HomeMy WebLinkAboutOUR MOUNTAIN S-4226BlocK. Municipality of Anchorag~ Planning Depar~t~nt 630 West 5th Ave. Anchorage., ~LasP~ 99501 Attn: Anchorage Platting Authority ., LI~%f~ ENGLRrEERING CO. 4839 T~Npa Circle Anchorage, Alaska 99504 August 7th, 1976 /_ Subject: Soils Evaluation and related Items - Our MDuntain Subdivision, A r~subdivision of Tracts 5A & 5B, ~%aley Subdivision, 5th Addition and Tracts 2, 3, & 4, Wba]ey S~x~ivision, 3rd Add'n. ~he following information concerning the soils conditions for the proposed Our ~ountain Subdivision located near Peter's Creek in ~ugi~k, is sub- mitred b) satisfy ~unicipal and State requiremsnts. Test Hole log~, soils analyses and project location maps follow the text. Site Location and Description: ~he approximately 43.8 acre parcel of land to be subdivided is located th~ee-fo~ of a mile east of the Glenn Highway near Peter's Creek~in Chugiak, just east of Ski Road. The property is overgrown with small birch on the areas previously ctear~d fmr homesteading and larger birch, spr%,~e, alders and cotonwood in m~st other areas. The topography is varied due to glacial and ri~r del~sits, but is g~nerally sloping to the Eest, toward the inlet. There are no adverse ~r~des on the roads, but the building lots to the so~ and east of the Edward Circle Cul-de-sac are such that will require steep driveways. Ex[sting Wells and Subsurface Drain Fields: ~he location of existing W~_lls or subsurface d~sposal areas near. this parcel are shown on the project location map. Ample water has been located in this .area with wells from 50 to 170 ft. Neighboring subdivisions (not shown on the map) have wells of sufficient capacity tm supply a small cun~nity. existance of a reliable water sour~.~ in this geologic~l ~u.~a t~s been pro~.=n sufficiently to sanitation officials in the /m~diate .past, Previous d~J~ical and bacteriological ~s~4ng of existing water sources has indicated that drin~ng water ~ality standards are satisfie~. All of the subst~rface disposal fields Jn tl~e irm~=diate vicinity have functioned satisfactorily in t]~e kind of s~il typical to this proposed subdivision. The subdivision agreement will contain provision for (md~ owner to s%bn~t a log of any planed wells ~ they are drilled, to the municipal] Field E~ploraticn: From July 20th to July 23rd, 1976, 33 test holes were excavated within tb4~ st~Ddivision at locations,selected by the geologist and emgineer. All holes were dug with a 3/4 yd Drott backhoe owned and operated by Klondike Com~tru~on Co. A graduate Geologist logged each of the test holes and. ~llected sample~ for further analysis° Each of the test holes were located as close as ~,ssible to potential disposal sites, noting property boundaries and to~graphical features. There is ~o~ t~nn sufficient room on the subject tracts -to locate water and waste water facilities m%d provied for ~.~place~a~nt disposal sites. M~icipality of A ~orag~ ~2t 7th, 1976 Geology: %he (hugiak area is located within t2~e Lower Matanuska I~wiand, a part of the Cook Inlet Lowland physiosra~ic subprovince that borders Oook Inlet. Five major Pleisto.cine glacial advances along the oonsequent or subsecp~nt lacustocine and alluvial deposits greatly influenced the prese~fc topography of the ar~a. ~he surfici~t geologic t=hit of the site appears to be part of the Peter's Creek Pan as it worked through the late Pleistocine lateral mora3~e ~posits. The till of this deposit is corm~nly sandy and stoney, with cobbles and boulders c~mcn. Pebbles and sand predominate but silt: and rock dust are present to provide a binder for so~-e soils. Cobbles and boulders are qenerally ro%nded rather than angular. Subsurface (bnditions: ~ne ground cover over the site g~nerally consists o'~ from 6 inches to a foot of organic silt filled with roots. Cou~e sands and gravels underlay the surface to a depth of 10 to 12 feet. This layer is interspersed with cobbles and sores boulders. A thin org-=nic layer (3 in. ) was found at a depth of 4 or 5 .feet in m~ny test holes. The entir~ area is underlain with well graded gravel occationally laced ~ith silt and sand layers. No ground water was encountered in any of the holes except a damp seepag~ f;-on-~ one of these sand layers. Below 12 feet, more densly packed sand and gravel deposits were encountered but still predominately well gra___~e~ and occationaly silty. One test hole that had kigher silt-sand contant was ~ched(ed with a percolation test to ob~3in .an actusl value for the soil in ¢~esticn. The results of all investigations showed that even the ~rest soils will support underground wast~ water disposal facilities. All ha%dng ~x~rer soils were made larger than an acre and a quarter in order to have sufficient room for future replacemsnt systems should such ever be required. The soil profiles show that the entire subdivision area is sited o~ g~Dd gr~%~, optimum for seepage pits. Tne soils were rated according to the Unified Soils Classification System, and wer~ temper~ by the results of the m~chanical analysis, the experience of the geologist and his observations. Where dual soils classifications are shown, it is due to the. instructions ].isted in the Unified Soils classification System but in all cases a soils rating is given, based on the analyses conducted and the observations made. ~hese ratings should be used for the design of the s~osurface disposal facilities by futur~ property owners. Conclusion: The soils underly~%g this proposed subdivision will support subsurfac~ disposal systems Which are properly designed and sized. There is sufficient l~mm on each of the proposed lots for a~ten~ate disposal areas. ~he soils a~.~uitable with respect to foundation bearing capacity for residential structures. The soils are generally NFS with layers of F-l, F-2, and F-3 Soil~. S oils t~sts were run in the right-of-way for .the preposed roads and all roads will be designed and constructed to meet current municipal road construction z~~ts for the soils encount~ Please contact ~ undersigned or clarifications of these data is neoessary. ~ I I 7P £ Uk ems 1 ~ ~ ,, J O' ~ 6.,? T~o Lees i ,Sr.,ALE,. i '-:-%' I 'SHEET a O~ ~ 4~3q TA/~P.~ C~RCL. E. 44~L zt_, 475a_ lo I% · b~uo~n sh ] [ - 4,~3q TA~IoA C~gc. kE. ,,.qe-gLr... '- I '$1-tEE'I" .-~- 0t: 41~x~ 4/} F~ glffaLI) i~OA~N6 LOC, S j I 4~3 q 'TAr~PA I~ORIN & ~/ALL, A CF-. I &C,RL~ -' ! 'SI-IF. ET ~ Off- -"- 485q TAmPR C,RCLE:. ANr. NOR,qG.F- iP t~ ~/~/~ ~4 S~ ~'LO ) i ~ALLACE EN~IN[ER~N~ 4~3q "TA~PR C~RCL£, A~Ct~O~E ~P :137.,.5c,. 1'~']'5'P~" 0,5 'Z,I -71 o5i_ TP t~ 'Z e2-1 ANC. HOI:~GE,, AbA.$KA I ~P ~i/ALLAC~ ? 'Z.I 'r I:IF.I.,B B.0R~N& LO&S I SC. ALE, -:' I 'SFIEET ~-',_ .., 04: -. ~:. 483q -rA/~pA C~¢LE. I- 0 0 000 ~o000 O o ooo 00'60 J ¥,/ALLACF-.. EN6~IINEEJ~;NC.,- 4a3q 'l'Ai'~Ph CIP,¢I,.E. ANCI.tO~,A~-~ '-FF' z4 'SHEET $,5' -Iec e-.o~bLc.s ¢ bc~.c-~p~3 -h~.m ¥,/ALLACF.. F--~61N~E~N(~ 4E~3q 'TAMP& ORCL. E. ~&ICHORA~E YP '~o 3,5 o©o o 4~3q 'TAMP& C~RCL. E. ,eedCl4OR,qG.F_.. FIELD I~OP, ING LO~$ J J ¥4ALLAC~ ? 463q TAMPA C~R,¢LE:, ~. s-L 5 FIELD I &tALE. , - -: -11 lo 483q "I'A~PA, C~RCD~L ANCFtORA~ CASE NU4$ER S-4226 Rezoninq PETITIOH FOR ~ . -_ , r,r ur Our Mo'untain Subdi..xzon bp(2C1 v Date Received Comment to I'/afl;~FJrJ. lW /,'~ ,-" ]~ For ff~e~[inq f ,' I .' ~ ~ ,( ~ .."' / CG, u_hTS. Cases ENVIRONMENTAL SANZ~A~''' ' PUBI, IC WATEP, NO[. AVAILABLE , ]~ON ~ ]?UB~,iC o-,, , -NG[P. AVAILABLE TO SERVICE PEII~IeN AREA. -.- ~ .....~ ........ ,;z~:;- :::__~Z~ " / / . / DT~00~225 PLA T APPROVAL NOTA R Y ACKNOWLEDGC:MENT ACCEPTANCE OF DEDICATION ~UG 2 9 ~980 RECEIVED DTI-00'!226 PL~.T OF TRACT 3 *_O¥~O~r.l OUR MOUNTAIN SUBDIVISION Resubdivision of Lots 5.6,7,6,gD,11. BIK1 OUR MOUNTAIN SUBDIVISION Located w~thm GRID:NWl361 1980-47( 9 7 PAPK SUBD. SLIt?YE~DP5 CE,PT-/FICPTE : C£/TTIKIC,4T£ 0£ OW/~£P~HIP (' DEDICAT?ON: LUCA5 SUPV£YIH& CO.