Loading...
HomeMy WebLinkAbout1978 Percolation Test Reportm REPORT ON PERCOLATION TESTING FOR STIELOW'S ADDITION ORONO, MINNESOTA Prepared By Eugene A. Hickok & Associates Wavz^a /^Hay, 1978 J I. Introduction and Summary We have completed a program of percolation testing for the proposed Stielow addition. The legal description of this parcel of land is: Lots 1, 2, 3, 4, 5, 6, and If Auditor's Subdivision Number 207, Hennepin County, Minnesota. All work was performed in accordance with the requirements of the City of Orono, Hennepin County and the State of Minnesota. _ _ _ _ _ _ _ ir - - - - - - - - - - ' ~ " "■ The proposed lots with the exception of lots 1, 9 and 11 were found to have soil conditions suitable on-site sewage disposal systems II. Scope of the Testing Program The scope of this testing program is intended to fulfill the City's requirements for subdivision plat approval. It will also result in percolation tests sufficient for building permit application and the design of individual on-site sewage disposal systems. Testing was performed in accordance with the applicable City ordinance and the requirements of Hennepin County and the State of Minnesota. A soils report and map were prepared by Hennepin Soil and Water Conservation District and is included herein as Appendix A. We began our work by studying this report to determine the location of the soils ■ most suitable for on-site sewage disposal systems. He also studied the proposed plat and topographic map to determine how the locations of the homes, wells, and drainfields would best be located on each lot. These proposed locations are shown on Figure 1 and are considered preliminary. At the time that building permits for each particular lot are applied for, final locations of these * site features will be set; of course, the drainfields must be constructed on the locations tested unless another test is made. Our field work included drilling six percolation test holes and three soil borings for each lot. All of the percolation test holes were six inches in diameter and three feet deep. Each of the soil borings were eight feet deep. As each hole was drilled, a record was made of' the soils encountered. All of the soils information which we developed was added to that of Hennepin Soil and Hater Conservation District and a revised soils maps was prepared for the site. The depth to the water table was recorded when encountered. Percolation tests were performed in accordance with WPG 40 of the State of Minnesota. The details and results of the test are discussed for each lot separately below. I i Lot Eleven The soils on lot eleven include Hamel Loam and Lester Loam. The first is not suitable for drainfields; the Lester soil is. Our testing encountered the Lester and Hamel Loam soils. The average percolation rate for the pri­ mary drainfield site was 111 minutes/inch and 6.8 minutes/ inch for the secondary site.- The water table was encountered at a depth of from 2.5 to 3.5 feet. The percolation rate for each test hole is listed in Table 1. The soil boring logs are listed in Table 2. This lot is being retested to find another locatioii suitable for a drainfield._ _ _ _ __ Lot Twelve The soils on lot twelve include Hamel Loam, Glencoe Silty Clay Loam and Lester Loam. The first two are not suitable for drainfields; the Lester soil is. Our testing encountered Lester Loam soil. The average percolation rate for the primary drainfield site was 8.3 minutes/inch and 9,9 minutes/inch for the secondary site. The water table was encountered at a depth of four feet in one boring and not encountered to a depth of eight feet in two other borings. IV. Overview of Results s k II All of the lots except lots 1, 4, 9, soil and site conditons which ace suitable for on-site conditions which are suitable for on-site sewage disposal. The tests were located at what we consider to be the best sites for the construction of the drainfields. This is not to say that other sites are not suitable. It is recognized that as homes are built on the lots, other sites may be desireable for various reasons. This report can be used as a guide in evaluating other sites on each lot, of course another percolation test would be required if another site were proposed. Stated percolation rates are averaged for the location shown, and no guarantee is implied or expressed that these conditions exist for the entire area. Table I cont. TB8T HOLB LOT 9 9-1 9-2 9-3 9-4 9-5 9-6 LOT 10 MATERIAL Lester Loam Lester Loam Lester Loam Lester Loam Lester Loam Lester Loam Lester Loam Lester Loam Lester Loam Lester Loam Lester Loam Hamel Loam Lester Loam Lester Loam Lester Loam Lester Loam Hamel Loam Lester Loam PERCOLATION RATE 19.2 min/in 250.0 min/in 250.0 min/in 125.0 min/in 31.3 min/in 125.0 min/in 4.0 min/in 41.0 min/in 83.3 min/in 125.0 min/in 6.0 min/in 27.7 min/in 50.0 min/in 250.0 min/in 83.3 min/in No Percolation 83.3 min/in 3.6 min/in 12-1 Lester Loam 13.2 min/in 12-2 Lester Loam 3.5 min/in 12-3 Lester Loam 19.2 min/in 12-4 Lester Loam 15.6 min/in 12-5 Lester Loam 62.5 min/in 12-6 Lester Loam 20.8 min/in Lot 13 13-1 Lester Loam 62.5 min/in 13-2 Lester Loam 19.2 min/in 13-3 Lester Loam 125.0 min/in 13-4 Lester Loam 125.0 min/in 13-5 Lester Loam 83*3 min/in 13-6 Lester Loam 25.0 min/in Soil Boring Table cont. 12B Olive brown silty clay loamr mottled with rust below 2.0*, with some gravel Water table 2.S' below surface 0-1.0* Black silty loam 1.0-8.0*Olive brown silty clay loam, mottled with rust and gray clay below 2.5' Water table 3.5* below surface 0-0.5* 0.5-4.5* 4.5-8.0* Black silty loam Olive brown silty clay loam mottled with rust and gray clay below 3.0* Light olive brown silty clay loam, with some sand, mottled with rust and gray clay Water table was not encountered within 8* of the surface 0-0.5* 0.5-1.0* 1.0- 4.O' 4.0- 8.O' Black silty loam Grayish brown silty clay loam Olive brown silty clay loam Light olive brown silty clay loam, with some sand, mottled with rust Hater table was not encountered within 8* of the surface.