### **ITEM P-152 EXCAVATION AND EMBANKMENT**

DESCRIPTION

**152-1.1**  This item covers excavation, disposal, placement, and
compaction of all materials within the limits of the work required to
construct safety areas, runways, taxiways, aprons, and intermediate as
well as other areas for drainage, building construction, parking, or
other purposes in accordance with these specifications and in conformity
to the dimensions and typical section(s) shown on the plans.

**152-1.2 CLASSIFICATION.**  All material excavated shall be classified
as defined below:

**a. Unclassified Excavation.**  Unclassified excavation shall consist
of the excavation and disposal of all material, regardless of its
nature, which is not otherwise classified and paid for under the
following items.

**b. Rock Excavation.**  Rock excavation shall include all solid rock in
ledges, in bedded deposits, in unstratified masses, and conglomerate
deposits which are so firmly cemented they cannot be removed without
blasting or using rippers.  All boulders containing a volume of more
than 1/2 cubic yard (0.4 cubic meter) will be classified as \`\`rock
excavation.\'\'

**c. Muck Excavation.**  Muck excavation shall consist of the removal
and disposal of deposits or mixtures of soils and organic matter not
suitable for foundation material.  Muck shall include materials that
will decay or produce subsidence in the embankment.  It may be made up
of decaying stumps, roots, logs, humus, or other material not
satisfactory for incorporation in the embankment.

**d. Drainage Excavation.**  Drainage excavation shall consist of all
excavation made for the primary purpose of drainage and includes
drainage ditches, such as intercepting, inlet or outlet; temporary levee
construction; or any other type as shown on the plans.

**e. Borrow Excavation.**  Borrow excavation shall consist of approved
material required for the construction of embankment or for other
portions of the work in excess of the quantity of usable material
available from required excavations.  Borrow material shall be obtained
from areas within the limits of the airport property but outside the
normal limits of necessary grading, or from areas outside the airport.

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> **All material excavated shall be considered \`\`unclassified\'\'
> unless the Engineer specifies other classifications in the project
> specifications.**
>
> **Delete the classifications not applicable to a project.**

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**152-1.3 Unsuitable Excavation.**  Any material containing vegetable or
organic matter, such as muck, peat, organic silt, or sod shall be
considered unsuitable for use in embankment construction.  Material,
when approved by the Engineer as suitable to support vegetation, may be
used on the embankment slope.

CONSTRUCTION METHODS

**152-2.1 General.**  Before beginning excavation, grading, and
embankment operations in any area, the area shall be completely cleared
and grubbed in accordance with Item P‑151.

The suitability of material to be placed in embankments shall be subject
to approval by the Engineer.  All unsuitable material shall be disposed
of in waste areas shown on the plans.  All waste areas shall be graded
to allow positive drainage of the area and of adjacent areas.  The
surface elevation of waste areas shall not extend above the surface
elevation of adjacent usable areas of the airport, unless specified on
the plans or approved by the Engineer.

When the Contractor\'s excavating operations encounter artifacts of
historical or archaeological significance, the operations shall be
temporarily discontinued.  At the direction of the Engineer, the
Contractor shall excavate the site in such a manner as to preserve the
artifacts encountered and allow for their removal.  Such excavation will
be paid for as extra work.

Those areas outside of the pavement areas in which the top layer of soil
material has become compacted, by hauling or other activities of the
Contractor shall be scarified and disked to a depth of 4 inches (100
mm), in order to loosen and pulverize the soil.

If it is necessary to interrupt existing surface drainage, sewers or
under‑drainage, conduits, utilities, or similar underground structures,
the Contractor shall be responsible for and shall take all necessary
precautions to preserve them or provide temporary services.  When such
facilities are encountered, the Contractor shall notify the Engineer,
who shall arrange for their removal if necessary.  The Contractor shall,
at his/her own expense, satisfactorily repair or pay the cost of all
damage to such facilities or structures that may result from any of the
Contractor\'s operations during the period of the contract.

**152-2.2 EXCAVATION.**  No excavation shall be started until the work
has been staked out by the Contractor and the Engineer has obtained
elevations and measurements of the ground surface.  All suitable
excavated material shall be used in the formation of embankment,
subgrade, or for other purposes shown on the plans.  All unsuitable
material shall be disposed of as shown on the plans.

When the volume of the excavation exceeds that required to construct the
embankments to the grades indicated, the excess shall be used to grade
the areas of ultimate development or disposed of as directed.  When the
volume of excavation is not sufficient for constructing the fill to the
grades indicated, the deficiency shall be obtained from borrow areas.

The grade shall be maintained so that the surface is well drained at all
times.  When necessary, temporary drains and drainage ditches shall be
installed to intercept or divert surface water that may affect the work.

**a. Selective Grading.**  When selective grading is indicated on the
plans, the more suitable material as designated by the Engineer shall be
used in constructing the embankment or in capping the pavement
subgrade.  If, at the time of excavation, it is not possible to place
this material in its final location, it shall be stockpiled in approved
areas so that it can be measured for payment for rehandling as specified
in paragraph 3.3.

**b. Undercutting.**  Rock, shale, hardpan, loose rock, boulders, or
other material unsatisfactory for safety areas, subgrades, roads,
shoulders, or any areas intended for turfing shall be excavated to a
minimum depth of 12 inches (300 mm), or to the depth specified by the
Engineer, below the subgrade.  Muck, peat, matted roots, or other
yielding material, unsatisfactory for subgrade foundation, shall be
removed to the depth specified.  Unsuitable materials shall be disposed
of at locations shown on the plans.  This excavated material shall be
paid for at the contract unit price per cubic yard (per cubic meter) for
**\[ \]**.  The excavated area shall be refilled with suitable material
obtained from the grading operations or borrow areas and compacted to
specified densities.  The necessary refilling will constitute a part of
the embankment.  Where rock cuts are made and refilled with selected
material, any pockets created in the rock surface shall be drained in
accordance with the details shown on the plans.

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> **The Engineer shall specify the appropriate class of excavation. If
> rock or muck excavation is not included under paragraph 1.2,
> unclassified excavation should be specified.**
>
> **The plans shall show details for draining pockets created in rock
> cuts.**

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**c. Overbreak.**  Overbreak, including slides, is that portion of any
material displaced or loosened beyond the finished work as planned or
authorized by the Engineer.  The Engineer shall determine if the
displacement of such material was unavoidable and his/her decision shall
be final.  All overbreak shall be graded or removed by the Contractor
and disposed of as directed; however, payment will not be made for the
removal and disposal of overbreak that the Engineer determines as
avoidable.  Unavoidable overbreak will be classified as \`\`Unclassified
Excavation.\'\'

**d. Removal of Utilities.**  The removal of existing structures and
utilities required to permit the orderly progress of work will be
accomplished by someone other than the Contractor, e.g., the utility
unless otherwise shown on the plans.  All existing foundations shall be
excavated for at least 2 feet (60 cm) below the top of subgrade or as
indicated on the plans, and the material disposed of as directed.  All
foundations thus excavated shall be backfilled with suitable material
and compacted as specified herein.

**e. Compaction Requirements.**  The subgrade under areas to be paved
shall be compacted to a depth of **\[ \]** and to a density of not less
than **\[ \]** percent of the maximum density as determined by ASTM **\[
\].** The material to be compacted shall be within +/- 2 percent of
optimum moisture content before rolled to obtain the prescribed
compaction (except for expansive soils).

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> **Subgrades Under Flexible Pavements. The Engineer shall specify
> compaction to a depth of 6 inches (150 mm) and to a density of not
> less than 95 percent for cohesive soils or 100 percent for noncohesive
> soils for areas serving single gear aircraft.  For areas serving dual
> gear or dual tandem gear aircraft the Engineer shall specify the
> required compaction depths and densities as determined from AC
> 150/5320‑6C, Chapter 3, Section 2.**
>
> **Subgrades Under Rigid Pavements.  The Engineer shall specify the
> compaction depth and densities as determined from AC 150/5320‑6C,
> Chapter 3, Section 3.**
>
> **The Engineer shall specify ASTM D 698 for areas designated for
> aircraft with gross weights of 60,000 pounds (27 200 Kg) or less, and
> ASTM D 1557 for areas designated for aircraft with gross weights
> greater than 60,000 pounds (27 200 Kg).**
>
> **If nuclear density machines are to be used for density
> determination, the machines shall be calibrated in accordance with
> ASTM D 2922. The nuclear equipment shall be calibrated using blocks of
> materials with densities that extend through a range representative of
> the density of the proposed embankment material. (See attached Section
> 120 of the General Provisions for additional guidance with nuclear
> density testing)**
>
> **Include testing frequencies per square yard for density & moisture
> acceptance tests.**
>
> **AASHTO T99 or T-180 (Moisture-Density) should be specified for soils
> that are expected to have more than 30% retained on the 3/4-inch
> sieve. The moisture-density relationship test procedures ASTM D 698
> and D1557 are not applicable for materials with greater than 30
> retained on the 3/4-inch sieve. A replacement procedure (ASTM D 4718)
> for the coarse material (greater than 3/4-inch) is used with ASTM
> methods but only until up to 30 percent is retained. Maximum density
> testing (ASTM D 4253) may be used but it also limits the material
> retained on the 1-1/2-inch sieve to 30 percent. The AASHTO T-99 and
> T-180 are similar to ASTM D 698 and D 1557, except they do not limit
> the replacement of the coarse material.**

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The in‑place field density shall be determined in accordance with ASTM D
1556 or ASTM D 2167.  Stones or rock fragments larger than 4 inches (100
mm) in their greatest dimension will not be permitted in the top 6
inches (150 mm) of the subgrade.  The finished grading operations,
conforming to the typical cross section, shall be completed and
maintained at least 1,000 feet (300 m) ahead of the paving operations or
as directed by the Engineer.

In cuts, all loose or protruding rocks on the back slopes shall be
barred loose or otherwise removed to line of finished grade of slope. 
All cut‑and‑fill slopes shall be uniformly dressed to the slope, cross
section, and alignment shown on the plans or as directed by the
Engineer.

Blasting will be permitted only when proper precautions are taken for
the safety of all persons, the work, and the property.  All damage done
to the work or property shall be repaired at the Contractor\'s expense. 
All operations of the Contractor in connection with the transportation,
storage, and use of explosives shall conform to all state and local
regulations and explosive manufacturers\' instructions, with applicable
approved permits reviewed by the Engineer.  Any approval given, however,
will not relieve the Contractor of his/her responsibility in blasting
operations.

Where blasting is approved, the Contractor shall employ a vibration
consultant, approved by the Engineer, to advise on explosive charge
weights per delay and to analyze records from seismograph recordings.
The seismograph shall be capable of producing a permanent record of the
three components of the motion in terms of particle velocity, and in
addition shall be capable of internal dynamic calibration.

In each distinct blasting area, where pertinent factors affecting blast
vibrations and their effects in the area remain the same, the Contractor
shall submit a blasting plan of the initial blasts to the Engineer for
approval.  This plan must consist of hole size, depth, spacing, burden,
type of explosives, type of delay sequence, maximum amount of explosive
on any one delay period, depth of rock, and depth of overburden if any. 
The maximum explosive charge weights per delay included in the plan
shall not be increased without the approval of the engineering.

The Contractor shall keep a record of each blast fired---its date, time
and location; the amount of explosives used, maximum explosive charge
weight per delay period, and, where necessary, seismograph records
identified by instrument number and location.

These records shall be made available to the Engineer on a monthly basis
or in tabulated form at other times as required.

**152-2.3 BORROW EXCAVATION.** Borrow area(s) within the airport
property are indicated on the plans.  Borrow excavation shall be made
only at these designated locations and within the horizontal and
vertical limits as staked or as directed.

When borrow sources are outside the boundaries of the airport property,
it shall be the Contractor\'s responsibility to locate and obtain the
supply, subject to the approval of the Engineer.  The Contractor shall
notify the Engineer, at least 15 days prior to beginning the excavation,
so necessary measurements and tests can be made.  All unsuitable
material shall be disposed of by the Contractor.  All borrow pits shall
be opened up to expose the vertical face of various strata of acceptable
material to enable obtaining a uniform product.  Borrow pits shall be
excavated to regular lines to permit accurate measurements, and they
shall be drained and left in a neat, presentable condition with all
slopes dressed uniformly.

**152-2.4 DRAINAGE EXCAVATION.**  Drainage excavation shall consist of
excavating for drainage ditches such as intercepting; inlet or outlet,
for temporary levee construction; or for any other type as designed or
as shown on the plans.  The work shall be performed in the proper
sequence with the other construction.  All satisfactory material shall
be placed in fills; unsuitable material shall be placed in waste areas
or as directed.  Intercepting ditches shall be constructed prior to
starting adjacent excavation operations.  All necessary work shall be
performed to secure a finish true to line, elevation, and cross section.

The Contractor shall maintain ditches constructed on the project to the
required cross section and shall keep them free of debris or
obstructions until the project is accepted.

**152-2.5 PREPARATION OF EMBANKMENT AREA.**  Where an embankment is to
be constructed to a height of 4 feet (120 cm) or less, all sod and
vegetable matter shall be removed from the surface upon which the
embankment is to be placed, and the cleared surface shall be completely
broken up by plowing or scarifying to a minimum depth of 6 inches (150
mm).  This area shall then be compacted as indicated in paragraph 2.6. 
When the height of fill is greater than 4 feet (120 cm), sod not
required to be removed shall be thoroughly disked and recompacted to the
density of the surrounding ground before construction of embankment.

Where embankments are to be placed on natural slopes steeper than 3 to
1, horizontal benches shall be constructed as shown on the plans.

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> **The Engineer shall include benching details on the plans based on
> the type of material, degree of consolidation of the material, and the
> degree of homogeneity of the material.  The minimum width of the bench
> shall be sufficient to accommodate construction equipment.**

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No direct payment shall be made for the work performed under this
section.  The necessary clearing and grubbing and the quantity of
excavation removed will be paid for under the respective items of work.

**152-2.6 FORMATION OF EMBANKMENTS.**  Embankments shall be formed in
successive horizontal layers of not more than 8 inches (200 mm) in loose
depth for the full width of the cross section, unless otherwise approved
by the Engineer.

The grading operations shall be conducted, and the various soil strata
shall be placed, to produce a soil structure as shown on the typical
cross section or as directed.  Materials such as brush, hedge, roots,
stumps, grass and other organic matter, shall not be incorporated or
buried in the embankment.

Operations on earthwork shall be suspended at any time when satisfactory
results cannot be obtained because of rain, freezing, or other
unsatisfactory conditions of the field.  The Contractor shall drag,
blade, or slope the embankment to provide proper surface drainage.

The material in the layer shall be within +/-2 percent of optimum
moisture content before rolling to obtain the prescribed compaction.  In
order to achieve a uniform moisture content throughout the layer,
wetting or drying of the material and manipulation shall be required
when necessary.  Should the material be too wet to permit proper
compaction or rolling, all work on all of the affected portions of the
embankment shall be delayed until the material has dried to the required
moisture content.  Sprinkling of dry material to obtain the proper
moisture content shall be done with approved equipment that will
sufficiently distribute the water.  Sufficient equipment to furnish the
required water shall be available at all times.  Samples of all
embankment materials for testing, both before and after placement and
compaction, will be taken for each **\[ \]**.  Based on these tests, the
Contractor shall make the necessary corrections and adjustments in
methods, materials or moisture content in order to achieve the correct
embankment density.

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> **It is recommended that density tests be made for each 1000 cubic
> yards (760 cubic meters) of material placed per layer.  The Engineer
> may specify other frequencies as appropriate to the job size.  If it
> is necessary (because of the presence of expansive soils or other
> unusually sensitive soils) to apply special controls to the moisture
> content of the soil during or after compaction to ensure strength, the
> Engineer shall specify the appropriate moisture content.  The moisture
> limitations shall be specified using acceptable moisture ranges as
> determined by ASTM D 698 or ASTM D 1557.**
>
> **If nuclear density machines are to be used for density
> determination, the machines shall be calibrated in accordance with
> ASTM D 2922. The nuclear equipment shall be calibrated using blocks of
> materials with densities that extend through a range representative of
> the density of the proposed embankment material. (See attached Section
> 120 of the General Provisions for additional guidance with nuclear
> density testing)**
>
> **Include testing frequencies per square yard for density & moisture
> acceptance tests.**
>
> **AASHTO T99 or T-180 (Moisture-Density) should be specified for soils
> that are expected to have more than 30% retained on the 3/4-inch
> sieve. The moisture-density relationship test procedures ASTM D 698
> and D1557 are not applicable for materials with greater than 30
> retained on the 3/4-inch sieve. A replacement procedure (ASTM D 4718)
> for the coarse material (greater than 3/4-inch) is used with ASTM
> methods but only until up to 30 percent is retained. Maximum density
> testing (ASTM D 4253) may be used but it also limits the material
> retained on the 1-1/2-inch sieve to 30 percent. The AASHTO T-99 and
> T-180 are similar to ASTM D 698 and D 1557, except they do not limit
> the replacement of the coarse material.**

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Rolling operations shall be continued until the embankment is compacted
to not less than 95 percent of maximum density for noncohesive soils,
and 90 percent of maximum density for cohesive soils as determined by
ASTM **\[ \]**.  Under all areas to be paved, the embankments shall be
compacted to a depth of **\[ \]** and to a density of not less than **\[
\]** percent of the maximum density as determined by ASTM **\[ \]**.

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> **Subgrade Under Flexible Pavements.  The Engineer shall specify the
> required compaction depths and densities as determined from AC
> 150/5320‑6C, Chapter 3, Section 2.**
>
> **Subgrade Under Rigid Pavements.  The Engineer shall specify the
> required compaction depths and densities as determined from AC
> 150/5320‑6, Chapter 3, Section 3.**
>
> **The Engineer shall specify ASTM D 698 for areas designated for
> aircraft with gross weights of 60,000 pounds (27 200 kg) or less and
> ASTM D 1557 for areas designated for aircraft with gross weights
> greater than 60,000 pounds (27 200 kg).**
>
> **For soils with expansive characteristics, the maximum density should
> be determined in accordance with ASTM D 698 regardless of aircraft
> weight.**

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On all areas outside of the pavement areas, no compaction will be
required on the top 4 inches (100 mm).

The in‑place field density shall be determined in accordance with ASTM D
1556 or ASTM D 2167.

Compaction areas shall be kept separate, and no layer shall be covered
by another until the proper density is obtained.

During construction of the embankment, the Contractor shall route
his/her equipment at all times, both when loaded and when empty, over
the layers as they are placed and shall distribute the travel evenly
over the entire width of the embankment.  The equipment shall be
operated in such a manner that hardpan, cemented gravel, clay, or other
chunky soil material will be broken up into small particles and become
incorporated with the other material in the layer.

In the construction of embankments, layer placement shall begin in the
deepest portion of the fill; as placement progresses, layers shall be
constructed approximately parallel to the finished pavement grade line.

When rock and other embankment material are excavated at approximately
the same time, the rock shall be incorporated into the outer portion of
the embankment and the other material shall be incorporated under the
future paved areas.  Stones or fragmentary rock larger than 4 inches
(100 mm) in their greatest dimensions will not be allowed in the top 6
inches (150 mm) of the subgrade.  Rockfill shall be brought up in layers
as specified or as directed and every effort shall be exerted to fill
the voids with the finer material forming a dense, compact mass.  Rock
or boulders shall not be disposed of outside the excavation or
embankment areas, except at places and in the manner designated by the
Engineer.

When the excavated material consists predominantly of rock fragments of
such size that the material cannot be placed in layers of the prescribed
thickness without crushing, pulverizing or further breaking down the
pieces, such material may be placed in the embankment as directed in
layers not exceeding 2 feet (60 cm) in thickness.  Each layer shall be
leveled and smoothed with suitable leveling equipment and by
distribution of spalls and finer fragments of rock.  These type lifts
shall not be constructed above an elevation 4 feet (120 cm) below the
finished subgrade. 

Frozen material shall not be placed in the embankment nor shall
embankment be placed upon frozen material.

There will be no separate measurement of payment for compacted
embankment, and all costs incidental to placing in layers, compacting,
disking, watering, mixing, sloping, and other necessary operations for
construction of embankments will be included in the contract price for
excavation, borrow, or other items.

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> **The Engineer may specify payment for compacted \`\`Embankment in
> Place.\'\'  In this case, delete the preceding paragraph and indicate
> that payment will be made under embankment and that no payment will be
> made for excavation, borrow, or other items.**

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**152-2.7 FINISHING AND PROTECTION OF SUBGRADE.**  After the subgrade
has been substantially completed the full width shall be conditioned by
removing any soft or other unstable material that will not compact
properly.  The resulting areas and all other low areas, holes or
depressions shall be brought to grade with suitable select material. 
Scarifying, blading, rolling and other methods shall be performed to
provide a thoroughly compacted subgrade shaped to the lines and grades
shown on the plans.

Grading of the subgrade shall be performed so that it will drain
readily.  The Contractor shall take all precautions necessary to protect
the subgrade from damage.  He/she shall limit hauling over the finished
subgrade to that which is essential for construction purposes.

All ruts or rough places that develop in a completed subgrade shall be
smoothed and recompacted.

No subbase, base, or surface course shall be placed on the subgrade
until the subgrade has been approved by the Engineer.

**152-2.8 HAUL.**  All hauling will be considered a necessary and
incidental part of the work.  Its cost shall be considered by the
Contractor and included in the contract unit price for the pay of items
of work involved.  No payment will be made separately or directly for
hauling on any part of the work.

**152-2.9 TOLERANCES.**  In those areas upon which a subbase or base
course is to be placed, the top of the subgrade shall be of such
smoothness that, when tested with a 16‑foot (4.8 m) straightedge applied
parallel and at right angles to the centerline, it shall not show any
deviation in excess of 1/2‑inch (12 mm), or shall not be more than
0.05‑foot (.015 m) from true grade as established by grade hubs or
pins.  Any deviation in excess of these amounts shall be corrected by
loosening, adding, or removing materials; reshaping; and recompacting by
sprinkling and rolling.

On safety areas, intermediate and other designated areas, the surface
shall be of such smoothness that it will not vary more than 0.10 foot
(0.03 m) from true grade as established by grade hubs.  Any deviation in
excess of this amount shall be corrected by loosening, adding or
removing materials, and reshaping.

**152-2.10 TOPSOIL.**  When topsoil is specified or required as shown on
the plans or under Item T‑905, it shall be salvaged from stripping or
other grading operations.  The topsoil shall meet the requirements of
Item T‑905.  If, at the time of excavation or stripping, the topsoil
cannot be placed in its proper and final section of finished
construction, the material shall be stockpiled at approved locations. 
Stockpiles shall not be placed within **\[ \]** feet of runway pavement
or **\[ \]** feet of taxiway pavement and shall not be placed on areas
that subsequently will require any excavation or embankment.  If, in the
judgment of the Engineer, it is practical to place the salvaged topsoil
at the time of excavation or stripping, the material shall be placed in
its final position without stockpiling or further rehandling.

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> **The Engineer shall specify the appropriate clearances in accordance
> with AC 150/5370‑2C, Operational Safety on Airports During
> Construction, Appendix 1.**

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Upon completion of grading operations, stockpiled topsoil shall be
handled and placed as directed, or as required in Item T‑905.

No direct payment will be made for topsoil as such under Item P‑152. 
The quantity removed and placed directly or stockpiled shall be paid for
at the contract unit price per cubic yard (cubic meter) for
\`\`Unclassified Excavation.\'\'

When stockpiling of topsoil and later rehandling of such material is
directed by the Engineer, the material so rehandled shall be paid for at
the contract unit price per cubic yard (cubic meter) for
\`\`Topsoiling,\'\' as provided in Item T‑905.

METHOD OF MEASUREMENT

**152-3.1**  The quantity of excavation to be paid for shall be the
number of cubic yards (cubic meters) measured in its original position.

Measurement shall not include the quantity of materials excavated
without authorization beyond normal slope lines, or the quantity of
material used for purposes other than those directed.

**152-3.2**  Borrow material shall be paid for on the basis of the
number of cubic yards (cubic meters) measured in its original position
at the borrow pit.

**152-3.3**  Stockpiled material shall be paid for on the basis of the
number of cubic yards (cubic meters) measured in the stockpiled position
as soon as the material has been stockpiled.

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> **If the Engineer wishes to specify payment for the quantity of
> embankment in place in lieu of paying for excavation, delete paragraph
> 3.1 and substitute the following:  The quantity of embankment to be
> paid for shall be the number of cubic yards (cubic meters) measured in
> its final position.**

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**152-3.4**  For payment specified by the cubic yard (cubic meter),
measurement for all **\[excavation\] \[embankment\]** shall be computed
by the average end area method.  The end area is that bound by the
original ground line established by field cross sections and the final
theoretical pay line established by **\[excavation\] \[embankment\]**
cross sections shown on the plans, subject to verification by the
Engineer.  After completion of all **\[excavation\] \[embankment\]**
operations and prior to the placing of base or subbase material, the
final **\[excavation\] \[embankment\]** shall be verified by the
Engineer by means of field cross sections taken randomly at intervals
not exceeding 500 linear feet (150 meters).

Final field cross sections shall be employed if the following changes
have been made:

**a.**  Plan width of embankments or excavations are changed by more
than plus or minus 1.0 foot (0.3 meter); or

**b.**  Plan elevations of embankments or excavations are changed by
more than plus or minus 0.5 foot (0.15 meter).

BASIS OF PAYMENT

**152-4.1**  For \`\`Unclassified excavation\'\' payment shall be made
at the contract unit price per cubic yard (cubic meter).  This price
shall be full compensation for furnishing all materials, labor,
equipment, tools, and incidentals necessary to complete the item.

**152-4.2**  For \`\`Rock Excavation\'\' payment shall be made at the
contract unit price per cubic yard (cubic meter).  This price shall be
full compensation for furnishing all materials, labor, equipment, tools,
and incidentals necessary to complete the item.

**152-4.3**  For \`\`Muck Excavation\'\' payment shall be made at the
contract unit price per cubic yard (cubic meter).  This price shall be
full compensation for furnishing all materials, labor, equipment, tools,
and incidentals necessary to complete the item.

**152-4.4**  For \`\`Drainage Excavation\'\' payment shall be made at
the contract unit price per cubic yard (cubic meter).  This price shall
be full compensation for furnishing all materials, labor, equipment,
tools, and incidentals necessary to complete the item.

**152-4.5**  For \`\`Borrow Excavation\'\' payment shall be made at the
contract unit price per cubic yard (cubic meter).  This price shall be
full compensation for furnishing all materials, labor, equipment, tools,
and incidentals necessary to complete the item.

**152-4.6**  For \`\`Stockpiled Material\'\' payment shall be made at
the contract unit price per cubic yard (cubic meter).  This price shall
be full compensation for furnishing all materials, labor, equipment,
tools, and incidentals necessary to complete the item.

**152-4.7**  For \`\`Embankment in Place\'\' payment shall be made at
the contract unit price per cubic yard (cubic meter).  This price shall
be full compensation for furnishing all materials, labor, equipment,
tools, and incidentals necessary to complete the item.

Payment will be made under:

Item P‑152‑4.1 Unclassified Excavation---per cubic yard (cubic meter)

Item P‑152‑4.2 Rock Excavation---per cubic yard (cubic meter)

Item P‑152‑4.3 Muck Excavation---per cubic yard (cubic meter)

Item P‑152‑4.4 Drainage Excavation---per cubic yard (cubic meter)

Item P‑152‑4.5 Borrow Excavation---per cubic yard (cubic meter)

Item P‑152‑4.6 Stockpiled material---per cubic yard (cubic meter)

Item P‑152‑4.7 Embankment in Place---per cubic yard (cubic meter)

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> **The Engineer shall include only those classifications shown in the
> bid schedule.**

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TESTING REQUIREMENTS

ASTM D 698 Test for Moisture‑Density Relations of Soils and
Soil‑Aggregate Mixtures, Using 5.5‑pound (2.49 kg) Rammer and 12‑inch
(305 mm) Drop

ASTM D 1556 Test for Density of Soil In Place by the Sand-Cone Method

ASTM D 1557 Test for Laboratory Compaction Characteristics of Soil Using
Modified Effort

ASTM D 2167 Test for Density and Unit Weight of Soil In Place by the
Rubber Ballon Method.

**END OF ITEM P-152**