96M03/29/06

S306-96M.doc

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  Include Subsection 725.02 and the following with projects requiring
  dust palliatives:

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**Section 306. - DUST PALLIATIVE**

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following:]{.underline}

**Description**

**306.01** This work consists of furnishing and applying one or more
applications of a dust palliative on a prepared surface.

**Material**

**306.02** Conform to the following Subsections:

> Blotter 703.13
>
> Calcium chloride 725.02
>
> Calcium chloride flake 725.02
>
> Emulsified asphalt 702.03
>
> Lignosulfonate 725.20
>
> Magnesium chloride 725.02
>
> Water 725.01

**Construction Requirements**

**306.03 General.** Use distributor equipment conforming to Subsection
409.04, except heating capability is not required. Equip the distributor
with a hose and nozzle for areas inaccessible to the distributor and for
touch-up work. Do not apply a dust palliative when the weather is foggy
or rainy or when rain is anticipated within 24 hours of application. Do
not apply chloride brines, emulsified asphalt, or lignosulfonate when
the ground is frozen.

Protect the surfaces of structures and trees from splatter or marring
during application. Use multiple applications at a reduced rate if
necessary to prevent runoff. Do not discharge dust palliative into
streams.

**306.04 Preparation and Application.** Prepare the roadbed by blading
and shaping to leave 25 to 50 millimeters of relatively loose material
on the surface.

**(a) Emulsified asphalt.** When a slow setting emulsified asphalt is
used, dilute it with water until the emulsion contains 20 to 30 percent
residual asphalt. The CO will approve the exact proportion. Thoroughly
blend the emulsified asphalt with the added water. When the ambient air
temperature is 4°C or above, apply according to Subsection 409.08.

**(b) Lignosulfonate, calcium chloride, or magnesium chloride.** Water
the loose material so it is visibly moist.

When lignosulfonate is used, dilute it with water until the mixture
contains a minimum 48 percent concentration. When calcium chloride brine
is used, provide a minimum 36 percent concentration. When magnesium
chloride brine is used, provide a minimum 28 percent concentration. When
calcium chloride flake is used, provide flakes with a minimum 77 percent
purity.

The CO will approve the exact proportion. Thoroughly mix the components.
Apply when the ambient air temperature is 4°C or above. Apply liquid
concentrations at a rate of 1.4 to 2.7 liters per square meter as
approved. Apply the chloride flakes at the rate of 0.5 to 1.1 kilograms
per square meter as approved.

Distribute the dust palliative uniformly throughout the layer, moisten
as necessary, and compact the surface.

**306.05 Maintenance and Opening to Traffic.** Do not permit traffic
treated surface until the dust palliative has penetrated and cured
enough to prevent excessive pickup under traffic. If it becomes
necessary to permit traffic before that time, apply blotter as
necessary.

**306.06 Acceptance.** Dust palliative material (emulsified asphalt,
lignosulfonate, calcium chloride, calcium chloride flake, and magnesium
chloride) will be evaluated under Subsection 106.03.

When lignosulfonate is furnished, provide a commercial certification
that includes the following information for each shipment: date,
identification number (truck, trailer, etc.), net mass, net volume at
15°C, specific gravity at 15°C, percent solids by weight, pH, base
cation, and brand name.

Application of dust palliative will be evaluated under Subsections
106.02 and 106.04.

**Measurement**

**306.07** Measure dust palliative application by the kilometer or by
the square meter.

Measure dust palliative material (emulsified asphalt, lignosulfonate,
calcium chloride, calcium chloride flake, and magnesium chloride) by the
metric ton. Mass measurements apply to the diluted quantity.

**Payment**

**306.08** The accepted quantities, measured as provided above, will be
paid at the contract price per unit of measurement for the pay items
listed below that are shown in the bid schedule. Payment will be full
compensation for the work prescribed in this section. See Subsection
109.05.

Payment will be made under:

**Pay Item Pay Unit**

30601 Dust palliative application Kilometer

30602 Dust palliative application Square meter

30603 Emulsified asphalt Metric ton

30604 Lignosulfonate Metric ton

30605 Calcium chloride Metric ton

30606 Magnesium chloride Metric ton

30707 Calcium chloride flake Metric ton