HomeMy WebLinkAboutSDP201500034 Study 2015-08-04 u \)\■°1)\
,V ,,,,„,
Thomas Jefferson Soil and Water
1.,......0 Conservation District
�,sa
"b9mari9 / 706 Forest St, SteG,Charlottesville, VA22903
Fi \\ J Tel: (434) 975-0224 Fax: (434) 975-1367
Ne'sun uvann& Web Page: www.tjswcd.orq
August 4, 2015
TO: Albemarle County Department of Community Development— Division of
Planning
RE: Soils Report for:
Site Review Committee
Federal Express and Retail Office Buildings — Phase 3
4
7 \IS /
z z
NI
zo
0900ZZb °ZOOM, 08661Zb 0466TZ6 00661Z4 09861Zb OZ8624 14 CI
M.6Z LZ o8L M,&LZ o8L N O
oo 0)
l4
a
1
'''.%. r >.
1 'W, 7 r'.‘,.-..;7:7V7,. 17, cn
0 CO U7
ii
i 80
a
p �, a�a N Z
rs /
■ 0,
co
x
E.
R Y. f0
y R 5 3
''----o„--:-:,-----:;,s,L,„,„.. ,:---- ,„ p: -/, . 8 1 .(24
ti + no, t .■ N
a
�
,# _ ". N
c-',..4,1,41t:PM:7',_-/ , s ., = ' .. --:`,,,,4N,,,„„, -.:...,,,,,,--„,::::- -s.---,i,,,_ z..:;i4 4 8
M,1612 o8L rr .. 214 - � -..,' ,.. ,. M,16 dZ oBL �'
0900ZZb OZOOZZ4 08662, 008[6717 �66TZb 0066TZb 098624 OZ86TZb 08L6 �1
z z
co
co
N
Nrrr
Lo cc.)
00
00 C m ° O C N N as
ap — C O C CU O C O
Lci N•O.N i0 .L.. V O ' d L 40 O
to 03
Z N co 0 0 ` CO CO a3 a3 I 3 C N CL
U C U U 0 as y'p L y 7 ° N of O C
d U W 0.O cn 0 a)'O a) E r u0i N _ Y N
Z a) C U ca O c.) CI)L a) >. N L O
ai 0 E m �vm0 a) a' cower Cl) co E Y. �
a) y Emma a) cu -0o — 2 Z El)<V o 0Eu)
Q o wE o n c n a� o a. y o 22 Fr 0
Q O U c0 ._-. L N N d C O.L N Cn C U Ts c C N C
LL/ O N a) p a) N
Q ? a u E ° U Us �' ° m _ � m n a .ID
w 3oc a�i 3 ,_ a) ,wom Y 0 0 o co 73 U. oL 3 c o m o E?..a) a)
_ ti c.� u'r 0 afl2 2� °_ y � Eo � c a ° � Es
Z p N ° co CL=.o 7 N U p as a) as O ° .0 a) >
0. C N•° O c U <a L as co a) a) n 0 4-L 2 as a)
O. E — Z 'o -0 a a0 � -o a) .0 aiE
Q E a� o a) a m� co Co co O c� N Q > aNi L O C .1)
as ° m > Z >a U� o= m oho
T 2
03 E - a)L — N N > L ). y n co N a) ca N E 0 a >.C
a) — O 'O L v C .N. O. >, a)t as co v) f0 0 —O ° CO p
? .° c c00~ ° ac) m ,u) 3'0 ° 40 < 0 `N m t c Tx- a
C" E '- Co 0E o� m Ec00-0 c o C aa) " 7 a) 0 -0C
_ 6 a) a) N a N '.73E 2 O a) p .N 2 < O.■ t0 L _O 0
o ` m e E w u) N `U)v u) U c � 0-0 cnn a) E o N p a w G.
N
L 0 C.0 0 o co ai a 0 o m.2 N�z r a .O 3 .o m � — a) E co E
H 5 W Env) dE co U 2c 'ao U I— -.E. (/)Cr) v) `o ON IL— c°>._ o
.co
E
rn
cu
2
0
7.� 0 O
000 cn
U 7 0 o
a)co u) r
`., ' 0 a)
Em ° at
a� .00
0 L o
A w 0 O
ca
kv c m o U
m
ca ) LL U r m c
n N .p co N . O O
a) O C C co = N 0 o co
.O a) a O p J y .0.. O O L z
co Q CO cn la E a) o cc x _a
.O c r `> 'U ca N 0: O la
co co > O cn 0 in O 0 g. 7 2 J o
Q c io
Z N a ° o
C
CD 3 It MI
W
J
CL CO
c
a O Q "rn w c o
m
n co
G a o c o
as
d Ja a n Co Z N m a
— ' a c c c m a 0
a.
O.
.C. N ' n °
m m as
ns 3 `M c Q ° d O ° co 'O ) N 4' t ° 0 O c >.,
N O C T,°3 >, 0 -0 as E) a) a) Y a y Y a)
d o .a .o ° ` m ° m m m m c y a) 0 m a) c O °an
< co (1) co 'Q m m U 0 0 0 J J 2 2 2 d 0_ cn cn cn m CO us
ro a y
c W v
❑ 01 .- ao 4 O0 > + -0 : �° a)
• y
a co ° o=
aa))
CL Z
R 0
0 N
C
ca O
2,C)
-wow Nor,
Soil Map—Albemarle County,Virginia 45B1-06-1B
Map Unit Legend
Albemarle County,Virginia(VA003)
Map Unit Symbol Map Unit Name Acres in AOI Percent of AOI
34C Glenelg loam,7 to 15 percent 0.0 0.2%
slopes
39C Hazel loam,7 to 15 percent 1.6 17.7%
slopes
39D Hazel loam,15 to 25 percent 0.2 2.1%
slopes
39E Hazel loam,25 to 45 percent 1.8 19.8%
slopes
88 Udorthents,loamy 5.0 54.7%
W Water 0.5 5.4%
Totals for Area of Interest 9.1 100.0%
USDA Natural Resources Web Soil Survey 8/4/2015
Conservation Service National Cooperative Soil Survey Page 3 of 3
Map Unit Description(Brief,Generated)---AlbePWfle County,Virginia '`✓ 45B1-06-1B
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: 34C—Glenelg loam, 7 to 15 percent slopes
Component: Glenelg (85%)
The Glenelg component makes up 85 percent of the map unit. Slopes are 7 to 15
percent. This component is on hillslopes, piedmonts. The parent material consists
of residuum weathered from mica schist. Depth to a root restrictive layer is greater
than 60 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
high. Shrink-swell potential is low. 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 3e. This soil does not meet hydric criteria.
Map Unit: 39C—Hazel loam, 7 to 15 percent slopes
USDA Natural Resources Web Soil Survey 8/4/2015
"'�� Conservation Service National Cooperative Soil Survey Page 1 of 3
Map Unit Description(Brief,Generated)---Alberriirle County,Virginia 45B1-06-1B
The Udorthents component makes up 85 percent of the map unit. Slopes are 2 to
25 percent.This component is on interfluves, uplands, uplands.The parent material
consists of residuum weathered from granite and gneiss. Depth to a root restrictive
layer is greater than 60 inches.Available water to a depth of 60 inches is very low.
Shrink-swell potential is low. This soil is not flooded. It is not ponded. There is no
zone of water saturation within a depth of 72 inches. This soil does not meet hydric
criteria.
Component: Wehadkee (3%)
Generated brief soil descriptions are created for major components.The Wehadkee
soil is a minor component.
Map Unit: W—Water
Component: Water(100%)
Generated brief soil descriptions are created for major soil components.The Water
is a miscellaneous area.
Data Source Information
Soil Survey Area: Albemarle County, Virginia
Survey Area Data: Version 10, Dec 11, 2013
L:Sr7AA Natural Resources Web Soil Survey 8/4/2015
"'a Conservation Service National Cooperative Soil Survey Page 3 of 3
Dwellings and Small Commercial Buildings---A'!b�ftiarle County,Virginia Noe 45B1-06-1B
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 8/4/2015
40.1111 Conservation Service National Cooperative Soil Survey Page 1 of 3
Dwellings and Small Commercial Buildings---Altienarle County,Virginia 45B1-06-1B
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
88—Udorthents,
loamy
Udorthents 85 Not rated Not rated Not rated
W—Water
Water 100 Not rated Not rated Not rated
Data Source Information
Soil Survey Area: Albemarle County, Virginia
Survey Area Data: Version 10, Dec 11, 2013
USDA Natural Resources Web Soil Survey 8/4/2015
Conservation Service National Cooperative Soil Survey Page 3 of 3
Roads and Streets,Shallow Excavations,and Spoils and Landscaping---Albemarle County, . _ 45B1-06-1B
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 8/4/2015
"om Conservation Service National Cooperative Soil Survey Page 1 of 3
Roads and Streets,Shallow Excavations,and L...ns and Landscaping---Albemarle County, 45B1-06-1B
Virginia
Roads and Streets,Shallow Excavations,and Lawns and Landscaping-Albemarle County,Virginia
Map symbol and soil Pct.of Local roads and streets Shallow excavations Lawns and landscaping
name map
unit Rating class and Value Rating class and Value Rating class and Value
limiting features limiting features limiting features
39C-Hazel loam,7 to
15 percent slopes
Hazel 80 Somewhat limited Very limited Very limited
Frost action 0.50 Depth to hard bedrock 1.00 Low exchange 1.00
capacity
Depth to hard bedrock 0.46 Slope 0.37 Depth to bedrock 0.46
Slope 0.37 Dusty 0.04 Slope 0.37
Unstable excavation 0.01 Dusty 0.04
walls
39D-Hazel loam, 15
to 25 percent slopes
Hazel 80 Very limited Very limited Very limited
Slope 1.00 Depth to hard bedrock 1.00 Slope 1.00
Frost action 0.50 Slope 1.00 Low exchange 0.75
capacity
Depth to hard bedrock 0.46 Dusty 0.04 Depth to bedrock 0.46
Unstable excavation 0.01 Dusty 0.04
walls
39E-Hazel loam,25
to 45 percent slopes
Hazel 80 Very limited Very limited Very limited
Slope 1.00 Depth to hard bedrock 1.00 Slope 1.00
Frost action 0.50 Slope 1.00 Low exchange 1.00
capacity
Depth to hard bedrock 0.46 Dusty 0.04 Depth to bedrock 0.46
Unstable excavation 0.01 Dusty 0.04
walls
88-Udorthents,
loamy
Udorthents 85 Not rated Not rated Not rated
W-Water
Water 100 Not rated Not rated Not rated
Data Source Information
Soil Survey Area: Albemarle County, Virginia
Survey Area Data: Version 10, Dec 11, 2013
ism Natural Resources Web Soil Survey 8/4/2015
-4111111- Conservation Service National Cooperative Soil Survey Page 3 of 3
Physical Soil Properties---Albemarle County,Virginia 45B1-06-1B
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 8/4/2015
Conservation Service National Cooperative Soil Survey Page 1 of 6
Physical Soil Properties---Albemarle County,Virginia 45B1-06-1B
Erosion factor T is 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. (http://soils.usda.gov)
USDA Natural Resources Web Soil Survey 8/4/2015
"'� Conservation Service National Cooperative Soil Survey Page 3 of 6
4
m
9
m
P 0 0
..c. .:0_
3c v co
m
co
d
d in to
P
c a
0
3 2 0)
a`)
to in
F
C O N N
t
N O Y N M CO N V) lh
O N M V. V. M a V.
Ww
M et N 01 er N
V
a3 U M M ch c'?
M C�)
O• a) a rO 0 u c) u-) r0 Ot0 6 t0
O E LL")N 00 00 al CV pO p0
O O O I O O O I I I
K i — O) O) 0) Cr! O) O)
C R d N N N N 0I N
a1 U
Q1 C C a t0 U In 6. LL')
7 J a)
g 0 0 0 I 0 0 0 I I I co
o
U m �, o Si 0 0 0 o mN
m an d _ = U)
R co `6 c o �? Si c o o co —'
a 0 0 0 I 0 0 0 I I 1 - o
>a) O
m▪ 'C U = a) Y Y Y N v 1 ' N
7 ' O O O O O 0 O O O
N .- R U E O -
o 3 LO co N N N N N CO
N ''Cl
O. co)L V E O O O O o O o O o O a O o O a 0 4 Ni:
W __ r r
•N N Y •N U i r It) t00 in t0 M to 0
o_ � � -°cu \� Nr Nr I Nr Nr I I I
0o co ao 0
T O
r
t6 M r M 4 4
o
a I 6 I I I
iii a !
co v v v I v v v I I I
- -
N E
-0 :-2 <8 c U
C o C
U
Y Y I v Y Y I I I m
c s 1 ` m
co d O N M h 0 N C)) co f 7 2
O O Or N M O Or N M I I Z U Lo
Q 0 N Tr
N 9 N ! O 0 n1�
4) E c N LO G),C, C - J':
a) N'0 6)•r C H co N C y t T y a)
o aN 2 80 _ fiEca3 °a' a) of .c a`�
t6 O co 67 i
o c M C a ti = M O G M 2 0 j
a)
cr) — co
To
U
N
T
_c
a
w
Soil Features---Albemarle County,Virginia 45B1-06-1B
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 8/4/2015
" Conservation Service National Cooperative Soil Survey Page 1 of 3
CO
0
CO
in r)
0
N
CO 0)
m
a
a
a)
N O
j
= w,
a7
O
to n
L O
�U
a
C
0
a)
Z
M
C
O
E N
O «
=MI C w
II
O 0
CO 0 o
coo °
Q d
m Ht
L f0 m
o
o) > Q) m «
ZQ reC
c
CU
(/) Z 0
0
a)
inv Z U
a)
(;)
a)
7
aD
a)
L
O