2018-11-19_REVISION - M1976056 ‎(6)‎

• Permit No: M1976056
• IBM Index Class Name: REVISION
• Doc Date: 11/19/2018
• Doc Name: Request For Amendment To Permit
• From: McAtee Construction
• To: DRMS
• Type & Sequence: AM2
• Email Name: PSH
• Email Name: MAC
• Media Type: D
• Archive: No

Custom Soil Resource Report
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.
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.
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