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HomeMy WebLinkAboutTract 02A January 3, 1978 Phyllis Janke Post Office Box 567 Eagle River~ Alaska 99577 Subject: Tract 2A Itighland Hills Subdivision Permit ~77942 A permit issued by this department for well and/or sewer system has expired° Permits are issued on a calendar year basis~ as stated on the permit~ by authority of Municipal ordinance° If you have drilled the well, a well lo,q should be sent to this department to document the installation date. If there are any further questions, please contact this office at 264-4720. Sincerely, Health and Environmental Protection Sewer and Water Section 4040 "B" STREET, ANCHORAGE, ALASKA 99503 PHONE: 907-279-2581 October 10, 1977 W.O.#: A18270 Joe Janke South Side Eagle River, Alaska Subject: Subsurface Investigation for suitablity of On--Site Sewage Disposal System; Lot 22, Block 2, Highland Hills #4 -AND-Highland Hills Itl, Rural Residence Dear Mr. Janke: This report gives the results of the above subject investigation as performed by us on October 7, 1977. The scope of the investigation was to determine the suitability of the sites for the installation of an on-site sewage disposal system. Included in this report are: Test Hole Location Sketches Test Hole Logs Explanatory Information Figures 1 and 2 Tables A and B Sheets 1-3 The investigation consisted of a visual classification of soils exposed by test pi_ts, previously dug by back--hoe. Soils classification was performed by Alaska Testlab geologist. Logs of the test pits are included as Tables A and B of this report. In interpreting the logs, it would probably be helpful to use the explantory information of Sheets 1-3 of this report. Conclusions and Reco~nendation: Lot 22, Block 2, Highland Hills #4: Our investigation of this property indicates the high ground where the test pit was located is ideally suited for the installation of an on-site sewage disposal system. Soils are gravely sand and sand, with no evidence of a water table. Soils of this type require a seepage pit abso]~tive area of 100 square feet per bedroom (gravel sand) and 125 square feet/bedroom (sand), respectfully. October 10, 1977 W.O.#: A18270 Page 2 Highland Hills ~1, Rural Residence: Our investigation of this property indicates the area where the test pit was located may possibly be used for the installation of an on-site sewage disposal system. A 3.5 feet layer of very dense sandy gravel overlays a gray, plastic, silty gravel. The underlaying material appears unsuitable; however, the course, clean upper layer of sandy gravel could possibly be used. If your further work in this area indicates the sandy gravel soil is thicker (deeper) than as shown by the test pit, this would improve the possibility of construction the disposal system. Soil of this type requires a minimum of 85 square feet per bedroom absorptive area in the seepage pit, or leach lines. Because of the dense nature of this poll at this location you may wish to use a slightly more conservative figure of 125 square feet/bedroom. No water table was observed during the investigation of the 'test pit. It should be noted though, the free water level normally fluctuates seasonally and with precipitation. We hope this report meets y6ur needs. If we can be of further service, please contact us. Very truly yours, ALASKA TESTLAB T. A. Sexton APPROVED BY: /~ Melvin R. Nicl~ol~, P.k. TAS/tsc PIT CLz[-~/v'T'.' .J-o~ JAi'JK~_ MX, O, p/~oJ~c.'r; /-oT 22__ ' t~llf 2__.. ,~4 ,'~ 4 I,,,,2 /-/, ~ / ~ZTO T0 P SOIL. "i 7'~ ,~ ?' PIT~..) rOLl-El'VT .. pT< od ~c T: 0 ! Zl, .5 II .,so;/ GC.-C,L A£'f':A Test Hole Loi]l - Description Guide The soil descriptions shown on the logs are the best estimate of the soil's characteristics at the time of field examination attd as such do r~ot achieve the precision of a laboratory testing procedure. If the log includes soils samples. those samples receive an independent textural classification in the laboratory to verify the field examination. The logs often include thc following items: Depth interval - usually shown to 0.1 foot, within that zone no significant change itl soil type was observed through drill action, direct observation or sampling. Frost Classification NFS. Fl, F2. F3. F4, see "Soil Classification Chart" Texture of Soil ~ An engineering classification of tile soils by particle size and proportion, see "Soil Classification Chart". note the proportions are approximate and modifications to the soil group due to stratification, inclusions and changes in properties are included. Moisture Content - this is a qualitative measure: dr.S_, no or little apparent surface moisture, damp, moisture forms portion of coio~, less than plastic Ii/nit, 16ke.~, no free water, often soft, if cohesive soil saturated, free water may be squeezed out, ifa free draining soil; ~'~ at natural moisture content, if a non-plastic silt or fine sand. {Thc moisture content is further definedby reference to PI, LW, NP, M%or dilatency.} Density refers to ]nore-or-less non-cohesive soils, such as sand gravel mixtures with or without a fine fraction, derived from drilling action and/or sample data; usually described as: very loose, loose, medium dense, very dense. Genera] intent is to portray earthwork characteristics. Stiffness refers to more-ordess cohesive soils and fine grained silts of ~2y-silt groups. Derived from drill action and/or sample data. Very soft, soft, stiff, very stiff and hard are commonly used terms. Particle size - The largest particle recovered by the split spoon is 1-3/8", Shelby tube Y', auger flights (minute-man) 2", Auger flights (B-50 hollow stem) 6"-8". Larger particles are described indh-ectly by action of the drilling and are referred to as cobbles, 3" to 8", or boulders 8"+. Therefore when reviewing the gradation sheets, if any, the description on the hole log ~nust be considered for an indication of larger particles. Unified Soil Classification ~- This is a two letter code. See Unified ~~ther definition, ht some cases AASHO and/or FAA soil classifications may be shown as well as the unified. Atterberg Limits - useful for fine grained and other plastic soils, P_l; natural moisture content believed to be less than plastic limit PI+; natural moisture content believed to be between plastic and liquid l~mit s L~w+; natural moisture content believed to be greater than liquid limit N~P; non-plastic, useful as a modifying description of some silty mat~brials, Dilatency_ - is the ability of water to migrate to the surface of a satm-ated or nearly saturated soil sample when vibrated or jolted - used as an aid to determine if a fine grained soil is a slightly or non-plastic silt or a volcanic ash, Rock flour finely ground soil that is not plastic but otherwise appears similar to a clayey silt. Organic Content - usually described as Peat, PT, sometimes includes discr~-~ p~ such as wood, coal, etc. as a modifier to an inorganic soil. Quantity described as; trace, or an estimate of volmne, or, in case of all organic, - as Peat. This may include tundra, muskeg and bog material, Muck - a modifier used to describe very soft, semi-organic deposits u-~]~y occuring below a peat deposit. Amorphus peat - organic particles nearly or fully disintegrated. Fibrous Peat organic particles more-ordess intact. Bottom of Testhole includes last sample interval. Frost Line -- seasonal frost depth as described by drilling action and/or samples at the time of drilling. Frozen Ground - other than frost line, described by samples, usually includes description of ~ce content, often will include ~nodified Unified Classification for frozen soils this is a special case related to permafrost studies. Free Water Level -- The free water level noted dnringdrilling. This Is not necessarily the static water table at the time of drilling or at olher seasons. Static water table determination in other than very permeable soils requires observation wells or piezometer installations, used only m special cases. Blow/6'~' The number of blows of a 140 ~veight free falling 30" to advance a 2" split spoon 6": tile number of blows for a 12" advance is, by definition, the standard penetration. ,d% natural moisture content of the soil sample, usually not performed on clean sands or gravels below the water table. S~P, refers to 2" split spoon driven into the soil by 140 pound weight, a disturbed sample, ~, thin wall tube, "Shelby" used to obtain undisturbed samples of fine grained soil, .f,j., "grab" disturbed sample from auger flights or wall of trench, g, cut sample, undisturbed sample from wall of trench, Dry S[ten_kgt_~h -- a useful indicator of a soil's clayey fraction, N=Nonc, L-Low, M=Medium, H=High Group. - The samples are placed into apparently similar groups based on color and texture and are arbitrarily assigned a group letter. Furthm disturbed tests including Attcrberg Li~nits, grain size, moisture-density relationship, etc, may be perfornted on the group and are assumed to reflect the general distrubed characteristics of the soils assigned to the group. This is an important phase of the soil analysis and is used to standardize the various qualitative determilrations and to reduce the numher of quantitative tests necessary to describe the soil mass. SOIL CLASSIFICATION CHART 30o~ GRAVEl_ CLAY ,k r-~^vEv CLAYEY / "%,}~-',/~\ I o ~ '\/ ~-- -/-:-.--:;,,,: ........ oR /V,:- .,~x, / },:? /o I LT¥ / h SILTY //:'\,/ ',\/ ~ /~.?/6P, AVELLY SAND Sll_ ;)LAYEY R TY SANDY GRAVEL \ CLAYEY SILTY GRAVEL SAND GRAVELLY SAND SANDY GRAVEL GRAVEL / 0 10 20 30 40 50 60 70 80 90 ] O0 GRAVEL (+:~'4 SCREEN) % BY WEIGHT NONFROSTSUSCEPTIBLE SOILS ARE INORGANIC SOILS CONTAINING LESS TIIAN 3% FINER THAN 0.02 mm. GROUPS, OF I':ROST-SUSCEPTIBLE SOILS: F1 GRAVELLY SOILS CONTAINING BE'FWEEN 3 AN[} 20% FINER TIIAN 0.02 mm. F2 SANDY SOILSCON-IAINING BETWEEN 3 AND 15% FINER THAN 0,02 mm. F3 a. GRAVELLY SOILS CONTAINING MORE THAN 20% FINER -I-IIAN 0.02 mm. AND SANDY SOILS , (EXCEPT I:INESILTY, SANDS) CON]AINING MORE THAN 15% FINER THAN 0,02 mm. b. CLAYSWITI4 PLASIICI]Y INDEXES OF MORETItAN 12. EXCEPT VARVEDCLAYS. F4 a. ALLSILI'S INCLU[}ING SANDY SILTS. b. FINE SILTY SANDS CONTAINING MORETtlAN 15% FINER TIfAN 0.02 mm. c. LEAN CLAYS WITId PLASTICITY INDE'XES OF LESS -I ~IAN 12. d. VARVI_-D CLAYS. ·