5147-Fax(503)588-7948 Page 2 of 4