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Septic Site Evaluation 555-18-007043-EVAL Page 4 of 6 Datec' ued: 10/5/20t8 gFOR,.rittir a 4- .......... General Description of Site Evaluations Sewage contains disease-causing organisms and other pollutants that can cause adverse impacts to human health and the environment. An onsite sewage disposal system must treat and dispose of sewage in a way that will not cause a public health hazard, contaminate drinking water supplies,or pollute public waters. _ Proper treatment in an onsite system begins with primary treatment in the septic tank. The septic tank separates the solid particles in sewage from the liquid. The liquid that comes out of the septic tank is called effluent. The effluent may then be dispersed in the soil for further treatment or discharged into a secondary treatment device such as a sand or gravel filter or other alternative treatment unit prior to dispersal in the soil. For proper treatment,the effluent must slowly infiltrate into the underlying soil. Dissolved wastes and bacteria in the effluent are trapped or adsorbed to soil particles or decomposed by microorganisms. This process removes disease-causing organisms, organic matter, and most nutrients. Effluent that comes to the ground surface(through poor soils or other problems with the system)can be a possible health hazard because it may still contain some disease-causing organisms. Soil that drains too quickly may not give the effluent enough treatment and may result in groundwater contamination. The purpose of the evaluation is to locate suitable soils in an area that is large enough for both the initial drainfield area and the replacement drainfield area. The criteria used for this site evaluation can be found in Oregon Administrative Rules (OAR)340-071. In the site inspection,the following features are evaluated: •❑❑❑❑❑❑❑❑Soil types-how well they drain and other indicators of good soil structure for treatment •❑❑❑❑❑❑❑❑Depth to evidence of groundwater •❑❑❑❑❑❑n❑Wells located on the site or adjacent sites •❑❑❑❑❑❑❑❑Slopes,escarpments,ground surface variations,topography •❑❑❑❑❑❑❑❑Creeks or springs on the site or adjacent properties •❑❑❑❑❑❑❑❑Whether the soils have been disturbed •❑❑❑❑❑❑❑❑Setbacks from property lines, buildings,water lines, and other utilities •❑❑❑❑❑❑❑❑Other site features that could affect the placement of your onsite system Approved Area&System Type Soil test pits and other site features were evaluated during the site visit on October 1,2018.The conditions observed during this site evaluation indicate that the area around the evaluated test pits IS NOT CAPABLE of supporting a Standard septic system due to the following limitation: Not enough effective soil depth DEQ Rule requirement: At this site,a Standard septic system requires an effective soil depth of 42 inches on a 24% slope. "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." OAR 340-071-0220(1)(a) Description: 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. Due to the shallow depth a vertic clay horizon observed in the test pits at this site,an ALTERNATIVE SYSTEM is required by DEQ rules for both the INITIAL and FUTURE REPAIR systems. At your site ALTERNATIVE TREATMENT TECHNOLOGY Treatment Standard 1 will meet DEQ rules.The effective soil was found to be between 12 and 29 inches in the test pits. Please refer to the signed approved site plan dated October 2,2018. Alternative Treatment systems include Sand Filters, Recirculating Gravel Filters and Alternative Treatment Technologies CALL BEFORE YOU DIG...ITS THE LAW ATTENTION:Oregon law requires you to follow rules adopted by the Oregon Utility Notification Center. Those rules are set forth by Oregon Administration Rules. You may obtain copies of the rules by calling the center.(Note:The telephone number for the Oregon Utility Notification Center is 1-800-332-2344.) 5/30/19:12:24:16PM Page 4 of 6 ONS_OnsiteEvaluation_pr