HomeMy WebLinkAbout990735.tiff Exhibit I - Soils Information
6.4.9
1) In consultation with the Soil Conservation Service or other qualified person, the
Operator/Applicant shall indicate on a map(in Exhibit C)or by a statement, the general type,
thickness and distribution of soil over the affected land. Such description will address suitability
of topsoil(or other material)for establishment and maintenance of plant growth. The above
information shall satisfy "completeness" requirements for purposes of determination of date of
filing.
EXISTING SOIL CONDITIONS
Exhibit C-2: Mining Plan Map, shows the type and extent of soils over the project site and relative
to the areas designated for resource recovery. Exhibit D -Mining Plan, describes general insitu
soil depths, soil salvage, stockpiling and stabilization of salvaged soil, and replacement depths.
Exhibit E- Reclamation Plan,references this Exhibit for additional information on Soils
Management, which follows under part 2), below.
Exhibit UJ-Soils and Vegetation Map,correlates soils to vegetation and topography. Additional
information on vegetation is detailed under the following Exhibit J -Vegetation Information.
Finally, information extracted from the 1980 Soil Series for Weld County, Southern Part, follows
as an addendum to this exhibit, and provides detailed information concerning the specific nature
and description of each soil encountered at the location.
12) If necessary, at its discretion, the Board may require additional information on soils or
other growth media to be stockpiled and used in revegetation to be submitted subsequent to the
ling and notification of"completeness"of the application.
COMMON GROUND
For purposes of this.project,this submittal will avoid lay terms such as topsoil, and utilize the well
established scientific nomenclature of the U.S. Natural Resources and Conservation Service
[NRCS, formerly, Soil Conservation Service]. For example: 'Topsoil' is commonly discussed as
if it were some homogeneous standard. In reality, soil is quite complex and can vary substantially
in quality and quantity from the surface to its general categorized depth of 60±inches.
For clarity, topsoil i.s generally regarded as the plow layer(upper six inches) on agricultural soils,
or the A-1 soil profile horizon otherwise. The solum, or soil, includes the topsoil plus all other
material above the parent rock(regolith)that meets the definition of soil. One soil differs from
another soil by its unique properties and characteristics (such as profile horizon development,
structure,texture, color,percent organic matter,chemical composition, etc.) and is identified as
such by soil scientists, and described in NRCS Soil Survey documents.
VEGETATION AND SOIL REMOVAL
Soil salvage will commence with the removal of the surface layer of soil to a depth of 4.0±to
10.0±inches [6.0±average]. Soils will be removed primarily with scrappers. To minimize the
undesirable effects of soil blowing and loss, and to avoid damage to the soil resource via
compaction, soil w ill be stripped wherever possible when soil is moist, and not dry or wet. Since
the soils of the upper terrace of this location have been irrigated, salvage will not attempt to salvage
soil below the upper foot in order to minimize removal of soils where salts may have accumulated
in the lower soil horizon(s).
EXHIBIT I - Soils Information 1
Colorado Division of Mineral s &Geology Regular Impact [112] Construction Material Permit
Sand Land, Inc. - Kurtz Resource Recovery & Development Project -January 1999
990735
Exhibit I - Soils Information
SOIL SALVAGE STOCKPILES
Once removed from its native location, soil will be windrowed along the perimeter of the area of
extraction and seeded with the reclamation seed mixture specified under Exhibit E-Table 1:
Reclamation Seed Mixture. This will provide an opportunity to gage the performance of the seed
mixture while attempting to provide a stabilizing cover of vegetation over the stockpile until it is
ready for replacement on finished slopes and affected lands remaining above the anticipated final
water level of the finished ponds. It should be noted that the final water level will fluctuate
seasonally with the groundwater.
Windrowed salvaged soil stockpiles will be graded such that side slopes are 3h:ly or flatter. This
will aid seeding efforts, while reducing the profile exposure of the stockpile to wind and water
erosion. To the extent possible, stockpiles will be oriented parallel to the prevailing Westerly
winds, and in a manner that will aid abatement of visual and noise impacts of on-going resource
recovery operations [refer to Exhibit D-Mining Plan].
SOIL TESTING, RECORDS, AND FOLLOW-UP
Soil horizonation study will occur as an ongoing part of the resource recovery and land reclamation
activities. Soil horizons will be analyzed and compared with publish NRCS Soil Survey data prior
to,or during, extraction activities. Differences in soil types, nature,and extent will be noted and
the soil map refined as applicable.
Insitu soils will be sampled across its different horizons as extraction activities progress across the
location. Sampling will utilize a hand auger and approved NRCS soil sample bags, and utilizing
recommended procedures. Testing will be conducted by the CSU Soil Laboratory in Ft. Collins,
Colorado. The tests will be used to monitor soil quality and suitability.
Salvaged soil volumes will be reported to areas requiring revegetation to assure adequate volumes
to area of affected land requiring revegetation. Soil tests and salvage reports will be provided to
the DMG at the time of the required DMG Annual Report.
SITE FOUNDATION AND STABILIZATION
Direct precipitation from short duration, high intensity rainstorm events, and wind, are the major
threats to soil stability at this location. Although the location is nearly a table,and although the
extraction will result in pits that cause water from direct precipitation to drain internally, additional
measures to assure site stability and protection of off-site areas will be made.
The measures taken to stabilize the soil stockpiles, as described above, should be adequate for
controlling erosion from wind and direct precipitation. Due to the flat topography,there is little
upland watershed that would impact the location. Additionally, the windrowed soil stockpiles will
also serve to reduce impacts of wind and precipitation of exposed areas undergoing extraction.
The greater threat of erosion will be to resoiled slopes pending establishment of vegetation during
reclamation. While some filling can be anticipated on unprotected areas during the initial phases of
reclamation, the conservation measures provided below should help to keep the potential for such
effects to a minimum.
Prior to resoiling,the foundation material that will underlie the soil will be sculpted to establish
initial soil stabilization features, and left rough to aid in resoil adhearance. Soil will be replaced
with scrappers, graded by dozers over the 18.0±inch minimum friable, or otherwise
EXHIBIT I - Soils Information 2
Colorado Division of Minerals &Geology Regular Impact [112] Construction Material Permit
Sand Land,Inc. - Kurtz Resource Recovery & Development Project -January 1999
Exhibit I - Soils Information
unconsolidated, subsoil. and tracked with the dozer in a manner that creates bars perpendicular to
the slope. An eighteen inch deep diversion will be placed above the intended 3h:l v or flatter pond
slopes, as established by concurrent grading during extraction activities. Water will be conveyed
by the diversion to an established grassed water way or other stable conveyance leading to the
pond bottom.
RESOILING TIMING
Resoiled areas will be allowed a minimum of three months to settle prior to seeding. Seeding will
follow in the fall [approximately 15 September to 1 November] as detailed under Exhibit E-
Reclamation Plan. Resoiling will occur when soil moisture is adequate to prevent blowing, yet dry
enough to prevent over-compaction. Part of the soil rebuilding process on the reconstituted soils
will be in establishing structure to the soils to facilitate plant-soil-water relationships. Overly
compacted soils will tend to limit soil structure development and create a poor seedbed for later
establishment.
STERILE HYBRID LIVE COVER CROP
Once applied to the surface, the new soils will be exposed to the raw forces of erosion until
adequate vegetative cover and root mass develops. Erosion requires both detachment and
transportation in order to occur. Running water,wind, and raindrop impact are the main forces of
erosion acting upon the soil. The use of a sterile hybrid live cover crop will aid in the stabilization
of the soil by allowing a quick vegetative cover to become established in advance of the native
grasses. The hybrid will also serve as an aid to reduce competition resulting from the
establishment and growth of unwanted pioneer species [weeds] on disturbed ground.
The attending reclamation seed mixture has a provision for the use of a sterile hybrid in lieu of
mulch. Mulch,even when crimped with specialized equipment,is subject to being blown off the
property,or reduced to an ineffective stubble. The hybrid will establish quickly but since it is
sterile,will not continue to compete with the emerging native grasses. After two to three years,it
will begin to die out as the natives increase their hold on the revegetated areas.
ORGANIC MATTER
Generally,the percent organic matter content [generally 1 - 3 % for native soils] of stockpiled soils
will fall over time. Depending upon soil testing and analysis of a specific soil stockpile,if soil
organic matter content falls below 1%, a minimum of four [4] tons of manure per acre will be
disced into the location where the indicated soil stockpile is reapplied to affected lands prior to
seeding. While this will add only 0.2 percent organic matter by weight to the total percent organic
matter of the soil in question, it should prove sufficient in increasing initial germination,
establishment, and survival of the applied seed mixture.
The applied organics will aid in the restructuring of the new soils by increasing the moisture and
fertility holding capacity of the upper profile while simultaneously facilitating root development of
the emerging grasses. As the roots of the emerging grasses develop and mature over time, the
resulting root mass will serve to add to the base percent organic matter content of the new soils
over time, thereby increasing the potential for long term survival and spread of the established
grasses. Soil testing will continue on the new soils to better gage the success of soil amendments
respective of the resulting vegetative cover.
FERTILIZATION
EXHIBIT I- Soils Information 3
Colorado Division of Minerals&Geology Regular Impact [112] Construction Material Permit
Sand Land, Inc. - Kurtz Resource Recovery & Development Project - January 1999
Exhibit I - Soils Information
The addition of fertilizer will also aid in the establishment, growth and survival of the emerging
grasses. Fertilizer will be applied to seeded areas at rates determined from soil tests of the
reapplied soils. Rates indicated under this submittal are for purposes of establishing a reasonable
warranty for the operation [refer to Exhibit L- Reclamation Cost Estimates.
In order to limit the establishment and growth of weeds,fertilizer will be applied at the time of
planting only if soil tests indicate the need for a starter fertilizer. To assure adequate soil fertility of
reclaimed lands, soil testing will be conducted periodically on revegetated lands until the lands in
question are released from the permit by the DMG.
WEED CONTROL
Weed control at the site will utilize non-chemical means, unless, due to weed morphology, or other
factors,circumstances require application of an approved herbicide. If chemical weed control is
utilized, it will be conducted in compliance with manufacturer's recommendations and in
conformance with applicable federal, state, or local laws. Where possible,pre-emergent weed
control chemicals will be utilized. Chemical application will be conducted or supervised by a
qualified operator, and coordinated with the Weld County Department of Public Works.
Weed control will focus upon prevention,principally through the establishment of a diverse
stabilizing cover of grasses, as described earlier. Regardless of control methodology, the intent of
mechanical and chemical methods will be to prevent weed species from reproducing vegetatively,
or by seed. In general,the idea is to aid the grasses in out competing weed species for plant
available water and nutrients in the new soils, until such a time that the grasses are fully established
over the applied areas, are dominant over the weeds, and capable of self regeneration. It should be
understood that some weeds will remain. Total eradication of weeds is unlikely under the best of
circumstances, and is not a reasonable expectation or likely outcome.
REVEGETATION
Treated reapplied soil will be seeded and a stabilizing cover of vegetation established as prescribed
above, and as detailed under Exhibit E-Reclamation Plan.
( rj
EXHIBIT I- Soils Information 4
Colorado Division of Mineral. s& Geology Regular Impact [112] Construction Material Permit
Sand Land, Inc. - Kurtz Resource Recovery &Development Project -January 1999
WELD COUNTY, COLORADO, SOUTHERN PART 7
brief description of the soil profile. In each description, The acreage and proportionate extent of each map unit
the principal hazards and limitations are indicated, and are given in table 4, and additional information on proper-
the management concerns and practices needed are ties, limitations, capabilities, and potentials for many soil
discussed. uses is given for each kind of soil in other tables in this
The map units on the detailed soil maps represent an survey. (See "Summary of tables.") Many of the terms
area on the landscape made up mostly of the soil or soils used in describing soils are defined in the Glossary.
for which the unit is named. Most of the delineations
shown on the detailed soil map are phases of soil series. Soil descriptions
Soils that have a profile that is almost alike make up a
soil series. Except for allowable differences in texture of 1—Altvan loam, 0 to 1 percent slopes. This is a deep,
the surface layer or of the underlying substratum, all the well drained soil on terraces at elevations of 4,500 to 4,900
soils of a series have major horizons that are similar in feet. It formed in old alluvium deposited by the major
composition, thickness, and arrangement in the profile. A rivers. Included in mapping are small areas of soils that
soil series commonly is named for a town or geographic show evidence of poor drainage. Also included are small,
feature near the place where a soil of that series was long and narrow areas of sand and gravel deposits.
first observed and mapped. Olney and Nunn, for example, Typically the surface layer of the Altvan soil is grayish
are names of two soil series. brown loam about 10 inches thick. The subsoil is brown
Soils of one series can differ in texture of the surface and light yellowish brown clay loam and sandy clay loam
layer or in the underlying substratum and in slope, ero- about 15 inches thick.The substratum is calcareous loamy
sion, stoniness, salinity, wetness, or other characteristics sand about 6 inches thick over gravelly sand.
that affect their use. On the basis of such differences, a Permeability and available water capacity are
soil series is divided into phases.The name of a soil phase moderate. The effective rooting depth is 20 to 40 inches.
commonly indicates a feature that affects use or manage- Surface runoff is slow,and the erosion hazard is low.
ment. For example, Olney fine sandy loam, I to 3 percent This soil is used almost entirely for irrigated crops. It
slopes,is one of several phases within the Olney series. is suited to all crops commonly grown in the area, includ-
Some map units are made up of two or more dominant ing corn, sugar beets, beans, alfalfa, small grain, potatoes,
kinds of soil. Such map units are called soil complexes and and onions. An example of a suitable cropping system is 3
undifferentiated groups. to 4 years of alfalfa followed by corn, corn for silage,
A soil complex consists of areas of two or more soils sugar beets, small grain, or beans. The high clay content
that are so intricately mixed or so small in size that they and the rapidly permeable substratum slightly restrict
cannot be shown separately on the soil map. Each area in- some crops.
eludes some of each of the two or more dominant soils, All methods of irrigation are suitable, but furrow ir-
and the pattern and proportion are somewhat similar in rigation is the most common (fig. 4). Proper irrigation
all areas. Midway-Shingle complex, 5 to 20 percent slopes, water management is essential. Barnyard manure and
is an example. commercial fertilizer are needed for top yields.
An undifferentiated group is made up of two or more Windbreaks and environmental plantings of trees and
soils that could be mapped individually but are mapped as shrubs commonly grown in the area are generally well
one unit because there is little value in separating them. suited to this soil. Cultivation to control competing
The pattern and proportion of the soils are not uniform. vegetation should be continued for as many years as
An area shown on the map has at least one of the domi-
nant (named) soils or may have all of them. Loup-Boel possible following planting.Trees that are best suited and
loamy sands, 0 to 3 percent slopes, is an undifferentiated have goad survival are Rocky Mountain juniper, eastern
group in this survey area. redcedar, ponderosa pine, Siberian elm, Russian-olive, and
Most map units include small, scattered areas of soils hackberry. The shrubs best suited are skunkbush sumac,
other than those that appear in the name of the map unit. lilac, Siberian peashrub,and American plum.
Some of these soils have properties that differ substan- This soil can produce habitat elements that are highly
Bally from those of the dominant soil or soils and thus suitable for openland wildlife, including pheasant, cotton-
could significantly affect use and management of the map tail, and mourning dove. Such crops as wheat, corn, and
unit. These soils are described in the description of each alfalfa provide suitable habitat for openland wildlife,
map unit. Some of the more unusual or strongly contrast- especially pheasant. Tree and shrub plantings and
ing soils that are included are identified by a special sym- undisturbed nesting cover would enhance openland wil-
bol on the soil map. dlife populations.
Most mapped areas include places that have little or no This Altvan soil has fair to good potential for urban
soil material and support little or no vegetation. Such and recreational development. The chief limiting soil fea-
places are called miscellaneous areas; they are delineated tures for urban development are the shrink-swell poten-
on the soil map and given descriptive names. Rock out- tial of the subsoil as it wets and dries and the rapid
crop is an example. Some of these areas are too small to permeability of the sand and gravel substratum. Septic
be delineated and are identified by a special symbol on tank absorption fields function properly, but in places the
the soil map. substratum does not contain enough fines to properly
8 SOIL SURVEY
filter the leachate. Sewage lagoons require sealing. 60 percent of the unit. Aquents, which have a lighter
Lawns, shrubs, and trees grow well. Capability subclass colored surface layer, make up about 35 percent. About 5
Its irrigated. percent is Aquepts and Bankard sandy loam.
2—Altvan loam, 1 to 3 percent slopes. This is a deep, These are deep, poorly drained soils that formed in
well drained soil on terraces at elevations of 4,500 to 4,900 recent alluvium. No one pedon is typical. Commonly the
feet. It formed in old alluvium deposited by the major soils have a mottled, mildly alkaline to moderately al-
rivers. Included in mapping are small areas of soils that kaline loamy or clayey surface layer and underlying
show evidence of poor drainage. Also included are small, material and are underlain by sand or sand and gravel
long and narrow areas of sand and gravel deposits. within 48 inches. In places they have a gleyed layer in the
Typically the surface layer of this Altvan soil is grayish underlying material.
brown loam about 10 inches thick. The subsoil is brown Most of the acreage is subject to flooding. The water
and light yellowish brown clay loam and sandy clay loam table is at or near the surface early in spring and recedes
about 14 inches thick.The substratum is calcareous loamy to as deep as 48 inches late in fall in some years.
sand about 5 inches thick over gravelly sand. These soils are used for rangeland and wildlife habitat.
Permeability and available water capacity are Some small areas have been reclaimed by major drainage
moderate. The effective rooting depth is 20 to 40 inches. and leveling and are used for irrigated crops.
Surface runoff is medium,and the erosion hazard is low. The potential native vegetation is dominated by alkali
This soil is used almost entirely for irrigated crops. It sacaton, switchgrass, and western wheatgrass. Saltgrass,
is suited to all crops commonly grown in the area, includ- sedge, rush, and alkali bluegrass are also prominent.
ing corn, sugar beets, beans, alfalfa, small grain, potatoes, Potential production ranges from 3,000 pounds per acre in
and onions. An example of a suitable cropping system is 3 favorable years to 2,000 pounds in unfavorable years. As
to 4 years of alfalfa followed by corn, corn for silage, range condition deteriorates, the switchgrass, alkali
sugar beets, small grain, or beans. Land leveling, ditch sacaton, and western wheatgrass decrease and saltgrass,
lining, and installing pipelines may be needed for proper sedge,and rush increase.
water application. Management of vegetation should be based on taking
All methods of irrigation are suitable, but furrow ir- half and leaving half of the total annual production. Seed-
rigation is the most common. Barnyard manure and com- ing is difficult and costly because numerous tillage prac-
mercial fertilizer are needed for top yields. tices are required to eliminate the saltgrass sod.
Windbreaks and environmental plantins of trees and
shrubs commonly grown in the area are generally well Switchgrass, western wheatgrass, alkali sacaton, tall
suited to this soil. Cultivation to control competing wheatgrass, and tall fescue are suitable for seeding. They
vegetation should be continued for as many years as can be seeded into a clean, firm seedbed. Seedbed
possible following planting. Trees that are best suited and preparation usually requires more than 1 year to
have good survival are Rocky Mountain juniper, eastern eliminate the saltgrass sod. A grass drill should be used.
redcedar, ponderosa pine, Siberian elm, Russian-olive, and Seeding early in spring has proven most successful.
hackberry. The shrubs best suited are skunkbush sumac, Wetland wildlife, especially waterfowl, utilize this unit.
lilac,Siberian peashrub,and American plum. The wetland plants provide nesting and protective cover,
This soil can produce habitat elements that are highly as well as some food. The nearby irrigated cropland,
suitable for openland wildlife including pheasant, cotton- where wildlife obtain much of their food and find protec-
tail, and mourning dove. Such crops as wheat, corn, and tive cover, makes this unit valuable to both wetland and
alfalfa provide suitable habitat for openland wildlife, openland wildlife.
especially pheasant. Tree and shrub plantings and Openland wildlife, especially pheasant, use this unit for
undisturbed nesting cover would enhance openland wil- cover and nesting. Deer find excellent cover in some
dlife populations. areas.
This Altvan soil has fair to good potential for urban These valuable wildlife areas should be protected from
and recreational development. The chief limiting soil fea- fire and fenced to prevent encroachment and overuse by
tures for urban development are the shrink-swell poten- livestock.They should not be drained.
tial of the subsoil as it wets and dries and the rapid These soils have good potential as a source of sand and
permeability of the sand and gravel substratum. Septic gravel. Capability subclass VIw; Salt Meadow range site.
tank absorption fields function properly, but in places the 4—Aquolls and Aquepts, flooded. This nearly level
substratum does not contain enough fines to properly map unit is in depressions in smooth plains and along the
filter the leachate. Sewage lagoons require sealing. bottoms of natural drainageways throughout the survey
Lawns, shrubs, and trees grow well. Capability subclass area. Aquolls, which have a dark colored surface layer,
Ile irrigated. make up about 55 percent of the unit. Aquepts, which
3—Aquolls and Aquents, gravelly substratum. This have a lighter colored surface layer, make up about 25
nearly level map unit is on bottom lands and flood plains percent. About 20 percent is soils that are well drained
of all the major streams in the survey area. Aquolls, and soils that have sandstone or shale within 48 inches of
which have a dark colored surface layer, make up about the surface.
WELD COUNTY, COLORADO, SOUTHERN PART 9
These are deep, poorly drained soils that formed in If summer fallowed in alternate years, this soil is well
recent alluvium. No one pedon is typical. Commonly the suited to winter wheat, barley, and sorghum. Winter
soils have a mottled, mildly to moderately alkaline loamy wheat is the principal crop. The predicted average yield is
or clayey surface layer and underlying material that ex- 33 bushels per acre. If the crop is winterkilled, spring
tends to a depth of 60 inches or more. In places they have wheat can he seeded. Generally precipitation is too low
a gleyed layer in the underlying material. for beneficial use of fertilizer.
Most of the acreage is subject to excessive runoff. The Stubble mulch farming, striperopping, and minimum til-
water table is at or near the surface in spring and during lage are needed to control soil blowing and water erosion.
the peak of the irrigation season. Terracing also may be needed to control water erosion.
These soils are used for rangeland and wildlife habitat. The potential native vegetation on this range site is
Some small areas are irrigated pasture. dominated by sand bluestem, sand reedgrass, and blue
The potential native vegetation is dominated by grama. Needleandthread, switchgrass, sideoats grama,
switchgrass, prairie cordgrass, saltgrass, alkali sacaton, and western wheatgrass are also prominent. Potential
big bluestem, indiangrass, western wheatgrass, slender Production ranges from 2,200 pounds per acre in favora-
wheatgrass, sedge, and rush. Cattails and bullrush grow ble years to 1,800 pounds in unfavorable years. As range
in the swampy spots associated with these range sites. condition deteriorates, the sand bluestem, sand reedgrass,
Potential production ranges from 4,000 pounds per acre in and switchgrass decrease and blue grama, sand dropseed,
favorable years to 3,000 pounds in unfavorable years. As and sand sage increase. Annual weeds and grasses invade
range condition deteriorates, the tall and mid grasses the site as range condition becomes poorer.
decrease, production drops, and saltgrass, sedge, and rush Management of vegetation should be based on taking
increase. The farming and irrigation in adjacent areas has half and leaving half of the total annual production. Seed-
increased the amount of salts on much of the acreage. ing is desirable if the range is in poor condition. Sand
Management of vegetation on this soil should be based bluestem, sand reedgrass, switchgrass, sideoats grama,
on taking half and leaving half of the total annual produc- blue grams, pubescent wheatgrass, and crested wheat-
tion. Switchgrass, big bluestem, indiangrass, western grass are suitable for seeding. The grass selected should
rm meet the seasonal requirements of livestock. It can be
wheatgrass, pubescent wheatgrass, inte ediate wheat-
seeded into a clean, firm sorghum stubble, or it can be
grass, tall wheatgrass, and tall fescue are suitable for
seeding. The plants selected should met the seasonal drilled into a firm prepared seedbed. Seeding early in
spring has proven most successful.
requirements of livestock. For successful seeding, a firm
prepared seedbed is needed. A grass drill should be used. ited t windbreaks and environmental plantings are generally
Seeding early in spring has proven most successful. Til- suited to this soil. Soil blowing, the principal hazard in
is needed to eliminate the undesirable vegetation. establishing trees and shrubs, can be controlled by cul-
lage Wetland wildlife, especially waterfowl, utilize this unit. vegetation
tivating only in the tree row and by leaving a strip of
vege between the rows. Supplemental irrigation
The wetland plants provide nesting and protective cover may be needed at the time of planting and during dry
as well as some food. The nearby irrigated cropland, periods.Trees that are best suited and have good survival
where wildlife obtain much of their food and find protec- are Rocky Mountain juniper, eastern redcedar, ponderosa
tive cover, makes this unit valuable to both wetland and pine, Siberian elm, Russian-olive, and hackberry. The
openland wildlife. shrubs best suited are skunkbush sumac, lilac, and Siberi-
Openland wildlife, especially pheasant, use this unit for an peashrub.
cover and nesting. Deer find excellent cover in some Wildlife is an important secondary use of this soil. The
areas. These valuable wildlife areas should be protected cropland areas provide favorable habitat for ring-necked
from fire and fenced to prevent encroachment and pheasant and mourning dove. Many nongame species can
overuse by livestock. They should not be drained. Capa- be attracted by establishing areas for nesting and escape
bility subclass VIw; Aquolls in Salt Meadow range site, cover. For pheasants, undisturbed nesting cover is essen-
. Aquepts in Wet Meadow range site. tial and should be included in plans for habitat develop-
5—Ascalon sandy loam, 1 to 3 percent slopes. This is ment. Rangeland wildlife, for example, the pronghorn an-
a deep, well drained soil on uplands at elevations of 4,600 telope, can be attracted by developing livestock watering
to 5,200 feet. It formed in alluvium. Included in mapping facilities, managing livestock grazing, and reseeding
are small areas of rock outcrop. where needed.
Typically the surface layer is brown sandy loam about Few areas of this Ascalon soil are in major growth and
10 inches thick. The subsoil is pale brown and yellowish urbanized centers. The shrink-swell potential of the sub-
brown sandy clay loam about 15 inches thick. The sub- soil as it wets and dries is the most limiting soil feature
stratum to a depth of 60 inches is calcareous fine sandy that must be considered in planning homesites and con-
loam. structing roads. Capability subclass IIIe nonirrigated;
Permeability is moderate. Available water capacity is Sandy Plains range site.
high. The effective rooting depth is 60 inches or more. 6—Ascalon sandy loam, 3 to 5 percent slopes. This is
Surface runoff is slow, and the erosion hazard is low. a deep, well drained soil on uplands at elevations of 4,600
12 SOIL SURVEY
This soil has good potential for urban and recreational Wildlife is an important secondary use of this soil. The
development. Increased population growth in the survey cropland areas provide favorable habitat for ring-necked
area has resulted in increased homesite construction. The pheasant and mourning dove. Many nongame species can
chief limiting soil features for urban development are the be attracted by establishing areas for nesting and escape
shrink-swell potential of the subsoil as it wets and dries cover. For pheasants, undisturbed nesting cover is essen-
and the limited ability of this soil to support a load. Septic tial and should be included in plans for habitat develop-
tank absorption fields function properly, but community ment, especially in areas of intensive agriculture. Range-
sewage systems should be provided if the population den- land wildlife, for example, deer and antelope, can be at-
sity increases. Because of the moderately rapid permea- tracted by managing livestock grazing and reseeding
bility of the substratum, sewage lagoons must be sealed. where needed.
Lawns, shrubs, and trees grow well. Capability subclass This soil is not suited to urban or recreational develop-
IIe irrigated. ment because of the flood hazard. Capability subclass
10—Bankard sandy loam, 0 to 3 percent slopes. This IVw irrigated, VIw nonirrigated; Sandy Bottom land
is a deep, somewhat excessively drained soil on flood range site.
plains at elevations of 4,450 to 5,000 feet. It formed in 11—Dresser sandy loam, 0 to I percent slopes. This is ,
stratified recent alluvium along streams and rivers. In- a deep, well drained soil on terraces at elevations of 4,700
eluded in mapping are numerous sand and gravel bars to 4,800 feet. It formed in alluvium deposited by the
and small areas of noncalcareous soils. South Platte River. Included in mapping are small areas
Typically the surface layer of this Bankard soil is of soils that have sand and gravelly sand in the lower
brown sandy loam about 4 inches thick. The underlying part of the substratum.
material to a depth of 60 inches is pale brown calcareous Typically the surface layer is
sand stratified with thin lenses of sandy loam, loam, and YP Y Y grayish brown sandy loam
fine gravel. about 11 inches thick. The subsoil is brown and yellowish
brown sandy clay loam about 19 inches thick. The sub-
Permeability is moderately rapid. Available water
capacity is low.The effective rooting depth is 60 inches or stratum to a depth of 60 inches is loamy sand.
more. Surface runoff is slow, and the erosion hazard is Permeability and available water capacity are
low. moderate. The effective rooting depth is 60 inches or
This soil is suited to limited cropping. It is sandy and more. Surface runoff is slow, and the erosion hazard is
subject to flooding. Pasture is the best use. Tall wheat- low'
grass, tall fescue, and annual sweetclover are some of the This soil is used almost entirely for irrigated crops. It
most suitable crops. Light, frequent irrigation by furrows is suited to all crops commonly grown in the area includ-
ing corn, sugar beets, beans, alfalfa, small grain, potatoes,
and flooding is best. Commercial fertilizer improves the
amount and value of forage produced. and onions. An example of a suitable cropping system is 3
to 4 years of alfalfa followed by corn, corn for silage,
The potential native vegetation is dominated by
grass, sugar beets, small grain, or beans. Few conservation prac-
switchgrass, indiangrass, sand bluestem, sand reed sideoats grama, needleandthread, and blue grama. Much tices are needed to maintain top yields.
of this range site includes other soils and vegetation in All methods of irrigation are suitable, but furrow ir-
such a complex pattern that it is difficult to map them rigation is the most common. Barnyard manure and com-
separately. Potential production ranges from 2,500 pounds mercial fertilizer are needed for top yields.
per acre in favorable years to 1,500 pounds in unfavorable Windbreaks and environmental plantings are generally
years. As range condition deteriorates, the tall and mid suited to this soil. Soil blowing, the principal hazard in
grasses decrease; blue grama, sand dropseed, and forbs establishing trees and shrubs, can be controlled by cul-
increase; and forage production drops. Undesirable weeds tivating only in the tree row and by leaving a strip of
and annuals invade the site as range condition becomes vegetation between the rows. Supplemental irrigation
poorer. may be needed at the time of planting and during dry
Management of vegetation should be based on taking periods.Trees that are best suited and have good survival
half and leaving half of the total annual production. Seed- are Rocky Mountain juniper, eastern redcedar, ponderosa
ing is desirable only in areas large enough to interseed or Pine, Siberian elm, Russian-olive, and hackberry. The -
to prepare a seedbed. Switchgrass, sand bluestem, sand shrubs best suited are skunkbush sumac, lilac, and Siberi-
reedgrass,sideoats grama, little bluestem, blue grama, pu- an peashrub.
bescent wheatgrass, and intermediate wheatgrass are Wildlife is an important secondary use of this soil.
suitable for seeding. This soil can be seeded by using an Ring-necked pheasant, mourning dove, and many non-
interseeder or a firm,clean sorghum stubble.A grass drill game species can be attracted by establishing areas for
is required. Seeding early in spring has proven most sue- nesting and escape cover. For pheasants, undisturbed
cessful. nesting cover is essential and should be included in plans
This soil is generally not suited to the establishment for habitat development, especially in areas of intensive
and growth of trees and shrubs. Onsite investigation is agriculture.
needed to determine feasibility and possible tree and This soil has good potential for urban and recreational
shrub species. development. Lawns, shrubs, and trees grow well. The
28
SOIL SURVEY
40—Nunn loam, I to 3 percent slopes. This is a deep, vegetation should be continued for as many years as
well drained soil on terraces at elevations of 4,550 to 5,000 possible following planting.Trees that are best suited and
feet. It formed in mixed alluvium. Included in mapping have good survival are Rocky Mountain juniper, eastern
are small, long and narrow areas of sand and gravel redcedar, ponderosa pine, Siberian elm, Russian-olive, and
deposits and small areas of soils that are subject to occa- hackberry. The shrubs best suited are skunkbush sumac,
sional flooding.Some leveled areas are also included. lilac, Siberian peashrub,and American plum.
Typically the surface layer of this Nunn soil is grayish Wildlife is an important secondary use of this soil. The
brown loam about 12 inches thick. The subsoil is light cropland areas provide favorable habitat for ring-necked
brownish gray clay loam about 12 inches thick. The upper pheasant and mourning dove. Many nongame species can
part of the substratum is light brownish gray clay loam. be attracted by establishing areas for nesting and escape
The lower part to a depth of 60 inches is brown sandy cover. For pheasants, undisturbed nesting cover is essen-
loam. tial and should be included in plans for habitat develop-
Permeability is moderately slow. Available water ment, especially in areas of intensive agriculture. Range-
capacity is high. The effective rooting depth is 60 inches land wildlife, for example, the pronghorn antelope, can be
or more. Surface runoff is medium, and the erosion attracted by developing livestock watering facilities,
hazard is low. managing livestock grazing,and reseeding where needed.
In irrigated areas this soil is suited to all crops com- This soil has fair to poor potential for urban develop-
monly grown in the area, including corn, sugar beets, ment. It has moderate to high shrink swell, low strength,
beans, alfalfa, small grain, potatoes, and onions. An exam- and moderately slow permeability. These features create
ple of a suitable cropping system is 3 to 4 years of alfalfa problems in dwelling and road construction. Those areas
followed by corn,corn for silage, sugar beets, small grain, that have loam or sandy loam in the lower part of the
or beans. Generally such characteristics as a high clay substratum are suitable for septic tank absorption fields
content or a rapidly permeable substratum slightly and foundations. Some areas of this soil are adjacent to
restrict some crops. streams and are subject to occasional flooding.The poten-
All methods of irrigation are suitable, but furrow ir- tial is fair for such recreational development as camp and
rigation is the most common. Proper irrigation water picnic areas and playgrounds. Capability subclass Ile ir-
management is essential. Barnyard manure and commer- rigated, IIIc nonirrigated; Loamy Plains range site.
cial fertilizer are needed for top yields. 41—Nunn clay loam, 0 to 1 percent slopes. is
Most nonirrigated areas are used for small grain. The deep, well drained soil on terraces and smooth plains at
soil is summer fallowed in alternate years. Winter wheat elevations of 4,550 to 5,150 feet. It formed in mixed allu-
is the principal crop. If the crop is winterkilled, spring vium and eolian deposits. Included in mapping are small,
wheat can be seeded. Generally precipitation is too low long and narrow areas of sand and gravel deposits and
for beneficial use of fertilizer. small areas of soils that are subject to occasional flooding.
Such practices as stubble mulch fanning, striperopping, Some small leveled areas are also included.
and minimum tillage are needed to control soil blowing Typically the surface layer of this Nunn soil is grayish
and water erosion. brown clay loam about 9 inches thick. The subsoil is light
The potential native vegetation is dominated by blue brownish gray clay loam about 14 inches thick. The upper
gram, Several mid grasses, such as western wheatgrass part of the substratum is clay loam. The lower part to a
and needleandthread, are also present. Potential produc- depth of 60 inches is sandy loam.
tion ranges from 1,600 pounds per acre in favorable years Permeability is moderately slow. Available water
to 1,000 pounds in unfavorable years. As range condition capacity is high. The effective rooting depth is 60 inches
deteriorates, the mid grasses decrease; blue grama, buf- or more. Surface runoff is slow, and the erosion hazard is
falograss, snakeweed, yucca, and fringed sage increase; low.
and forage production drops. Undesirable weeds and an- This soil is used almost entirely for irrigated crops. It
nuals invade the site as range condition becomes poorer. is suited to all crops commonly grown in the area, includ-
Management of vegetation on this soil should be based ing corn, sugar beets, beans, alfalfa, small grain, potatoes,
on taking half and leaving half of the total annual produc- and onions. An example of a suitable cropping system is 3
tion. Seeding is desirable if the range is in poor condition. to 4 years of alfalfa followed by corn, corn for silage,
Sideoats grama, little bluestem, western wheatgrass, blue sugar beets, small grain, or beans. Few conservation prac-
grama, pubescent wheatgrass,and crested wheatgrass are tices are needed to maintain top yields.
suitable for seeding. The grass selected should meet the All methods of irrigation are suitable, but furrow ir-
seasonal requirements of livestock. It can be seeded into rigation is the most common. Barnyard manure and com-
a clean, firm sorghum stubble, or it can be drilled into a mercial fertilizer are needed for top yields.
firm prepared seedbed. Seeding early in spring has Windbreaks and environmental plantings of trees and
proven most successful. shrubs commonly grown in the area are generally well
Windbreaks and environmental plantings of trees and suited to this soil. Cultivation to control competing
shrubs commonly grown in the area are generally well vegetation should be continued for as many years as
suited to this soil. Cultivation to control competing possible following planting. Trees that are best suited and
WELD COUNTY, COLORADO, SOUTHERN Pin,. 29
have good survival are Rocky Mountain juniper, eastern The potential native vegetation is dominated by
redcedar, ponderosa pine, Siberian elm, Russian-olive, and western wheatgrass and blue grama. Buffalograss is also
hackberry. The shrubs best suited are skunkbush sumac, present. Potential production ranges from 1,000 pounds
lilac, Siberian peashrub,and American plum. per acre in favorable years to 600 pounds in unfavorable
Wildlife is an important secondary use of this soil. The years. As range condition deteriorates, a blue grama-buf-
cropland areas provide favorable habitat for ring-necked falograss sod forms. Undesirable weeds and annuals in-
pheasant and mourning dove. Many nongame species can vade the site as range condition becomes poorer.
be attracted by establishing areas for nesting and escape Management of vegetation of this soil should be based
cover. For pheasants, undisturbed nesting cover is essen- on taking half and leaving half of the total annual produc-
tial and should be included in plans for habitat develop- tion. Range pitting can help in reducing runoff. Seeding is
ment,especially in areas of intensive agriculture. desirable if the range is in poor condition. Western
This soil has fair to poor potential for urban develop- wheatgrass, blue grama, sideoats grama, buffalograss, pu-
ment. It has moderate to high shrink swell, low strength, bescent wheatgrass, and crested wheatgrass are suitable
and moderately slow permeability. These features create for seeding. The grass selected should meet the seasonal
problems in dwelling and road construction. Those areas requirements of livestock. It can be seeded into a clean,
that have loam or sandy loam in the lower part of the firm sorghum stubble, or it can be drilled into a firm
substratum are suitable for septic tank absorption fields prepared seedbed. Seeding early in spring has proven
and foundations. Some areas of this soil are adjacent to most successful.
streams and are subject to occasional flooding.The poten- Windbreaks and environmental plantings are generally
tial is fair for such recreational development as camp and well suited to this soil. Cultivation to control competing
picnic areas and playgrounds. Capability class I irrigated. vegetation should be continued for as many years as
42—Nunn clay loam, I to 3 percent slopes. This is a possible following planting.Trees that are best suited and
deep, well drained soil on terraces and smooth plains at have good survival are Rocky Mountain juniper, eastern
elevations of 4,550 to 5,150 feet. It formed in mixed allu- redcedar, ponderosa pine, Siberian elm, Russian-olive, and
vium and eolian deposits. Included in mapping are small, hackberry. The shrubs best suited are skunkbush sumac,
long and narrow areas of sand and gravel deposits and lilac, Siberian peashrub,and American plum.
small areas of soils that are subject to occasional flooding. Wildlife is an important secondary use of this soil. The
Some leveled areas are also included. cropland areas provide favorable habitat for ring-necked
Typically the surface layer of this Nunn soil is grayish pheasant and mourning dove. Many nongame species can
brown clay loam aobut 9 inches thick. The subsoil is light be attracted by establishing areas for nesting and escape
brownish gray clay loam about 14 inches thick.The upper cover. For pheasants, undisturbed nesting cover is essen-
part of the substratum is light brownish gray clay loam. tial and should be included in plans for habitat develop-
The lower part to a depth of 60 inches is brown sandy ment, especially in areas of intensive agriculture. Range-
loam. land wildlife, for example, the pronghorn antelope, can be
Permeability is moderately slow. Available water attracted by developing livestock watering facilities,
capacity is high. The effective rooting depth is 60 inches managing livestock grazing,and reseeding where needed.
or more. Surface runoff is medium, and the erosion This soil has fair to poor potential for urban develop-
hazard is low. ment. It has moderate to high shrink swell, low strength,
In irrigated areas this soil is suited to all crops com- and moderately slow permeability. These features create
monly grown in the area, including corn, sugar beets, problems in dwelling and road construction. Those areas
beans, alfalfa, small grain,potatoes, and onions. An exam- that have loam or sandy loam in the lower part of the
ple of a suitable cropping system is 3 to 4 years of alfalfa substratum are suitable for septic tank absorption fields
followed by corn,corn for silage, sugar beets,small grain, and foundations. Some areas of this soil are adjacent to
or beans. Generally such characteristics as the high clay streams and are subject to occasional flooding.The poten-
content or the rapidly permeable substratum slightly tial is fair for such recreational development as camp and
restrict some crops. picnic areas and playgrounds. Capability subclass ale ir-
All methods of irrigation are suitable, but furrow ir- rigated, Illc nonirrigated; Clayey Plains range site.
rigation is the most common. Proper irrigation water 43—Nunn loamy sand, 0 to 1 percent slopes. This is a
management is essential. Barnyard manure and commer- deep, well drained soil on terraces at elevations of 4,700
cial fertilizer are needed for top yields. to 4,900 feet. It formed in alluvium along Box Elder
In nonirrigated areas most of the acreage is in small Creek. Included in mapping are small areas of soils that
grain and it is summer fallowed in alternate years. have a loamy subsoil and small areas of soils that are sub-
Winter wheat is the principal crop. The predicted average ject to rare flooding.
yield is 33 bushels per acre. If the crop is winterkilled, Typically the surface layer of this Nunn soil is brown
spring wheat can be seeded. Generally precipitation is too loamy sand overburden about 9 inches thick. The subsoil
low for beneficial use of fertilizer. is dark to very dark grayish brown clay loam about 21
Stubble mulch farming, striperopping, and minimum til- inches thick. The substratum to a depth of 60 inches is
lage are needed to control soil blowing and water erosion. loamy very fine sand, loamy sand,or sand.
66 SOIL SURVEY
thought to typify the great group. An example is Typic 6.3ca-9 to 14 inches; very, pale brown (IDYR 7/3) silt loam, brown
Haplaquents. (10YR 5/3) moist; moderate to weak coarse prismatic structure
FAMILY. Families are established within a subgroup parting to moderate to weak medium subangular blocky; very hard,
on the basis of similar physical and chemical properties friable; few thin clay films on faces of reds; some visible lime in
medium soft masses; calcareous; moderately alkaline; gradual ir-
that affect management. Among the properties con- regular boundary.
sidered in horizons of major biological activity below plow Cca-14 to 60 inches; very pale brown (10YR 7/3) silt loam, yellowish
depth are particle-size distribution, mineral content, tem- brown(10YR 5/4)moist; massive;slightly hard, very friable; some
perature regime, thickness of the soil penetrable by roots, visible lime in fine filaments or threads; calcareous; moderately al-
kaline.
consistence, moisture equivalent, soil slope, and per- Thickness of the solum ranges from 8 to 15 inches.Depth to free car-
manent cracks. A family name consists of the name of a
subgroup and a series of adjectives. The adjectives are bonates ranges fhroams 5v altou etoo inches.
the class names for the soil properties used as family dif- 2 or3.The B2t horizon is commonly clay 6 dry to ld 3 oam r 4 moist
that is 30 to 40 percent
ferentiae. An example is fine-loamy, mixed, nonacid, clay.The C horizon is commonly silt loam or loam.
mesic,Typic Haplaquents. -
SERIES. The series consists of soils that formed in a Altvan series
particular kind of material and have horizons that, except
for texture of the surface soil or of the underlying sub- The Altvan series consists of deep, well drained soils
stratum, are similar in differentiating characteristics and that formed in material weathered from loamy alluvium
in arrangement in the soil profile. Among these charac- underlain by sand and gravel. Altvan soils are on ter-
teristics are color, texture, structure, reaction, con- races. Slopes are 0 to 3 percent.
Altvan soils are similar to the Ascalon, Dacono, and sistence,and mineral and chemical composition.
Nunn soils and are near the Colombo soils. Ascalon and
Colombo soils lack a sand and gravel C horizon between
Soil series and morphology 20 and 40 inches. Dacono and Nunn soils average more
than 35 percent clay in the B horizon.
In this section, each soil series recognized in the survey Typical pedon of Altvan loam, 0 to 1 percent slopes,
area is described in detail. The descriptions are arranged 1,850 feet north and 2,450 feet west of southeast corner
in alphabetic order by series name. sec.27,T.6 N., R.67 W.
Characteristics of the soil and the material in which it
Ap—°to 10 inches;grayish brown(10YR 5/2)loam,dark brown(10YR
formed are discussed for each series. The soil is then
compared to similar soils and to nearby soils of other se- 3/3) moist; weak fine granular structure; hard, friable; 3 percent
gravel;calcareous;mildly alkaline;abrupt smooth boundary.
ries. Then a pedon, a small three-dimensional area of soil B21-10 to 20 inches; brown (10YR 5/3)clay loam, dark brown(IDYR
that is typical of the soil series in the survey area, is 4/3) moist; moderate coarse prismatic structure parting to weak
medium subangular blocky; very hard, firm; few thin clay fdms on described. The detailed descriptions of each soil horizon
follow standards in the Soil Manual faces of pads; 3 percent gravel; noncalcareous; mildly alkaline;
Survey (4). Unless abrupt wavy boundary.
otherwise noted,colors described are for moist soil. Baca-20 to 25 inches; light yellowish brown (IDYR 6/4) sandy clay
Following the pedon description is the range of impor- loam,dark yellowish brown(ZOYR 4/4)moist;weak coarse prismatic
structure;hard,friable;very few thin clay films on faces of peels;2
tant characteristics of the soil series in this survey area.
Phases, or map units, of each soil series are described in percent gravel;some visible lime in fine seams and threads;calcare-
ous;moderately alkaline;clear smooth boundary.
the section "Soil maps for detailed planning." C1-25 to 31 inches;pale brown(IDYR 6/3)loamy sand,grayish brown
(IDYR 6/2) moist; massive; slightly hard, very friable; 10 percent
Adena series gravel;calcareous;moderately alkaline;clear smooth boundary.
IIC2-31 to 60 inches; pale brown (10YR 6/3) gravelly sand, brown
The Adena series consists of deep, well drained soil (IDYR 5/3) moist; single grained; loose; 30 percent gravel; calcare-
that formed in calcareous eolian deposits. Adena soils are ous;mildly alkaline.
on plains. Slopes are 3 to 9 percent. Thickness of the solum ranges from 16 to 28 inches.Coarse fragments .
make up less than 10 percent of the solum. Depth to free carbonates
Adena soils are near Colby and Weld soils. Colby soils
lack a 13 horizon. Weld soils have a dark colored surface ranges from 16 to 24 inches.Depth to contrasting material ranges 20 to
40 inches.
layer. The A horizon has value of 4 or 5 dry and 2 or 3 moist and chroma of
Typical pedon of Adena loam in an area of Colby-Adena 2 or 3.The 62t horizon is commonly clay loam or sandy clay loam that is
loams, 3 to 9 percent slopes, 2,150 feet south and 950 feet 20 to 35 percent clay.
west of northeast corner sec.23,T. 1 N., It.61 W.
Ascalon series
Ap—O to 6 inches; brown (10YR 5/3) loam, dark brown (10YR 4/3)
moist;moderate fine granular structure;hard,very friable;neutral; The Ascalon series consists of deep, well drained soils
abrupt smooth boundary. that formed in alluvium. Ascalon soils are on upland hills
R2t-6 to 9 inches;brown(lOYR 5/3)clay loam,dark brown(IDYR 4/3)
moist;strong medium to fine prismatic structure parting to strong and old terraces. Slopes are 0 to 9 percent.
medium to fine angular blocky;very hard,firm;common moderately Ascalon soils are similar to the Altvan and Nunn soils
thick clay films on faces of pads;neutral;clear smooth boundary. and are near the Olney and Vona soils. Altvan soils have
WELD COUNTY, COLORADO, SOUTIIEItN PA 71
percent weathered shale chips; calcareous; moderately alkaline; Mt-9 to 19 inches; light brownish gray (10YR 6/2) heavy clay loam,
gradual wavy boundary. dark grayish brown (IOY R 4/2) moist; moderate fine prismatic
C2r-13 inches;calcareous clayey shale. structure parting to moderate fine subangular blocky; very hard,
rcall these soils have free carbonates at the surface. Depth to firm;common moderately thick clay films on faces of peds; noncal-
Typ YP careous;mildly alkaline;clear wavy boundary.
shale ranges from 10 to 20 inches. 53-19 to 23 inches; light brownish gray (IOYR 6/2) heavy clay loam,
The A horizon has hue of 10YR or 2.5Y,value of 5 or 6 dry and 3 or 4 dark grayish brown(IOYR 4/2) moist; moderate medium prismatic
moist,and chrome of 2 or 4.The C horizon has hue of 10YR or 2.5Y. It structure parting to weak fine subangular blocky;hard,friable;cad-
is commonly clay that is 40 to 45 percent clay. careous;mildly alkaline;clear wavy boundary.
Clca-23 to 29 inches; light brownish gray (10YR 6/2)clay loam,dark
Nelson series grayish brown (10YR 4/2) moist; weak coarse prismatic structure
parting to weak medium subangular blocky;slightly hard,very fria-
- The Nelson series consists of moderately deep, well ble; some visible lime in fine seams and filaments; calcareous; .
drained soils that formed in residuum from soft calcare- moderately alkaline;clear wavy boundary.
C2ca-29 to 60 inches;brown(IOYR 5/3)sandy loam,dark brown(10YRous sandstone. Nelson soils are on plains. Slopes are 0 to
4/3)moist;weak coarse subangular blocky structure;soft,very fria-
9 percent. ble; some visible lime in fine filaments; calcareous; moderately al-
Nelson soils are similar to Kim, Otero, Tassel, and kaline.
Thedalund soils and are near the Olney soils. Kim, Otero Thickness of the solum ranges from 17 to 33 inches.Coarse fragments
and Olney soils are deep. Tassel soils have sandstone make up as much as 10 percent of the solum. Depth to free carbonates
between 10 and 20 inches. Thedalund soils are more than ranges from 12 to 25 inches.
18 percent clay in the C horizon. The A horizon has hue of IOYR or 2.5Y,value of 4 or 5 dry and 2 or 3
Typical pedon of Nelson fine sandy loam,0 to 3 percent moist, and chroma of 2 or 3. It is clay loam, loam,or loamy sand.The
slopes, 2,000 feet south and 2,450 feet east of northwest 62t horizon is commonly heavy clay loam that is 35 to 40 percent clay.
corner sec. 17,T.6 N., R.66 W.
Olney series
Ap-0 to 9 inches;light brownish gray(10YR 6/2)fine sandy loam,dark
grayish brown (IOYR 4/2) moist; weak medium subangular blocky The Olney series consists of deep, well drained soils
structure parting to moderate fine granular,slightly hard,very fria- that formed in alluvium. Olney soils are on plains. Slopes
ble;calcareous;moderately alkaline;abrupt smooth boundary. are 0 to 5 percent.
Clca-9 to 30 inches;light olive brown(2.5Y 5/4)fine sandy loam,olive
brown (2.5Y 4/4) moist; massive; hard, very friable; some visible Olney soils are similar to the Fort Collins and Vona
lime occuring as concretions and in fine seams and filaments; cal. soils and are near the Kim, Nelson, Otero, and Thedalund
careous;moderately alkaline;gradual wavy boundary. soils. Fort Collins soils are less than 35 percent fine and
C2r-30 inches;soft calcareous sandstone. coarser sand in the B horizon. Vona soils are less than 18
Typically these soils have free carbonates at the surface. Depth to Percent clay in the B horizon. Nelson and Thedalund soils
soft sandstone ranges from 20 to 40 inches. Content of rock fragments have sandstone and shale between 20 and 40 inches.
ranges from 0 to 10 pen:ent. Typical pedon of Olney fine sandy loam, 0 to 1 percent
The A horizon has hue of IOYR or 2.5Y,value of 5 or 6 dry and 3 or 4 slopes, 1,320 feet north and 284 feet east of southwest
moist,and chroma of 2 or 3.The C horizon has hue of 10YR or 2.5Y. It corner sec.28,T.6 N., R. 66 W.
is fine sandy loam or sandy loam
Ap-0 to 10 inches; grayish brown (10YR 5/2) fine sandy loam, dark
Nunn series grayish brown (10YR 4/2) moist; weak fine granular structure;
slightly hard, very friable; noncalcareous; mildly alkaline; abrupt
The Nunn series consists of deep, well drained soils smooth boundary.
that formed in mixed alluvium and eolian deposits. Nunn B2t-10 to 20 inches;yellowish brown(10YR 5/4)sandy clay loam,dark
soils are on terraces, alluvial fans, and smooth plains. yellowish brown (IOYR 4/4) moist; moderate medium prismatic
structure parting to moderate fine subangular blocky;hard,friable;
Slopes are 0 to 3 percent. common moderately thick clay films on faces of pods;noncalcareous;
Nunn soils are similar to the Altvan and Dacono soils mildly alkaline;clear wavy boundary.
and are near the Colombo, Fort Collins, Haverson, and B3ca-20 to 25 inches; very pale brown (IOYR 7/3) sandy clay loam,
Weld soils. Altvan and Dacono soils have a sand and brown (IOYR 5/3) moist; moderate coarse prismatic structure;
slightly hard, very friable; some visible lime occuring in fine to
gravel C horizon at a depth of 20 to 40 inches. Colombo medium seams and soft masses; calcareous; moderately alkaline;
and Haverson soils lack a B horizon. Fort Collins soils are gradual smooth boundary.
less than 35 percent clay in the B horizon.Weld soils have Cca-25 to 60 inches;very pale brown(10YR 7/3)fine sandy loam,pale
an abrupt textural boundary between the A and B brown(10YR 6/3)moist; weak coarse subangular blocky structure;
horizons, slightly hard, very friable; some visible lime in fine to medium
threads and seams;calcareous;moderately alkaline.
Typical pedon of Nunn clay loam, 0 to 1 percent slopes,
400 feet north and 1,040 feet east of southwest corner Thickness of the solum ranges from 17 to 30 inches.Coarse fragments
sec.22,T.6 N., R.66 W. make up as much as 15 percent of the solum. Depth to free carbonates
ranges from 10 to 24 inches.
Ap-0 to 9 inches;grayish brown(IOYR 5/2)clay loam;very dark gray- The A horizon has hue of 10YR or 2.5Y,value of 5 or 6 dry and 3 to 5
ish brown (IOYR 3/2) moist; moderate fine granular structure; moist,and chroma of 2 or 3. It is fine sandy loam or loamy sand.The
slightly hard, friable; noncalcareous; mildly alkaline; clear smooth 132t horizon is commonly sandy clay loam,but clay content ranges from
boundary. 18 to 30 percent.
WELD COUNTY, COLORADO, SOUTHERN PART 129
TABLE 13.--PHYSICAL AND CHEMICAL PROPERTIES OF SOILS
[The symbol < means less than; > means greater then. The erosion tolerance factor (T) is for the entire
profile. Absence of an entry means data were not available or were not estimated]
Risk of corrosion Erosion Wind
Soil name and Depth Permea- Available Soil Salinity Shrink- factors erodi-
map symbol bility water reaction swell Uncoated ;Concrete bility
capacity potential steel K T group
In In/hr In/in i'" r9mhos/cm - --"r'"-"------r -r----
1, 2 0-10 0.6-2.0 0.20-0.24 6.6-7.8 --- Low Moderate Low 0.24 3 5
Altvan '03-25 0.6-2.0 0.15-0.17 7.4-8.4 <2 Moderate Moderate Low 0.28
25-60 >20 0.02-0.04 7.4-9.0 <2 Low Moderate Low 0.10
3':
Aquolls 0-48 --- --- --- ---
48-60 >20 0.04-0.06 7.4-8.4 2-16 Low High Moderate ---
Aquents 0-48,
48-60 >20 0.04-0.06 7.4-8.4 2-16 Low High Moderate ---
4.:
Aquolls 0-60
Aquepts 0-60 --- --- --- ---
5, 6, 7, 8, 9 0-8 0.6-6.0 0.11-0.16 6.6-7.8 <2 Low Low Low 0.17 5 3
Ascalon 8-18 0.6-2.0 0.13-0.15 6.6-7.8 <2 Moderate Moderate Low 0.24
18-60 0.6-6.0 0.11-0.15 7.9-8.4 <2 Low Moderate Low 0.24
10 0-4 2.0-6.0 0.09-0.12 7.4-8.4 <2 Low Moderate Low 0.10 > 3
Bankard 4-60 6.0-20 0.05-0.08 7.4-8.4 <2 Low Moderate Low 0.10
11, 12 0-16 0.6-6.0 0.11-0.13 6.1-7.3 --- Low Low Low 0.10 5 2
Bresser 16-25 0.6-2.0 0.15-0.18 6.6-7.3 --- Low Moderate Low 0.15
25-30 0.6-6.0 0.10-0.13 6.6-7.3 --- Low Low Low 0.In
30-60 2.0-20 0.05-0.08 6.6-7.3 --- Low Low Low 0.10
13 0-9 2.0-6.0 0.07-0.09 7.4-8.4 <2 Low Moderate Low 0.10 5 8
Cascajo 9-31 6.0-20 0.05-0.08 7.4-8.4 <2 Low Moderate Low 0.10
31-60 6.0-20 0.05-0.06 7.4-8.4 <2 Low Moderate Low 0.10
14, 15, 16, 17 0-7 0.6-2.0 0.20-0.24 6.6-8.4 <2 Low Moderate Low 0.37 5 4L
Colby 7-60 0.6-2.0 0.17-0.22 7.4-8.4 <2 Low Moderate Low 0.37
18•:
Colby 0-7 0.6-2.0 0.20-0.24 6.6-8.4 <2 Low Moderate Low 0.37 5 4L
7-60 0.6-2.0 0.17-0.22 7.4-8.4 <2 Low Moderate Low 0.37
Adana 0-6 0.6-2.0 0.18-0.21 6.6-7.8 <2 Low Moderate Low 0.37 5 5
6-9 0.06-0.2 0.16-0.18 6.6-7.8 <2 High High Low 0.24
9-60 0.6-2.0 0.16-0.18 7.4-8.4 <2 Low High Low 0.32
19, 20 0-14 0.6-2.0 0.14-0.18 7.4-8.4 <2 Low High Low 0.32 5 5
Colombo 14-21 0.6-2.0 0.14-0.16 7.4-8.4 <2 Moderate High Low 0.28
21-60 0.6-2.0 0.14-0.16 7.4-8.4 <2 Low High Low 0.28
21, 22 0-12 0.2-0.6 0.19-0.21 6.6-7.8 <2 Moderate Moderate Low 0.24 3 5
Dacono 12-21 0.2-0.6 0.15-0.21 7.4-8.4 <2 High High Low - 0.24
_
21-27 0.2-2.0 0.13-0.18 7.4-8.4 <2 Moderate High Low 0.15
27-60 >20 0.03-0.05 7.4-8.4 <2 Low High Low - 0.10
23, 24 0-7 0.6-2.0 0.16-0.20 6.6-7.8 <2 Low Moderate Low 0.20 5 6
Fort Collins 7-11 0.6-2.0 0.16-0.18 7.4-7.8 <2 Moderate Moderate Low 0.70
11-60 0.6-2.0 0.16-0.18 7.4-8.4 <2 Low High Low - 0.20
25, 26 i 0-4 0.6-2.0 0.14-0.18 6.6-8.4 <8 Low High Low 0.28 5 4L
Haverson 4-60 0.6-2.0 0.14-0.18 7.4-8.4 <8 Low High Low 0.78
27, 28 i 0-60 0.06-0.6 0.12-0.17 7.9-9.0 <8 High High high 0.28 5 4
Heldt
See footnote at end of table.
130 SOIL SURVEY
TABLE 13.--PHYSICAL AND CHEMICAL PROPERTIES OF SOILS--Continued
r
Soil name and Depth Permea-a- Available Soil Salinity r Shrink- Risk of rosion Erosion Wind
map symbol bility water reactionfactors bility
capacity swell Uncoated Concrete ; -T- —
In In/hr R" rMmhoshcni_potential
Cen ti al steel bility
In/in --------- -- _._ _ w T group
29, 30 0-12 2.0-20 0.11-0.15 6.6-7.8 <2 Low 4 5 3-
Julesburg 12-27 2.0-20 0.11-0.15 6.6-7.8 <2 Moderate Low 0.24 3
27-60 >6.0 0.05-0. 13 6.6-7.8 <2 Low Moderate Low 0.20
Moderate Low 0.20
31, 32, 33, 34 0-12 0.6-2.0 0.16-0.18 7.9-8.4 <2 Low Moderate Low 0.32 5 41.
Kim 12-60 0.6-2.0 0.15-0.17 7.9-8.4 <2 Low
Moderate Low 0.32
35•:
Loup 0-16 6.0-20 0.10-0.14 6.6-8.4 <2
Low High Low 0.17 5 2
16-60 6.0-20 0.06-0.08
7.4-8.4 <2 Low High Low 0.17 _
Boel 0-14 6.0-20 0.10-0.12 6.6-8.4 <2 Low
14-60 6.0-20 0.05-0.07 6.6-8.4 <2 Low Highh Low 0.17 5 2
B Low 0.17
Midway 0-13 0.06-0.2 0.12-0.17 7.9-9.0 2_
13 8 High High Low 0.43 1 4
Shingle 0-6 0.6-2.0 0.16-0.18 7.4-9.0 <2 Low
6-18 0.6-2.0 0.16-0.21 7.9-9.0 <2 Moderate HHighh Low 0.32 7 41.
18 ___ ___ g Low 0.49
37, 38 0-9 2.0-6.0 0.13-0.15 7.9-8.4 <2 Low 3
Nelson 9-30 2.0-6.0 0.11-0.13 7.9-8.4 <2 Low High Low 0.20 2
High Low 0.'0
30
39, 40, 41, 42 0-9 0.2-2.0 0.15-0.20 6.6-7.8 <2 Moderate Moderate Low 0.24 Nunn 9-29 0.06-0.6 0.15-0.18 7.4-8.4 <2 5 6
29-60 0.2-2.0 0.10-0.18 7.4-8.4 High High Low 0.28
<2 Moderate High Low 7,24
43 0-9 2.0-6.0 0.10-0.14 6.6-7.8 <2 Low
Nunn 9-29 0.06-0.6 0.15-0.18 Moderate Low 0.18 5
7.4-8.4 <2 High 3
29-60 0.2-2.0 0.10-0.18 7.4-8.4 <2 Moderate High Low 0.28
High Low 9,711
44, 45 0-10 6.0-20 0.06-0.10 6.6-7.8 <2 Low Low Low 0.17 5 2
Olney 10-20 0.6-2.0 0.13-0.15 6.6-7.8 <2 Moderate High Low 0.74
20-25 0.6-6.0 0.11-0.15 7.9-8.4 <2 Low High Low 0.74
25-60 2.0-6.0 0.06-0.13 7.9-8.4 <2 Low High Low 0.20
46, 47, 48 0-10 0.6-6.0 0.11-0.15 6.6-7.8 <2 Low Moderate Low 0.20 5 3
Olney 10-20 0.6-2.0 0.13-0.15 6.6-7.8 <2 Moderate High Low 0.74
20-25 0.6-6.0 0.11-0.15 7.9-8.4 <2 Low High Low 0.29
25-60 2.0-6.0 0.06-0.13 7.9-8.4 <2 Low High Low 0.70
49 0-22 6.0-20 0.05-0.08 6.6-7.3 --- Low Low Low 0.10 5 1
Osgood 22-34 2.0-6.0 0.10-0.13 6.6-7.3 --- Low 34-60 6.0-20 0.06-0.08 6.6-8.4 <2 Low Low Low 0.17
Moderate Low 0. 10
50, 51, 52, 53 0-12 6.0-20 0.09-0.13 7.4-8.4 <2 Low High Low 0.10 5 2
Otero 12-60 6.0-20 0.08-0.12 7.4-8.4 <4 Low High Low 0.10
54, 55 0-20 6.6-2.0 0.16-0.18 6.6-7.3 --- Low Moderate Low 0.20 5 5
Paoli 20-25 >6.0 0.14-0.17 7.4-7.8 <2 Low High Low 0.20
25-60 >6.0 0.12-0.14 7.4-8.4 <2 Low High Low 0.20
56, 57 0-9 0.2_0.6 0.17-0.21 6.6-7.8 <2 Moderate High Low 0.37 3 6
Renohill 9-32 0.06-0.2 0.14-0.16 6.6-8.4 <2 High High Low 0.32
32 --- ___
58, 59 0-6 0.6-2.0 0.16-0.18 7.4-9.0 <2 Low High Low 0.32 7 4L
Shingle 6-18 0.6-2.0 0.16-0.21 7.9-9.0 <2. Moderate High Low 0.49
18 ___ ___
60•:
Shingle 0-6 0.6-2.0 0.16-0.18 7.4-9.0 <2 Low High Low 0.32 2 4L
6-18 0.6-2.0 0.16-0.21 7.9-9.0 <2 Moderate High Low 0.49
18 ___ ___ ___
See footnote at end of table.
Exhibit K - Climate Information
6.4.11
Provide a description of the significant climatological factors for the locality.
The following climatic data is derived from Tables extracted from the 1980 Weld County Soil
Survey - Southern Part.
EXHIBIT K- Climate Information 1
Colorado Division of Mineral s& Geology Regular Impact [112] Construction Material Permit
Sand Land, Inc. - Kurtz Resource Recovery&Development Project -January 1999
92 SOIL SURVEY
TABLE 1.--TEMPERATURE AND PRECIPITATION DATA
T
Temperatures Precipitation)
r
2 years in 2 years in 10;
10 will have-- _ Average will have-- ; Average
Month Average Average Average number of Average ;number of Average
daily daily daily Maximum Minimum growing Less More ;days with snowfall
maximum minimum temperature temperature degree than-- than--;0.10 inch
higher lower days? ; or more
than-- than--
F of op_— — of'- of In In In T
In
January---- 39.9 10.5 25.3 65 -19 37 .35 .08 .55 1 5.3
February--- 45.3 16.4 30.9 71 -11 57 .29 .15 .41 1 4.6
March 51.2 22.5 36.8 78 -4 100 .76 .30 1.12 I 3 8.1 .
April 61.8 32.7 47.3 84 12 248 1.36 .46 2.07 I 3 4.3
May 72.6 43.3 58.0 92 27 558 2.16 .87 3.20 5 .3
June 82.8 52.0 67.4 100 39 822 1.81 .74 2.67 4 .0
July 89.3 57.3 73.4 100 47 1,035 1.24 .47 1.85 1 3 .0
August 86.9 54.9 70.9 99 43 '958 1.22 .42 1.85 I 3 .0
September 77.8 44.6 61.3 94 29 639 1.33 .36 2.10 3 .6
October 66.8 33.8 50.3 85 16 333 .91 .22 1.46 I 2 3.0
November 50.8 21.7 36.3 74 -1 65 .53 .14 .84 2 5.4
December 42.0 13.9 28.0 67 -13 8 .31 i .04 .52 1 4.1
Year 63.9 33.6 48.8 101 -21 4,860 12.27 9.55 14.84 31 35.7
I Recorded in the period 1951-74 at Greeley, CO.
2A growing degree day is an index of the amount of heat available for plant growth. It can be calculated
by adding the maximum and minimum daily temperatures, dividing the sum by 2, and subtracting the temperature
below which growth is minimal for the principal crops in the area (400 F).
WELD COUNTY, COLORADO, SOUTHERN PA. 93
TABLE 2.--FREEZE DATES IN SPRING AND FALL
Minimum temperature1
Probability 24° F 2S6F -`-- -326 F
or lower or lower or lower
Last freezing
temperature
in spring:
1 year in 10
later than-- April 28 May 11 May 24
2 years in 10
later than-- April 22 May 5 May 19
5 years in 10
later than-- April 11 April 25 May 10
First freezing
temperature
in fall:
1 year in 10
earlier than-- I October 4 September 25 September 16
2 years in 10
earlier than-- I October 10 October 1 September 21
5 years in 10
earlier than-- I October 21 October 11 September 30
1Recorded in the period 1951-74 at Greeley, CO.
TABLE 3•--GROWING SEASON LENGTH
Daily minimum temperature
during growing season1
Probability Higher Higher Higher
than than than
24° F 28° F 32° F
Days Days Days
9 years in 10 166 147 122
8 years in 10 175 155 129
5 years in 10 192 168 143
2 years in 10 209 18? 156
1 year in 10 218 189 163
1Recorded in the period 1951-74 at Greeley, CO.
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