C04_Attachment 1 - Maps and Specifications.pdf

Prepared with assistance from USDA-Natural Resources Conservation ServiceUSDA is an equal opportunity provider, employer, and lender

U.S. DEPARTMENT OF AGRICULTURE NATURAL RESOURCES CONSERVATION SERVICE

Date: 1/21/2026

Location of Map Center: 96°8'39"W 46°7'45"N

Aastad Western OTTER TAIL

Hexagon

Client(s): Mike LeJuene 612-554-9991 Western 25, Otter Tail County Easement Acres: 52.2 Assisted By: Jon Frie

LeJeune WRP 6663220100G48

Wetland Restoration Map

County Boundary

Civil Townships

PLS Sections

EB_1125

Imagery

RGB

Red: Band_1

Green: Band_2

Blue: Band_3

C us to m er F ol de r:

D

:\D ou gl as

\P re se rv at io n F ar m s\

³ 0 640320

Ft

Wetland Restoration Drop Inlet Structure Replacement

Access

Prepared with assistance from USDA-Natural Resources Conservation ServiceUSDA is an equal opportunity provider, employer, and lender

U.S. DEPARTMENT OF AGRICULTURE NATURAL RESOURCES CONSERVATION SERVICE

Date: 1/21/2026

Location of Map Center: 96°5'58"W 46°12'25"N

Aastad

Aurdal

Aurdal

Buse

Carlisle

Dane Prairie

Fergus Falls Fergus Falls

Fergus Falls

Orwell

Orwell

Tumuli Western

OTTER TAIL

Hexagon

Client(s): Mike LeJuene 612-554-9991 Western 25, Otter Tail County Easement Acres: 52.2 Assisted By: Jon Frie

LeJeune WRP 6663220100G48

Wetland Restoration Map

County Boundary

Civil Townships

EB_1125

Imagery

RGB

Red: Band_1

Green: Band_2

Blue: Band_3

C us to m er F ol de r:

D

:\D ou gl as

\P re se rv at io n F ar m s\

³ 0 100005000

Ft

Project Location

Interstate 94

NATURAL RESOURCES CONSERVATION SERVICE

MINNESOTA

CONSTRUCTION AND MATERIAL SPECIFICATIONS

FOR

LeJeune

Outlet Repair

PROJECT

West Ottertail COUNTY, MN

Approved by: ______________________________ ______________ Signature Date

Landowner: ________________________________ ______________ Signature Date

Contractor: ________________________________ ______________ Signature Date

INDEX OF SPECIFICATIONS

SPECIFICATIONS

MN-5 Pollution Control MN-6 Seeding, Sprigging, and Mulching

MN-21 Excavation MN-23 Earthfill MN-26 Topsoiling MN-32 Structure Concrete MN-34 Steel Reinforcement MN-51 Corrugated Metal Pipe MN-61 Rock Riprap CS-85 Conduit Slip-Lining MN-95 Geotextile

MN-252 Steel Sheet Piling MS-511 Steel Piles MS-522 Aggregate for Portland Cement Concrete MS-523 Rock for Riprap MS-531 Portland Cement MS-532 Supplementary Cementitious Materials MS-533 Chemical Admixtures for Concrete MS-534 Concrete Curing Compound MS-539 Steel Reinforcement for Concrete MS-551 Coated Corrugated Steel Pipe MS-581 Metal MS-582 Galvanizing MS-592 Geotextile

NRCS-Minnesota (210-VI-NEH, May 2005) MN5-1

Minnesota Construction Specification 5—Pollution Control

1. Scope

The work consists of installing measures or performing work to control erosion and minimize the production of sediment and other pollutants to water and air from construction activities.

2. Material specification

All material furnished shall meet the requirements of the material specifications listed in section 7 of this specification.

3. Erosion and sediment control measures and works

The measures and works shall include, but are not limited to, the following:

Staging of earthwork activities—The excavation and moving of soil materials shall be scheduled to minimize the size of areas disturbed and unprotected from erosion for the shortest reasonable time.

Seeding—Seeding to protect disturbed areas shall occur as soon as reasonably possible following completion of that earthwork activity.

Mulching—Mulching to provide temporary protection of the soil surface from erosion.

Diversions—Diversions to divert water from work areas and to collect water from work areas for treatment and safe disposition. They are temporary and shall be removed and the area restored to its near original condition when the diversions are no longer required or when permanent measures are installed.

Stream crossings—Culverts or bridges where equipment must cross streams. They are temporary and shall be removed and the area restored to its near original condition when the crossings are no longer required or when permanent measures are installed.

Sediment basins—Sediment basins collect, settle, and eliminate sediment from eroding areas from impacting properties and streams below the construction site(s). These basins are temporary and shall be removed and the area restored to its original condition when they are no longer required or when permanent measures are installed.

Sediment filters—Straw bale filters or geotextile sediment fences trap sediment from areas of limited runoff. Sediment filters shall be properly anchored to prevent erosion under or around them. These filters are temporary and shall be removed and the area restored to its original condition when they are no longer required or when permanent measures are installed.

Waterways—Waterways for the safe disposal of runoff from fields, diversions, and other structures or measures. These works are temporary and shall be removed and the area restored to its original condition when they are no longer required or when permanent measures are installed.

Other—Additional protection measures as specified in section 7 of this specification or required by Federal, State, or local government.

4. Chemical pollution

NRCS-Minnesota (210-VI-NEH, May 2005) MN5-2

The contractor shall provide watertight tanks or barrels or construct a sump sealed with plastic sheets to dispose of chemical pollutants, such as drained lubricating or transmission fluids, grease, soaps, concrete mixer washwater, or asphalt, produced as a by-product of the construction activities. At the completion of the construction work, sumps shall be removed and the area restored to its original condition as specified in section 7 of this specification. Sump removal shall be conducted without causing pollution.

Sanitary facilities, such as chemical toilets, or septic tanks shall not be located next to live streams, wells, or springs. They shall be located at a distance sufficient to prevent contamination of any water source. At the completion of construction activities, facilities shall be disposed of without causing pollution as specified in section 7 of this specification.

5. Air pollution

The burning of brush or slash and the disposal of other materials shall adhere to state and local regulations.

Fire prevention measures shall be taken to prevent the start or spreading of wildfires that may result from project activities. Firebreaks or guards shall be constructed and maintained at locations shown on the drawings.

All public access or haul roads used by the contractor during construction of the project shall be sprinkled or otherwise treated to fully suppress dust. All dust control methods shall ensure safe construction operations at all times. If chemical dust suppressants are applied, the material shall be a commercially available product specifically designed for dust suppression and the application shall follow manufacturer's requirements and recommendations. A copy of the product data sheet and manufacturer's recommended application procedures shall be provided to the engineer 5 working days before the first application.

6. Maintenance, removal, and restoration

All pollution control measures and temporary works shall be adequately maintained in a functional condition for the duration of the construction period. All temporary measures shall be removed and the site restored to near original condition.

7. Construction details

Flow of water through the structure will be temporarily blocked with sheet piles or an earth embankment. Water will be pumped around the structure as needed. Sheet piles/ Earth embankment will be removed once the outlet is completed.

All disturbed areas will be seeded and mulched according to Minnesota Construction Specification 6 - Seeding, Sprigging, and Mulching.

NRCS-Minnesota (210-VI-NEH, May 2005) MN6-1

Minnesota Construction Specification 6—Seeding, Sprigging, and

Mulching

1. Scope

The work consists of preparing the area for treatment; furnishing and placing seed, sprigs, mulch, fertilizer, inoculants, lime, and other soil amendments; and anchoring mulch in designated areas as specified.

2. Material

Seed—All seed shall conform to the current rules and regulations of the state where it is being used and shall be from the latest crop available. It shall meet or exceed the standard for purity and germination listed in section 6.

Seed shall be labeled in accordance with the state laws and the U.S. Department of Agriculture rules and regulations under the Federal Seed Act in effect on the date of invitations for bids. Bag tag figures are evidence of purity and germination. No seed will be accepted with a test date of more than 9 months before the delivery date to the site.

Seed that has become wet, moldy, or otherwise damaged in transit or storage will not be accepted.

The percent of noxious weed seed allowable shall be as defined in the current State laws relating to agricultural seeds. Each type of seed shall be delivered in separate sealed containers and fully tagged unless exception is granted in writing by the engineer.

Fertilizer—Unless otherwise specified, the fertilizer shall be a commercial grade fertilizer. It shall meet the standard for grade and quality specified by State law. Where fertilizer is furnished from bulk storage, the contractor shall furnish a supplier's certification of analysis and weight.

When required by the contract, a representative sample of the fertilizer shall be furnished to the engineer for chemical analysis.

Inoculants—The inoculant for treating legume seeds shall be a pure culture of nitrogen-fixing bacteria prepared specifically for the species and shall not be used later than the date indicated on the container or as otherwise specified. A mixing medium, as recommended by the manufacturer, shall be used to bond the inoculant to the seed. Two times the amount of the inoculant recommended by the manufacturer shall be used except four times the amount shall be used when seed is applied using a hydraulic seeder. Seed shall be sown within 24 hours of treatment and shall not remain in the hydraulic seeder longer than 4 hours.

Lime and other soil amendments—Lime shall consist of standard ground agriculture limestone, or approved equivalent. Standard ground agriculture limestone is defined as ground limestone meeting current requirements of the State Department of Agriculture. Other soil amendments shall meet quality criteria and application requirements specified in section 6.

Mulch tackifiers—Asphalt emulsion tackifiers shall conform to the requirements of ASTM D 977, Specification for Emulsified Asphalt. The emulsified asphalt may be rapid setting, medium setting, or slow setting. Nonasphaltic tackifiers required because of environmental considerations shall be as specified in section 6.

Straw mulch material—Straw mulch shall consist of wheat, barley, oat or rye straw, hay, grass cut from native grasses, or other plants as specified in section 6. The mulch material shall be air-dry, reasonably light in color, and shall not be musty, moldy, caked, or otherwise of low quality. The

NRCS-Minnesota (210-VI-NEH, May 2005) MN6-2 use of mulch that contains noxious weeds is not permitted. The contractor shall provide a method satisfactory to the engineer for determining weight of mulch furnished.

Other mulch materials—Mulching materials, such as wood cellulose fiber mulch, mulch tackifiers, synthetic fiber mulch, netting, and mesh, are other mulching materials that may be required for specialized locations and conditions. These materials, when specified, must be accompanied by the manufacturer's recommendations for methods of application.

3. Seeding mixtures, sod, sprigs, and dates of planting

The application rate per acre for seed mixtures, sprigs, or sod and date of seeding or planting shall be as shown on the plans or as specified in section 6.

4. Seedbed preparation and treatment

Areas to be treated shall be dressed to a smooth, firm surface. On sites where equipment can operate on slopes safely, the seedbed shall be adequately loosened (4 to 6 inches deep) and smoothed. Depending on soil and moisture conditions, disking or cultipacking, or both, may be necessary to properly prepare a seedbed. Where equipment cannot operate safely, the seedbed shall be prepared by hand methods by scarifying to provide a roughened soil surface so that broadcast seed will remain in place.

If seeding is to be accomplished immediately following construction operations, seedbed preparation may not be required except on a compacted, polished, or freshly cut soil surface.

Rocks larger than 6 inches in diameter, trash, weeds, and other debris that will interfere with seeding or maintenance operations shall be removed or disposed of as specified in section 6.

Seedbed preparation shall be discontinued when soil moisture conditions are not suitable for the preparation of a satisfactory seedbed as determined by the engineer.

5. Seeding, sprigging, fertilizing, mulching, and stabilizing

All seeding or sprigging operations shall be performed in such a manner that the seed or sprigs are applied in the specified quantities uniformly in the designated areas. The method and rate of seed application shall be as specified in section 6. Unless otherwise specified, seeding or sprigging shall be accomplished within 2 days after final grading is completed and approved.

Fertilizer, lime, and other soil amendments shall be applied as specified in section 6. When specified, the fertilizer and soil amendments shall be thoroughly incorporated into the soil immediately following surface application.

The rate, amount, and kind of mulching or mesh shall be as specified in section 6. Mulches shall be applied uniformly to the designated areas. They shall be applied to areas seeded not later than

2 working days after seeding has been performed. Straw mulch material shall be stabilized within

24 hours of application using a mulch crimper or equivalent anchoring tool or by a suitable tackifier. When the mulch crimper or equivalent anchoring tool is used, it shall have straight blades and be the type manufactured expressly for and capable of firmly punching the mulch into the soil. Where the equipment can be safely operated, it shall be operated on the contour. Hand methods shall be used where equipment cannot safely operate to perform the work required.

The tackifier shall be applied uniformly over the mulch material at the specified rate, or it shall be injected into the mulch material as it is being applied. Mesh or netting stabilizing materials shall be applied smoothly, but loosely on the designated areas. The edges of these materials shall be

NRCS-Minnesota (210-VI-NEH, May 2005) MN6-3 buried or securely anchored using spikes or staples as specified in section 6.

The contractor shall maintain the mesh or netting areas until all work under the contract has been completed and accepted. Maintenance shall consist of the repair of areas damaged by water erosion, wind, fire, or other causes. Such areas shall be repaired to reestablish the intended condition and to the design lines and grades required by the contract. The areas shall be refertilized, reseeded, and remulched before the new application of the mesh or netting.

6. Construction details

Areas disturbed during construction will be seeded with the following.

SPECIES PLS RATE (LBS/ACRE)

Big Bluestem 3 Side-Oats Grama 5 Switchgrass 2 Western Wheatgrass 7 Canada Wildrye 7

Seeding Date - Spring - April 1st to June 1st Summer – July 1st to Sept. 10th *Fall - November 1 to freeze up *After November 1, a dormant seeding will be made consisting of the permanent seed mixture.

Seeding Method - Apply seed uniformly at the specified rate by broadcasting, drilling or hydro seeding.

Harrow lightly following the seeding operation to cover the seed unless the cultipacker seeder equipment cannot operate. Cover the seed by hand using a rake or similar tool.

Mulching

Straw mulch shall be applied uniformly at a rate of 3,000 lbs. minimum to 4,000 lbs. maximum per acre. Straw mulch material shall be stabilized by the use of a disk type anchoring tool or approved equivalent.

NRCS-Minnesota (210-VI-NEH, May 2005) MN21-1

Minnesota Construction Specification 21—Excavation

1. Scope The work shall consist of the excavation required by the drawings and specifications and disposal of the excavated materials.

2. Classification Excavation will be classified as common excavation or rock excavation in accordance with the following definitions or will be designated as unclassified.

Common excavation shall be defined as the excavation of all materials that can be excavated, transported, and unloaded by the use of heavy ripping equipment and wheel tractor-scrapers with pusher tractors or that can be excavated and dumped into place or loaded onto hauling equipment by means of excavators having a rated capacity of one cubic yard and equipped with attachments (such as shovel, bucket, backhoe, dragline or clam shell) appropriate to the character of the materials and the site conditions.

Rock excavation shall be defined as the excavation of all hard, compacted or cemented materials the accomplishment of which requires blasting or the use of excavators larger than defined for common excavation. The excavation and removal of isolated boulders or rock fragments larger than one cubic yard in volume encountered in materials otherwise conforming to the definition of common excavation shall be classified as rock excavation.

Excavation will be classified according to the above definitions by the Engineer, based on his judgment of the character of the materials and the site conditions.

The presence of isolated boulders or rock fragments larger than one cubic yard in size will not in itself be sufficient cause to change the classification of the surrounding material.

For the purpose of this classification, the following definitions shall apply:

Heavy ripping equipment shall be defined as a rear-mounted, heavy duty, single-tooth, ripping attachment mounted on a tractor having a power rating of 200-300 net horsepower (at the flywheel).

Wheel tractor-scraper shall be defined as a self-loading (not elevating) and unloading scraper having a struck bowl capacity of l2-20 yards.

Pusher tractor shall be defined as a track type tractor having a power rating of 200-300 net horsepower (at the flywheel) equipped with appropriate attachments.

Unclassified Excavation. Items designated as "Unclassified Excavation" shall include all materials encountered regardless of their nature or the manner in which they are removed. When excavation is unclassified, none of the definitions or classifications stated in Section 2 of this specification shall apply.

3. Blasting The transportation, handling, storage, and use of dynamite and other explosives shall be directed and supervised by a person of proven experience and ability in blasting operations.

Blasting shall be done in such a way as to prevent damage to the work or unnecessary fracturing of the foundation and shall conform to any special requirements in Section 10 of this specification.

NRCS-Minnesota (210-VI-NEH, May 2005) MN21-2

4. Use of excavated materials To the extent they are needed, all suitable materials from the specified excavations shall be used in the construction of required permanent earthfill or rockfill. The suitability of materials for specific purposes will be determined by the Engineer. The Contractor shall not waste or otherwise dispose of suitable excavated materials.

5. Disposal of waste materials All surplus or unsuitable excavated materials will be designated as waste and shall be disposed of at the locations shown on the drawings or shall be disposed of by the Contractor at sites of his own choosing away from the site of the work.

6. Bracing and shoring Excavated surfaces too steep to be safe and stable if unsupported shall be supported as necessary to safeguard the work and workmen, to prevent sliding or settling of the adjacent ground, and to avoid damaging existing improvements. The width of the excavation shall be increased if necessary to provide space for sheeting, bracing, shoring, and other supporting installations. The Contractor shall furnish, place and subsequently remove such supporting installations.

7. Structure and trench excavation Structure or trench excavation shall be completed to the specified elevations and to sufficient length and width to include allowance for forms, bracing and supports, as necessary, before any concrete or earthfill is placed or any piles are driven within the limits of the excavation.

8. Borrow Excavation When the quantities of suitable materials obtained from specified excavations are insufficient to construct the specified fills, additional materials shall be obtained from the designated borrow areas.

The extent and depth of borrow pits within the limits of the designated borrow areas shall be as directed by the Engineer.

Borrow pits shall be excavated and finally dressed in a manner to eliminate steep or unstable side slopes or other hazardous or unsightly conditions.

9. Overexcavation Excavation in rock beyond the specified lines and grades shall be corrected by filling the resulting voids with portland cement concrete made of materials and mix proportions approved by the Engineer.

Concrete that will be exposed to the atmosphere when construction is completed shall contain not less than 6 sacks of cement per cubic yard of concrete. Concrete that will be permanently covered shall contain not less than 4-1/2 sacks of cement per cubic yard. The concrete shall be placed and cured as specified by the Engineer.

Excavation in earth beyond the specified lines and grades shall be corrected by filling the resulting voids with approved compacted earthfill, except that, if the earth is to become the subgrade for riprap, rockfill, sand or gravel bedding, or drainfill, the voids may be filled with material conforming to the specifications for the riprap, rockfill, bedding or drainfill.

NRCS-Minnesota (210-VI-NEH, May 2005) MN21-3

The cost of unauthorized excavation and the backfill required to replace unauthorized excavation shall be borne by the Contractor.

10. Construction details

Excavated Topsoil will be replaced on top of work area within 7 days, following MN-26 Topsoiling Specifications.

Borrow areas must be Topsoiled following MN-26 Topsoiling Specifications. Unless otherwise planned or approved, no depressions may be left on site.

All required excavation is classified as common excavation.

Suitable excavated materials may be used as fill, following MN-23 Earthfill Specifications.

It is the responsibility of the contractor to ensure excavation work will meet the current OSHA publication 2226, "EXCAVATIONS".

All excess excavated material shall be properly deposited in a non-wetland area approved by

NRCS.

NRCS-Minnesota (210-VI-NEH, May 2005) MN23-1

Minnesota Construction Specification 23—Earthfill

1. Scope The work consists of the construction of earth embankments, other earthfills, and earth backfills required by the drawings and specifications.

Earthfill is composed of natural earth materials that can be placed and compacted by construction equipment operated in a conventional manner.

Earth backfill is composed of natural earth material placed and compacted in confined spaces or adjacent to structures (including pipes) by hand tamping, manually directed power tampers or vibrating plates, or their equivalent.

2. Material specifications All fill material shall be obtained from required excavations and designated borrow areas. The selection, blending, routing, and disposition of material in the various fills shall be subject to approval by the engineer.

Fill materials shall contain no frozen soil, sod, brush, roots, or other perishable material. Rock particles larger than the maximum size specified for each type of fill shall be removed prior to compaction of the fill.

The types of material used in the various fills shall be as listed and described in the specifications and drawings.

3. Foundation preparation Foundations for earthfill shall be stripped to remove vegetation and other unsuitable material or shall be excavated as specified.

Except as otherwise specified, earth foundation surfaces shall be graded to remove surface irregularities and shall be scarified parallel to the axis of the fill or otherwise acceptably scored and loosened to a minimum depth of 2 inches. The moisture content of the loosened material shall be controlled as specified for the earthfill, and the surface material of the foundation shall be compacted and bonded with the first layer of earthfill as specified for subsequent layers of earthfill.

Earth abutment surfaces shall be free of loose, uncompacted earth in excess of 2 inches in depth normal to the slope and shall be at such a moisture content that the earthfill can be compacted against them to produce a good bond between the fill and the abutments.

Rock foundation and abutment surfaces shall be cleared of all loose material by hand or other effective means and shall be free of standing water when fill is placed upon them. Occasional rock outcrops in earth foundations for earthfill, except in dams and other structures designed to restrain the movement of water, shall not require special treatment if they do not interfere with compaction of the foundation and initial layers of the fill or the bond between the foundation and the fill.

Foundation and abutment surfaces shall be no steeper than one horizontal to one vertical unless otherwise specified. Test pits or other cavities shall be filled with compacted earthfill conforming to the specifications for the earthfill to be placed upon the foundation.

4. Placement Earthfill shall not be placed until the required excavation and foundation preparation have been completed and the foundation has been inspected and approved by the engineer. Earthfill shall not be

NRCS-Minnesota (210-VI-NEH, May 2005) MN23-2 placed upon a frozen surface nor shall snow, ice, or frozen material be incorporated in the earthfill matrix.

Earthfill shall be placed in approximately horizontal layers. The thickness of each layer before compaction shall not exceed the maximum thickness specified in section 9 or shown on the drawings.

Materials placed by dumping in piles or windrows shall be spread uniformly to not more than the specified thickness before being compacted.

Hand compacted earth backfill shall be placed in layers whose thickness before compaction does not exceed the maximum thickness specified for layers of earth backfill compacted by manually directed power tampers.

Earth backfill shall be placed in a manner that prevents damage to the structures and allows the structures to assume the loads from the earth backfill gradually and uniformly. The height of the earth backfill adjacent to a structure shall be increased at approximately the same rate on all sides of the structure.

Earthfill and earth backfill in dams, levees, and other structures designed to restrain the movement of water shall be placed to meet the following additional requirements:

(a) The distribution of materials throughout each zone shall be essentially uniform, and the earthfill shall be free from lenses, pockets, streaks, or layers of material differing substantially in texture, moisture content, or gradation from the surrounding material. Zone earthfills shall be constructed concurrently unless otherwise specified.

(b) If the surface of any layer becomes too hard and smooth for proper bond with the succeeding layer, it shall be scarified parallel to the axis of the fill to a depth of not less than 2 inches before the next layer is placed.

(c) The top surface of embankments shall be maintained approximately level during construction with two exceptions: A crown or cross-slope of about 2 percent shall be maintained to ensure effective drainage, or as otherwise specified for drainfill or sectional zones.

(d) Dam embankments shall be constructed in continuous layers from abutment to abutment except where openings to facilitate construction or to allow the passage of streamflow during construction are specifically authorized in the contract.

(e) Embankments built at different levels as described under (c) or (d) above shall be constructed so that the slope of the bonding surfaces between embankment in place and embankment to be placed is not steeper than 3 feet horizontal to 1 foot vertical. The bonding surface of the embankment in place shall be stripped of all material not meeting the requirements of this specification and shall be scarified, moistened, and recompacted when the new earthfill is placed against it. This ensures a good bond with the new earthfill and obtains the specified moisture content and density at the contact of the inplace and new earthfills.

5. Control of moisture content During placement and compaction of earthfill and earth backfill, the moisture content of the material being placed shall be maintained within the specified range.

The application of water to the earthfill material shall be accomplished at the borrow areas insofar as practicable. Water may be applied by sprinkling the material after placement on the earthfill, if necessary. Uniform moisture distribution shall be obtained by disking.

Material that is too wet when deposited on the earthfill shall either be removed or be dried to the specified moisture content prior to compaction.

If the top surface of the preceding layer of compacted earthfill or a foundation or abutment surface in

NRCS-Minnesota (210-VI-NEH, May 2005) MN23-3 the zone of contact with the earthfill becomes too dry to permit suitable bond, it shall either be removed or scarified and moistened by sprinkling to an acceptable moisture content before placement of the next layer of earthfill.

6. Compaction Earthfill—Earthfill shall be compacted according to the following requirements for the class of compaction specified:

Class A compaction—Each layer of earthfill shall be compacted as necessary to provide the density of the earthfill matrix not less than the minimum density specified in Section 9 or identified on the drawings. The earthfill matrix is defined as the portion of the earthfill material finer than the maximum particle size used in the compaction test method specified.

Class B compaction—Each layer of earthfill shall be compacted to a mass density not less than the minimum density specified.

Class C compaction—Each layer of earthfill shall be compacted by the specified number of passes of the type and weight of roller or other equipment specified or by an approved equivalent method. Each pass shall consist of at least one passage of the roller wheel or drum over the entire surface of the layer.

Earth backfill—Earth backfill adjacent to structures shall be compacted to a density equivalent to that of the surrounding inplace earth material or adjacent required earthfill or earth backfill. Compaction shall be accomplished by hand tamping or manually directed power tampers, plate vibrators, walk-behind, miniature, or self-propelled rollers. Unless otherwise specified heavy equipment including backhoe mounted power tampers or vibrating compactors and manually directed vibrating rollers shall not be operated within 2 feet of any structure. Towed or self-propelled vibrating rollers shall not be operated within 5 feet of any structure. Compaction by means of drop weights operating from a crane or hoist is not permitted.

The passage of heavy equipment will not be allowed:

• Over cast-in-place conduits within 14-days after placement of the concrete

• Over cradled or bedded precast conduits within 7 days after placement of the concrete cradle or bedding

• Over any type of conduit until the backfill has been placed above the top surface of the structure to a height equal to one-half the clear span width of the structure or pipe or 2 feet, whichever is greater, except as may be specified in section 9.

Compacting of earth backfill adjacent to structures shall not be started until the concrete has attained the strength specified in section 9 for this purpose. The strength is determined by compression testing of test cylinders cast by the engineer for this purpose and cured at the work site in the manner specified in ASTM C 31 for determining when a structure may be put into service.

NRCS-Minnesota (210-VI-NEH, May 2005) MN23-4

When the required strength of the concrete is not specified as described above, compaction of earth backfill adjacent to structures shall not be started until the following time intervals have elapsed after placement of the concrete.

Time interval Structure (days)

Vertical or near-vertical walls with earth loading on one side only 14 Walls backfilled on both sides simultaneously 7 Conduits and spillway risers, cast-in-place (with inside forms in place) 7 Conduits and spillway risers, cast-in-place (inside forms removed) 14 Conduits, pre-cast, cradled 2 Conduits, pre-cast, bedded 1 Cantilever outlet bents (backfilled both sides simultaneously) 3

7. Reworking or removal and replacement of defective earthfill Earthfill placed at densities lower than the specified minimum density or at moisture contents outside the specified acceptable range of moisture content or otherwise not conforming to the requirements of the specifications shall be reworked to meet the requirements or removed and replaced by acceptable earthfill. The replacement earthfill and the foundation, abutment, and earthfill surfaces upon which it is placed shall conform to all requirements of this specification for foundation preparation, approval, placement, moisture control, and compaction.

8. Testing During the course of the work, the engineer will perform quality assurance tests required to identify material; determine compaction characteristics; determine moisture content; and determine density of earthfill in place. Tests performed by the engineer will be used to verify that the earthfills conform to contract requirements of the specifications. Such tests are not intended to provide the Contractor with the information required by him for the proper execution of the work and their performance shall not relieve the Contractor of the necessity to perform tests for that purpose.

Densities of earthfill requiring Class A compaction will be determined in accordance with ASTM D 1556, D 2167, D 2922, or D 2937 except that the volume and moist weight of included rock particles larger than those used in the compaction test method specified for the type of fill will be determined and deducted from the volume and moist weight of the total sample before computation of density or, if using the nuclear gauge, added to the specified density to bring it to the measure of equivalent composition for comparison (See ASTM D 4718). The density so computed is used to determine the percent compaction of the earthfill matrix. Unless otherwise specified, moisture content is determined by one of the following methods: ASTM D 2216, D 3017, D 4643, D 4944, or D 4959.

9. Construction details Fill areas must be topsoiled following MN- 26 Topsoiling Specifications.

Compaction of Backfill must be sufficient to match or exceed the density of native soil.

Fill heights from sub-cut to final grade shall be overfilled by 10% to account for settlement.

Equipment may not cross tile trench until it has been filled with at least 2 feet of friable backfill.

For Class "C" Compaction

- Max lift height will be the lessor of: 9 inches or 3 inches greater than the cleaned length of roller feet.

- Compaction will be achieved with 3 passes of a roller exerting at least 200 psi or loaded hauling equipment routed across the fill area.

- Moisture Content must be low enough that soil does not stick to tires or between roller feet, and does not bounce under the load of hauling equipment.

- Moisture Content must be high enough that soil can be kneaded into a ball that will not readily separate.

- Maximum rock size in fill material is 6 inches in diameter.

NRCS-Minnesota (210-VI-NEH, May 2005) MN26-1

Minnesota Construction Specification 26—Topsoiling

1. Scope

The work consists of furnishing and spreading topsoil to specified depths at locations shown on the drawings.

2. Quality of topsoil

Topsoil shall consist of friable surface soil reasonably free of grass, roots, weeds, sticks, rocks, or other unsuitable material. Additional quality requirements, if any, are in section 6 of this specification.

3. Furnishing

Topsoil shall be salvaged from designated earth surfaces that will be disturbed by construction activities. After designated sites have been cleared and grubbed, the topsoil shall be removed from the designated areas and stockpiled at locations shown on the drawings or acceptable to the engineer. Unsuitable material encountered during removal of topsoil shall be disposed of at locations shown on the drawings or approved by the engineer, or it will be otherwise hauled and disposed of at locations removed from the construction site. The contractor is responsible for complying with all local rules and regulations and the payment of any and all fees that may result from the disposal at locations outside the construction work limits.

4. Stockpiling

Stockpiles of topsoil shall not conflict with the requirements of Construction Specification 5, Pollution Control, when made a part of this contract.

5. Spreading

Spreading shall not be performed when the ground or topsoil is frozen, excessively wet, or otherwise in a condition detrimental to uniform spreading operations. Surfaces designated to receive a topsoil application shall be lightly scarified just before the spreading operation. Where compacted earthfills are designated to be topsoiled, the topsoil shall be placed concurrently with the earthfill and shall be bonded to the compacted fill with the compacting equipment.

Following the spreading operation, the topsoil surface shall be left reasonably smooth and without ruts or surface irregularities that could contribute to concentrated waterflow downslope.

6. Construction details

Topsoil must be salvaged from all work areas and borrow areas.

Areas beneath embankments shall be stripped to a depth of 6 inches.

Topsoil shall be replaced evenly to the extent practical, with a minimum thickness of 4 inches.

Stones larger than 3 inches in diameter shall be removed from topsoil.

NRCS-Minnesota (210-VI-NEH, October 2006) MN32-1

Minnesota Construction Specification 32--Structure Concrete

1. SCOPE

The work shall consist of furnishing, forming, placing, finishing and curing portland cement concrete and the furnishing and placing of steel reinforcement as required to build the items named in this specification or shown on the drawings.

2. MATERIALS

Portland cement - ASTM C 150, Type I or Type II.

Fly Ash - ASTM C 618, Class C or F except the loss of ignition shall not exceed 3.0 percent.

Air entraining admixtures - ASTM C 260.

Aggregates - ASTM C 33, 1-1/2" max. coarse aggregate.

Water - free of injurious amounts of deleterious substances.

Water-reducing and/or retarding admixture shall conform to ASTM C 494, Type A, B, D, F or G.

Chemical Admixtures - ASTM C 494, non-corrosive.

Plasticizing Admixtures - ASTM C 1017.

Curing compound - ASTM C 309 Type 2 Class A or B (white pigmented) or Type 1-D (clear with fugitive dye).

Reinforcing Steel - ASTM A 615, Grade 40 or Grade 60 billet-steel bars, free of foreign substances.

3. DESIGN OF THE CONCRETE MIX

The compressive strength (fc') of the concrete at 28 days shall be 4000 psi.

Fly ash may be used as a partial substitution for portland cement in an amount not greater than 25 percent (by weight) of cement in the concrete mix.

High Range Water Reducing Agents (ASTM C 494, Type F or G) or Plasticizers (ASTM C 1017) may be used to increase workability and reduce water content in accordance with manufacturer's recommendations.

4. CONSISTENCY, AIR CONTENT AND TEMPERATURE

The slump shall be 2 to 5 inches. When using High Range Water Reducing Agents (ASTM C 494, Type F or G) or Plasticizers (ASTM C 1017), the slump shall not exceed 7.5 inches.

At the time of placement, the air content by volume shall be 5 to 8 percent of the volume of the concrete.

The Contractor shall maintain the temperature of the concrete between 55°F and 90°F.

5. BATCH TICKETS

The Ready Mix Supplier shall furnish the Contractor a batch ticket before unloading the concrete at the site. The following information shall be included on the ticket: name of concrete supplier, job name, date, NRCS-Minnesota (210-VI-NEH, October 2006) MN32-2 truck number, amount of concrete in cubic yards, time loaded, and the compressive strength (fc') of the concrete at 28 days.

The Contractor shall add the following information to the batch ticket: time concrete arrived on site, mixing water added at the site, and time concrete was completely unloaded.

Copies of all batch tickets shall be provided to the Inspector.

6. HANDLING AND MIXING

Ready-mix batching, measurements and mixing shall conform to ASTM C-94.

No mixing water in excess of the amount called for by the job mix or in an amount that would cause the maximum slump to be exceeded shall be added to the concrete. Upon arrival at the job site, water may be added to the batch once. The drum or blades shall be turned 30 revolutions or more if necessary, at mixing speed. Water shall not be added to the batch at a later time. (Adding 1 gallon of water per cubic yard of concrete reduces the compressive strength of the concrete about 200 psi.)

7. FORMS

The forms shall be mortar tight, substantial, and unyielding so that the finished concrete will conform to the specified dimensions. Form surfaces shall be smooth and free from holes, dents, sags, or other irregularities. Forms shall be coated with a nonstaining form release agent before being set into place.

Metal ties or anchorages within the forms shall be equipped with cones, she-bolts or other devices that permit their removal to a depth of at least 1 inch without injury to the concrete. Ties designed to break off below the surface of the concrete shall not be used without cones.

All edges that will be exposed to view or scraping when the structure is completed shall be chamfered, unless finished with molding tools.

8. PREPARATION OF FORMS, SUBGRADE AND REINFORCING STEEL

Prior to placement of concrete, the forms and subgrade shall be free of chips, sawdust, debris, water, ice, snow, extraneous oil, mortar, or other harmful substances or coatings. The temperature of all surfaces to be in contact with the new concrete shall be no colder than 35°F. Any oil on the reinforcing steel or other surfaces required to be bonded to the concrete shall be removed. Earth surfaces shall be firm and damp.

Placement of concrete on mud, dried earth or un-compacted fill or frozen subgrade will not be permitted.

Items to be embedded in the concrete shall be positioned accurately and anchored firmly.

Reinforcing bars shall have a minimum splice length of 30 bar diameters and a minimum cover of 1-1/2" unless otherwise specified.

9. CONVEYING

Concrete shall be delivered to the site and discharged into the forms within l-1/2 hours after the introduction of the cement to the aggregates. In hot weather, the time between the introduction of the cement to the aggregates and discharge shall not exceed 45 minutes. The Inspector will allow an appropriate extension of time when the setting time of the concrete is increased by the addition of an approved admixture.

NRCS-Minnesota (210-VI-NEH, October 2006) MN32-3

10. PLACING

The Contractor shall give a 2 day notice to the Inspector each time he intends to place concrete. Concrete shall not be placed until the subgrade, forms and steel reinforcement have been inspected and approved.

Concrete shall be placed only in the presence of the Inspector.

The concrete shall be deposited as closely as possible to its final position in the forms. The use of vibrators to transport concrete in the forms or conveying equipment will not be permitted. It 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. Formed concrete shall be placed in horizontal layers not more than 20 inches thick. Concrete shall not be dropped more than 5 feet vertically unless suitable equipment is used to prevent segregation. When high range water reducing agents are used, the concrete shall not be allowed to drop more than 10 feet. Hoppers and chutes, pipes, or "elephant trunks" shall be used as necessary to prevent segregation and the splashing of mortar on the forms and reinforcing steel above the layer being placed.

Immediately after the concrete is placed in the forms, it shall be consolidated by spading, hand tamping or vibration as necessary to insure smooth surfaces and dense concrete. Each layer shall be consolidated to insure monolithic bond with the preceding layer. If the surface of a layer of concrete in-place sets to the degree that it will not flow and merge with the succeeding layer when spaded or vibrated, the Contractor shall discontinue placing concrete and shall make a construction joint according to the procedure specified in Section 11.

11. CONSTRUCTION JOINTS

Construction joints shall be made at the locations shown on the drawings. If construction joints are needed which are not shown on the drawings, they shall be placed in locations approved by the Inspector.

Construction joints shall be covered and wet cured for 7 days or until concrete placement resumes.

Steel tying and form construction adjacent to in-place concrete shall not be started until the concrete has cured at least 12 hours. New concrete shall not be placed until the hardened concrete has cured at least 12 hours.

Surfaces of construction joints shall be cleaned of all unsatisfactory concrete, laitance, coatings, stains, or debris by washing and scrubbing with a wire brush or wire broom. The surfaces of construction joints shall be kept moist for at least one hour prior to placement of the new concrete.

12. EXPANSION AND CONTRACTION JOINTS

Expansion and contraction joints shall be made only at locations shown on the drawings.

Exposed concrete edges at expansion and contraction joints shall be carefully tooled or chamfered, and the joints shall be free of mortar and concrete. Joint filler shall be left exposed for its full length with clean and true edges.

Preformed expansion joint filler shall be held firmly in the correct position as the concrete is placed.

When open joints are specified, they shall be constructed by the insertion and subsequent removal of a wooden strip, metal plate, or other suitable template in such a manner that the corners of the concrete are not chipped or broken. The edges of open joints shall be finished with an edging tool before the joint strips are removed.

NRCS-Minnesota (210-VI-NEH, October 2006) MN32-4

13. WATERSTOPS

Waterstops shall be held firmly in the correct position as the concrete is placed. Joints in metal waterstops shall be soldered, brazed, or welded. Joints in rubber or plastic waterstops shall be cemented, welded, or vulcanized as recommended by the manufacturer.

14. REMOVAL OF FORMS

Forms shall be removed in such a way as to prevent damage to the concrete. For normal concrete (without retardants or accelerators), forms may be removed after 12 hours or as specified in section 21.

15. FINISHING FORMED SURFACES

Immediately after the forms are removed:

a. All fins and irregular projections shall be removed from exposed surfaces.

b. The holes produced on all surfaces by the removal of form ties, cone-bolts, and she-bolts shall be cleaned, wetted, and filled with a dry-pack mortar. The mortar will consist of one part portland cement, three parts sand that will pass a No. 16 sieve, and just sufficient water to produce a consistency such that the filling is at the point of becoming rubbery when the material is solidly packed.

16. FINISHING UNFORMED SURFACES

All exposed surfaces of concrete shall be screeded to grade after placement and consolidation are completed. Following screeding, the surfaces shall be immediately smoothed by darbying or bull floating before any free water has bled to the surface. Any finishing operation performed on the surface of a concrete slab while bleed water is present may cause serious dusting or scaling.

The concrete shall be allowed to rest until the bleed water and water sheen has left the surface and the concrete has stiffened to where it will sustain foot pressure with only about 1/4 inch indentation. At this time edging, jointing, final floating with a magnesium float, troweling, and brooming shall be done as specified. Joints and edges that will be exposed to view or scraping shall be chamfered or finished with molding tools.

The addition of dry cement or water to the surface of the screeded concrete to expedite finishing will not be allowed.

17. CURING

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 or covered with plastic for the entire period, or until curing compound is applied.

Curing compound shall be sprayed on the moist concrete surfaces as soon as free water has disappeared and finishing is completed. The compound shall be applied at a uniform rate of not less than one gallon per 175 square feet of surface. Curing compound shall be thoroughly mixed before applying. Curing compound shall not be applied to surfaces requiring bond to subsequently placed concrete, such as construction joints, shear plates, reinforcing steel and other embedded items. If the membrane is subjected to heavy rainfall or running water within 3 hours after the compound has been applied or otherwise damaged during the curing period, the damaged area shall be resprayed at the rate of application specified above.

18. REMOVAL AND REPLACEMENT OR REPAIR

When concrete is honeycombed, damaged, or otherwise defective, the contractor shall remove and replace the structure or structural member containing the defective concrete or, where feasible, correct or repair the defective parts.