Attachment 2 Practice Specification.pdf

Natural Resources Conservation Service

Practice Specification Wetland Restoration (Code 657)

Scope The work consists of excavation and earthfill, along with furnishing and installing pipe and appurtenances for the wetland restoration as shown on the drawings and specified herein.

Utilities The landowner and/or contractor is responsible for locating all buried utilities in the project area, including drainage tile and other structural measures. The landowner will obtain all necessary permissions from regulatory agencies, or document that no permits are required.

General Carry out construction operations in a manner and sequence that erosion, air and water pollution are minimized and held within legal limits.

The completed job must present a workmanlike appearance and conform to the line, grades, and elevations shown on the drawings or as staked in the field.

Carry out all operations in a safe and skillful manner. Observe safety and health regulations and use appropriate safety measures. Contractor must assure that all state laws concerning buried utilities have been met.

Save documentation of materials used (rock or concrete delivery tickets, geotextile tags, seed tags, photographs of pipe labeling, etc) and provide to NRCS.

Remove all trees, stumps, roots, brush, weeds, and other objectionable materials from work area as designated in the drawings.

Strip designated locations for excavation and earthfill of all vegetation and topsoil containing substantial amounts of organic matter. Stockpile topsoil for use to finish areas disturbed by the construction, embankment slopes, and other required topsoil areas (if the percentage of organic materials is not too great).

Excavation To the extent they are suitable and approved by the inspector, excavated materials are to be used as fill materials.

Place, spread, level, or shape excess spoil material as shown on the construction drawings or as staked in the field. Spoil material must not be spread on existing wetland areas. The completed job must be finished to a degree so the surface can be traveled with farm-type equipment unless otherwise specified in the construction plans.

All excavations must conform to the lines, grades, elevations, bottom width, and side slopes shown on the construction plans or as staked in the field.

The location, extent, and depth of the borrow area must conform to the construction plans or as staked in the field. Borrow must not be taken within 10 feet of the embankment unless shown on the drawings.

Excavate and dress borrow pits in a manner to eliminate steep or unstable side slopes or other hazardous conditions. Side slopes of borrow pits must be no steeper than 3:1 or as specified on the construction plans. Grade and shape surfaces of the borrow pits outside of the wetland area to prevent the ponding of water unless otherwise shown in the construction plans.

Existing Subsurface Drains Remove subsurface drains as shown on the drawings. Remove all envelope, filter material or other flow-enhancing material. Fill trench in 12 inch lifts of similar soils and compact to achieve a density equal to the adjacent natural soils.

NRCS, IL SPECIFICATION - Page 1 of 2 April 2017

Susan Montgomery WRE, Tazewell Co. IL

Block the ends of abandoned and disconnected drains with manufactured caps or plugs, plug with concrete, or otherwise seal and make inoperable such that the water holding integrity of the wetland is not impaired.

Existing drains found during construction and not identified on the construction plans must be brought to the attention of the NRCS inspector.

Earthfill Scarify the foundation area where the embankment is to be built to a minimum depth of 4 inches before the fill material is placed, so that the first layer of fill material can be bonded to the foundation.

Fill material must be free of detrimental amounts of sod, roots, frozen soil, stones more than 6 inches in diameter, and other objectionable material that might endanger the performance of the embankment. The moisture content of the fill material must be sufficient to permit satisfactory compaction. Moisture content can generally be considered satisfactory if fill material can be molded into a ball with the hands without readily separating or squeezing out free water, and will easily ribbon out between the thumb and finger.

Material that is too wet must be dried and material that is too dry must have water added and mixed until the requirements are met.

Place and spread fill starting at the lowest point of the foundation and bring fill up in horizontal layers not to exceed 9 inches in thickness prior to compaction. Compact each lift by routing hauling equipment over the fill in such a manner that the entire surface will be traversed by not less than one wheel track.

The completed work must conform to the lines, grades, and elevations shown on the construction drawings or as staked in the field.

Vegetation Add topsoil, if needed to establish vegetation. Establish a protective cover of vegetation on all exposed surfaces of the embankment, spillway, outlet channel, and borrow areas exposed above the permanent waterline and non-crop areas disturbed by construction, as specified in the construction plans. Establish vegetation as soon after construction as possible.

NRCS, IL SPECIFICATION - Page 2 of 2 April 2017

Susan Montgomery WRE, Tazewell Co. IL