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HomeMy WebLinkAboutARAPAHOE FARM TOWNHOMES PUD - PRELIMINARY - 55-87G - SUBMITTAL DOCUMENTS - ROUND 1 - GEOTECHNICAL (SOILS) REPORT • • ARAPAHOE FARM TOWNHOMES PUD PHYSIOGRAPHIC DATA October 25, 1993 • 67 .Cr) co ��.Maii \ a' 80i �` a o �� M ��6 m o rn M . • • .. • v J/ °° \ o n o 0 n. , .,• ..,,......, n B '(.1/. � c� sor � T47, ', Y a / , , . ropwr,;4. 4, :_,:) . . ,,Tur .,,,,5_,)..:, _... ...:(5N1-. _ .. , ,t,„ , ,_J ... Air . Ail, 1,„,,,,(, . , :: 003AiJ1 , �� m x ,.,...:. M - ao t74f : �� II o� mo\, .b. 0up!,' LO NZ .. .1 .. 'IDCr) a �u7 M �' n. �,/ n r r O O cN ,-^ 4A LC) 1:.',0, i s ..SAL a S \ , J 601.1Th r INr- GA � a m M,,, ..,.. og j n a' rn .. ,J... 7., 4r : �n•or" a .. 75 •.•1I a . ' fil_,,,,_„ d. rn a)3,40i ,.. r-1 Y co t �r E a ( r .;. 1 y� O ' I. O O 0 o cco m C U ... tDn . ., rNbii, , , . . +.". 72:17',•.: k. , , . . .1- 0 '',;4, og - co li, ., . - + y _____,:, . .III S�. O' •4` .f ' '' n L O 'L I Z ,0 d'to LC, 0 O N. J O m H O v • • • 42 SOIL SURVEY 4/3) moist;moderate medium and coarse 30 inches. Sand and gravel are below a depth of 40 prismatic structure parting to moderate inches in some profiles. Some profiles have substrata medium subangular blocky; very hard, with a redder hue. firm, very sticky and very plastic; thin 73—Nunn clay loam, 0 to 1 percent slopes. This nearly continuous clay films on peds; level soil is on high terraces and fans. This soil has a noncalcareous; mildly alkaline; clear profile similar to the one described as representative of smooth boundary. the series, but the combined thickness of the surface B3ca-24 to 29 inches; pale brown (10YR 6/3) layer and subsoil is about 35 inches. clay loam, brown (10YR 5/3) moist; Included with this soil in mapping are small areas weak medium subangular blocky strut- of soils that are more sloping. Also included are a few ture; very hard, firm, very plastic; few small areas of Satanta, Fort Collins, and Ulm soils and thin patchy films. on ped faces; visible a few small areas of soils that have a surface layer and calcium carbonate occurring as small subsoil of silty clay loam. nodules; calcareous; moderately alka- Runoff is slow, and the hazard of erosion is slight. line; gradual smooth boundary. If irrigated, this soil is suited to corn, sugar beets, Clca-29 to 47 inches; light yellowish brown beans, barley, wheat, and alfalfa. Under dryland (10YR 6/4) clay loam, dark yellowish management it is suited to wheat or barley. It is also brown (10YR 4/4) moist; massive; very suited to pasture and native grasses. Capability units hard, firm, sticky and plastic; visible Its-1, irrigated, and IIIc-1, dryland; Clayey Foothill calcium carbonate occurring as nodules, range site; windbreak suitability group 1. thin seams, and streaks; calcareous; 74—Nunn clay loam, 1 to 3 percent slopes. This moderately alkaline; gradual smooth nearly level soil is on high terraces and fans. This soil boundary. has the profile described as representative of the C2ca-47 to 60 inches; light yellowish brown series. (2.5Y 6/3) clay loam, light olive brown Included with this soil in mapping are a few small (2.5Y 5/3) moist; massive; very hard, areas of soils that are more sloping or less sloping and firm, sticky and plastic; some visible a few small areas of soils that have a surface layer and calcium carbonate but less than in the subsoil of silty clay loam. Also included are small areas C1ca horizon; calcareous; moderately of Satanta, Fort Collins, and Ulm soils. alkaline. Runoff is slow to medium, the hazard of wind erosion The A horizon is light clay loam or clay loam 10 to is slight, and the hazard of water erosion is moderate. 12 inches thick in cultivated areas. The combined thick- If irrigated, this soil is suited to corn, sugar beets, ness of the A and B horizons ranges from 16 to 40 beans, barley, alfalfa, and wheat. Under dryland inches. The B2t horizon is heavy clay loam or light management it is suited to wheat and barley. It is also clay. Depth to calcareous material ranges from 10 to well suited to pasture or native grasses (fig. 10). • ,. a s:1. -�a1':,:Nic.rt'Y--•.�.3 ""� 4 t,n �. '�`^ � Ytl r a ,+ �,y+�y,r'Mr�.wt' ,k '��+ ,�=,.. _-_ .,��IR4„lj,A.�v'"few*, i " t' 'ri,r'Y.. i W "k. i'Y (" �tw 4 ', .�1�', } 1 h1h�, i� i"'.?t� 531Yf �. �+.V fr ..r Y,.�'�t 4"S[t'"'y Y�e` 1� (f?'il u �� ,i 't.'7 -- •' ,1 7"'.t+•�5-r r p 4' T, AiSi> ri:-.M r`rt r ,a.,.x�t+,rr•...,yw*N' j •. �J•: ,1.� r .t y.y4 .. h9F "•�. �ty�i'1/4. t. V!'F;r y'�'p�rh a4.e ' R��., �� 1••• ' e?r 4'4,T•)•t'tot' N ,1 r . 1g�..f,.. `.7 lti l,•, • 1` # 4 ...i' r+ ,`r" �' 441', }:r gyp{,'*` ,i, tyr e , ,' •. ` 4, 'rM ,Q1� •;. ",t &' A' t 4 F.}!�n ^ Y "`,�• T +,4. 1 w'1. ,i 4�'r �7 a`' f �,. Y"5`• � s'. �"� at ¢� k '",p . y �,. �.i tq r .�q+e�, w:�, �,.�, A. aj yt.� '� � ��` •. '+i C'.let"'4"+ � 7� 'r, Y T" '�f 'i "i V Y, �T,.t4` 1 ?M\��}'tl'I 1 v �••.C'��'JIY�'.�+- >♦ .'x ''� '"N'.•�fr .7,�.�4." .. .' k'+w .. ,', ...Y^•;' `�11.1 1,+,' ' ` 4 e tt ' .�'.F�Rr M oM1]Nlo d.'1,vt r,. • ''.+y .I. «�,rl '.` 9 r .� r7li.4 ? O Y,°K. ' t +� • `�,Y w1t ' t�i 1 i ' .+ t�� Y �+il�e�, 1 x. ,,dry 'e'f. �d.4i. 'a';$ . e1.sr .ri 4• " '$?r '**14 ri'� 4 F 6. fi , ' .2:t"� 1 f 1•w, 4• 4 i�,s-0 ! ,,... stp ` . K 1,A t.k ,y4 y +,. . '. y„ " , � i4^� 1 � � , - the fir• s `. �.,�.' yji,;,'. 1 `I•t y, i.y`1, f :! 1 ' �k�k.r ".,.a w„ p ' a w4.4 f. 4� `" , K Y,/s ,..e:.�r" 4Fr. .�t.5' .' ' yam•+ ' ` 4 ��i ,• '''` S ''' 'A . ,y111 ry +" l e 4, -" . ,4 ' ' Oe r,r t YS•.. 7 -' C. • a .'C. .,.y,. 4 i.. q r: Figure 10.—Alfalfa bales on Nunn clay loam, 1 to 3 percent slopes. • • • LARIMER COUNTY AREA, COLORADO 43 Capability units IIe-1, irrigated, and IIIe-6, dryland; Representative profile of Otero sandy loam in an 4 Clayey Foothill range site; windbreak suitability group area of Otero-Nelson sandy foams, 3 to 25 percent 1. slopes, in native grass, about 300 feet south and 1,420 75—Nunn clay loam, 3 to 5 percent slopes. This feet west of the northeast corner of sec. 11, T. 10 N., gently sloping soil is on high terraces and fans. This R. 68 W.: soil has a profile similar to the one described as rep- A1-0 to 4 inches; brown (10YR 5/3) sandy resentative of the series, but the combined thickness loam, dark brown (10YR 3/3) moist; of the surface layer and subsoil is about 24 inches. weak very fine granular structure; soft, Included with this soil in mapping are small areas very friable; calcareous; mildly alka- of soils that are more sloping or less sloping and a few line; clear smooth boundary. small areas of soils that have a surface layer of light Clca-4 to 17 inches; pale brown (10YR 6/3) clay. Also included are a few small areas of Satanta sandy loam, brown (10YR 5/3) moist; and Ulm soils. weak medium and coarse subangular Runoff is medium. The hazard of water erosion is blocky structure; hard, very friable; cal- moderate, and the hazard of wind erosion is slight. careous; visible calcium carbonate as few If irrigated, this soil is suited to barley, alfalfa, and soft spots; moderately alkaline; gradual wheat and, to a lesser extent, corn, sugar beets, and smooth boundary. beans. Under dryland management it is suited to wheat C2ca-17 to 60 inches; light brownish gray or barley. It is also well suited to pasture and native (10YR 6/2) sandy loam, dark grayish grasses. Capability units IIIe-2, irrigated, and IIIe-7, brown (10YR 4/2) moist;massive;hard, dryland; Clayey Foothill range site; windbreak suit- very friable; calcareous; visible calcium ability group 1. carbonate as few soft spots; moderately 76—Nunn clay loam, wet, 1 to 3 percent slopes. This alkaline. nearly level, somewhat poorly drained soil is on low The A horizon is sandy loam or fine sandy loam 8 to terraces and alluvial fans, commonly adjacent to 12 inches thick in cultivated areas. The C horizon is drainageways. This soil has a profile similar to the one sandy loam or fine sandy loam. The soil is generally described as representative of the series, but a seasonal calcareous throughout, but the surface layer is leached high water table is at a depth of 20 to 30 inches during in places. Distribution of lime in the profile is erratic. part of the growing season. Soft sandstone is at a depth of 40 to 60 inches in some Included with this soil in mapping are a few small profiles. areas of soils that have a strongly alkaline surface 77—Otero sandy loam, 0 to 3 percent slopes. This layer and a few small areas of soils that are moderately nearly level soil is on uplands and fans. This soil has a well drained. Also included are a few areas of soils profile similar to the one described as representative of that have a surface layer of loam or clay and a few the series, but the surface layer is about 10 to 12 areas of soils that are less sloping. inches thick. Runoff is slow, and the hazard of erosion is slight. Included with this soil in mapping are some small This soil is suited to pasture and hay. If the water areas of soils that have a surface layer of loam or fine table is lowered by management practices, corn, sugar sandy loam. Also included are some areas of soils that t beets, wheat, and barley can be grown. Capability unit are redder and a few small areas of Ascalon, Nelson, IIIw-1, irrigated; Wet Meadow range site; windbreak and Kim soils. suitability group 5. Runoff is slow. The hazard of water erosion is slight, and the hazard of wind erosion is moderate. ar ' Otero Series beets, wheat,If anated, d beans. Unde soil is r dryland to e barley,man management g The Otero series consists of deep, well drained soils it is suited o pasture and native grasses and, to a that formed in alluvium and wind-deposited material. lesser extent, wheat and barley. Capability units These soils are on alluvial fans and terraces. Elevation IIIe-5, irrigated, and IVe-5, dryland; Sandy Plains ranges from 4,800 to 5,600 feet. Slopes are 0 to 15 range site; windbreak suitability group 2. 78—Otero sandy loam, 3 to 5 percent slopes. This percent. The native vegetation is mainly blue grams, gently sloping soil is on uplands and fans. This soil needlegrass, bluestems, and some forbs and shrubs. has a profile similar to the one described as represents- Mean annual precipitation ranges from 13 to 15 inches, tive of the series, but the surface layer is about 8 mean annual air temperature ranges from 48° to 50° Y F, and the frost-free season ranges from 135 to 150 inches thick. days. Included with this soil in mapping are a few small In a representative profile the surface layer is brown areas of soils that are more sloping or less sloping. Also included are some small areas of soils in which sandy loam about 4 inches thick. The underlying sandstone is at a depth of 40 to 60 inches and a few material is pale brown sandy loam about 13 inches light brownish gray sandy loam. small areas of Ascalon, Nelson, and Kim soils. thick over Runoff is medium, and the hazard of erosion is Permeability is rapid, and the available water ca- moderate. pacity is medium. Reaction is mildly alkaline above a If irrigated, this soil is suited to barley, wheat. depth of about 4 inches and moderately alkaline below alfalfa, and pasture and, to a lesser extent, corn and that depth. beans. Under dryland management it is well suited to These soils are used mainly for native grasses and pasture and native grasses. Capability units IIIe-4, for dryfarmed crops. A few areas are used for ir- irrigated, and VIe-2, dryland; Sandy Plains range rigated crops. site; windbreak suitability group 2. , - • • eil 132 SOIL SURVEY TABLE 8.—Soil and water features—Continued Flooding Depth to Bedrock 1; Soil name and Hydro- seasonal Potential 1` ma s bol logic high frost p Ym group water action Frequency Duration Months table Depth Hardness s Kirtley—Continued: *58: Feet Inches Kirtley part C None >6.0 20-40 Rippable__ Moderate. Punier part D None >6.0 10-20 Hard Low. d LaPorte: *59: LaPorte part C None >6.0 10-20 Rippable Rock outcrop part. __ Low. Larim: 60 A None >6.0 >60 Low. i Larimer: 61 B None >6.0 >60 Low. *62: Larimer part B None >6.0 >60 Low. Stoneham part B None >6.0 >60 Moderate. Longmont: 63 C Common ____ Brief March-July __ 2.0-2.5 >60 High. Loveland: 64 C Common ____ Very brief ___ March- 1.5-2.5 >60 High. September. Midway: 65 D None >6.0 10-20 Rippable __ Moderate. Minnequa: 66 B None >6.0 20-40 Rippable__ Low. it *67: Minnequa part B None >6.0 20-40 Rippable__ Low. LaPorte part C None >6.0 10-20 Rippable__ Low. Miracle: 68 B None >6.0 20-40 Hard Moderate. Naz: 69, 70 A None >6.0 >60 Hard Moderate. Nelson: 71 B None >6.0 20-40 Rip pable __ Low. Newf ork: 72 D Occasional ___ Brief April-July ___ 0.5-4.0 >60 Low. Nunn: 73, 74, 75 C None >6.0 >60 Moderate. 76 C None 1.5-2.5 >60 Moderate. Otero: 77, 78, 79 B None >6.0 >60 Low. *80: Otero part B None >6.0 >60 Low. Nelson part B None >6.0 20-40 Rippable __ Low. Paoli: 81 B Rare Very brief ___ May-June ___ >6.0 >60 Moderate. Pendergrass: *82: Pendergrass part ___ D None >6.0 10-20 Hard Low. Rock outcrop part. II! ______ — ____, • •ARIMER COUNTY AREA, COLORADO * 139 TABLE 9.—Building site development—Continued Soil name and Shallow Dwellings without Dwellings with Small commercial Local roads and map symbol excavations basements basements buildings streets *62—Cont.: Stoneham part ____ Slight Moderate: frost Moderate: frost Moderate: slope; Severe: low action;shrink- action; shrink-swell; strength. swell. shrink-swell. frost action. Longmont: 63 Severe: wetness; Severe: wetness; Severe: wetness; Severe: wetness; Severe: frost floods;too floods. floods. floods; corrosive. action;wetness; clayey. shrink-swell. Loveland: 64 Severe: wetness; Severe: floods; Severe: floods; Severe: wetness; Severe: frost floods. wetness. wetness. floods;corrosive. action;wetness; shrink-swell. Midway: ri 65 Severe: slope; Severe: slope; Severe: slope; Severe: slope; Severe: slope; too clayey. shrink-swell. shrink-swell; shrink-swell; shrink-swell. depth to rock. corrosive. Minnequa: 66 Moderate: depth Slight Moderate: depth Moderate: Moderate: low (, to rock. to rock. slope. strength. *67: Minnequa part ____ Moderate: depth Moderate: Moderate: depth Severe: slope ____ Moderate: low to rock;slope. slope. to rock;slope. strength;slope. LaPorte part Severe: depth to Severe: depth to Severe: depth to Severe: depth to Severe: depth to rock. rock. rock. rock. rock. Miracle: 68 Severe: depth to Severe: slope ____ Severe: slope; Severe: slope ____ Severe: slope. rock;slope. depth to rock. Naz: 69 Slight Slight Slight Slight Moderate: frost action. 70 Severe: slope ____ Severe: slope ____ Severe: slope ____ Severe: slope ____ Severe: slope. Nelson: 71 Severe: depth to Moderate: depth Severe: depth to Moderate: depth Moderate: depth rock. to rock. rock. to rock;slope; to rock;frost corrosive. action. Newfork: 72 Severe: wetness; Severe: floods; Severe: floods; Severe: floods; Severe: floods; small stones; wetness. wetness. wetness. wetness. floods. Nunn: 73, 74, 75 Moderate: too Severe: Moderate: Severe: Severe: shrink- clayey. shrink-swell. shrink-swell. shrink-swell; swell;low corrosive. strength. 76 Severe: Severe: Severe: Severe: Severe: shrink- wetness. shrink-swell. wetness. shrink-swell; swell;low corrosive. strength. Otero: 77 Slight Slight Slight Slight Slight. 78, 79 Slight Slight Slight Moderate: Slight. slope. *80: Otero part Severe: slope ____ Severe: slope ____ Severe: slope ____ Severe: slope ____ Severe: slope. Nelson part Severe: depth to Severe: slope ____ Severe: depth to Severe: slope ____ Severe: slope. rock;slope. rock; slope.