Wisconsin WisDOT Standard Specifications (within FDM) — Section 626

Effective with the December 2018 Letting 378 2019 Standard Spec ifications Section 626 Peat Humus

626.1Description

(1)This section describes selecti ng portions of the material obtained under the Excavation Marsh bid item

under the contract, or stored under a previous contract, and in corporating it into the surfaces of portions of the roadway.

626.2Materials

626.2.1 If Marsh Excavation is an Item in the Contract

(1)Select those portions of materia l encountered under the Excavation Marsh bid item that contain the

more fibrous material consisting of decomposed vegetable matter , moss, etc. from the muck-like substances. Take this material from marshes the plans or the co ntract indicates as having suitable material, to the extent that it is available or necessary for t he work intended. Place the selected material into piles separate and apart from the waste materials encountered. Locate and size these piles of selected material to ensure proper drainage, and ready and convenient handling when incorporating into the work. 626.2.2 If Marsh Excavation is N ot an Item in the Contract

(1)If stored under a previous contract, this material consists of the available quantities and character of

material stored and made available to the contractor under the contract.

626.3Construction

626.3.1 General

(1)Produce a layer approximately 6 inches deep of a uniform mixtu re of the native soil and the material

previously designated. Cover the selected areas with a layer of marsh excavation material approximately 3 to 4 inches dee p, dependent upon its consistenc y and moisture content, and incorporate it into the native soil by the appropriate equipmen t to accomplish the above-required results. After completing mixing operations, smooth and dress the surfaces to restore them to the required lines, grades, slopes, and cross-section. 626.3.2 Disposing of Surplus Material

(1)Dispose of any remaining stockpiled material as specified in 205.3.7 for marsh excavation and

disposal. 626.4 Measurement

(1)The department will measure Peat H umus by the square yard acceptably completed. The quantity

measured shall equal the actual num ber of square yards of area this material was placed on, and incorporated into, according to the contract, within the limits of the construction the plans show, or in the contract, or as the engineer directed. 626.5 Payment

(1)The department will pay for measured quantities at the contrac t unit price under the following bid

items: ITEM NUMBER DESCRIPTION UNIT

626.0200 Peat Humus SY

(2)Payment for Peat Humus is full compensation for selecting, sto ckpiling, reclaiming, loading, hauling,

placing, and incorporating in t he soil; for subsequent restoring of the surface, and disposing of surplus material; provided, that the department makes no deductions from the Excavation Marsh bid item for the quantities of materials salva ged or reclaimed from for the bid item of Peat Humus.

Effective with the December 2018 Letting 379 2019 Standard Spec ifications Section 627 Mulching

627.1Description

(1)This section describes furnishi ng, placing, and anchoring a mulch cover, usually in connection with

seeding the surfaces of the roadway.

627.2Materials

(1)Mulching material consists of straw or hay in an air-dry condition, wood excelsior fiber, wood chips, or

other suitable material of a similar nature that the engineer a pproves, and is substantially free of noxious weed seeds and objectionable foreign matter.

(2)If using tackifier, the departm ent will prequalify it before u se. Select tackifiers from the department's

erosion control prod uct acceptability list ( PAL). The contractor may obtai n a copy of the department's PAL and the prequalification procedur e for products not on the dep artment's PAL.

627.3Construction

627.3.1 General

(1)Unless directed otherwise, place the mulch on the specified ar ea within 2 days after completing the

seeding.

(2)The contractor shall not perform mulching during periods of ex cessively high winds that might preclude

proper mulch placement.

(3)Place the mulch loosely or open enough to allow some sunlight to penetrate and air to slowly circulate,

but thick enough to shade the gr ound, conserve soil moisture, a nd prevent or reduce erosion.

(4)Maintain the mulched areas and repair all areas damaged by win d, erosion, traffic, fire or other

causes. 627.3.2 Placing

(1)The contractor may perform the work as sp ecified in one of the following ways: Method A, Method B,

or Method C, or a combination o f the 3, unless a specific metho d is specified in the contract. 627.3.2.1 Method A, Netting

(1)Uniformly spread the mulching ma terial over the designated are as to a loose depth of 1/2 to 1 1/2

inches. Use a specific rate o f application; dependent on the character of the material, that results in a cover conforming to the requi rements specified above in 627.3.1 . Loosen or make fluffy the mulch material from compacted bales before spreading in place. Unless directed otherwise, begin mulching at the top of the slopes a nd proceed downward.

(2)Securely anchor straw or hay mulch by using engineer-approved netting anchored to the ground with

pegs or staples to prevent it fr om floating as the vegetation g rows. Instead of this anchorage, the contractor may secure mulch by heavy biodegradable twine fastened by pegs or staples to form a grid with 6 to 10 feet spacing.

(3)The contractor may use departmen t-approved erosion control mats, listed in the department's PAL,

instead of separately applying mulch and netting. 627.3.2.2 Method B, Tackifier

(1)Treat straw or hay with a tack ifier, blow from a machine, and uniformly deposit over designated areas

in one operation. Place straw o r hay uniformly over the area 1/2 to 1 inch deep, using 1/2 to 3 tons of mulch per acre. Mix and place tackifier according to the department's PAL. Within the above limits, the engineer will determine, on the job, the application rate of the mulch and the tackifier, and the engineer may vary the rates during mulching to produce the desi red results. Use an engineer- approved machine to place the mulc h that blows or ejects by con stant air stream a controlled quantity of mulch and applies a spray of tackifier to partially coat the straw or hay, sufficient to hold together and keep in place the deposited straw or hay. The contractor ma y apply the tackifier as an overspray in a separate operation after placing the straw or hay.

(2)Apply wood fiber, wood chips, or similar material with engineer-approved blowing machines, or other

engineer-approved methods, that p lace a controlled quantity of mulch uniformly over the area 1/2 to 1 1/2 inches deep. Treat areas receiving wood chip mulch, with one pound of available nitrogen per 1000 square feet before or after applying the chips.

(3)Throughout the process, feed the mulch material into the blowi ng machine to produce a constant and

uniform ejection from the disc harge spout, and operate in a pos ition to produce mulch of uniform depth and coverage.

Source: Wisconsin Standard Specifications for Highway and Structure Construction, 2019 Edition. Pages 387–387 of 601.

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625 Topsoil and Salvaged Topsoil

627 Mulching