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HomeMy WebLinkAboutOVERLOOK ESTATES S-6954 & S-6954A ~UNICIPALITY OF ANCHORAGE Departmen~ of Health & Environmental _rotection Environmental Health Division Case Review Worksheet Case Number S-6954 Date Received March 31, 1983 Comments Due By April 20, 1983 Subdivision or Project Title: Overlook Estates Subdivision ( ) Public water available ( ) Community water available ( ) Public sewer available Comments: / January 20, 1977 R & M No. 652178 Paul Nangle Attorney at Law 705 West 6t3a Avenue Anchorage, Alaska 99501 .RE: Materials Site Investigation, Eagle .River, Alaska Dear ~. Nangle: In response to your request of November 12, 1976, for an evaluation of a potential materials source near Eagle River, a field investigation was begun on Nove.~Lber 18, 1976; Subseqllently, we have conducted laborato~], tests to identify the apparent grain-size distribution and natural moisture content of the on-site material. Three (3) copies of the Materials Site Investigation Report which includes our recommendations for the possible development of the materials site are enclosed. We are pleased t~ ~tave been given ~his opportunity to perfoz~ this investigation. Should you have any questions with regard to this report or if we can be of assistance to you in any way please contact us at your earliest convenience. Very truly yours, R & M CONSULTANTS, INC. Rooney ~/ ident PRELI~INARY MATERIALS SITE INVESTIGATION EAGLE Ri-v-ER, ALASKA p REPA3{ED FOR PAUL N~NGLE I. INTP, OQUCTION A prelhninary materials site investigation near Eagle River, Alaska, has been completed. ~ne site is located approxi~.atel/ 8~3 miles east of Eagle River along the north side of Eagle River Road, more specifically described as SE1/4 NE1/4, ~E1/4 S%~1/4 >~1/4, N1/2 ~1/4 SW1/4 ~E1/4, SE1/4 ~1/4 SW1/4 NE1/4, N1/2 SE1/4 SW1/4 ME1/4, SE1/4 SE1/4 SW1/4 NE!/4, and NE1/4 NE1/4 ~1/4 SE1/4 of Section 25, T14N, .R1W, Seward }~eridian, Alaska. The subsurface investigation was performed in accord~tce wi~ verbal inst_-uctions received from >~r. Paul N~ngle on November 12, 1976. On-site field exploration was initiated on November 18 and completed on December 1, 1976. it is our understanding that the site is being considered as a potential source of coarse-grained soil to be used as a construc=ion material. It is also understood that much of this material might be used for the reconstruction of the Eagle River Road and would nee~to meet specifications as set forth in the Alaska Standard Specifications for Highway Construction. The purpose of this report is to: 1). Descr~_b~e soil conditions as enco.~ntered during subsurface exploration. 2). Evaluate the data obtained from =~_~d exploration and laboratory testing programs. 3). Present our findings and recommendations regarding availability and suitability of the soil as a construction material. 3 II. SUBSURFACE INVESTIGATION The soil exploration and sampling operations were perfomned utilizing a track-mounted C~.~-45 rotary-type hydraulic drilling u_~it, a truck- mounted C~-55 rota~l-type hydraulic drilling unit, and a rubber-tired Drott 40 hydraulic backhoe. A total of two borings and four test pits were placed within the boundaries of ~he proposed development. Test hole and test pit locations are shown on ~he Location Diagram, Drawing A-OI. Test Pit 4 was advanced to a total depth of 18 feet below existing ground surface; Test Pit 3 and Test Hole 2 to 13 feet and ~ae remaining t.~ee holes ranged in depth from 15 ~o 16 feet. Drawings B-03 ~hrough B-05 present the complete logs of ~he tes~ holes and test pits. Test Hole 1 was advanced using a continuous flight 8-inch diameter hollow-st~ auger with representative material being obtained from the auger flights in the form of "grab" samples and by means of split-spoon sampling procedures modified from ASTM Specification D-1586-67. The modification in this latter procedure consisted of using a 2.5" I.D. split-spoon sampler driven with a 340-po~d drop hammer. For this procedure, a split-barrel sampler is driven into undisturbed natural soil with a drop-hammer having a 30-inch free fall. The penetration. resistance (as measured by blow count) gives an indication of t~e relative density of the in-place, unfrozen natural soil. Test Hole 2 was advanced using a continuous flight.6-inch diameter solid stem auger and Test Pits 1 through 4 were excavated with the bac'~hoe. Representative "grab" samples were obtained from each hole by the field geologist. After visual classification in the field, all soil samples were returned to the !~-boratory for further examination and testing. Iii. LA~O.RATOKY TESTI}~G ~T~e laboratory testing prcgr~ was limited to ~he evaluation of general soil index properties. Laboratory deter?,ination of the natural moist"-re content on representative s~.ples was perfor~,ed according to AS~.[ Specifica- tion D-2216-66. Particle size distribution a~aly$is was perform.,~ed on selected samples in accordance with AS~4 Specification D-422-63. The results of the laborato-~Y testing progr~ are - prided on Drawing C-01o IV. GENEraL SITE- DE$CRIPTIC~ For ~e purpose of topographic description, the site can be divided an eastern section ~%d a western section. The western section consists of a g!acio-fluvial fan wi~ boulders one to ~o feet in diameter occasion- ally dotting the surface. This fan is of Quaternary age ~nd is characterized by a broad sloping fan-like appearance. The eastern section of ~he site is ~o~ated on the lower slopes of a mountain and was inaccessable to exploration equipment because of its higk degree of inclination. A small stream approximates the boundary between ~he eastern a~d western sections. The vegetation consists primarily of birch, aspen, and spruce trees wi~h some cottonwood trees in the vicinity of the stream. Because of the site topography, the field investigation was limited to the western portion of the site. Therefore, all field descriptions, discussions and conclusions noted in this report generally apply only to that area. v. SUBSURFACE SOIL CONDITIONS The entire area is overlain by a silty organic mat approximately 0.2 feet t_hick. Beneath the organic mat, gravel to sandy gravel with varyin~ am,.ounts of silk predominated to ~he total dep~s explored. As much as 30% of the material in the gravelly layere consisted of cobbles and boulders as shown in the logs of Test Pits 2 ~d 4. Cobbles are defined as material between three and six inches ~n diameter with boulders beinq over six inches in diameter. No permafrost: was encountered during the field exploration and it is felt that ~%e possibility of encountering deep frozen material at this site is remote. vi. GROUNDWAT~.R CONDITIONS No water table was enco=ntered during the field exploration of the site and it is felt that perched water is unlikely in this area due to the permeable nature of the soil. However, the gravelly layers were observed to be wet in all of the test pits with the exception of Test Pit 2, and and locally, heavy precipitation could result in standing water in open excavations. VII. DISCUSSICM, CONCLUSIONS A~ KECO~t~I~ATICNS The ultimate disposition and intended use of ~he site material will be the primary factor governing the quantities of accept~)le material mined ~ at'chis locationl': In addi~ion,'t~he nature of the mining operations and the actual depositional character and composition of the deposits will quantitatively influence the available volumes of high quality material° Most of the soil on site contains boulders and cobbles which may re?~ire c~ashL~g before utilization (depending on governing specifications) may contain excessive am. ounts of fine grained material that could necessi- tate sieving and/or washing in order to satisfy quality requirements. These factors should be given consideration ~ the overall evaluation of the development of the ..materials source. in addition to oversize material restrictions, ~na frost susceptibility of the soil must be considered. For estLmating ?~rposes, soil can be considered acceptable for use as a non-frost susceptible (NFS) material if it has been less than 10% (by weight) passing a 5200 sieve. Soil with 10% to 20% (by weight) passing a ~200 sieve is marginally acceptable as an NFS construction fill and soil wi~h more ~d?_n 20% (by weight) passing on ~00 sieve is normally not acceptable as an NFS fill material. Of course, applicable specifications will govern final N~S criteria. Based upon our laboratory tests, most of the soil samples tested fell into the 0-10% range; however, r~ving oversize material could cause an ~nacceptable increase in the percentage by weight of soil passing a ~200 sieve. In addition, material which is only marginally acceptable in its natural state could be rendered unacceptable if oversize material is removed. Based upon the information gained from t-he t~o test hole and four test pit field exploration progr~.m, ~_nd t~he 1Ln, ited laboratory test da~a, it .... ~.~'~, / . ., . · ,,.. ,..~.~,,. ~,.~., --.,~,,.,,.,,~,~',, '~":~,.>,~r',..~,.,.,~,'~-~.=x.~-.~ ---.,,.. ~ -. · .. ..... ~',.i.-.,-._.9?. ....... · : · i "." r"'~"'~--""Jx'~/ .... 'r'~-d .....,..,..-:.~ ~.:~'.,.t,,.~ ~. ¥,/.~2..'~.,~., ..~.,?; -- ,~:..~--. ~ ·, .,-.,- .~ ~%pp.ears that the site. is.unsuitable .for development as a construction materials site without employing some me~ns of processing the materia~ before use. Any of four different materi~ls processing procedures could be employed at the site to modify the material to meet expected governing specifica- tions, for ex~,~ple, the Alaska Standard Specifications for Highway Construction as sho,~n in Appendix A. The four types of processing are: Crushing - This technique reduces t_he size of the large particles in the material by breaking them into smaller pieces. Screening - This technique can segregate material accordL~g to particle size. 3. Washing - This tecb_nique reduces the amount of fines in & material by washing them away with water. 4. Some comfoination of the above. The crushing process can produce products ~%at are in high demand such as concrete aggregate or roadway material. By utilizing a crushing process, the boulders and cobbles could be reduced to a desirable size. The crushing process, however, produces two products that can be enviror~entally undesirable: noise and dust. For ~his reason, a crushing plant should be located in an area where it will cause minimal disturbance to surrounding inhabitants. Before a crushing process could be ~plemented, additional lab testing should be undertaken to determine the so~dness of ~he material to be crushed~ In addition, noise suppression and dust disposal techniques should be analyzed. Screening c~n segregate material by particle size and the segregated material can possibly be sold as rip-rep, orn~.ental rock, filter rock, concrete a~gregate, depending upon its size. D~ screening can, however, create ~ ~desir~-ble dust source and may be e~viro~entelly ur. appealing. A washing process at this site might be advantageous if used in conjunction with ei~er a crushing or a screening process. By their nature, washing pl~ts re,dire a high vol~T,e of water to operate and because of environmental restraints, tko wash water cannot be discharged into a stream or lake without some m~er of filtration. Therefore, a settling pond should be incorporated to trap silt and clay sized particles if a washing plant is pla~ed. The available quantity of useable material available for processing at this site is roughly estimated to be 800,C00 cubic yards. Up to 30 percen~ of this material is oversize (boulders and cobbles) ~nd because of the highly variable silt content, all material must be classified as only marginally non-frost susceptable unless processed. The following assumptions were used in establishing ~is estimate: 1. Useable material extends only to ~ae ~epths investigated (it ..a .... al extends to depths of at is suspected that similar - least 20 fee~ throughout ~te %¢orkab!e portion of the site, quantity estimates are probably conservative). Only the western portion of the site is workak;le. (This does not imply that the eastern portion of ~he site ca~uuot be mined). 3. A buffer zone will remain along property lines and along the creek. 4. One or two acres of the site would be needed for waste storage and processing equipment. 5o NO waste area for storage of overburd~ will be required. The sides of the excavation will be r~intained on a one to one (1:1) slope. We reco~end that the following be considered if ~he site is to be developed as a materials source. long range plan should be developed which will allow ~he land to 'b~ fully utilized even after the salable materials have been removed. 2. A minimum buffer zone of 50 feet should be provided along the boundaries of the site and along the small stream that flows ~urough ~_he site. This provision will not only reduce ~he enviromme~tal Lmpact during the extraction period, but will also provide a favoraDle condition for future development. After the site.is excavate~ ta the depths explored, a further .......... subsurface investigation should be undertaken to determine the feasibility of continued mining~ Initial site planning and development should not preclude excavation to depths greater ~han those explored if acceptable material is found at greater dep~s. Due to the inclination of the site, a large excavation may require terracing to prevent slope failures and provide ease of mobility for extraction e~dipment. If the material is to be processed to elLmLnate ~he high percentage of cobbles, boulders and fines we feel ~kat a crushing operation (if termed feasible by additional lab tests and enviror~enta! factors) would be superior to a scieening operation. Crusher products are generally in greater defend ~an ~he specialized screenin9 products and therefore are usu=l!y r~re economically beneficial to produce. If a crushing operation is termed feasible, ~he crusher may produce more fines than acceptable to any governing specifications~ Therefore, some provision for washing the crushed material should be included in the processing operation. t '~P- I 7"b4 - / /! VIIIo CLOSURE ..... '~' ~ We appreciate being given the opportunity to perform this investigation. If you have any questions regarding the field inYestigation or this report, please contact us at you~ e~rliest convenience. Very truly yours, R & M CONSULTANTS, INC. Ed Yarma2<, Jr. Geotechnical Engineer EY/~.~./dap SOILS _..CL.ASS[FICATION, CONSISTENCY AND SYMBOLS.._: CLASSIFICATION: Ic~en~if~c'a~ibn and cla~{~ida'~ion o~ ~he s~ is acco~plished accord~ce wi~h ~he Unified So~ Clas~lca~{on System. Normally, the grain dis~bution de~e~m~es clas~ica~ion of the soil. ~ne ~oR is dabbled accortina major ~d m~or const{buen~sw{~h the m~or elements serves as modifiers major elements. For cohesive so~s, the clay becomes thepr~c{palnoun other maj~r~so~cons~{tuenbs use~ as mod{fler; {.e. s~ clay, when the clay are such ~hat ~he claydom~a~es so5 properties. M~or so2 constituents may added ~o ~he class~ica~{on 5reg~down ~n accordance w{~h the par~{cle size proportion listed below; i.e. sandy s~t w/some ~ravel, ~race clay. no c~ ~ 0 - 3~ trace - 3 - 12~ ~ome - 13 - 30~ SOIL CONSISTENCY - CRITERr. A: SoY consisteacy as de~L-~ed below a-~.d by normal ~i~ld and l~ora~o~ me~hods appl{es o~y ~o non-~rozen ma~er~!. For ~hese mater{~, the ~uance o~ ~uch fac:or~ a~ so~ s~c~e, i.e. sys~e~s~ s~a~e cra~s, s~<ens[des, e~c., mustbe t~en ~o cons{darat{oa ~ m~<~g ~y coz:re!at{on with ~he consistent' vaIuesEstedbe!ow. Inpe~afros~ Cohes{o~ess Cohas{ve N*~lows/ft) Relax-ira Loose 0 - 10 0 to 40~ b'Ied{um Dense 10 - 30 40 to 70~ Dense ~0 - 60 70 to 90~ Very Dense - 60 90 to 100~ *Standard Pene~ca~ion "N": Blow~ per foo~ of a 140-pou~d har~, met ~al/in~ 30 [.~oh-=s on a 2-inch OD spl{t-spoon excep~ where noted. DRILLING SY~..q30L $ T- (tsf) Very Sof~ 0 - 0.25 Sof~ 0.25 - 0.5 S~= 0.5 -1.0 . F{x-r~ 1.0 - 2.0 Very Fi~m 2.0 - 4.0 Hard - 4.0 WO: Wash Out WD: W]'.: Water Level BCR: WCI: Wet: Cave In ACK: DCI: Dry Cave In AB: WS: l~n kle Sampl;mg TD: Wh{Ie Dr LllLng' Before Cashng Removal After Cas{ng Removal AJ~er Boring Total Depth Note: Water levels {nd{.¢ated on the bo.~mg log~ are the levels re. easu~ed {m the borLng ak the t{raes {ndicated. In pervious unfrozen soils, the {nd{cared e!evakion$ are considered to represent actual ground water conditions. In ~ape~vious and frozen soils, accurate deterr~-[nations o~ ground water elevations cannot be obtaLued with{n a lJ.-nited period o~ observation a~ud other evidence on' ground \rater e!evat:ons and condi~"lons are requLred. ~C{~XO: G.L.B. ? I'.-~:, 3-1-72 M E'"rAMORPHIO RG~K ICE, h:ASSIVE ICE-SILT ORGANIC SILT SILT GRACING TO SAN0¥ SILT SA,*-'C~ GRAVEL, SCATT-ZREO CCBBLES (ROCK FRAGMENTS) INTE.~.-AYEREO SAND ~ $A~;OY GRAV~ SILT'T CLAY St ..... 1.4" SPLIT SPOON Ss ..... I.~." SPLIT SPOON SI ..... ~5" SPLIT SPOON Sh ..... 2.5" SPLIT SPOOM Sx ..... ?.O" SPLIT SPOON Sz ..... 1.4" SPLIT SPOON Sp ..... 2.5" SPLIT SPOON, Hs ..... 1.4" SPLIT SPOON S¢.MPLER TYPE SYMBOLS WITH 47~*~~ HAMMER VtlTH 140~ HAMME~ WITH I40~ HAMME8 WITH 3~ HAMMER WITH I~0~ H~MME~ WITH ~40~ HAMMER PUSHED DRIVEN WITH AIR HAM~4ER Ts .... SHELBY TUBE Tm .... MODIFIED SHELBY TUBE Pb .... PITCHER BARREL Cs .... CORE BARREL WITH SINGLE TUEE Cd .... CORE BARREL WITH DOUBLE TU~E 8s .... BULK SAMPLE A ..... AUGER SAMPLE G ..... GRAB SAMPLE HI ..... 2.5" SPLIT SPOON DRIVEN WITH AIR HAMMER NOTE: SAMPLER TYPES ARE EITHER NOTED ABOVE THE BORING LOG OR SAMPLE DEPTH. ADJACEHT TO IT AT T~..E RESPECTIVE GRAD4TIO, V4& TYP!CAL BO,=,IHG LOG Cons~ Visible Ic~ 0'-7' lC~ -SILT 90, 56.2% CHA / I G E , ~' I S~OY SI LT ~--eco;v~/Foor . SAI/PL~ ,VU,~IBE~ SANDY GRAVEL AgC~rlO>l 30' ' D~I4L D~P~H ~ ;ZD.-WHI&[ ORI&L,;'/g, A.B.--AF?ER BOR/MG F.?, ¢1 .~1: L.u.S. I C~, O: G.L.-% EXPLAHATION OF SELECTED SYMBOLS Ir.s. N/A G~iO: N/A Sh 11-19-76 Elev. 279.2 0.0' SA~IDY GRAVEL w/ SCALE SILT 1.0' SOt-~ ~ILT Occasional Boulders 3.0 G~'~I~Y S.~D w/ T~CE SILT ~-~ny Cobbles G~¥ZEL w/ SO:,~ SA2~ ~any Cobbles ~ ~ Some Boulders ""~ ~Dense TH 2 11-19-76 :Elev o 276.7 All Samples A - SA~Y GRAVEL w/ TP~%C~- TO SO:,~ SILT 0.0~ --.1.5 ' GRAVEL'#/ SO~.~ Many Cobbles Occasional Boulders De~se GRAV]~L Loose, Dry 8.5' Sh @ [.L~ny Cobbles Refusal on Largs Bo~lder Refusal on Large Bod'~.der!3'0' EY 12-3-76 LCG OF TEST HOLES PAUT~ N ~GLE /I,~O,.NO 65217~ : LOwG. NO. B-03 12-1-76 GRAVELLY S~D w/ $O~'~ SILT Occasional Cobbles and Boulders --3o0' SA~Y G.o~A%~L w/ TRACE S1-LT Hany Cobbles Occasional Boulders Dense, Wet 15.0' T.D. Refusal on Large Boulders TP 2 , Elev. 2y6~7 ,.12-1-76 i Ail. Samples A $A~Y GRAVEL w/ SO~.~ 25-30% Cobbles Occasional Boulders Brown, Loose SA~Y G.~A~L TO G~A~L ~/ Approxir~tely 30% Cobbles and Boulders, Loose 16.0' Refusal on Large Boulders LSC~L~: 1"=3' . . . LOG OF T~BT PITS PAUL ~GLE EAGLE P. IVER~ ALASKA ~3 12-1-76 TP 4 Elev~ 271.0 12-1-76 ' Ail:. S.a~mples A 0.0' S~IDY GP~VEL w/ SO~r~ SILT Many Cobbles Some Boulders ~-}, Loose, We~ / 6.0~ GRAVEL w/ SO:.~ SAZKD; TRACE TO SO[LE SILT f~ny Cobbles Some Boulders TRAC~.'~ TO SO~-~ SILT ApProximately 20% Cobbles Occasional Boulder ~Loose, Wet Large Boulders @ 12.0' Refusal on Bedrock or Large Boulder 13.0' T.D __ Approximately 30% Cobb!es~ and Boulders @ 10.0' SA,XYDy GRA.VEL w/ ~.~?~C~ SiLT Dense, Wet Approximately 25% Cobbles and Boulders 18.0" T.D~ 12-3-76 i"-3 ' - ,, 1 ~.NO. 652178 LOG OF TEST P~TS PAUL ~IANGLS: ~\GL~ R3TV~R, ALASKA January 20, 1977 R & M No. 652178 Paul Nangle Attorney at Law 705 West 6th Avenue Anchorage, Alaska 99501 RE: Materials Site Investigation, Eagle River, Alaska Dear Mr. Nangle: In response to your request of November 12, 1976, for an evaluation of a potential materials source near Eagle k~ver, a field investigation was begun on November 18, 1976. Subsequently, we have conducted laboratory tests to identify the apparent grain-size distribution and natural moisture content of the on-site material. Three (3) copies of the Materials Site Investigation Report which includes our recommendations for the possible development of the materials site are enclosed. We are pleased to have been given this opportunity to perform this investigation. Should you have any questions with regard to ~%is report or if we can be of assistance to you in any way, please contact us at your earliest convenience. Very truly yours, R & M CONSULTANTS, INC. JWR/ddp PRELIMINARY MATERIALS SITE INVESTIGATION EAGLE RIVER, ALASKA PREPARED FOR PAUL NANGLE I. INTRODUCTION A preliminary materials site investigation near Eagle River, Alaska, has been completed. The site is located approximately 8.3 miles east of Eagle River along the north side of Eagle River Road, more specifically described as SE1/4 NE1/4, NE1/4 SW1/4 NE1/4, N1/2 ~1/4 SW1/4 NE1~4, SE1/4 NWl/4 SW1/4 NE1/4, N1/2 SE1/4 SW1/4 ME1/4, SE1/4 SE1/4 SW1/4 NE1/4, and NE1/4 NE1/4 NE1/4 SE1/4 of Section 25, T14N, R1W, Seward Meridian, Alaska. The subsurface investigation was performed in accordance with verbal instructions received from Mr. Paul Nangle on November 12, 1976. On-site field exploration was initiated on Nove~ber 18 and completed on December 1, 1976. It is our understanding that the site is being considered as a potential source of coarse-grained soil to be used as a construction material. It is also understood that much of this material might be used for the reconstruction of the Eagle River Road and would need to meet specifications as set forth in the Alaska Standard Specifications for Highway Construction. The purpose of this report is to: 1). Describe soil conditions as encountered during subsurface exploration. 2). Evaluate the data obtained from field exploration and laboratory testing programs. 3). Present our findings and recommendations regarding availability and suitability of the soil as a construction material. II. SUBSUP~'ACE INVESTIGATION The soil exploration and sampling operations were performed utilizing a track-mounted C~-45 rotary-type hydraulic drilling unit, a truck- mounted C5~-55 rotary-type hydraulic drilling ~mit, and a rubber-tired Drott 40 hydraulic backhoe. A total of two borings and four test pits were placed within the boundaries of the proposed development. Test hole and test pit locations are shown on the Location Diagram, Drawing A-01. Test Pit 4 was advanced to a total depth of 18 feet below existing ground surface; Test Pit 3 and Test Hole 2 to 13 feet and the remaining tlLree holes r~nged in depth from 15 to 16 feet. Drawings B-03 through B-05 present the complete logs of the test holes and test pits. Test Hole 1 was advanced using a continuous flight 8-inch diameter hollow-stem auger with representative material being obtained from the auger flights in the form of "grab" samples and by means of split-spoon sampling procedures modified from ASTM Specification D-1586-67. The modification in this latter procedure consisted of using a 2.5" I.D. split-spoon sampler driven with a 340-pound drop hammer. For this procedure, a split-barrel sampler is driven into undisturbed natural soil with a drop-hammer having a 30-inch free fall. The penetration. resistance (as measured by blow count) gives an indication of the relative density of the in-place, unfrozen natural soil. Test Hole 2 was advanced using a continuous flight.6-inch di~neter solid stem auger and Test Pits 1 through 4 were excavated with the bac~dnoe. Representative "grab" sa]nples were obtained from each hole by the field geologist. After visual classification in the field, all soil samples were returned to the laboratory for further examination and testing. III. LABORATORY TESTING PROGRAS! The laboratory testing program was limited to the evaluation of general soil index properties. Laboratory determination of the natural moisture content on representative samples was performed according to AST~! Specifica- tion D-2216-66. Particle size distribution analysis was performed on selected samples in accordance with AST~! Specification D-422-63. The results of the laboratory testing program are provided on Drawing C-01. IV. GENERAL SITE DESCRIPTION For the purpose of topographic description, the site can be divided into an eastern section and & western section. The western section consists of a glacio-fluvial fan with boulders one to two feet in diameter occasion- ~lly dotting the surface. This fan is of Quaternary age and is characterized by a broad sloping fan-like appearance. The eastern section of the site is {o'cated on the lower slopes of a mountain and was inaccessable to the exploration equipment because of its high degree of inclination. A small stre~n/n approxk~ates the boundary between the eastern and western sections. The vegetation consists primarily of birch, aspen, and spruce trees with some cottonwood trees in the vicinity of the stream. at'~his locationl In ad~ition,~t~e nat~e of the mining operations and the actual depositional character and composition of the deposits will quantitatively influence the available vol~nes of high quality material. Most of the soil on site contains boulders and cobbles which ma~ require crushing before utilization (depending on governing specifications) and may contain excessive amounts of fine grained material that could necessi- tate sieving and/or washing in order to satisfy quality requirements. These factors should be given consideration in the overall evaluation of the development of the materials source. In addition to oversize material, restrictions, the frost susceptibility of the soil must be considered. For estimating purposes, soil can be considered acceptable for use as a non-frost susceptible (NFS) material if it has been less than 10% (by weight) passing a ~200 sieve. Soil with 10% to 20% (by weight) passing a ~200 sieve is marginally acceptable as an NFS construction fill and soil with more than 20% (by weight) passing on ~200 sieve is normally not acceptable as an NFS fill material. Of course, applicable specifications will govern final N~S criteria. Based upon our laboratory tests, most of the soil samples tested fell into the 0-10% range; however, removing oversize material could cause an unacceptable increase in the percentage by weight of soil passing a ~200 sieve. In addition, material which is only marginally acceptable in its natural state could be rendered unacceptable if oversize material is removed. Based upon the information gained from the t;~o test hole and four test pit field exploration program, and the limited laboratory test dasa, it ~ppears that the site.is~unsuitable for development as a construction materials site without employing some means of processing the material before use. Any of four different materiauls processing procedures could be employed at the site to modify the material to meet expected governing specifica- tions, for example, the Alaska Standard Specifications for Highway Construction as shownn in Appendix A. The four types of processing are: 1. Crushing - This technique reduces the size of the large particles in the material by breaking them into smaller pieces. Screening - This technique can segregate material according to particle size. Washing - This technique reduces the amount of fines in a material by washing them away with water. 4. Some combination of the above. The' crushing process can produce products that are in high demand such as concrete aggregate or roadway material. By utilizing a crushing process, the boulders and cobbles could be reduced to a desirable size. The crushing process, however, produces two products that can be enviror~entally undesirable: noise and dust. For this reason, a crushing plant should be located in an area where it will cause minimal distturbance to the surrounding inhabitants. Before a crushing process could be implemented, additional lab testing should be undertaken to determine the soundness of the material to be c~n/shed. In addition, noise suppression and dust disposal techniques should be analyzed. Screening can segregate material by particle size and the segregated material can possibly be sold as rip-rap, ornamental rock, filter rock, concrete aggregate, depending upon its size. Dry screening can, however, create an undesirable dust source and may be environmentally unappealing. A washing process at this site might be advantageous if used in conjunction with either a crushing or a screening process. By their nature, washing plants require a high volume of water to operate and because of environmental restraints, the wash water cannot be discharged into a strea~, or lake without some manner of filtration. Therefore, a settling pond should be incorporated to trap silt and clay sized particles if a washing plant is planned. The available qllantity of useable material available for processing at this site is roughly estimated to be 800,000 cubic yards. Up to 30 percent of this material is oversize (boulders and cobbles) and because of the highly variable silt content, all material must be classified as only marginally non--frost susceptable unless processed. The following assumptions were used in establishing this estimate: 1. Useable material extends only to the depths investigated (it is suspected that similar material extends to depths of at least 20 feet throughout the workab!a portion of ~he site, so ............. ~-~-~-~-~-~-~r~ .... ,.,~, .......... .,...~ ..... ...........-~ ....... . ........ ~.-?.~., .~ .......... ~... ~ quantity estimates are probably conservative). Only the western portion of the site is workable. (This does not imply that the eastern portion of the site cannot be mined). 3. A buffer zone will remain along property lines and along the creek. One or two acres of the site would be needed for waste storage and processing equipment. 5. No waste area for storage of overburden will be required. 6. The sides of the excavation will be maintained on a one to one (1:1) slope. We recommend that the following be considered if the site is to be developed as a materials source. A long range plan should be developed which will allow the land to b~ fully utilized even after the salable materials have been removed. 2. A minimum buffer zone of 50 feet should be provided along the boundaries of the site and along the small strewn that flows through the site. This provision will not only reduce the environmental impact during the extraction period, but will also ]provide a favorable condition for future development. ~ -':.'~r' .- r.-~f.~'x~/L, -.~.~,,%,%,,.e~;..~,~:~:,~;~,,~.,,~a.,,,. .... ,, ....... -, ~-...~o.,:,.. ..... ,.- ............. . ....... ,-..-.~ ...,, ~; After the site is excavated to the depths explored, a further ....... subsurface investigation should be undertaken to determine the feasibility of continued mining. Initial site planning and development should not preclude excavation to depths greater ~han those explored if acceptable material is found at greater depths. Due to the inclination of the site, a large excavation may require terracing to prevent slope failures and provide ease of mobility for extraction equipment. 5o If the material is to be processed to eliminate the high percentage of cobbles, boulders and fines we feel that a crushing operation (if termed feasible by additional 1~) tests and environmental factors) would be superior to a screening operation. Crusher products are generally in greater demand than the specialized screening products and therefore are usu~_lly more economically beneficial to produce. If a crushing operation is termed feasible, the crusher may produce more fines than acceptable to any governing specifications. Therefore, some provision for washing the crushed material should be included in the processing operation. VIII. CLOSURE We appreciate being given the opportunity to perfozm ~is investigation. If you have any questions regarding the field investigation or this report, please contact us at youz earliest convenience. Very truly yours, R & M CONSULTANTS, INC. Ed Yarmak, Jr. Geotechnical Engineer EY/~R/ddp "-L.- I./ 4 SOILS __,.CI.~ASS[FICATION, CONSISTENCY AND SYMBOLS_ ..; " CLASSIFICATION: Iden%iflc'a%{6n and cla~'s{fidat{on o~ the s~i~ {s accomplished in accord~cewlth the Uni~{ed So~ Class~lcat{on System. Normally, the gra~ disk.but{on determ~es classY{cation of the soil. ~ae meg is defied accord{nE to major ~d m~or constituents with the m~or elements serv~g as mod{fiefs o~ the major elements. For cohesive soils, the clay becomes thepr~cipalnounw{th the other major',soHconst{tuentsused as modifier; i.e. sH~clay, when the clayp~icl~s are such that the claydom~atessohproperties. Mh~or so~ const{tuents~ay added to the class~lcat{on breakdown ~ accord~ce wl~h the particle size properS{on listed below; i.e. sandy s~t w/some gravel, trace clay. : no c~ ~ 0 - 3~ trace - 3 - 12% some - 13 - 30~ SOIL CONSISTENCY - CRITERIA: Soil consistency as defined below and deterr~,L-.ed by normal field and laborato-~y methods applies only to non-~rozen mater~I. For these mater{als, the influence of such facto~:s as so{1 structure, i.e. 'fissure systems, shrinkage, cracks, sllckensides, etc., must be taken into cons{derek{on ' in making any correlation with the cons;.stency values listed below. In permafrost zones, ~he consistency and strength o~= frozen so{ls may var), s{~nificantly and unexplalnably with ice content, thermal regi~ne and so{1 typ~. Cohes{onless Cohesive T- (tsf) N*¢lows/ft) Relative Density Loose 0 - 10 0 to 40% Very Soft: 0 - 0.25 Medium Dense 10- 30 40 to 70~ Soft 0.25'- 0.5 Dense 30- 60 70 to 90~o St{f-~ 0.5 - 1.0 . Very Dense - 60 90 to 100~ Firn% I. 0 - 2.0 *Standard Penetration "N": Blows per foot of Very FLrm 2.0 - 4.0 a 140-pound hammer falling 30 inches on a Hard - 4.0 2-{nch OD split-spoon except where noted. DRILLING S~f MB eLS we: Wash Out WD: WL: Water Level BCR: WCI: Wet Cave In ACR: DCI: Dry Cave In AB: WS: V~£le Samplin~ TD: While Drilling' Before Casing Removal After Casing Removal After Boring Total Depth Note: Water levels indicated on the boring logs are the levels measured [n t]-~e boring at the times karl{caked. In pervious unfrozen soils, the indicated elevations are considered to represent actual ground water conditions. In impervious and frozen so{Is, accurate deterrnina~ions of ground water elevations cannot be obtaLned withLn a lk-nited period o~ observation and other evidence on gte%tad water elevations and conditions are required. CWN: LmD.S. GE. NERAL Lov,,,q. NO. B-OI gxO: G.L.B. OCTE: 3-1-72 GENERAL NOTES STANDARO GYM OOLS oOO GRAVEL LIMESTONE IGNEOUS POCK ~ M ~TAMORPHIC ROCK ICE~ MASSIVE ICE-SILT ORGANIC SILT ~hOY SILT SILT GRADING TO SANDY SILT SANDY GRAVEL, SCATTERED COBBLES (ROCK FRAGMENTS) IN TE.="--AY ER ED SAND ~ SAC;DY GRAVEL SILTY CLAY St ..... 1.4" Ss ..... 1.4" SI ..... ~5" Sh ..... 2.5" Sx ..... 2-_0" Sz ..... 1.4" Sp ..... 2.5" Hs ..... 1,4" SAMPLER TYPE SYMBOLS SPLIT SPOON WITH 4?# HAMMER SPLIT SPOON WITH 140# HAMMER SPLIT SPOON WITH 140# HAMMER SPLIT SPOON WITH 340# HAMMER SPLIT SPOON WITH 140~t~ HAMMER SPLIT SPOON WITH 340# HAMMER SPLIT SPOON, PUSHED SPLIT SPOON DRIVEN WITH AIR HAMMER Ts .... SHELBY TUBE Tm .... MODIFIED SHELBT TUBE Pb .... PITCHER BARREL Cs .... CORE BARREL WITH SINGLE TIJRE Cd .... (;ORE BARREL WITH DOUBLE TUBE Bs .... BULK SAMPLE A ..... AUGER SAMPLE G ..... GRAB SAMPLE HI ..... 2.5" SPLIT SPOON DRIVEN WITH AIR HAMMER NOTE: SAMPLER TYPES ARE EITHER NOTEO ABOVE THE BORING LOG OR ADJACENT TO IT AT TH,,E RES~'~¢TIVE SAMPLE DEPTH. TYPICAL BORING LOG BORliVG A!UI'48ER-...,.T. H. 30- 15 DAT~ DRILL~O--~iO. 21- 70 SAMPLEFF TYPE%ss FtA TS/? Gr?ADATIO, VAL FI?OZ£N S5 Cd Elev. 274.6 ....-ELEFAT/O,V ~iV FEET' All S~mples Ss''''''''S~/''I?LE/? TYPE 0' ORGANIC MAT~RIA L I' Consi~ Visible Ice 0'-7' ICE+ML ICE. SILT SANDY SI LT LiHle toNoVisible Ice 13'-~' Vx ~ICE, D~SC~IPTIO/V ~ =?lO/ 859~'f 28° GP (CO~PS OF ~ ~ %. ~ U~/I~'ED OR FAA X ~'~rEn CC, VT~7/T SANDY GRAVEL 95 SCHIST ~OS, VEP~L/ZSD SO/~ O~ LOC~r/~H ~0' ~ ~YO.-WHILE Dt?ILL/,VE, A.~-AFT£R f 3 W .N: L,.u.S. [CKD: G.L.B. [C,£,TU: FE~. 1972 l::l&i'V1 C::r"D.~,~I. JLTANT~, IN~--_,I. EXPLA HATION OF S~LECTED SYMBOLS N/A N/A GENERAL Sh Sh TH 1 11-19-76 Elev. 279.2 SAMDY GRAVEL w/ SOME SILT , 0.0' _1.0' GRAVELLY SA~ w/ SO~-~ SILT Occasional Boulders 3.0I GRAVELLY SAND w/ TRACE SILT t.~ny Cobbles 34 5.5~ GRAVEl, w/ SO~ SAND Many Cobbles Some Boulders Dense Q 36 TH 2 11-19-76 Elev. 276.7 All Samples S~DY GRAVEL w/ TRACE TO SO?~ SILT --.1.5' GRAVEL w/ SO~ S~4qD Many Cobbles Occasional Boulders Dense GRAVEL Loose, Dry --8.5' 13.0' Refusal on Large Boulder Sh ~ 15.0' ---~f-w~ ~-o~ S~D ~.~ny Cobbles 16.0' T,D, Refusal on Large Boulder LOG OF TEST HOLES PAUL NA~GLE LA~E R/VER, ALASiKA j LO, O. No. B-OB TP 1 12-1-76 Ele~. 279.2 ...... Ai~ S~ples A GRAVELLY SAND w/ SO~.~ SILT Occasional Cobbles and Boulders TP 2 , Elev. 2~6.7 · z .12-1--76 ~ All. Samples A 5.0' SANDY GRAVEL w/ $O~ SILT 25-30% Cobbles Occasional Boulders Brown, Loose 2.0' --3.0' SANDY GRAVEL w/ TRACE SILT Hany Cobbles Occasional Boulders Dense, Wet SAb~Y GRAVEL TO GRAVE~L w/ SO,GE SA>~ Approximately 30% Cobbles and Boulders, Loose 15 0' T.D. Refusal on Large Boulders' 16.0' T.D Refusal on Large Boulders fE__~.' _ 12-3_____-76 ~LE: 1"=3' LOG OF TEST PITS PAUL ~]~NGLE EAGLE RIGOR, ALASKA IIF'B GRID. PROJ. NO 652178 O',¥O NO. B-04 · 'TP 3 Elev. 326.8 ' ~' m TP 4 ~-,~ ' 12-1-76 A'~I-samples A- ~ ~J~ .... 12-1-76 0.0' S~IDY GRAVEL w/ SOME SILT Many Cobbles Some Boulders Loose, Wet Elev. 271.0 AI~ Samples A 0.0' GRAVEL w/ SO~ SA~; TRACE TO SO~ SILT Many Cobbles Some Boulders 6.0~ GRAVEL w/ SO}~ SA/~D; TRACE TO S0~,~ SILT Approximately 20% Cobbles Occasional. Boulder , Wet Large Boulders @ 12.0' Refusal on Bedrock or Large Boulder 13.0' T.D. Approximately 30% Cobbles and Boulders @ 10.0' ~ -- 13.0' SANDY GRAVEL w/ TRACE SILT Dense, Wet Approximately 25% Cobbles and Boulders 18.0' T.D. : - ~-3-76 1"-3 ' LOG OF TEST PITS PAUL %IANGLE EAGLE RIVER, ALASKA ]~.NO 652178 (3- DATE: TO: FROM: SUBJECT: MEMORANDUM December 14, 1983 Planning Department Attention: Chris IIea]th and Environmental Protection S-6954A: Overlook Estates Subdivision The review of eighteen(18) soils logs submitted to this office on December ]_2, 1983 indicate the following: lots will support on-site sewer systems, however, soils characteristics will not be used to issue on-site sewer system permits. This departa~ent will request soils test per lot from the developer on the soils log format used by 'this department.~ John W. Lynn Environmental Specialist JWL/1 j w / 91 010 (4/76) MUNICIPALITY OF ANCHORAGE DEPARTMENT OF HEALTH & ENVIRONMENTAL PROTECTION Environmental Health Division CASE REVIEW WORKSHEET CASE NUMBER: DATE RECEIVED: COMMENTS DUE BY: S-6954A November 3, 1983 November 18, 1983 SUBDIVISION OR PROJECT TITLE: Blocks 1, 2, 3, 4, and Tract A Overloo,k Estates Subdivision ( "i ~i PUBLIC WATER AVAILABLE (:b ~) PUBLIC SEWER AVAILABLE (/ ) COMMUNITY WATER AVAILABLE / COMMENTS: We Des~ To Last ARMSTRONG & ASSOCIATES OONSULTING £NelNEERS ENGINEERING · PLANNING o SURVEYING MUNICIPALITY OF ANCHORAG~ DEPT, OF HEALTiI 1317 E"."ast 74th Avenue ENVI~ONMENT/,,L P~-,-~ECTiON Anchorage, Alaska 99507 (907) 349-6577 / Date: ........ ,:CZ.:../...z...-...¢.. ~ ..................................................... Job No. ,¢~.~0.~.;~ ................................................................. Re: . . .~. . . . .v. . c. .,C.~ c. . o. ,~ :. . . . . ~:. ~ . T, T_. . ./t. . .~. .:.~ ............................ Gentlemen: I am sending you ~Attached Sent by: [] Mail [] Under separate cover ~ Messenger Copies Date Description These are transmitted as checked: ] As requested '~For review and comment [] For approval ~.j Approved as submitted [] Approved as noted ] Returned for corrections ]For your use [] For bids due ..................................................................... [] Prints returned after loan to us If enclosures are not as listed, please notify us at once. SOILS INVESTIGATION Overlook Estates Anchorage, Alaska Prepared for Armstrong & Associates, Inc. SRA Box 571-1317 East 74th Anchorage, Alaska 99507 by R. W. CHRISTENSEN Consulting Engineer P.Oo Box 111248 Anchorage, Alaska 99511 (907) $45-0019 December 2, 1983 ,¢ R, W. Christensen, Consulting Engineer P.O. Box 111248* Anchorage, Alaaka 99511, (907) 345 - 0019 Armstrong & Associates, Inc. SRA Box 571-1317 East 74th Anchorage, Alaska 99507 Attention: Craig L. Templin December 2,.1983 i,!J, JHICI?ALI~'i' 0~' I,NCIIORAr~E /)EI>'F, O~ HEA!'Tii $~ [i.?./tRONiJ~Z~'il/"L ~;'' ~ LCiiON Soils Investigation Overlook Estates Eagle River, Alaska Gentlemen: This report presents the results of a soils investigation for Overlook Estates near Eagle River, Alaska. The purpose of the investigation was to provide soils data for design of on-site septic systems and roads. The scope of the investigation, as described in ~ proposal dated November 8, 1983, was planned based on discussions with Craig Templin of Armstrong and Associates, Inc., and John Lynn of the Municipality of Anchorage, Department of Health and Environmental Protection. Verbal authorization to proceed was given on November 14, 1983 by Craig Templin. Fourteen borings were drilled to depths ranging from 9.5 to 16.0 feet at the locations described on Plate 1. The borings were drilled with a Nodwell-mounted CME-55 drill rig equipped with hollow-and solid-flight augers. The boring locations were established in the field by Craig Templin. Most of the borings were drilled within about l0 feet of the intended locations. For the intended boring locations that proved to be inaccessible to the drilling equipment, as-drilled locations are noted on Plate 1. The field operations were supervised by R. W. Christensen, P.E. The borings were logged in accordance with the Unified Soil Classification System, as described on Plate 16. Bulk samples from auger cuttings were taken at depths of approximately 2.5, 59 10, and 15 feet. (The original intent to obtain split-spoon drive samples abandoned after meeting refusal on the first attempt and breaking the i,AUIqlCli~ALI-F'f OF /,ix;L. xRAGF: DEPI'. OF IlEA-HI & I],~Vli:.Oi%',.Eiql,'-,L FL.. i'LC~iON R. W. Christensen Consulting Engineer cobbles and boulders would render standard penetration tests meaningless and make sample recovery very difficult.) Logs of the borings are presented on Plates 2 through 15. Three percolation tests were performed in shallow boreholes about 8 inches in diameter located adjacent to Borings 3, 6, and 14. The percolation test holes were drilled to a depth of approximately 2.5 feet; all loose soil was removed, and the holes were filled with water to a depth of about 12 inches three times before percolation rates were measured. Percolation rates were measured by adding water to the hole to a depth of 6 inches and observing the water level at several time intervals until all the water had seeped into the ground. The percolation test results are presented on the boring logs. Grain size distribution tests (sieve analyses) were performed on several samples. The results of those tests were used to estimate the frost classification of the soils and to extrapolate the results of shallow percolation tests to deeper strata that may influence the design and performance of on-site septic systems. The results of the grain size tests are presented on the boring logs. The on-site soils appear .to be quite uniform to the depths explored (approximately ~6 feet)~ In general, the soils are granular, with a high percentage of~obbl'e§ and boulders. The actual percentage., of cobbles and boulders is difficult to estimate from the boreholes. However, based on the difficulty of drilling and frequent auger refusal, it probably exceeds 20 percent. Based on laboratory sieve analyses, the soil fraction smaller than about 2 inches is predominately gravel and sand with varying amounts of silt. The measured silt content of the minus 2-inch fraction ranged from 4 to 19 percent. If the 'test samples had included the particles larger than 2 inches, the percentage silt content would, of course, have been lower. All the soils encountered were dry to slightly moist~ The ground water table was not encountered in any of the borings. The measured percolation rates ranged from abo~t 1 to 9 minutes per inch. These rates a~pear to be consistent with the grain size characteristics of the on-site soils. Although the percolation tests were conducted in shallow boreholes (about 2.§ feet deep), the uniformity of the soil conditions suggests that similar percolation rates would apply throughout the depths explored. The on-site soils appear to be excellent for road construction. The compaction characteristics should be very good. The frost R. W. Christensen Consulfing Engineer classification of the majority of the soils is NFS to F1 with some (probably minor) amount of F2. If you have any questions concerning this report, please call. It has been a pleasure to assist you on this project. Very Truly Yours, RICHARD W. CHRISTENS£N Consulting Engineer rl Z o ~ /~/ '~ ~ .., ~ 1,,.~1 ~ ro ~ ~ I~1 ~ ~ // ~ / ~'~ UNSUBDIVIDED - U- BORING 2 3 5 6 7 8 9 10 11 12 13 14 LOCATION Lot2-BIk.1 8+33 Overlook Drive Lot4-Blk.2 Paramount Drive Lot6-Blk.2 Lot4-Blk.3 Lot2-Blk.3 Lot4-Blk.1 4+80 Vantage Ave. Lot6-Blk.1 10+35 Vantage Ave. Lot2-Blk.4 15+00 Vantage Ave. Lot4-Blk.4 DRILLED as staked 75 ft. S-SW from stake as staked 30 ft.+ E from stake as staked 80 ft. W-NW from stake as staked R. W. Christensen Consulting Engineer BORING LOCATION PLAN OVERLOOK ESTATES Eagle River, Alaska P/ale SYMBOLS TEST DATA Grain Size OTHER DESCRIPTIONS (%) Gravel Sand Silt TESTS SANDY GRAVEL numerous cobbles and boulders occasionally silty medium dense dry to slightly moist Boring terminated (auger refusal) ~ 14.5 ft. on 11/16/83 Ground water table not encountered Key: N= number of blows required to advance the sampler the last 12 inches of 18-inch drive B= bulk sample S= standard split-spoon sample (ASTM D 1586) S= 2.4-inch I.D. sampler 340-1b. hammer, 30-inch drop DEFT. OF R. W. Christensen Consulting Engineer LOG OF BORING OVERLOOK ESTATES Eagle River, Alaska P/ate 2 TEST DATA Grain Size OTHER SYMBOLS DESCRIPTIONS (%) Gravel Sand Silt TESTS tCb? 3P- SANDY GRAVEL -- "~' GM numerous cobbles and boulders __ occasionally silty -B i~l medium dense '.'~d:.0~ dry to slightly moist ~:~ fewer cobbles ~ numerous cobbles/boulders ... fewer cobbles Boring completed ~ 16,0 ft, on Ground water table not encountered Key: N= number of blows required to advance the sampler the last 12 inches of 18-inch drive B= bulk sample S= standard split-spoon sample (ASTM D 1586) S= 2.4-inch I.D. sampler 340-1b. hammer, 30-inch drop R. W. Christensen Consulting Engineer LOG OF BORING OVERLOOK ESTATES Eagle River, Alaska P/ate 3 ~ ' ,, TEST DATA : Grain Size OTHER ~ N ~¥MBoLS DESCRIPTIONS (%) GraVel Sand Silt TESTS · ~:!o')~..(,Gp_ SANDY GRAVEL -- ",%):~ GM numerous cobbles and boulders ~.( . ~-medium dense -~ ,~-' dry to slightly moist  fewer cobbles ~'~ clean, uniform, medi~ cobbles n~erous Boring completed (~ 16.0 ft. Ground water table not encountered Key: N= number of blows required to advance the sampler the last 12 inches of 18-inch drive B= bulk sample S= standard split-spoon sample (ASTM D 1586) S= 2.4-inch I.D. sampler 340-1b. hammer, 30-inch drop R. W. Christensen Consulting Engineer PERCOLATION TEST Elapsed Time Water Depth (min:sec) (in.) 0 6 1:50 4 3:05 3 5:40 2 10~50 1 ', 19~50 0 ~ LOG OVERLOOK ESTATES Eagle River, Alaska Final Perc. Rate= 9.0 min/in OF BORING ~#3 Plate 4 ~ N SYMBOLS TEST DATA Grain Size OTHER DESCRIPTIONS (%) Gravel Sand Silt TESTS qDY' GRAVEL ~umerous cobbles and boulders ~ccasional ly silty ~ed i um dense iry to slightly moist Lumerous cobbles ewer cobbles, with more silt ~umerous cobbles ,lean, uniform, medium uger refusal on cobble 'ring c°mpleted L~' 15'0 ft' 'ound water table not{~ .ncountered Key: N= number of blows required to advance the sampler the last 12 inches of 18-inch drive B= bulk sample S= standard split-spoon sample (ASTM D 1586) S= 2.4-inch I.D. sampler 340-1b. hammer, 30-inch drop R. W. Christensen Consulling Engineer' LOG OF BORING OVERLOOK ESTATES Eagle River, Alaska Plate 5 ,~ TEST DATA = Grain Size OTHER u~ N SYMBOkS DESCRIPTIONS (%) Gravel Sand Silt TESTS ~.':~.~'GP- SANDY GRAVEL -- .~..~.~ GM numerous cobbles and boulders · occasionally silty ---- O~. medium dense - ~.'~ dry to slightly moist -B 0'~'~, B ~:~.( ~e~ co~e~, ~th mo~e ~-,', ~.. Boring terminated (auger refusal) L~ 12.5 ft. on ~ ~/~ 7/~ Ground water table not encountered Key: N= number of blows required to advance the sampler the last 12 inches of 18-inch drive B= bulk sample S= standard split-spoon sample (ASTM D 1586) S= 2.4-inch I.D. sampler 340-1b. hammer, 30-inch drop R. W, Christensen Consulting Engineer LOG OF BORING OVERLOOK ESTATES Eagle River, Alaska Plate 6 0 TEST DATA '~ Grain Size OYHER sYMBoLs ' " DESCRIPTIONS (?~) Gravel Sand Silt TESTS ~OJGP-. SANDY GRAVEL ~..'~; ~ ~'~'"( GM numerous cobbles and boulders I ~"" B ~ ..C2 occasionally silty ~ q~:~:: k ;:.~:, ~medium dense ~:~ ~'dry to slightly moist ,~.'~'.~ ~.~ fe~er cobb~e~, ~th mo~ ~i~ B ~:~'C Boring completed ~ 16.0 ft. on Ground water table not encountered ~. Key: N= number of blows required to advance the sampler the last 12 inches of 18-inch drive B= bulk sample S= standard split-spoon sample (ASTM D 1586) S= 2.4-inch I.D. sampler 340-1b. ha,~er, 30-inch drop PERCOLATION TEST El_~sed Time Water Depth (min:sec) (in.) 0 6 1:55 5 4:10 4 5~05 3 8:15 2 9~55 1 14:55 0 Final Perc. Rate= 5 min/in R. W. Christensen Consulting Engineer LOG OF BORING OVERLOOK ESTATES Eagle River, Alaska P/ate 7 TEST DATA (%) Grain Size OTHER SYMBOLS DESCRIPTIONS Gravel Sand Silt TESTS ~3P- SANDY GRAVEL -- ~.~.~ GM numerous cobbles and boulders -- ~C occasionally silty - 3~ medium dense r~,C dry to slightly moist ~. fewer cobbles, with more silt Boring completed ~ 16.0 ft. on 11/17/83 Ground water table not Key: N= number of blows required to advance the sampler the last 12 inches of 18-inch drive B= bulk sample S= standard split-spoon sample (ASTM D 1586) S= 2.4-inch I.D. sampler 340-1b. hammer, 30-inch drop R. W. Christensen Consulting Engineer LOG OF BORING $7 OVERLOOK ESTATES Eagle River, Alaska Plate 8 TEST DATA Grain Size OTHER SYMBOLS DESCRIPTIONS (%) Gravel Sand Silt TESTS , ,o~?3P- SANDY GRAVEL Bi ~i~GM numerous cobbles and boulders , ~C~[ occasionally silty ~ ,>.~ '~< medium dense - ~ dry to slightly moist _ ~,~: a~ ~s~<ho~e ~.~ relocated) [ ~ ~ ~er ~o~e~, ~th more ~, ~? Boring terminated (auger refusal) ~ 15.0 fl, on Ground water table not encountered Key: N= number of blows required to advance the sampler the last 12 inches of 18-inch drive B= bulk sample S= standard split-spoon sample (ASTM D 1586) S= 2.4-inch I.D. sampler 340-1b. hammer, 30-inch drop R. W. Chrislensen Consulling Engineer LOG OF BORING ~.8 OVERLOOK ESTATES Eagle River, Alaska P/ale 9 SYMBOLS TEST DATA Grain Size OTHER DESCRIPTIONS (%) Gravel. Sand Silt TESTS SANDY GRAVEL numerous cobbles and boulders occasionally silty medium dense dry to slightly moist auger refusal (hole relocated) Boring terminated (auger refusal) ~ 10.0 ft. on 11/17/83 Ground water table not encountered Key: N= number of blows required to advance the sampler the last 12 inches of 18-inch drive B= bulk sample S= standard split-spoon sample (ASTM D 1586) S= 2.4-inch I.D. sampler 340-1b. hammer, 30-inch drop R. W. Christensen Consulting Engineer LOG OF BORING ~9 OVERLOOK ESTATES Eagle River, Alaska P/ate 10 TEST DATA Grain Size OTHER - o? SYMBOLS DESCRIPTIONS (/o) Gravel Sand Silt TESTS  ~!~'~SP- SANDY GRAVEL '.'~:'.;': GM numerous cobbles and boulders -~B .'.~';, occasionally silty ~;~ medium dense - dry to slightly moist -- ~o~ auger refusal (hole 2 > L.~. auger refusal (hole -- Boring kerm~na~ed {auger refusal) ~ ~5.5 ft. on Ground wat~r.tabie not encountered Key: N= number of blows required to advance the sampler the last 12 inches of 18-inch drive B= bulk sample S= standard split-spoon sample (ASTM D 1586) S= 2,4-inch I,D. sampler 340-1b. hammer, 30-inch drop R. W. Christensen Consulting Engineer LOG OF BORING ~10 OVERLOOK ESTATES Eagle River, Alaska Plale 11 TEST DATA Grain Size OTHER SYMBOLS DESCRIPTIONS (%) Gravel Sand Silt TESTS -- %!i~3P- SANDY GRAVEL )~'0 GM numerous cobbles and boulders - ~ ~.~ medium dense __ ~7.2<::~ dry to slightly moist -- ~. fewer cobbles, with more silt )',~.-~, ~ numerous cobbles/boulders Boring terminated (auger refusal) ~14,5 ft. on Ground water table not Key: N= number of blows required to advance the sampler the last 12 inches of 18-inch drive B= bulk sample S= standard split-spoon sample (ASTM D 1586) S= 2.4-inch I.D. sampler 340-1b. hammer, 30-inch drop R. W. Christensen Consulling Engineer LOG OF BORING OVERLOOK ESTATES Eagle River, Alaska Plate 12 UJ ~ TEST DATA ~L m Grain Size OTHER ~ N SYMBOLS DESCRIPTIONS (%) Gravel Sand Silt TESTS .: 37- SANDY 'GRAVEL - B 3:.'eqGM numerous cobbles and boulders ~ occasionally silty .'- ' medium dense ;,o,~.?, dry to slightly mci. st ,.~.,~ auger refusal (hole Boring terminated (auger Ground water table not encountered Key~ N: number of blows renu±red to advance the sampler the last ~ inches of ~8-inch d~±ve B= bulk sample S= standard split-spoon sample (ASTM D 1586) S= 2.4-inch I.D. sampler 340-1b. halmaer, 30-inch drop R. W. Chrislensen Consulting Engineer LOG OF BORING ~12 OVERLOOK ESTATES Eagle River, Alaska Plate 13 SYMBOLS DESCRIPTIONS SANDY GRAVEL TEST DATA Grain Size OTHER Gravel SaBd Silt TESTS numerous cobbles and boulders occasionally silty medium dense dry to slightly moist Boring terminated (auger refusal) ~ 9.5 ft. on 11/18/83 Ground water table not encountered Key: N= number of blows required to advance the sampler the last 12 inches of 18-inch drive B= bulk sample S= standard split-spoon sample (ASTM D 1586) S= 2.4-inch I.D. sampler 340-1b. hammer, 30-inch drop R. W. Chrislensen Consulting Engineer LOG OF BORING OVERLOOK ESTATES Eagle River, Alaska P/ale 14 -'~ TEST DATA ~ ~ Grain Size OTHER SYMBOLS i DESCRIPTIONS (~) Gravel Sand Silt TESTS ~' .~.Gp.. SANDY GkAVEL -- "..'.' GM numerous cobbles and boulders - B ~j'~ir occasionally silty i~!~ medium dense ~.~ dry to slightly moist Boring terminated (auger refusal) 1/1 Ground water table not encountered Key: N= number of blows required to advance the sampler the last 12 inches of 18-inch drive B= bulk sample S= standard split-spoon sample (ASTM D 1586) S= 2.4-inch I.D. sampler 340-1b. hammer, 30-inch drop PERCOLATION TEST Elapsed Time Water Depth (min~sec) (in.) 0 6 1:50 4 2:30 3 4~05 1 5~10 0 Final Perc. Rate= 1.0 min/in R. W. Christensen Consulting Engineer LOG OF BORING ¢14 OVERLOOK ESTATES Eagle River, Alaska Plate 15 SOIL CLASSIFICATION SYSTEM GROUP i MAJOR [~IVI$[ONS SYMBOLSI TYPICAL NAMES PARTICLE SI Z I[ LIMITS RELATIVE DENSITY (sand-siltl CONSISTENCY (clay) R. W. Christensen Consulting Engineer UNIFIED SOIL CLASSIFICATION SYSTEM Plate 16 COR - UNSUBDIVIDED- BLOCI 2 - UNSUBDIVIDED - N S 5 VANTAGE BL CK 4 TRACT A NOTARY PRELIMINARY PLAT ui~SUBgI~D UNSUBDIVIDED '~q-['31 , _ ' ^ ~L C [,~[SERVE AREA PL~sN PRELIMINARY PLAT UNSUBDIVIDED ~ 2:, RESERVE AREA PLAN DT1001230 A pR~.~IMARy P]hAT OF OVERLOOK ESTATES SUBDIVISION