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• Marton County OREGON Marion County Building Inspection 5155 Silverton Rd.NE Salem, Oregon 97383 Prepared For: Patrick Bartshe 127 Gates Hill Rd. SE Gates, Oregon 97383 093E27DA01100 Winter Water Monitoring Summary Test Pits were observed on June 5 and June 12, 2018 in response to an application for a Site Evaluation at 127 Gates Hill Road SE, Gates. An observation concluded that the soil in the pits showed evidence of a permanent water table at a depth that was unable to be determined at the time. The site required winter water monitoring to ensure that the site was capable of septic approval. Methods Used: Ports approximately 12" in diameter were prepared and backfilled with gravel surrounding a 3" perforated length of pipe. The ports were approximately 5-6 feet deep and had risers above the surface open for inspection. The ports were within 6" of elevation difference. Twice a week, beginning in early November, 2018 and ending on April 29, 2019, an agent from Marion County observed the height of the water in the observation ports. Weather data was gathered from NOAA's weather.gov website and recorded in 72 hour increments preceding each visit. For further detail, please refer to the table and graph that accompany this report. The soil observed in the ports fell into Soil Group C, Per OAR 340-071-0220 table 5 (Silty Clay—Sandy Clay). Per OAR 340-071-0290(2)(b)(A)(iii),the permanent water table must have remained at a depth of 24" or greater for approval of any type. Conclusions: Aside from major precipitation events,the level of the water was not observed to be at denial depth in either port. Port#2 averaged a slightly deeper depth to the water by about 1.5 inches. The geographical area experienced slightly below average precipitation for the season, with peak events in late December and early April. This data allowed us to conclude that the permanent water table is evident around 30"below the surface, which correlates with the redoximorphic features originally observed in both test pits near similar levels.