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HomeMy WebLinkAboutSDP201500033 Study 2015-07-151 I i re! L1 lQ t.J1 r Thomas Jefferson Soil and Water rI - - ' N Conservation District ma" % ` \ 5a / 706 Forest St, SteG,Charlottesville, VA22903 l ;,^"uvanne;' ~\ l I Tel: (434) 975-0224 Fax: (434) 975-1367 Web Page: www.tiswcd.orq July 15, 2015 TO: Albemarle County Department of Community Development— Division of Planning RE: Soils Report for: Site Review Committee Verizon Wireless "Greenbrier Park" Tier II Personal Wireless Service Facility r zz N M A 0009TZb OL6STZb Ob65Rb Oi65TZb 088STZb OS8STZb OZ85TZb 06LSRb co 08L O OM.Eba o8L N ,- ot,.. r.:.'.? 6(":- :: kr.?'- X 4 N 1 m 42 r 8 c,C F r. r' a ti m 1714. 8 t f *row • Z U r Y N r max 0- r. a w f6 I'c o 0 0 # lb:. % 44.,,,,,t1 A,,,,,,,„_ r 81o 1 4uaa E. o- • V s N VIa a ce is ct0O M,rs iz.ac 0885TZ' <.., I A."SS LZ o8L10009LZbOL65TZbOb65TZbOT6STZbb06LSTZb z G N Lt, CO O o O O '*C N NOCQ) v_ aCOCOOc as L.. OON2U N °5 I 3 . 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O -e -4 c00 > + : Soil Map—Albemarle County,Virginia TM61-P153A1 Map Unit Legend Albemarle County,Virginia(VA003) Map Unit Symbol Map Unit Name Acres in AO1 Percent of AOI 21B Culpeper fine sandy loam,2 to 3.8 100.0% 7 percent slopes Totals for Area of Interest 3.8 100.0% Natural Resources Web Soil Survey 7/15/2015 Conservation Service National Cooperative Soil Survey Page 3 of 3 Map Unit Description(Brief,Generated)--Albemarle County,Virginia TM61-P153A1 Map Unit Description (Brief, Generated) The map units delineated on the detailed soil maps in a soil survey represent the soils or miscellaneous areas in the survey area. The map unit descriptions in this report, along with the maps, can be used to determine the composition and properties of a unit. A map unit delineation on a soil map represents an area dominated by one or more major kinds of soil or miscellaneous areas. A map unit is identified and named according to the taxonomic classification of the dominant soils.Within a taxonomic class there are precisely defined limits for the properties of the soils. On the landscape, however, the soils are natural phenomena, and they have the characteristic variability of all natural phenomena. Thus, the range of some observed properties may extend beyond the limits defined for a taxonomic class. Areas of soils of a single taxonomic class rarely, if ever, can be mapped without including areas of other taxonomic classes. Consequently, every map unit is made up of the soils or miscellaneous areas for which it is named and some minor components that belong to taxonomic classes other than those of the major soils. The Map Unit Description (Brief, Generated) report displays a generated description of the major soils that occur in a map unit. Descriptions of non-soil miscellaneous areas) and minor map unit components are not included. This description is generated from the underlying soil attribute data. Additional information about the map units described in this report is available in other Soil Data Mart reports,which give properties of the soils and the limitations, capabilities,and potentials for many uses.Also,the narratives that accompany the Soil Data Mart reports define some of the properties included in the map unit descriptions. Report—Map Unit Description (Brief, Generated) Albemarle County, Virginia Map Unit: 21 B—Culpeper fine sandy loam, 2 to 7 percent slopes Component: Culpeper(80%) The Culpeper component makes up 80 percent of the map unit. Slopes are 2 to 7 percent. This component is on hillslopes, piedmonts. The parent material consists of residuum weathered from meta-arkosic sandstone and quartzite. Depth to a root restrictive layer, bedrock, lithic, is 40 to 79 inches. The natural drainage class is well drained. Water movement in the most restrictive layer is moderately high. Available water to a depth of 60 inches is moderate. Shrink-swell potential is moderate. This soil is not flooded. It is not ponded. There is no zone of water saturation within a depth of 72 inches.Organic matter content in the surface horizon is about 2 percent. Nonirrigated land capability classification is 2e. This soil does not meet hydric criteria. USDA Natural Resources Web Soil Survey 7/15/2015 Conservation Service National Cooperative Soil Survey Page 1 of 2 Map Unit Description(Brief,Generated)---Albemarle County,Virginia TM61-P153A1 Data Source Information Soil Survey Area: Albemarle County, Virginia Survey Area Data: Version 10, Dec 11, 2013 USDA Natural Resources Web Soil Survey 7/15/2015 2.1 Conservation Service National Cooperative Soil Survey Page 2 of 2 Dwellings and Small Commercial Buildings--Albemarle County,Virginia TM61-P153A1 Dwellings and Small Commercial Buildings Soil properties influence the development of building sites, including the selection of the site,the design of the structure,construction,performance after construction, and maintenance.This table shows the degree and kind of soil limitations that affect dwellings and small commercial buildings. The ratings in the table are both verbal and numerical. Rating class terms indicate the extent to which the soils are limited by all of the soil features that affect building site development. Not limited indicates that the soil has features that are very favorable for the specified use. Good performance and very low maintenance can be expected. Somewhat limited indicates that the soil has features that are moderately favorable for the specified use. The limitations can be overcome or minimized by special planning, design, or installation. Fair performance and moderate maintenance can be expected. Very limited indicates that the soil has one or more features that are unfavorable for the specified use. The limitations generally cannot be overcome without major soil reclamation, special design, or expensive installation procedures. Poor performance and high maintenance can be expected. Numerical ratings in the table indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the use (1.00) and the point at which the soil feature is not a limitation 0.00). Dwellings are single-family houses of three stories or less. For dwellings without basements, the foundation is assumed to consist of spread footings of reinforced concrete built on undisturbed soil at a depth of 2 feet or at the depth of maximum frost penetration, whichever is deeper. For dwellings with basements, the foundation is assumed to consist of spread footings of reinforced concrete built on undisturbed soil at a depth of about 7 feet. The ratings for dwellings are based on the soil properties that affect the capacity of the soil to support a load without movement and on the properties that affect excavation and construction costs.The properties that affect the load-supporting capacity include depth to a water table, ponding, flooding, subsidence, linear extensibility(shrink-swell potential), and compressibility. Compressibility is inferred from the Unified classification. The properties that affect the ease and amount of excavation include depth to a water table, ponding, flooding, slope, depth to bedrock or a cemented pan, hardness of bedrock or a cemented pan, and the amount and size of rock fragments. Small commercial buildings are structures that are less than three stories high and do not have basements. The foundation is assumed to consist of spread footings of reinforced concrete built on undisturbed soil at a depth of 2 feet or at the depth of maximum frost penetration, whichever is deeper. The ratings are based on the soil properties that affect the capacity of the soil to support a load without movement and on the properties that affect excavation and construction costs. The properties that affect the load-supporting capacity include depth to a water table, ponding, flooding, subsidence, linear extensibility(shrink-swell potential), and compressibility(which is inferred from the Unified classification).The properties that affect the ease and amount of excavation include flooding, depth to a water table, ponding, slope, depth to bedrock or a cemented pan, hardness of bedrock or a cemented pan, and the amount and size of rock fragments. USDA Natural Resources Web Soil Survey 7/15/2015 Conservation Service National Cooperative Soil Survey Page 1 of 2 Dwellings and Small Commercial Buildings---Albemarle County,Virginia TM61-P153A1 Information in this table is intended for land use planning, for evaluating land use alternatives, and for planning site investigations prior to design and construction. The information, however, has limitations. For example, estimates and other data generally apply only to that part of the soil between the surface and a depth of 5 to 7 feet. Because of the map scale, small areas of different soils may be included within the mapped areas of a specific soil. The information is not site specific and does not eliminate the need for onsite investigation of the soils or for testing and analysis by personnel experienced in the design and construction of engineering works. Government ordinances and regulations that restrict certain land uses or impose specific design criteria were not considered in preparing the information in this table. Local ordinances and regulations should be considered in planning, in site selection, and in design. Report—Dwellings and Small Commercial Buildings Onsite investigation may be needed to validate the interpretations in this table and to confirm the identity of the soil on a given site.The numbers in the value columns range from 0.01 to 1.00. The larger the value, the greater the potential limitation. The table shows only the top five limitations for any given soil. The soil may have additional limitations] Dwellings and Small Commercial Buildings–Albemarle County,Virginia map symbol and soil Pct.of Dwellings without basements Dwellings with basements Small commercial buildings name map unit Rating class and Value Rating class and Value ", Rating class and Value limiting features limiting features limiting features 21 B—Culpeper fine sandy loam,2 to 7 percent slopes Culpeper 80 Somewhat limited Somewhat limited Somewhat limited Shrink-swell 0.35 Depth to hard bedrock 0.42 Shrink-swell 0.35 Shrink-swell 0.15 Slope 0.13 Data Source Information Soil Survey Area: Albemarle County, Virginia Survey Area Data: Version 10, Dec 11, 2013 USDA Natural Resources Web Soil Survey 7/15/2015 211116 Conservation Service National Cooperative Soil Survey Page 2 of 2 Roads and Streets,Shallow Excavations,and Lawns and Landscaping--Albemarle County, TM61-P153A1 Virginia Roads and Streets, Shallow Excavations, and Lawns and Landscaping Soil properties influence the development of building sites, including the selection of the site,the design of the structure,construction,performance after construction, and maintenance.This table shows the degree and kind of soil limitations that affect local roads and streets, shallow excavations, and lawns and landscaping. The ratings in the table are both verbal and numerical. Rating class terms indicate the extent to which the soils are limited by all of the soil features that affect building site development. Not limited indicates that the soil has features that are very favorable for the specified use. Good performance and very low maintenance can be expected. Somewhat limited indicates that the soil has features that are moderately favorable for the specified use. The limitations can be overcome or minimized by special planning, design, or installation. Fair performance and moderate maintenance can be expected. Very limited indicates that the soil has one or more features that are unfavorable for the specified use. The limitations generally cannot be overcome without major soil reclamation, special design, or expensive installation procedures. Poor performance and high maintenance can be expected. Numerical ratings in the table indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the use (1.00) and the point at which the soil feature is not a limitation 0.00). Local roads and streets have an all-weather surface and carry automobile and light truck traffic all year.They have a subgrade of cut or fill soil material;a base of gravel, crushed rock,or soil material stabilized by lime or cement; and a surface of flexible material (asphalt), rigid material(concrete), or gravel with a binder. The ratings are based on the soil properties that affect the ease of excavation and grading and the traffic-supporting capacity. The properties that affect the ease of excavation and grading are depth to bedrock or a cemented pan, hardness of bedrock or a cemented pan, depth to a water table, ponding, flooding, the amount of large stones,and slope.The properties that affect the traffic-supporting capacity are soil strength (as inferred from the AASHTO group index number), subsidence, linear extensibility(shrink-swell potential), the potential for frost action, depth to a water table, and ponding. Shallow excavations are trenches or holes dug to a maximum depth of 5 or 6 feet for graves, utility lines, open ditches, or other purposes. The ratings are based on the soil properties that influence the ease of digging and the resistance to sloughing. Depth to bedrock or a cemented pan, hardness of bedrock or a cemented pan,the amount of large stones, and dense layers influence the ease of digging,filling, and compacting. Depth to the seasonal high water table, flooding, and ponding may restrict the period when excavations can be made. Slope influences the ease of using machinery. Soil texture, depth to the water table, and linear extensibility shrink-swell potential) influence the resistance to sloughing. USDA Natural Resources Web Soil Survey 7/15/2015 Conservation Service National Cooperative Soil Survey Page 1 of 3 Roads and Streets,Shallow Excavations,and Lawns and Landscaping---Albemarle County, TM61- P153A11` Virginia Lawns and landscaping require soils on which turf and ornamental trees and shrubs can be established and maintained. Irrigation is not considered in the ratings. The ratings are based on the soil properties that affect plant growth and trafficability after vegetation is established.The properties that affect plant growth are reaction; depth to a water table; ponding; depth to bedrock or a cemented pan;the available water capacity in the upper 40 inches; the content of salts, sodium, or calcium carbonate; and sulfidic materials. The properties that affect trafficability are flooding,depth to a water table,ponding,slope,stoniness,and the amount of sand, clay, or organic matter in the surface layer. Information in this table is intended for land use planning, for evaluating land use alternatives, and for planning site investigations prior to design and construction. The information, however, has limitations. For example, estimates and other data generally apply only to that part of the soil between the surface and a depth of 5 to 7 feet. Because of the map scale, small areas of different soils may be included within the mapped areas of a specific soil. The information is not site specific and does not eliminate the need for onsite investigation of the soils or for testing and analysis by personnel experienced in the design and construction of engineering works. Government ordinances and regulations that restrict certain land uses or impose specific design criteria were not considered in preparing the information in this table. Local ordinances and regulations should be considered in planning, in site selection, and in design. Report—Roads and Streets, Shallow Excavations, and Lawns and Landscaping Onsite investigation may be needed to validate the interpretations in this table and to confirm the identity of the soil on a given site.The numbers in the value columns range from 0.01 to 1.00. The larger the value, the greater the potential limitation. The table shows only the top five limitations for any given soil. The soil may have additional limitations] Roads and Streets,Shallow Excavations,and Lawns and Landscaping–Albemarle County,Virginia Map symbol and soli Pct.of Local roads and streets Shallow excavations Lawns and landscaping name map unit Rating class and Value Rating classand Value Rating class and Value limiting features limiting features limiting features 2113—Culpeper fine sandy loam,2 to 7 percent slopes Culpeper 80 Very limited Somewhat limited Very limited Low strength 1.00 Depth to hard bedrock 0.42 Low exchange 1.00 capacity Frost action 0.50 Too clayey 0.13 Too clayey 0.50 Shrink-swell 0.35 Dusty 0.04 Dusty 0.04 Unstable excavation 0.01 walls USDA Natural Resources Web Soil Survey 7/15/2015 2" Conservation Service National Cooperative Soil Survey Page 2 of 3 Roads and Streets,Shallow Excavations,and Lawns and Landscaping---Albemarle County, TM61-P153A1 Virginia Data Source Information Soil Survey Area: Albemarle County, Virginia Survey Area Data: Version 10, Dec 11, 2013 USDA Natural Resources Web Soil Survey 7/15/2015I". Conservation Service National Cooperative Soil Survey Page 3 of 3 Soil Features---Albemarle County,Virginia TM61-P153A1 Soil Features This table gives estimates of various soil features. The estimates are used in land use planning that involves engineering considerations. A restrictive layer is a nearly continuous layer that has one or more physical, chemical, or thermal properties that significantly impede the movement of water and air through the soil or that restrict roots or otherwise provide an unfavorable root environment. Examples are bedrock, cemented layers, dense layers, and frozen layers.The table indicates the hardness and thickness of the restrictive layer, both of which significantly affect the ease of excavation. Depth to top is the vertical distance from the soil surface to the upper boundary of the restrictive layer. Subsidence is the settlement of organic soils or of saturated mineral soils of very low density. Subsidence generally results from either desiccation and shrinkage, or oxidation of organic material,or both,following drainage.Subsidence takes place gradually, usually over a period of several years. The table shows the expected initial subsidence,which usually is a result of drainage,and total subsidence,which results from a combination of factors. Potential for frost action is the likelihood of upward or lateral expansion of the soil caused by the formation of segregated ice lenses(frost heave)and the subsequent collapse of the soil and loss of strength on thawing. Frost action occurs when moisture moves into the freezing zone of the soil. Temperature, texture, density, saturated hydraulic conductivity(Ksat),content of organic matter,and depth to the water table are the most important factors considered in evaluating the potential for frost action. It is assumed that the soil is not insulated by vegetation or snow and is not artificially drained. Silty and highly structured, clayey soils that have a high water table in winter are the most susceptible to frost action.Well drained, very gravelly, or very sandy soils are the least susceptible. Frost heave and low soil strength during thawing cause damage to pavements and other rigid structures. Risk of corrosion pertains to potential soil-induced electrochemical or chemical action that corrodes or weakens uncoated steel or concrete. The rate of corrosion of uncoated steel is related to such factors as soil moisture, particle-size distribution, acidity, and electrical conductivity of the soil. The rate of corrosion of concrete is based mainly on the sulfate and sodium content,texture, moisture content,and acidity of the soil.Special site examination and design may be needed if the combination of factors results in a severe hazard of corrosion. The steel or concrete in installations that intersect soil boundaries or soil layers is more susceptible to corrosion than the steel or concrete in installations that are entirely within one kind of soil or within one soil layer. For uncoated steel,the risk of corrosion, expressed as low, moderate, or high, is based on soil drainage class, total acidity, electrical resistivity near field capacity, and electrical conductivity of the saturation extract. For concrete, the risk of corrosion also is expressed as low, moderate, or high. It is based on soil texture, acidity, and amount of sulfates in the saturation extract. USDA Natural Resources Web Soil Survey 7/15/2015 Conservation Service National Cooperative Soil Survey Page 1 of 2 Q o) 141a p LC)N N 0N M r 0) L.i"-:: a c a) a) 0 0 m m C.._ 4) N 0 m u_ m wV m m w 0 C L G V0, 2 F O To V d woa 2 at t 1... a IS J s c c a) S Cl) .? To s I I E E a c El Zu m o a) c oa m 2 u d c‘') f/) C M ON c 5 Cv wOc aU) vi t s I Ico e Vo Q' ti i w m° o= ov dS 4- E cu y D s v v C N LL CD Y Q u CD o id m z 0cl.a '.N _ s,L f'0 N c7 Y L a 0 >, mco 0 o aii ea = "e N. U IL 0 y ir,N N CI U) n10 " gl 6Eco Q a m ml ct c n W 2 a) 3 2 c`74 y n 0 c m a)U- 0 Physical Soil Properties--Albemarle County,Virginia TM61-P153A1 Physical Soil Properties This table shows estimates of some physical characteristics and features that affect soil behavior. These estimates are given for the layers of each soil in the survey area.The estimates are based on field observations and on test data for these and similar soils. Depth to the upper and lower boundaries of each layer is indicated. Particle size is the effective diameter of a soil particle as measured by sedimentation, sieving, or micrometric methods. Particle sizes are expressed as classes with specific effective diameter class limits. The broad classes are sand, silt, and clay, ranging from the larger to the smaller. Sand as a soil separate consists of mineral soil particles that are 0.05 millimeter to 2 millimeters in diameter. In this table,the estimated sand content of each soil layer is given as a percentage,by weight,of the soil material that is less than 2 millimeters in diameter. Silt as a soil separate consists of mineral soil particles that are 0.002 to 0.05 millimeter in diameter. In this table,the estimated silt content of each soil layer is given as a percentage, by weight, of the soil material that is less than 2 millimeters in diameter. Clay as a soil separate consists of mineral soil particles that are less than 0.002 millimeter in diameter. In this table,the estimated clay content of each soil layer is given as a percentage,by weight,of the soil material that is less than 2 millimeters in diameter. The content of sand, silt, and clay affects the physical behavior of a soil. Particle size is important for engineering and agronomic interpretations,for determination of soil hydrologic qualities, and for soil classification. The amount and kind of clay affect the fertility and physical condition of the soil and the ability of the soil to adsorb cations and to retain moisture.They influence shrink- swell potential, saturated hydraulic conductivity(Ksat), plasticity, the ease of soil dispersion, and other soil properties. The amount and kind of clay in a soil also affect tillage and earthmoving operations. Moist bulk density is the weight of soil (ovendry) per unit volume.Volume is measured when the soil is at field moisture capacity, that is,the moisture content at 1/3-or 1/10-bar(33kPa or 10kPa) moisture tension. Weight is determined after the soil is dried at 105 degrees C. In the table,the estimated moist bulk density of each soil horizon is expressed in grams per cubic centimeter of soil material that is less than 2 millimeters in diameter. Bulk density data are used to compute linear extensibility,shrink-swell potential, available water capacity,total pore space, and other soil properties. The moist bulk density of a soil indicates the pore space available for water and roots.Depending on soil texture,a bulk density of more than 1.4 can restrict water storage and root penetration. Moist bulk density is influenced by texture, kind of clay, content of organic matter, and soil structure. USDA Natural Resources Web Soil Survey 7/15/2015IiiConservationServiceNationalCooperativeSoilSurveyPage1of4 Physical Soil Properties---Albemarle County,Virginia TM61-P153A1 Saturated hydraulic conductivity(Ksat) refers to the ease with which pores in a saturated soil transmit water. The estimates in the table are expressed in terms of micrometers per second. They are based on soil characteristics observed in the field, particularly structure, porosity, and texture. Saturated hydraulic conductivity Ksat) is considered in the design of soil drainage systems and septic tank absorption fields. Available water capacity refers to the quantity of water that the soil is capable of storing for use by plants.The capacity for water storage is given in inches of water per inch of soil for each soil layer.The capacity varies,depending on soil properties that affect retention of water. The most important properties are the content of organic matter,soil texture,bulk density,and soil structure.Available water capacity is an important factor in the choice of plants or crops to be grown and in the design and management of irrigation systems.Available water capacity is not an estimate of the quantity of water actually available to plants at any given time. Linear extensibility refers to the change in length of an unconfined clod as moisture content is decreased from a moist to a dry state. It is an expression of the volume change between the water content of the clod at 1/3-or 1/10-bar tension(33kPa or 10kPa tension) and oven dryness. The volume change is reported in the table as percent change for the whole soil.The amount and type of clay minerals in the soil influence volume change. Linear extensibility is used to determine the shrink-swell potential of soils. The shrink-swell potential is low if the soil has a linear extensibility of less than 3 percent; moderate if 3 to 6 percent;high if 6 to 9 percent;and very high if more than 9 percent. If the linear extensibility is more than 3, shrinking and swelling can cause damage to buildings, roads, and other structures and to plant roots. Special design commonly is needed. Organic matter is the plant and animal residue in the soil at various stages of decomposition. In this table,the estimated content of organic matter is expressed as a percentage, by weight, of the soil material that is less than 2 millimeters in diameter. The content of organic matter in a soil can be maintained by returning crop residue to the soil. Organic matter has a positive effect on available water capacity,water infiltration, soil organism activity,and tilth.It is a source of nitrogen and other nutrients for crops and soil organisms. Erosion factors are shown in the table as the K factor(Kw and Kf)and the T factor. Erosion factor K indicates the susceptibility of a soil to sheet and rill erosion by water.Factor K is one of six factors used in the Universal Soil Loss Equation(USLE) and the Revised Universal Soil Loss Equation (RUSLE)to predict the average annual rate of soil loss by sheet and rill erosion in tons per acre per year. The estimates are based primarily on percentage of silt, sand, and organic matter and on soil structure and Ksat.Values of K range from 0.02 to 0.69.Other factors being equal,the higher the value,the more susceptible the soil is to sheet and rill erosion by water. Erosion factor Kw indicates the erodibility of the whole soil. The estimates are modified by the presence of rock fragments. Erosion factor Kf indicates the erodibility of the fine-earth fraction, or the material less than 2 millimeters in size. USDA Natural Resources Web Soil Survey 7/15/2015 Conservation Service National Cooperative Soil Survey Page 2 of 4 Physical Soil Properties---Albemarle County,Virginia TM61-P153A1 Erosion factor Tis an estimate of the maximum average annual rate of soil erosion by wind and/or water that can occur without affecting crop productivity over a sustained period. The rate is in tons per acre per year. Wind erodibility groups are made up of soils that have similar properties affecting their susceptibility to wind erosion in cultivated areas. The soils assigned to group 1 are the most susceptible to wind erosion, and those assigned to group 8 are the least susceptible. The groups are described in the"National Soil Survey Handbook." Wind erodibility index is a numerical value indicating the susceptibility of soil to wind erosion,or the tons per acre per year that can be expected to be lost to wind erosion. There is a close correlation between wind erosion and the texture of the surface layer,the size and durability of surface clods, rock fragments, organic matter, and a calcareous reaction. Soil moisture and frozen soil layers also influence wind erosion. Reference: United States Department of Agriculture,Natural Resources Conservation Service. National soil survey handbook,title 430-VI. 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