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density with the use of standard compacting equipment. Prewatering shall be supplemented where necessary, by truck watering units, to assure that the embankment material contains the proper moisture at the time of compaction.

When payment for water on a unit basis is specified in the contract such payment will not be allowed for water that has been wasted or otherwise permitted to flow from the area being watered.

The contractor shall provide drilling equipment capable of suitably checking the moisture penetration to the full depth of the excavation.

All excess or unsuitable excavated material, including rock and boulders that cannot be used in embankments shall be disposed of as directed.

Roadway embankment of earth material shall be placed in horizontal layers not exceeding 8 inches (loose measurement) and shall be compacted as specified before the next layer is placed. Effective spreading equipment shall be used on each lift to obtain uniform thickness prior to compacting. As the compaction of each layer progresses, continuous leveling and manipulating will be required to assure uniform density. Water shall be added or removed, if necessary, in order to obtain the required density. Removal of water shall be accomplished through aeration by plowing, blading, discing, or other methods satisfactory to the Engineer. Hauling equipment shall be dispersed uniformly over the entire surface of the previously constructed layer to minimize rutting or uneven compaction.

Where embankment is to be constructed across low swampy ground that will not support the weight of trucks or other hauling equipment, the lower part of the fill shall be constructed by dumping successive loads in a uniformly distributed layer of a thickness not greater than necessary to support the hauling equipment while placing subsequent layers.

Material containing more than 25 percent of rock larger than 6 inches in greatest diameter shall be placed in layers of sufficient depth to contain the maximum size rock present in the material: provided, however, that in no case shall the thickness of layers before compaction exceed 24 inches.

Each layer shall be leveled and smoothed with suitable leveling equipment and by distribution of spalls and finer fragments or earth. The lifts shall not be constructed above an elevation 2 feet below the finished subgrade. The balance of the embankment shall be composed of suitable material smoothed and placed in layers not exceeding 8 inches in loose thickness and compacted as specified for embankments.

No stones that fail to pass a 3-inch square opening shall be left within 4 inches of the subgrade elevation.

Even though the thickness of layers is limited as provided above, the placing of individual rocks and boulders greater than 24 inches in diameter will be permitted provided that when placed, they do not exceed 48 inches in height and provided they are carefully distributed, with the interstices filled with finer material to form a dense and compact mass.

203.10 Construction of Embankment and Treatment of Cut Areas with Moisture and Density Control. Unless the special provisions state that watering and rolling are not required, all embankments shall be compacted in accordance with the following requirements:

Within the areas indicated on the plans and to the designated depth below subgrade or as directed by the Engineer for the full width of roadbed in all cut sections, earth shall be removed, except the last 6-inch layer. This 6-inch layer shall be thoroughly scarified and the moisture content increased or reduced, as necessary, to bring the material throughout this 6-inch layer to the moisture content suitable for maximum compaction. This 6-inch layer shall then be compacted to not less than the density specified below. The remainder of the area up to subgrade elevation shall be constructed of suitable material placed in accordance with subsection 203.09 and compacted to not less than the density specified below.

The Contractor shall compact the material placed in all embankment layers and the material scarified to the designated depth below subgrade in cut sections, until a uniform density of not less than 95 percent of the maximum determined by AASHO T 99, Method C, is attained, at a moisture content determined by the Engineer to be suitable for such density. The Engineer will, during progress of the work, make density tests of compacted material in accordance with AASHO T 147, T 191, T 205, or other approved field density tests, including the use of properly calibrated nuclear testing devices. A correction for coarse particles may be made in accordance with AASHO T 224-641. If, by such tests, the Engineer determines that the specified density and moisture conditions have not been attained, the Contractor shall perform additional work as may be necessary to attain the specified conditions.

203.11 Compaction of Embankments Constructed Without Moisture and Density Control. Except for rock fills and the first layer of fills over swampy ground, embankment materials shall be deposited in layers not exceeding 8 inches in thickness before compaction.

The acceptable types and application of compaction equipment will be stipulated in the special provisions.

Dumping and rolling areas shall be kept separate, and no lift shall be covered by another until compaction complying with the requirements of this subsection is secured.

203.12 Proof Rolling. When proof rolling is specified the work shall be performed and paid for in accordance with the methods and equipment set forth in the contract.

203.13

Method of Measurement

(a) Plan quantity basis.-The quantities of excavation shall be measured in accordance with subsection 109.01. When the Engineer determines, by review of the Contractor's request (as set out in subsection 109.01) or by his own inspection, the plan quantity to be inaccurate, remeasurement shall be made in accordance with (b) Measured Quantity Basis. When the roadway quantities are remeasured for payment, the undisturbed ground surface elevations which were used in the design of the project will be substituted for and used as original field cross sections. Additional cross sections may be interpolated at points where necessary to more accurately determine the quantities.

(b) Measured quantity basis.—When payment is specified on a unit volume basis for the roadway quantities actually excavated and accepted, measurement will be made in the original position, except as provided in (4) below.

Preliminary cross sections or comparable measurements will be taken of the undisturbed ground surface.

Final measurements for volume determination by the average end area method will be made as follows:

(1) Remeasurement.-Final cross sections or comparable measurements will be taken of the completed and accepted work. The measurements will include actual overbreakage in rock excavation from the backslope, not to exceed 10 percent of the quantity of rock excavation located within the slope lines shown on the plans or revised by the Engineer's stakeout.

(2) Slope stake measurement.-Slope stake measurements taken by the Engineer and plotted for the roadway prior to construction may be used in lieu of final measurements, provided the Engineer has determined that the work has been acceptably completed in conformity to the staked lines and slopes. No allowance will be made for rock overbreakage.

If the Engineer determines that the excavation is accept

able but has not been done in conformity to the staked lines and slopes, he will make final measurements in accordance with method (1) above. In this case, no payment will be made for unauthorized excavation or overbreakage outside the slope lines as staked.

(3) Miscellaneous

for

measurements.-Measurement payment will be made of authorized excavation as follows: The roadway excavation as shown in (1) and (2) above. Rock and unsuitable material below the required grade and unsuitable material beneath embankment areas.

Benches excavated in accordance with subsection 203.09. Ditches, except furrow ditches included in pay item 203 (14).

Topsoil and other material removed and stockpiled as directed.

Borrow material used in the work.

Overburden and other spoil material for case 1 borrow pits as defined in subsection 203.06.

Loose scattered rocks removed and placed as directed within the roadway.

The volume of conserved materials taken from stockpiles and used in the work, except topsoil included for payment under pay item 624 (2).

Slide material not attributable to carelessness of the Contractor.

No measurement for payment will be made of the following:

Overburden and other spoil material from case 2 borrow pits as defined in subsection 203.06.

Material excavated from cut slope rounding paid for under pay item 203(15).

Removal of water by aeration of fill material to obtain required density, unless otherwise specified.

Any volumes of water or other liquid material. Material used for purposes other than directed. Roadbed material scarified in place and used in the improvement by road-mixing or similar operations.

(4) Alternative methods of measurement.-Where it is impractical to measure material by the cross-section method due to the erratic location of isolated deposits, acceptable methods involving 3-dimensional measurements, including hauling vehicle measurements, may be used.

(c) Measurement on a linear basic.-When it is specified that an item of excavation is to be measured and paid for on a linear basis, the actual length will be measured in the units specified in the contract.

(d) Measurement of excavation items on a weight basis.

-An item of excavation may be specified to be measured and paid for on a weigh basis as shown in the bid schedule.

(e) Measurement of embankments.-When specified in the contract, embankments constructed will be measured and paid for in accordance with the terms set forth.

Where the contract does not specifically provide for payment for embankment, the work of embankment construction will not be paid for as such but will be considered incidental to the various classifications of excavation.

(f) Measurement of borrow.-Borrow will be measured and paid for by the cubic yard or ton.

(g) Measurement of subgrade treatment.-The work of stabilizing subgrade treatment areas will be measured by the square yard from the limits of the areas treated as provided in the special provisions.

(h) Measurement of water.-When payment for water is specified in the contract, the water used in the work will be measured by the MG. (1000 gallons) by means of calibrated tanks or distributors or by means of accurately calibrated water meters furnished by the Contractor.

When water is not specified as a pay item in the contract, the water used will not be measured or paid for but will be included in bid prices for other pay items of the work.

Basis of Payment

203.14 The accepted quantities of excavation and embankment pay items, determined as provided above, will be paid for at the contract price per unit of measurement for each of the pay items listed below that is included in the bid schedule.

Payment will be made under:

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