**NATURAL RESOURCES CONSERVATION SERVICE**

**Idaho**

**CONSTRUCTION SPECIFICATIONS**

**FOR**

**WETLAND ENHANCEMENT**

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(Owner/Operator) (Project Title)

GENERAL

Installation shall be in accordance with an approved design and plan.
Details of construction shown on the drawings, but not included herein,
are considered as a part of this specification. Construction activities
shall be in accordance with applicable Occupational Safety and Health
Administration (OSHA) regulations.

SITE PREPARATION

Designated borrow areas for channel block fill materials and the
foundation areas for channel blocks shall be cleared of all trees,
brush, logs and debris. Prior to placing fills, the foundation area
shall be roughened to assure good bond between foundation and fill
materials.

Stripping materials shall be used in the random fills.

BORROW AREAS

Borrow areas shall be excavated and shaped as designated on the
drawings.

##### COMPACTED EARTHFILL AND BACKFILL

[Channel Block Fill Material]{.underline}. All fill materials shall be
obtained from excavations required for other parts of the work and
approved borrow areas. The selection, blending, routing and disposition
of materials within the channel block shall be subject to the approval
of the technician.

Fill materials shall contain no sod, brush, roots or other perishable or
unsuitable material.

Cobbles and rock fragments having a maximum dimension of more than six
inches shall be removed from the materials prior to compaction.

[Placement]{.underline}. The placing and spreading of the fill material
shall start at the lowest point of the foundation. The fill shall be
brought up in approximately horizontal layers and of such thickness that
the required compaction can be obtained with the equipment used.

[Moisture]{.underline}**.** The moisture content of fill material shall
be maintained within the range required to limit the adherence of the
fill material to the treads/tracks of equipment and ensure the crushing
and blending of the soil clods.

Generally, when soil material is squeezed in the hand it will retain a
ball shape, but there will not be free water on the surface.
Supplemental water, when required, may be applied by sprinkling the
materials on the fill. Uniform distribution of the moisture shall be
obtained by discing, blading or other approved method prior to
compaction.

##### 

##### COMPACTION METHODS

Compaction shall meet the requirements of the method designated and
described below:

1\. [Sheepsfoot roller]{.underline} -- The maximum layer thickness shall
be 8 inches before compaction. The roller shall have staggered,
uniformly spaced tamping feet and be equipped with suitable cleaners.
The weight of the roller shall be not less than 2,500 pounds per foot of
width. The maximum speed of the compaction equipment shall be 3 miles
per hour. The entire surface of each layer placed shall receive six
passes of this equipment to attain the necessary compaction. Adjustment
in the number of passes may be necessary during construction.

2*.* [Pneumatic tired equipment]{.underline} -- The maximum layer
thickness before compaction shall be 6 inches. A loaded scraper or wheel
tractor may be considered a pneumatic roller. The wheels of this
equipment must pass over 95 percent of the surface of each lift before a
new lift is placed.

3\. [Track laying equipment (Bulldozer]{.underline}) -- The maximum
layer thickness before compaction shall be 4 inches. The tracks of the
equipment must pass over 95 percent of the surface of each lift before a
new lift is placed.

Compliance with compaction requirements will be determined by
observation of performance applicable method. Fill not meeting the
specified requirements shall be reworked or removed and replaced with
acceptable fill.

##### CONDUITS

Pipe shall be of the type, size and pressure rating shown on the
drawings and shall meet the requirements of the appropriate material
specifications.

Steel pipe and fittings shall be galvanized and meet the requirements of
AWWA Specification C-200.

Plastic pipe shall comply with ASTM Specifications:

-   D 1527 or D 2282 for AcrylonitrileButadiene-Styrene (ABS).

-   D 2104, D 2239, D 2447, D 2737 or D 3035 for Polyethlene (PE).

-   D 1785, D 2241, D 2672 or D 2740 for Polyvinyl Chloride (PVC).

-   D 2513 for Thermoplastic Gas Pressure Pipe.

-   D3350 and D 2837 for PE3408 HDPE Pipe.

The pressure rating of fittings shall meet or exceed the strength
requirements of the pipe. All fittings shall be of a material that is
recommended for use with the type of pipe specified. As appropriate,
plastic pressure pipe fittings shall conform to ASTM Specifications D
2464, D 2466, D 2467, D 2468, D 2609, D 2683, D 3139 and/or D 3261.

Solvents for solvent-welded, plastic pipe joints shall conform to one of
the following ASTM specifications as appropriate: D 2235, D 2564, or D
2855. Rubber joints for pipe joints shall conform to ASTM F 477,
Elastomeric Seals (Gaskets) for Joining Plastic Pipe.

Pipelines to convey water that may be used for human consumption shall
meet the requirements of the Idaho Department of Health and Welfare for
material and installation, and plastic pipe shall be marked with NSF
approval.

[Installation]{.underline}

The pipe trench shall be excavated at the required location and depth as
shown on the drawings and/or staked in the field. The bottom of the
trench shall be reasonably smooth so that pipe will be properly
supported.

Trenches for pipelines shall be free of rocks and other sharp-edged
materials. Plastic pipe shall be placed in a \"snake\" like position.
Semi-rigid pipe may require expansion joint couplers.

Plastic pipelines may be placed by \"plow-in\" equipment where soils are
suitable, and rocks and boulders will not be detrimental to the pipe.

Pipelines shall be placed so they are protected against hazards imposed
by traffic, farm operations, freezing temperatures or soil cracking.

Pipelines shall have a minimum cover of 18 inches. Other means of
protection must be provided where the depth required for protection is
impractical due to shallow soils over rock or for other reasons, i.e.,
mounding of backfill. Pipelines designated for winter use shall be
buried the greater of (1) a minimum of three (3) feet, (2) below the
depth of the anticipated frost line or (3) minimum depth shown on the
drawings.

To minimize thermal stresses, installation should be planned to avoid
exposing pipe to high temperatures prior to backfilling.

CONCRETE

Concrete work under these specifications shall be constructed to the
dimensions, lines and grades as shown on the drawings. The subgrade for
concrete shall be prepared as shown on the drawings or as directed by
the technician.

[Concrete compressive strength]{.underline} shall be at least 4000 psi
at 28 days. The mix design shall be in accordance with ASTM C 94 and
this specification. When requested by the technician, the supplier shall
furnish design mix and cylinder break test data.

[Cement]{.underline} shall be low alkali, Type II Portland cement.

[Coarse aggregate]{.underline} shall be a maximum size of

1-1/2 inches per designations in ASTM C 33.

[Air entrainment]{.underline} conforming to the requirements of ASTM C
260 shall be used. The air content shall be 5 to 7 percent.

[Forms]{.underline} shall conform to the shapes, lines and dimensions as
shown on the drawings. They shall be braced and/or tied together so as
to maintain position and shape and be sufficiently tight to prevent
leakage of mortar. Forms shall be thoroughly oiled or wetted and cleaned
of debris prior to placement of concrete. [Forms shall not be removed
without the approval of the technician]{.underline}.

[Reinforcing steel]{.underline} shall be deformed bars and be free from
rust, oil, grease, paint or other deleterious matter. Items to be
embedded in the concrete shall be positioned accurately and firmly
anchored to prevent displacement during placement of concrete.

[Placement]{.underline}. The concrete shall be deposited as closely as
possible to its final position and shall be worked into the corners and
angles of the forms and around all reinforcement and embedded items in a
manner to prevent segregation of aggregates or excessive laitance.
Consolidation of concrete may be accomplished by means of internal-type
mechanical vibrators, rodding, spading or hand tamping.

[Construction joints]{.underline} shall be provided as shown in the
plans or as approved by the engineer. Joints shall be thoroughly cleaned
and laitance removed before a new pour is made. Each joint shall be
wetted immediately before the placing of new concrete.

[Finishing]{.underline}. After the concrete has been consolidated, the
unformed surfaces shall be given a wood float finish. Immediately after
form removal, formed surfaces shall be cleaned of all defective concrete
and effectively repaired. Snap ties shall be removed and the holes
mortared.

[Protection and Curing]{.underline}. Concrete shall be prevented from
drying for a curing period of at least 7 days after it is placed.
Exposed surfaces shall be kept continuously moist for the entire period.
For formed surfaces, the protection may be accomplished by leaving the
forms in place and keeping them wet for the entire curing period.
Moisture shall be maintained by sprinkling, flooding or fog spraying or
by covering with continuously moistened canvas, cloth mats, straw, earth
or other approved material. In lieu of water curing, the concrete shall
be cured by spraying with an approved sealing compound. The sealing
compound shall be applied as soon as practicable after the concrete is
finished. All surfaces shall be kept moist until the compound is
applied.

[Concreting in Cold Weather]{.underline}. Before any concrete is placed,
all ice, snow and frost shall be completely removed from all surfaces to
be in contact with the new concrete, and the temperature of these
surfaces shall be raised to as close as may be practical to the
temperature of the new concrete that is to be placed thereon. No
concrete shall be placed on a frozen subgrade or on one that contains
frozen materials. Concrete shall not be mixed or placed when daily
minimum atmospheric temperature is less than 40 degrees F. unless
facilities are provided to ensure the adequate protection of the
concrete. Temperature of the concrete at the time of placing shall not
be less than 50 degrees F. nor more than 90 degrees F. The temperature
of all aggregates and mixing water shall be not more than 100 degrees F.
when introduced into the mixer. [The use of accelerators or antifreeze
compounds will not be allowed.]{.underline}

FENCING

[Posts]{.underline} may be galvanized steel or wood. Steel posts should
be a minimum of 6.5 feet long and wood posts a minimum of 7.5 feet long.
All wood materials except Orange Osage, Western Red Cedar, Juniper and
Black Locust that have contact with the soil shall be treated with an
EPA-registered wood preservative. Wood posts shall be treated from the
butt end of the post to a distance of at least 30 inches for line posts
and 36 inches for all corner, gate and brace posts. Minimum top diameter
for wood posts is 4 inches. All posts shall be firmly set into the
ground, braced at all corners and turns and spaced as shown on the
drawings, but not to exceed 20 feet apart.

[Wire]{.underline}. Barbed wire shall be a minimum of two strands of
12-14 gage, galvanized wire. Woven wire shall be galvanized, aluminum or
plastic coated. Top and bottom wires shall be a minimum of 11 gage and
intermediate line and stay wires shall be a minimum of 14-1/2 gage.

[Hardware]{.underline}. Wire ties, clamps, staples and related fence
hardware shall have equivalent coating to the fencing being installed.

[Pole or timber fence]{.underline} equivalent to standard barbed wire
fence in usefulness and durability may be used as an alternate when
authorized by the responsible technician.

ADDITIONAL SPECIFICATIONS

NRCS Construction Specifications for Structure for Water Control (587)
may also apply.