S01 12FPC321Q0069 Attachment 1 - Specifications.pdf

Prepared by: Caroline Clarin NRCS Easement Wetland Restoration

NATURAL RESOURCES

CONSERVATION SERVICE

MINNESOTA

CONSTRUCTION AND MATERIALS

SPECIFICATIONS

FOR

DANIEL AND MICHELLE LORENTZ

5563221901RXP and 5563221901RYM

WETLAND RESTORATION

SEC 29 and Sec 32 T 44 N R 25 W

AITKIN COUNTY

8/2005

MN NRCS Construction Specifications Index

Site Preparation Date

MN-5 Pollution Control 5/05

MN-6 Seeding, Sprigging, and Mulching 5/05

Earthwork Date

MN-21 Excavation 5/05

MN-23 Earthfill 5/05

MN-26 Topsoiling 5/05

Metal Pipe Conduits Date

MN-51 Corrugated Metal Pipe 5/05

Riprap and Slope Protection Date

MN-61 Rock Riprap 5/05

MN-95 Geotextile 5/05

Water Control Gates and Valves Date

MN-71 Water Control Gates 5/05

Miscellaneous Structural Work Date

MN-252 Steel Sheet Piling 5/05

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. Measurement and Payment Method—For items of work for which lump sum prices are established in the contract, payment is made as the work proceeds and supported by invoices presented by the contractor that reflect actual costs. If the total of all progress payments is less than the lump sum contract prices for this item, the balance remaining for this item will be included in the final contract payment. Payment of the lump sum contract price will constitute full compensation for completion of the work.

8. Construction details for 1901RXP and 1901RYM

Pollution control is subsidiary to the mobilization costs. No separate payment will be made for pollution control.

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, 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.

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.

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 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.

NRCS-Minnesota (210-VI-NEH, May 2005) MN6-2

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.

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 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 re-fertilized, re-seeded, and re-mulched before the new application of the mesh or netting.

6. Measurement and payment

Method —For items of work for which lump sum prices are established in the contract, payment will be prorated and provided in equal amounts on each monthly progress payment estimate. The number of months used for prorating shall be the number estimated to complete the work as outlined in the contractor's approved construction schedule. The final month's prorate amount will be provided with the final contract payment. Payment as described will constitute full compensation for completion of the work.

NRCS-Minnesota (210-VI-NEH, May 2005) MN6-3

7. Construction details

1901RXP: Seeding 2.5 acres

190RYM: Seeding 5 acres

Seed all disturbed areas. Mulch all the areas as described in the plan

Mulch the areas with clean straw free of weed seed as described in section 5. Seeding, sprigging, mulching, and stabilizing.

The seeding mixture shall consist of the following species, varieties and rates of Pure Live Seed per acre.

Nurse Crop—Seed Oats at rate of 1 bushel per acre.

Common Name Scientific Name Sod/Bunch Lbs Per Acre Side-oats Grama Bouteloua curtipendula Sod 4 Switchgrass Panicum virgatum Sod 4 Western Wheatgrass Pascoptrum smithii Sod 4 Canada Wildrye Eltmus canadensis Bunch 4

Seeding dates Spring May 1st -- Sept 1st Summer N/A Dormant Nov. 1 – Freeze-up

No permanent seeding will take place during the period of Sept 1st through October 31th. A cover crop shall be seeded during this time, with a permanent seeding done as soon as possible at the next seeding window.

Seeding Method—Apply seed uniformly at the specified rate by broadcasting or drilling. Harrow lightly following the seeding operation to cover the seed unless the cultipacker seeder equipment cannot operate then cover the seed by hand using a rake or similar tool or a drag behind an ATV.

Mulch Certification—Mulch shall consist of clean grain oat or wheat straw that is certified by the Minnesota Crop Improvement Association (MCIA) to be noxious weed free. For information on obtaining certified mulch or getting a source of straw mulch certified go to the web address:

http://www.mncia.org/noxious-weed-seed-free-forage-mulch

Payment will be lump sum for each of the following

• Disturbed Area Seeding and Mulching

Seeding of a cover crop is subsidiary to Disturbed area seeding and will not result in additional payment.

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.

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

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.

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. Over-excavation 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. Measurement and payment Method—For items of work for which lump sum prices are established in the contract, payment is made as the work proceeds and supported by invoices presented by the contractor that reflect actual costs. If the total of all progress payments is less than the lump sum contract prices for this item, the balance remaining for this item will be included in the final contract payment. Payment of the lump sum contract price will constitute full compensation for completion of the work.

11. Construction details

1901RXP: Excavation is included in the Strip and Stockpile, Ditch Construction, Berm and Ditch Fill Construction and Rock Rip-rap Outlet, items. Excavation is subsidiary to these line items. No separate payment will be made for excavation.

1901RYM: Excavation is included in the Strip and Stockpile, Construct Ditch, and Construct Ditch Fill items. Excavation is subsidiary to these line items. No Separate payment will be made for excavation.

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

Minnesota Construction Specification 23—Earthfill

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.

NRCS-Minnesota (210-VI-NEH, May 2005) MN23-2

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 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.

NRCS-Minnesota (210-VI-NEH, May 2005) MN23-3

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 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 two passes of the construction equipment including but not limited to a bulldozer or tractor over the entire surface of the layer. The lift height of each layer will not exceed 6 inches.

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. Measurement and payment Method—For items of work for which lump sum prices are established in the contract, payment is made as the work proceeds and supported by invoices presented by the contractor that reflect actual costs. If the total of all progress payments is less than the lump sum contract prices for this item, the balance remaining for this item will be included in the final contract payment. Payment of the lump sum contract price will constitute full compensation for completion of the work.

9. Construction details

1901RXP Earthfill is included in the Berm and Ditch Fill Construction item on the bid schedule and is subsidiary to this item. No separate payment will be made for earthfill.

1901RYM Earthfill is included in the Construct Ditch Fill item on the bid schedule and is subsidiary to this item. No separate payment will be made for earthfill.

Compaction shall be accomplished by at least two passes of the construction equipment including but not limited to a bulldozer or tractor over the entire surface of the layer. The lift height of each layer will not exceed 6 inches.

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

Minnesota Construction Specification 26—Topsoiling

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. Measurement and payment Method—For items of work for which lump sum prices are established in the contract, payment is made as the work proceeds and supported by invoices presented by the contractor that reflect actual costs. If the total of all progress payments is less than the lump sum contract prices for this item, the balance remaining for this item will be included in the final contract payment. Payment of the lump sum contract price will constitute full compensation for completion of the work.

7. Construction details

1901RXP: Stripping, stockpiling, and re-spreading topsoil is included in the Strip, Stockpile, Respread Topsoil item the bid sheet and shall be paid by the lump sum method.

1901RYM: Stripping, stockpiling, and re-spreading topsoil is included in the Strip, Stockpile, Respread Topsoil item the bid sheet and shall be paid by the lump sum method.

NRCS-Minnesota (210-VI-NEH February 2015) MN51-1

Minnesota Construction Specification 51—Corrugated Metal Pipe

1. SCOPE

The work shall consist of furnishing and placing circular, arched or elliptical corrugated metal pipe and the necessary fittings.

2. MATERIAL SPECIFICATIONS

Pipe and fittings shall conform to the requirements of Material Specification 55l or Material Specification 552, whichever is specified.

Unless otherwise specified in Section 10 of this specification or as shown on the construction drawings, perforated pipe furnished shall meet the requirements for Class I perforations as described in ASTM A 760 or A 762.

3. COUPLING BANDS AND HARDWARE

Pipe joint coupling bands shall be provided meeting the requirements specified in Section 10 or as shown on the construction drawings.

Hardware consisting of coupling bands and band fastening devices such as connecting bolts, rods, lugs and angles used in conjunction with zinc-coated iron or steel pipe shall be galvanized by the hot-dip method. Hardware used in conjunction with aluminum pipe and aluminum or aluminum-zinc alloy-coated iron and steel pipe shall be of the same material as the pipe except that hot-dip galvanized or cadmium plated fasteners may be used. The surface of all band fastening devices for pipe specified with bituminous or polymer coating shall be coated with asphalt mastic materials meeting the requirements of ASTM A 849. The coupling band shall be coated similar to that specified for the pipe unless otherwise specified in Section 10 or as shown on the construction drawings.

Coupling bands shall be installed to provide straight alignment of the connecting pipe ends. Unless otherwise specified in Section 10 or as shown on the construction drawings, the band width shall be as specified in ASTM A 760 and A 762. The bands shall be positioned to overlap adjacent pipe ends equally. The coupling bands shall be corrugated to match the corrugations of the connecting pipe ends.

4. FABRICATION

Fabrication of appurtenant sections shall be done as shown on the construction drawings and described in Section 10 of this specification. The items may consist of inlet sections, outlet sections, end sections, elbows, skew or beveled sections, rod reinforced ends, cut-off collars, or headwalls.

Fabrication of these appurtenant sections shall be made from metallic-coated materials identical to those from which the attached pipe is fabricated. Fabrication shall be of a quality and finished workmanship equal to that required for the pipe.

5. HANDLING THE PIPE

The Contractor shall furnish equipment as necessary to place the pipe without damaging the pipe or coatings. The pipe shall be transported and handled in a manner to prevent damage to the pipe or coating.

NRCS-Minnesota (210-VI-NEH February 2015) MN51-2

6. LAYING AND BEDDING THE PIPE

Unless otherwise specified, the pipe shall be installed in accordance with the manufacturer's recommendations. The pipe shall be laid with the outside laps of circumferential joints pointing upstream and with longitudinal laps at the sides at about the vertical midheight of the pipe.

Field welding of corrugated galvanized iron or steel pipe will not be permitted. The pipe sections shall be joined with fabricator-supplied coupling bands meeting the specified joint requirements. The coupling shall be made as recommended by the fabricator.

The pipe shall be firmly and uniformly bedded throughout its entire length to the depth and in the manner specified on the drawings.

Perforated pipe shall be laid with the perforations down and oriented symmetrically about a vertical center line. Perforations shall be clear of any obstructions at the time the pipe is laid.

The pipe shall be loaded sufficiently during backfilling around the sides to prevent its being lifted from the bedding.

7. STRUTTING

When required, struts or horizontal ties shall be installed in the manner specified on the drawings.

Struts and ties shall remain in place until the backfill has been placed above the top of the pipe to a height of 5 feet or the pipe diameter, whichever is the greater, or has been completed if the finished height is less than 5 feet above the top of the pipe; at which time struts or ties used shall be removed by the Contractor.

8. EMBEDMENT IN CONCRETE

Special treatment shall be provided to pipe embedded in or attached to concrete when the pipe is aluminum or aluminum-coated and aluminum-zinc alloy-coated. Potential contact surfaces shall be insulated. All aluminum, aluminum-coated, and aluminum-zinc alloy-coated pipe surfaces in contact with concrete and masonry surfaces shall be coated with two coats of a bituminous paint of the cut-back type. Placement of the pipe shall be such that direct metal-to-metal contact with other metallic materials, such as embedded steel reinforcement or water control gates, is prevented.

9. REPAIR OF DAMAGED COATINGS

Any damage to the metallic coating shall be repaired by cleaning the damaged surface area by sand blasting, power disk sanding or wire brushing. All loose and cracked coating, dirt, and any products of corrosion shall be removed prior to application of two (2) coats of paint. Oil and grease materials shall be removed by use of a solvent. The surface shall be clean and dry during the painting period and until the coating has dried.

Painting shall be by use of one of the following options based upon installed exposure of the pipe as determined by the Engineer:

Normal exterior or interior atmospheric exposure:

a. Zinc dust - zinc oxide primer, Federal Specification TT-P-641, Type I or Type II, or

b. Single-package, moisture-cured urethane primer in silver metallic color, or

c. Zinc-rich cold galvanizing compound, brush, or aerosol application.

NRCS-Minnesota (210-VI-NEH February 2015) MN51-3

Submergence in water exposure:

a. Zinc dust - zinc oxide primer, ASTM D 79 and D 520

b. Zinc dust paint, ASTM D 4146

If the metallic coating is damaged in any individual area larger than 12 square inches, or if more than

0.2 percent of a total surface area of a length of pipe is damaged, the length will be rejected.

Breaks or scuffs in bituminous coatings that are less than 36 square inches in area shall be repaired by the application of two coats of hot asphaltic paint or a coating of cold-applied bituminous mastic. The repair coating shall be at least 0.05 inches thick after hardening and shall bond securely and permanently to the pipe. The material shall meet the physical requirements for bituminous coatings contained in ASTM A 849 and A 885. Whenever individual breaks exceed 36 square inches in area or when the total area of breaks exceeds 0.5 percent of the total surface area of an individual pipe section, that section of pipe will be rejected.

Bituminous coating damaged by welding of coated pipe or pipe fittings shall be repaired as specified in this Section for breaks or scuffs in bituminous coatings.

Breaks or scuffs in polymer coatings that are less than 36 square inches in area shall be repaired by the application of two coats of a polymer material similar to and compatible with the durability, adhesion and appearance of the original polymer coating. Repair of polymer precoating is described in ASTM A 762 section 11. Repair of post-coated polymer is described in ASTM A 849, section 10 and shall be a minimum thickness of 0.010 inches (10 mils) after drying. Whenever individual breaks exceed 36 square inches in area or when the total area of breaks exceeds 0.5 percent of the total surface area of an individual pipe section, that section of pipe will be rejected.

NRCS-Minnesota (210-VI-NEH February 2015) MN51-4

10. CONSTRUCTION DETAILS

The following flat gasket joining systems have been industry tested and certified by independent laboratories that they meet the leakage requirements of ASTM A 760 Section 9.2.4 [zero leakage for a minimum period of 10 minutes at a minimum pressure of 10 psi (23-ft head)].

PIPE

9C CONNECTING BAND WITH 24" WIDE FLAT GASKET

FOR 12" TO 60" DIA. HELICAL PIPE WITH REROLLED ENDS

10C CONNECTING BAND WITH 24" WIDE FLAT GASKET

FOR 12" TO 60" DIA. ANNULAR PIPE

CONNECTING BAND SECTION

24" Nominal 4 Rods and lugs

Flat gasket

1/2 Corr. (1.33") or less

26 2/3" Nominal

Flat Gasket 4 Rods and lugs

5C CONNECTING BAND WITH 12" WIDE FLAT GASKET

FOR 12" TO 48" DIA. HELICAL PIPE WITH REROLLED ENDS

12.25" Minimum 4 Rods and lugs

1/2 Corr. (1.33") or less

Flat gasket

Lugs and 2 piece rod

2 Piece band with 3" to 6" lap

Flat Gasket with 2" minimum lap

NRCS-Minnesota (210-VI-NEH February 2015) MN51-5

The corrugated steel pipe shall have 2-2/3” x ½” corrugations. The corrugations may be helical with rerolled ends and standard lock seams, or annular with close rivets and caulked seams as specified on the drawings. The close rivet details are contained in Material Specification 551.

From ASTM A760, the minimum corrugation depth is 0.44”, and the average inside diameter shall not vary more than 1% or 0.5”, whichever is greater (11.5” to 12.5” for 12” dia. pipe, and 47.5” to 48.5” for 48” dia. pipe). If the difference in pipe diameters at a joint approaches 1”, consult the manufacturer to ensure a leakage resistant joint.

The rerolled ends on helical pipe (inside and outside) shall be painted with 2 coats of paint at the plant in accordance with Section 9 of this specification.

FLAT GASKET and LUBRICANT Flat gaskets shall be 3/8” thick, closed-cell neoprene in accordance with ASTM D1056, Grade 2C2 or 2C3. Gaskets with adhesive backing shall not be permitted. The width of the gasket shall be one piece. The flat gasket shall be wrapped around the pipe joint, overlapped a minimum of 2”, and temporarily secured with tape.

The lubricant shall be pipe joint lubricant compliant with NSF Standard 61. The inside of the connecting bands shall be lubricated before placement over the flat gasket. Apply lubricant evenly and thinly over the entire surface.

CONNECTING BANDS

The flat gasket connecting band diameter shall be approximately 1” larger than the nominal pipe diameter to facilitate band installation over the flat gasket.

The bands shall be two-piece with two 3” to 6” laps.

The band width shall be as specified on the drawings.

The steel band gauge shall be as follows:

Steel Pipe Gauge (thickness) Steel Band Gauge 16 (0.064”) 16 14 (0.079”) 16 12 (0.109”) 16 10 (0.138”) 14

When placing the band under the pipe use caution to avoid getting soil between the band and pipe.

The rods shall be two-piece using ½” diameter galvanized steel. The lugs shall be standard tank lugs.

The bands shall be gently tapped with a rubber hammer (or other non-marring method) to ensure an even band seating as the rod nuts are tightened on the lugs.

1901RXP The Corrugated Metal Pipe is subsidiary to the 24” Culvert and Installation line item. No separate payment will be made for the Corrugated Metal Pipe.l

NRCS-Minnesota (210-VI-NEH, May 2005) MN61-1

Minnesota Construction Specification 61—Rock Riprap

The work shall consist of the construction of rock riprap revetments and blankets, including filter or bedding where specified.

2. Material Specifications

Rock riprap shall conform to the requirements of Material Specification MN-523, Rock for Riprap, or if so specified, shall be obtained from designated sources. It shall be free from dirt, clay, sand, rock fines, and other material not meeting the required gradation limits.

At least 30 days before rock is delivered from other than designated sources, the contractor shall designate in writing the source from which rock material will be obtained and provide information satisfactory to the engineer that the material meets contract requirements. The contractor shall provide the engineer free access to the source for the purpose of obtaining samples for testing. The size and grading of the rock shall be as specified in section 7 or on the drawings.

Rock from approved sources shall be excavated, selected, and processed to meet the specified quality and grading requirements at the time the rock is installed.

Filter or bedding aggregates when required shall conform to Material Specification 521, Aggregates for Drainfill and Filters, unless otherwise specified. Geotextiles shall conform to Material Specification 592, Geotextile.

3. Subgrade preparation The subgrade surface on which the rock riprap, filter, bedding, or geotextile is to be placed shall be cut or filled and graded to the lines and grades shown on the drawings. When fill to subgrade lines is required, it shall consist of approved material and shall conform to the requirements of the specified class of earthfill.

Rock riprap, filter, bedding, or geotextile shall not be placed until the foundation preparation is completed and the subgrade surface has been inspected and approved.

4. Equipment-placed rock riprap The rock riprap shall be placed by equipment on the surface and to the depth specified. It shall be installed to the full course thickness in one operation and in such a manner as to avoid serious displacement of the underlying material.