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Home My WebLink AboutPermit Field Test & Inspection Report 1994-9-6 1r"''''1II1Ii ..,.....r.,....,." f ',~. ;...-). September 6, 1994 , - J'\ ,ro ~-~'~/'7- "~" ~ I , ~\N\Q\(~ '~~15\f~K ~C\f\~~i8llL pr<<Jee-T BUILDING DESIGN,. FIRE PROTECTION CODE CONSULTANT", PLAN CHECKING CONSTRUCTION INSPECTION \VSTRUC'(j ~ \\G~<a 9j~~/(\ 0'1t. -fr<;y 8. 1~~to. <::,.0 ,.<::- '/1...(: uOB"\\ 'II? IV. 0 '$ ,oROTEG\\O k EXP6RES: 12-31:.J>'-1 Lot 1. Block. 3, N. E. Corner S ...!L.,...h9th PI. & Casca e r. Sprinafield. OR - Site/Soils Investiaation - w.O. #7721-ECM .. ..-.. -.,., ". . , '., r MORTIER ENGINEERING, P.C. P,O. BOX 139 . 1245 PEARL STREET EUGENE. OREGON 97440 PHONE (503) 484.9080 . fAX (503) 484.6859 . ~ ~D~~.~ Roger F. Johnson P.o. Box 3053 Eugene, OR 97403 f;i~~ORT CONSISTING OF GA TE X Y. , PAGES. THE BELOW SIGNED PARTIES HEREBY ACKNOWLEDGE RECEIPT AND APPROVAL OF THE RE: As you requested, on August 31, 1994 I witnessed the excavation of trenches by Emerald Excavating on this site in order to observe the si te surface and subsurface soil conditions. You had previously advised me with regard to your involvement with this site since 1990 when you purchased it. I received information from you with regard to previous grading and fill perfor.med on this site. The site is re~resented on the attached sketch from Bob Taylor of the the city of Springfield and the partial drawing of the subdivision plat map attached. The location of .the trenches is indicated on the attached sketch. Based on the information received, my observation of the site surface conditions and the trenches during excavation, I make the following report and findings: (The attached "Building. Report statement of Conditions and Limitations" is a part of this report). 1. si t.e Description: This is an approximately 120 ft. by 66 ft. lot adjoining the improved streets. The ground surface has a downward slope from southeast to northwest. There is a'steep sloped bank along the north property line with the lowest point being at the northeast. The maximum height of this slope appears to be approximately 7 to 8 ft. although I do not have specific topographic information. The ground surface contains cut weed or grasses and one fir tree located towards the northwest. 2. .Geoloaical Information: The geological information on this si te available through the Lane County Soil Conservation Service mapping indicates a silty clay soil mixed with displaced rock. I have observed many sites in this geographic and immediate ,area and concur in this finding. This type of soil is an expansive clay and requires special foundation design based on the Oregon State Building Code in order to preclude differential settlement due to the expansive characteristic of the soil. This is not uncommon in the Eugene/Springfield area. The most common practice in preparing this soil for foundation placement is to, install a gravel mat under the entire building atea. Mortier Engineering has developed a procedure used for the past 18 I ~ .- t~.., ,y-----. -. ... II. , ~ ~,;.." , ,i5.i\ '"''0_''':''''' 2 ;- years. A copy of the procedure is attached. This gravel mat is not considered an additional construction cost and provides for a uniform free'draining base for the placement of the conventional foundation. It is my understanding that 'the proposed construction on this site, is a convent"ional wood and timber framed one or two story residence supported on conventional. concrete footings and foundations vlith the normal accessory construction and site improvements similar to the adjacent sites. 3. Trench Excavation Lao: 'rhe trenches were excavated .with a 24 in. wide backhoe bucket on a Ford trac~or. Trencheswere excavated to a maximum depth of 6 ft. towards the north end tapering to at least 3 ft. at the south. Trench #1 at the west log as follows: l3 ft. south of the north property line, excavation to 6 ft. 0 to 40 in., river round rock gravel fill to 8 in. ,diameter. Some large angular. rock up to 18 to 24 in. This fill was loose. 42 in. to 60 in. . soil mixed with large angular rock to an, original soil depth at approximat~ly 60 in. At this location there is a stratum of what was original surface soLl. with approximately 6 in. of organic loam. At 72 in. the original soil was encountered. This trench tapered upward in depth to 36 in. at 30 ft. from the north property line with the round rock gravel fill extending to a depth of 12 in. at 30 ft. The depth ~as- 24 in. at 25ft. and 30 to' 36 in. at 20 ft. from the north property line. Similar conditions were encouniered below the round rock gravel fill as indicat'ed on the north end of the trench. The large angul~r rock decreased in siie and the depth ot fill decreased on almbsta straight line contour. . At the south end of this trench the stable soil was encountered at 30t,0 36 in. below the ground surface. . Trench #2 indicated in profile a similar fill condition with the round rock gravel being approximately 3 ft. in depth at 15 ft. from the north property line t06 in. in depth at 30 ft. from the north property line. The large angular rock mixed with soil ranged up to 4 ft. in maximum dimension ~ This is also fill material. The fill is underlain by 6 to, 12 i~ of organlc loam with the original stable soil 'encountered at a depth of 5 ft. at the north end of the trench to 26 in. at a distance 30 ft. from the north property line on a tapered stra'ight line. The original soil encountered below the fill and the organic original soil surface is angular rocks mixed vlith a silty clay soil, which is ,typical of this geographic area.. 4. Proposed Foundation Desian & Construction: In the area' of the proposed building, the excavation must be through the fill material and the original layer of organic loam: This would .mean . a maximum excavation' at a distance of 15 to 20 ft. from the north property line of 5 ft. from the existing ground surface and at a distance ~f 30 to 35, ft. from the north ,.'t"operty line excavatio'n to a depth of 24 to 30 in. ~ , \~: - t'~~-.Jf e,;\ ....".." , 8-' , ),) "',. >"...~ I , .L-,.~., ~ 3 E~cavations of more than 24 In. would be considered addit~onal, based on a unifor~ soil contour without any fill' materlal; therefore, excavatlons below this depth would ,be considered additional cost for.constructiori., However, sirice' the soil is. of an expansive type and the normal construction is with a 12 ih., U:ick gravel matt wi:thin the building area; therefore, excavat3.on to 30 or 36 In. ,below grade is not unqsual ,to accommodate t.hedepth of ttre ,gravel matt. The method df, construction' thereforei would be to excavate the building area toa minimum depth of 30 in. beiow'the present ground surface where there is no fill, IDp,terial. and 12 in. below' the o~iginal ground surface where the fill occurs and to fill with compacted gravei to a bottom of footing elevation and to install convent,ional foundations for the proposed building. 'The allowable 'soil bearing pressure on the compacted gravel fill would be 3.500 psf. This is at least equal to the normal foundation design, 'based on the Oregon state Building Code ~ I. do not consider this method of construction to be unusual in this geographic area nor in .most of the Eugene/Springfield area vlhere this type of soil exists .and th~ 'original ground surface has the c6ntour indicated in my observations. ~.is mv opinion that the fil.1 on this' site has enhanced its hlJ i 1 drlhl p (')lli1ractelliliQ2~--"~"----Th'e-'-addI-tIonaT-- excavated material can be disposed of on the site. The large rocks encountered in th~ excavation ,can be placed along the nort~ steep sloped bank for retention purposes . The building'c,an be placed at a suitable elevation' with regard to the existing street curb elevations.' This site is comparable to the adjoining sites and sites in the immediate neighborhood' which have had recent construction. 'A prospective buver should not be reluctant to.....I2il~..<;.l}Cl?e this_ si t~'7 .ba_e.~c.l.__Q!l._th~ . ~. or site conditions, Hy estimate of the additional.' cost. toexcava.te through the fill material. for' the placement of the gravel matt, which in-my opini6nis the only'additional cost, comD~..re:g' t~ l€vel site without fill is $3; ObO,. It should also be ~ecognized that if the fill were not placed on the site that the qround' contour would' result in placement of foundations ~t the same depth or height with regard to the floor elevations of. the proposed building. This is not an unusual site nor should other unusual costs be anticip9-ted in the . cO.flst.ructi~n . of the conventional residence comparable ~o the recent development. in the area. I hope you find this rep6rt adequate for' your purposes at this tirne~ Please cohtact me if you have further questions. Thank you for this opportunity to be of service. . Very truly yours, .E~ile Mortier, P.E. '\, ECM/rc Enclbsur~: Gravel fill procedure Drawing f) cf) -- - '7.~ ^-HII3/l " U MORTIER ~NGINEERINGf P.c. P.O. BOX 139 . 1245 PEARL STREET EUGENE, OREGON 97440 PHONE L50~ 4B4.';1080 . FAX (503) 484.6859 800-].5I:l-lW]4 OR STRUCTURAL BUILDING DESIGN e FIRE PROTECllO' CODE CONSULTANT 0 PLAN CHECKJN; CONSTRUCTION INSPECllON . BUILDING ANALYSIS Slalemenl of Condilions REPORT and Limilalions CUE:/iT: Roger F. Johnson W.O. I 7721-ECH lOCATION or PROPf:RTY LIB 1 k 3 ot , oc ,N.E. <;;orner S.L 69th Pl. & Cascade Dr. I. Type 01 Inspedion and ilems inspedcd is limiled 10: II. Slruclural Condilions b. Wealherproofing (exlerior surfaces) c. Slonn Drainage (Building. Sile) d. -X- Sile Conditions (Soils. Geological) e. Plumbing (fix lures, Piping) I. Healing (furnace. Ileal Pump, Air Condilioning. fireplace. Sloves. Chimneys) g. Eleclrical (Smice. Wiring, Oullels Chimneys) . h. Other . The inspedion is (or lhe purpose 01 alerling lhe c1ienl to major dcliciencies in the CQndilion. of the property described above and according to the condilio conlained in the report and lhis slalemenl. The inspeclion and report are perfonned and prepared lor the sole. confidential and exclusive use llnd possessi, o( the CUENT. No obligalion or responsibility 10 olher parlies is assumed. . This inspedion is 01 lhe readily accessible areas of the building and is limiled 10 visual observalions o( apparenl CQndilions exisling al the time 01 II inspection. ~tent and concealed delects and deficiencies are excluded Irom lhe inspection; equipment. conslruction and syslems "ill nol be dismanllcd. Mainlenance and olher items may be discussed. bullhey are nol a port o( our inspeclion. The report is nol a compliance inspection or cerWicalion (or pa orprcsent government codes or regula lions of any kind. The inspection cnd report do nol cddreS3 cnd are not intended to cddress the possible presence of or danger [rom any polenlially harmful subslances on environmenlal haurds including bul nol limiled to radon gas, lead pain!. asbestos. urea fonnaldehyde and loxic' or flammable chemicals. Any reference made lo lhese subslances in our report is made [or lhe sole purpose 01 alerting our clienl to lhe possibilily 01 lheir existence. Ie are making no posiliv delenninations as to their celual presence. as lie do not do laboratory tesling. II CUENT wishes any further in(onnalion or recommendalions in regard to lh presence 01 lhese substances. lie recommend contacling a specialized environmenlal conlractor. The report describes the property condilion and slatus on the date 01 inspedion. The purpose is to alert clients 10 presenl defects. Sub-surface soi conditions. inaccessible areas IInd features. appliances. security alarms. inlercom s)'Slems. solar heolin, s)"stcms or panels. sprinkler S)'Slems. spos. pools walcr solleners. cenl~l vacuum systems. and the presence or absence 01 rodents. lermites or other il1S(Cls cre ~eci{jClllll exdud<<l Irom .~~ ~pe 01 (hi- report. While every reasonable eflor! was made to delennine the property condition. no guarantees are expressed or implied. Ho resp<lflSlbdlty IS assumcc lor any ilems outside lhe scope of this inspection. nor can !fe be held responsible lor !fork perlonned by olhers. Uabilily (or dam~ge ~rising o~t. of errors 01 omissions shall be limited 10 lhe cost 01 the scope 01 inspeclion. No representations are made concerning the architeclural or englOeenng condlLJons. Mo~i.er ~ngin~enng. ils employee~ and agenls. assume no liability or responsibility lor t~e cosl of repairi.ng. 0: replacing' cny unreporl.ed dcf.ectsa:~ defICienCies. eIther currenl or arISing In the lulure. or for any properly damages. consequenllal damage or bodIly Injury 01 any nature: . The lOspe:llOn I d reporl are nol inlended or 10 be used as a guaranlee or Iforranly. expressed or implied. regarding [he cdcqu~cy. perfonnance or ~ndlllOn of any Inspec e slrtidure. item or system. for llORTIERE,HG1Htr~'~NG.,P.C., ' ""'-"./ ~', .)z . - .. _ ,". _ ,"." ~ . ctf,lJ' ""'\ . '_. . ~ '. . ....p;. ,,' .~ct:,~,._ ':: :. , , p.I:''' , "nt 'J" 0/1'../0/. valC --.:..:..::.-..~ ? 'i~__.._ .. / ?: 33/ I 3"AC I 13"CR j _. ....1 , , I \- j /3~~,.__J~ '\ \ q I 0 f-./~ ~Lt' . ' C tfiv(1~. :1V I 'x) "# I, l- ~ f1dP' / " I (;; ~ 1.~ l!f .z>2 ~,/ ~l L' I~"- -; -vI VJ '/ -,- -_. ~ ,'/ \9 --''',.-. ,..!.. . iJ '\ .. ... 'I . I CASCADE DRIVE {)JIOTH S 69TH _ S7CTH o/vv 50' - 36' s.-r: 3"AC. 16"CR C- D- S 50 1/46' RAD 321/36' RAD STREET PROJECT: SP-270. , '\\J 'f- ~' ~ I ,..,0 1/ f-~ ~.?\ ~ / I 00, (:::0 . - - --I SIDc?()J/tLk. ? ,t FAcE 0 F cu/28 ~ ~, 'I' -:rIL- I - - r $" C/;5C~oE VR. ..... l' r/k :. .;...~:., . '.' 1979 ~ - . ,~ " ~r vA--/1 &/1'1.-/ ~1 J