DEVICES
621.01 Description. (a) Temporary Seeding. This item shall
consist of the application of seed, fertilizer, and water according to these specifications to areas shown on the plans or as directed.
b.Mulch Cover. This item shall consist of the application of mulch cover as a deterrent to soil erosion. The En gineer may make a determination to place mulch cover, without seedi ng, on areas that 481 require erosion control for a short period of time; when erosion control is necessary during the midwinter season wh en seed will not germinate; or because of the nature of material use d for embankment construction. Mulch cover, including mulch anchori ng when required, shall be applied to areas shown on the pl ans, or as directed by the Engineer.
c.Erosion Control Matting. This item shall consist of the temporary placement of erosion control matting at l ocations shown on the plans or as directed by the Engineer. It wi ll generally be used in diversion ditches at the ends of berms, or at ot her locations where the flow of water is concentrated. Areas receiving matting shall be shaped and seeded, when required, before placement of the matting.
d.Baled Straw Filter Barrier. This item shall consist of baled straw staked and butted together to form a continuo us barrier for the purpose of impeding or re-directing the flow of sto rm water as necessary to prevent its discharge off site or to a Water of the State.
e.Silt Fence. This item consists of placing and securing a geotextile fabric to an existing support system or constructing a self- supporting geotextile fence where shown on the plan s or as directed by the Engineer for the purposes of impeding the fl ow of water carrying silt toward existing streams and/or across adjacent property; redirecting the flow of silt-laden water to a sedim ent basin; and/or routing clean water through the construction area.
f.Sand Bag Ditch Check. Where shown on the plans or as directed by the Engineer this item shall consist of preparing and placing sand bags in roadside ditches to impede run -off velocity of water and to prevent scouring and eroding of soil u ntil permanent erosion control items can be placed.
g.Diversion Ditch. Where shown on the plans or as directed by the Engineer this item shall consist of excavating or grading for diversion ditches to control soil erosion at select ed locations. Diversion ditches will generally be excavated above the backslopes of cuts, along the top of embankments, or across fo reslopes and backslopes to divert the run-off to vegetated areas , slope drains , downslope protection locations, or sediment basins. Sediment laden water shall not be discharged directly into natural drainage channels.
h.Sediment Basin. This item shall consist of excavating and grading a storage area to detain sediment-laden run off from 482 disturbed areas long enough to allow sediment to se ttle out. Sediment basins shall be placed at locations shown on the plans or as directed by the Engineer.
i.Drop Inlet Silt Fence. This item shall consist of placing and securing geotextile to an adequate frame around a d rop inlet to impede silt from entering the inlet. Drop inlet si lt fence shall be placed at locations shown on the plans or as direct ed by the Engineer.
j.Rock Ditch Checks. This item shall consist of constructing small dams across swales or ditches to slow concent rated storm water runoff to a non-erosive velocity. Ditch chec ks shall be constructed at locations shown on the plans or as d irected by the Engineer.
k.Sediment Removal and Disposal. This item shall consist of removing and disposing of silt collected in erosion and sediment control devices as directed by the Engineer.
l.Mulch Control Netting. This item shall consist of furnishing and installing mulch control netting to be used ove r mulch cover in areas shown on the plans or designated by the Engin eer. This is not a substitute for mulch anchoring or mulch cover. I t is to be used where additional or long term control is needed for the mulch cover.
m.Slope Drains. This work shall consist of installing a pipe and dumped riprap to convey concentrations of runof f from the top of a disturbed slope to the bottom and discharge th e runoff onto either a stabilized area, sediment basin, or dumped rip-rap as directed by the Engineer. Slope drains shall be pl aced at locations shown on the plans or as directed by the Engineer.
n.Wattles. This item shall consist of furnishing, installing , maintaining, and removing wattles at locations as d irected by the Engineer for the purpose of controlling erosion and sedimentation.
o.Triangular Silt Dikes. This item shall consist of furnishing, installing, maintaining, and the subsequent removal of a geotextile and urethane foam barrier designed to remove suspen ded soil particles from water passing through the barrier.
621.02 Materials. (a) Seed shall be of the fast germinating and
growing variety such as common rye grass, the cerea l grasses (wheat, barley, oats), or Brown Top Millet, complyi ng with the 483 requirements of the Arkansas State Plant Board and Subsection 620.02(c). Fertilizer and water shall c omply with Section 620.
b.Mulch cover and tackifier, if applicable, shall com ply with Section 620.
c.Erosion Control Matting shall comply with Section 6 26.
d.Straw for baled straw filter barrier shall consist of bales of rice, oats, barley, wheat, or rye straw, or of avai lable grasses, free of an excessive amount of noxious weeds. Bales shall be a minimum of 30" (750 mm) in length. Straw in a state of dec omposition will not be acceptable.
e.Geotextile fabric for silt fence shall comply with the requirements of Section 625 for Type 3 or Type 4 or as shown on the plans. Supports for the fabric shall be of any mat erial of sufficient strength and durability to support the fabric when loaded with silt for the entire time the barrier is needed for service.
f.Sand for sand bags shall consist of a sandy type so il or clean sand that meets the approval of the Engineer. Bags for sand shall be of a tightly woven burlap or other material that is sufficiently durable to remain intact for the time intended.
g.Geotextile for drop inlet silt fences shall be of t he type shown on the plans and comply with Section 625. Framing shall be as shown on the plans and be of sufficient strength an d durability to support the geotextile for the time needed.
h.Material for rock ditch checks shall comply with Se ction 207. Rock having a different gradation may be used when determined by the Engineer to be suitable for the purpose intende d.
i.Dumped Riprap and geotextile for sediment basin spi llway outlets shall comply with Section 816. Pipe culver t for a basin outlet shall comply with Subsection 606.02(c). Used pipe meeting these requirements may be used when determined by the Eng ineer to be suitable for the purpose intended. Rock filter sha ll comply with Subsection 207.02 for Stone Backfill.
j.Mulch Control Netting shall be a uniformly extruded , rectangular, photodegradable plastic mesh with a mi nimum weight of 0.23 ounce per square yard (8 g/sq m) and a maxi mum mesh 484 opening of 2" x 2" (50 mm x 50 mm). Staples or woo d stakes for use with mulch control netting shall be according t o Section 626.
k.Pipe for slope drains shall be 12" (300 mm) in diam eter and shall comply with Subsection 606.02 or Type C corru gated polyethylene pipe complying with AASHTO M 294. Use d pipe meeting these requirements may be used when determi ned by the Engineer to be suitable for the purpose intended. Dumped riprap shall comply with Section 816.
l.Water shall comply with Section 620.
m.Wattles shall consist of an elongated tube of netti ng filled with weed free organic material (coir, wood fibers, mulch, straw, or a combination of the previous materials) or rolls o f organic material reinforced with biodegradable netting, in accordanc e with the Table 621-1. Wattles shall be installed in accordance wi th the size shown on the detail sheet or as directed by the Engineer. Table 621-1 Wattles Wattle Type Material Coir Core 100% blended bristle and mattress grade coir f iber Netting Woven knotted coir or knotless polypropylen e net Excelsior Core Excelsior fiber with interlocking barbs and 80% bei ng 6” in length or longer Netting Polyester with 1” triangular shaped opening s Straw Core Compacted straw such as rice straw Netting Polyethylene, polypropylene, or polyester n etting Mulch Core Well decomposed organic material, 99% passing 2” Sieve Netting HDPE ⅜” knitted mesh netting Rolled Core 70% straw fiber, 30% coconut fiber Netting Leno woven jute netting or biodegradable equal. Biodegradable netting must be used with this option Hardwood stakes shall have dimensions of 1½ in. x 1 ½ in. and sufficient length to provide 2’ embedment into the ground. If a rocky soil is encountered, the stake embedment shal l be approved by the Engineer. 485 (n) Triangular Silt Dikes shall be supported and shall have a height of at least eight to ten inches (8-10”) in t he center with equal sides and a sixteen to twenty inch (16-20”) base. The outer cover shall be a woven geotextile fabric placed around th e inner material and allowed to extend beyond both sides of the tria ngle 24-36 inches. The geotextile fabric shall be mildew resi stant, rot proof and resistant to ultraviolet radiation meeting the requ irements for silt fence in AASHTO M 288. The edges shall be treated to prevent unraveling. Seams and stress points shall be reinf orced. The fabric cover and apron shall be a continuous wrapping of t he fabric: the apron shall be a continuous extension of the upstre am face. The triangular shaped inner material shall be urethane foam. Standard length of each silt dike will be seven feet (7’) un less otherwise indicated on the plans.
621.03 Construction Requirements. (a) General The
Contractor shall actively maintain the areas or ite ms constructed under this subsection from the time of their comple tion until the Engineer determines the items are no longer require d. Additional work and materials required because of loss from er osion or other causes beyond the Contractor's control will be paid for unless they were required due to Contractor's negligence, in wh ich case the maintenance shall be at no cost to the Department. Temporary erosion control items and devices shall b e removed, or may remain in place as directed by the Engineer, after final stabilization has been achieved but must be removed before the Notice of Termination for the Construction Storm Wa ter Permit has been submitted. After items have been removed, the affected areas shall be graded to conform to the adjacent contours , unless otherwise directed by the Engineer. Following this removal a nd grading, permanent stabilization shall be established in the se areas. Disposal, when required, shall be according to the requirements of Sections 110 and 201. Salvageable materials wil l become the property of the Contractor.
b.Temporary Seeding. The area designated or directed to be temporarily seeded does not have to be brought to t ypical section or a garden-like condition, but shall be lightly tille d. Rye or the cereal grasses shall be planted at the r ate of 100 pounds per acre (110 kg/ha) between August 15 and J anuary 20. 486 Brown Top Millet shall be planted at a rate of 50 p ounds per acre (55 kg/ha) between January 21 and August 14. The s eeding mixture may be altered by the Engineer in selected areas wi th no adjustment in contract price. The alteration will be made on an equivalent cost basis. Fertilizer shall be applied at the rate of 500 pounds per acre (560 kg/ha) of 10-20-10 or the equivalent amount of plant food. The Engineer may adjust the seasonal limitations sp ecified above when immediate erosion control measures are require d and other methods are not considered practicable. The decisi on to adjust seasonal limitations will be based on the practical ity of planting seed at that particular time, with consideration being g iven to the geographic location of the project and the period o f time remaining before permanent erosion items can be applied. From April 1 through December 31, either the day be fore the temporary seeding is placed or on the day of the te mporary seeding operation (either before the seed is placed or afte r the application of the mulch cover) an application of water will be ap plied, in accordance with Subsection 620.03(f)(1). No subseq uent weekly waterings will be required for Temporary Seeding. Failure to meet this application of water requireme nt will result in a permanent deduction in payment and /or permanent recovery of payments equal to the minimum bid price established in Subsection 620.05(d) for each M.G. (kL) not applied as directe d in accordance with these specifications. Equipment and methods u sed to place the water shall be in accordance with Subsection 620.03 (f)(4).
c.Mulch cover shall be applied according to Section 6 20.
d.Erosion control matting shall be applied according to Section 626.
e.Bales for baled straw filter barriers shall be ins talled so that the bindings are oriented around the sides of the b ales and not along the tops and bottoms. The bales shall be keyed int o the ground a minimum of 4" (100 mm) and securely held in place b y staking, wiring, and/or other methods that will prevent floa ting and/or displacement. No gaps shall be left between bales. The number of bales required and the specific arrangement of them will vary with the conditions at each site. Bales that become dis placed shall be retrieved and re-installed, if suitable. Bales tha t become 487 unserviceable in their original location shall be r emoved and replaced.
f.Geotextile fabric for silt fence shall be attached to the supporting system in such manner that it will remai n attached and fully supported for the entire time the barrier is needed for service. The fabric toe shall be buried to secure the base a s shown on the plans. Splices shall be securely fastened. Re-anc horing of the toe of the installed silt fence and re-securing the geotex tile fabric to the supports shall be considered normal maintenance and will be considered included in the unit price bid for silt fence. After permanent stabilization has been completed, o r simultaneously with the permanent stabilization, th e silt fence and the silt trapped by it shall be removed and dispose d of as directed by the Engineer. Disposal shall be according to the r equirements of Sections 110 and 201. When directed by the Enginee r, silt fences shall be left in place.
g.For sand bag ditch checks, the sacks shall be fille d approximately 3/4 full, shall weigh a minimum of 55 pounds (25 kg), and shall be securely closed. Sand bags shall be placed in the ditches at locatio ns shown on the plans or as directed by the Engineer. They shall b e laid in horizontal courses and successive courses shall break joints w ith preceding ones. The sacks shall be rammed and packed against each other and tamped on the surface to secure a uniform surface. The overflow area in the center of the ditch check shall be cons tructed lower than the sides. The number of bags required and the arr angement at each installation will vary with on-site conditions.
h.Excavation and grading for diversion ditches shall be according to the dimensions and at the locations sh own on the plans or as directed by the Engineer.
i.Geotextile for drop inlet silt fences shall be atta ched to the supporting system in such manner that it will remai n attached and fully supported for the entire time the barrier is needed for service. The fabric toe shall be buried to secure the base a s shown on the plans. Splices shall be securely fastened. 488 (j) Rock ditch checks shall be constructed as shown on the plans or as directed by the Engineer. The overflow area in the center of the ditch check shall be constructed lower than the sides.
k.Sediment basins shall be constructed to the dimensi ons shown on the plans or as directed by the Engineer. The s oil used in basin construction shall be compacted and stabilized. Du mped riprap and geotextile for a sediment basin with a spillway out let shall be placed on the spillway as shown on the plans. For sedimen t basins with a pipe outlet, the rock filter material shall be plac ed around a perforated riser pipe that is connected with an elb ow to a non- perforated corrugated metal pipe. Sufficient rock filter shall be used to cover the perforations and stabilize the riser. An anti-seep collar shall be installed. Sediment basins shall not be obliterated until fina l stabilization has been achieved. The soil used to create the bas in, the sediment trapped in the basin, and the dumped riprap and roc k filter for the outlet may be used to fill the basin; however, all fill material used shall be compacted and stabilized. The area shall be graded to conform to the adjacent contours, unless otherwise directed by the Engineer.
l.Sediment collected in the various erosion and sedim ent control devices shall be removed when needed and as directe d by the Engineer. Sediment basins and ditch checks shall h ave sediment removed when their capacity is reduced by half. Si lt fences shall have sediment removed when a deposit covers 1/3 the height of the structure. Sediment removed shall be deposited and stabilized as described in Section 110. Sediment will normally b e incorporated back into the embankment construction as directed b y the Engineer.
m.Mulch control netting shall be installed over the m ulch with the longitudinal length parallel to the slope. Adj acent netting widths shall be overlapped by not less than 4" (100 mm). Remaining fabric areas shall be stretched, then secured by pinning t o the ground with approximately 1 staple per square yard (square mete r) of area. Upslope ends, edges, bottom, and overlaps shall be stapled at 2 foot (0.6 meter) intervals.
n.Slope drains shall be constructed as shown on the p lans or as directed by the Engineer. Pipe for slope drains sh all be installed 489 down the slope as shown on the plans and securely h eld in place by anchor stakes or other devices as approved by the E ngineer.
o.Wattles shall be placed on the ground and securely held in place by stakes as shown on the detail sheet. The number of wattles required will vary with the conditions at each site ; therefore, a series of wattles shall either be butted together or overl apped as directed by the Engineer. A continuous segment of wattle shall be used in a ditch application. Accumulated sediment shall be removed when it cover s one-half the height of the wattle. Sediment removed shall b e deposited and stabilized as described in Section 110. Payment fo r this work will be made under the item “Sediment Removal and Dispos al.” Repair of or complete replacement of torn or damaged wattl es shall be performed as required or as directed by the Enginee r. Wattles shall be temporarily removed and replaced as required to facilitate construction operations. When the required work has been completed and the a rea has been stabilized and approved by the Engineer, the w attle netting is to be cut and the core material shall be spread out on the surrounding ground area. If non-biodegradable netting is used in the wattles, the netting shall be removed from the site. If biodegr adable netting is used, it can remain in place under the organic core material. Upon completion of the spreading of the core material, t he area is to be approximately level so that no barrier to water flo w will exist.
p.Install, align, and locate the triangular silt dike s as shown on the plans, or as directed by the Engineer. All tri angular silt dikes shall be placed on the contour and in a row with en ds tightly abutting the adjacent triangular silt dike. Filter material shall lap over the ends 6 inches to cover dike to dike juncti ons; each junction shall be secured with wire staples. The approach apron shall be followed by the sewn se am and front side of the dike section. The exiting apron will l ie underneath the dike section and extend out beyond the discharge si de. When triangular silt dikes are installed across sur face drainage ditches, the highest point of the triangular silt d ike in the center of the ditch must be lower than the lowest point of th e triangular silt 490 dike at the end. This will direct water over the c enter of the triangular silt dike and not around the ends. When installed as diversion devices, triangular sil t dikes shall be placed along the contour or on a 1-2% gradient to a planned discharge point. Accumulated sediment shall be removed when it cover s one half the height of the triangular silt dike. During rem oval of sediment, the operator must exercise care within the range of the front apron to avoid damage to the device. The range of the apron is approximately eighteen to twenty four inches (18-24 ”) from the base of the barrier. Sediment removed shall be deposite d and stabilized as described in Section 110. Payment for this work will be made under the item “Sediment Removal and Disposal.” Inspect all triangular silt dikes after each rainfa ll event and/or each seven day period. Triangular silt dikes shall be temporarily removed and replaced as required to facilitate cons truction operations. Any deficiencies or damage shall be re paired at no cost to the Department. Repair of, or complete replacem ent of torn or damaged triangular silt dikes shall be performed as required or as directed by the Engineer at no additional cost to t he Department.
621.04 Method of Measurement. (a) Temporary Seeding will be
measured by the acre (hectare) of actual area cover ed.
b.Mulch Cover will be measured according to Section 6 20.
c.Erosion Control Matting will be measured according to Section 626.
d.Baled Straw Filter Barriers will be measured by th e bale in place as authorized by the Engineer.
e.Silt Fence will be measured by the linear foot (me ter) complete in place.
f.Sand Bag Ditch Checks will be measured by the bag.
g.Diversion Ditches will be measured by the linear fo ot (meter).
h.Sediment Basins will be measured by the cubic yard (cubic meter) of volume contained in the basin below the s pillway elevation or the top of the riser pipe. This volume will be calculated by measuring the length, width, and average depth or b y using the 491 average end area method. Dumped riprap, geotextile , and rock filter for spillway outlets will be measured according to Sections 816, 625, and 207 respectively. Pipe for sediment basins wil l be measured by the linear foot (meter) along the center of the pip e and will include riser, elbow, and pipe outlet. Rock filter for sed iment basins will be measured by the ton (metric ton). Obliteration of Sediment Basin will be measured by the cubic yard (cubic meter). The quantity for purposes of p ayment will be the same quantity as was determined for the original co nstruction of the basin, and no further measurement will be made.
i.Drop Inlet Silt Fence will be measured by the line ar foot (meter) in place along the midpoint in height of th e outside perimeter of the completed structure.
j.Rock Ditch Checks will be measured by the cubic yar d (cubic meter) in place. The volume will be calculated by measuring the average length, width, and depth or by using the av erage end area method.
k.Sediment Removal and Disposal will be measured by t he cubic yard (cubic meter) of sediment removed. The volume will be calculated by measuring the length, width, and the average depth or by using the average end area method.
l.Mulch Control Netting will be measured by the squar e yard (square meter) of actual area covered.
m.Dumped Riprap for slope drains will be measured acc ording to Section 816. Pipe for slope drains will be meas ured by the linear foot (meter) along the center of the pipe and will include elbows and tees.
n.Water will be measured according to Section 620.
o.Wattles will be measured by the linear foot complet e in place; measurement will be made along the centerline of th e top of each wattle. The overlap length will be paid for at the contract unit price.
p.Triangular Silt Dikes will be measured by the linea r foot, complete in place, with measurement being made alon g the centerline of the top of the barrier. 492 621.05 Basis of Payment. (a) Temporary seeding completed and accepted and measured as provided above will be pai d for at the contract unit price bid per acre (hectare) for Temp orary Seeding.
b.Mulch cover will be paid for under Section 620.
c.Erosion control matting will be paid for under Sect ion 626.
d.Baled straw filter barrier completed and accepted and measured as provided above will be paid for at the contract unit price bid per bale for Baled Straw Filter Barrier.
e.Silt Fence completed and accepted and measured as provided above will be paid for at the contract unit price b id per linear foot (meter) for Silt Fence.
f.Sand bag ditch checks completed and accepted and me asured as provided above will be paid for at the contract unit price bid per bag for Sand Bag Ditch Checks.
g.Diversion ditches completed and accepted and measur ed as provided above will be paid for at the contract uni t price bid per linear foot (meter) for Diversion Ditch.
h.Sediment basins completed and accepted and measured as provided above will be paid for at the contract uni t price bid per cubic yard (cubic meter) for Sediment Basins. Dump ed riprap and geotextile for sediment basins will be paid for und er Sections 816 and 625 respectively. Pipe culvert for sediment ba sins completed and accepted and measured as above will be paid for at the contract unit price bid per linear foot (meter) for Pipe Cul vert for Sediment Basins. Rock filter for sediment basins completed accepted and measured as provided above will be paid for at the contract unit price bid per ton (metric ton) for Rock Filter for Sediment Basins. Obliteration of sediment basin completed and accept ed and measured as provided above will be paid for at the contract unit price bid per cubic yard (cubic meter) for Oblitera tion of Sediment Basin, which price shall be full compensation for a ll work required to obliterate the sediment basin including furnishi ng, placing and compacting fill material; seeding; and applying mul ch cover to the area. 493 (i) Drop inlet silt fence completed and accepted and me asured as provided above will be paid for at the contract uni t price bid per linear foot (meter) for Drop Inlet Silt Fence.
j.Rock ditch checks completed and accepted and measur ed as provided above will be paid for at the contract uni t price bid per cubic yard (cubic meter) for Rock Ditch Checks.
k.Work involved in the removal and disposal of sedime nt from erosion and sediment control devices completed and accepted and measured as provided above will be paid for at the contract unit price bid per cubic yard (cubic meter) for Sediment Removal and Disposal.
l.Mulch control netting completed and accepted and me asured as provided above will be paid for at the contract unit price bid per square yard (square meter) for Mulch Control Nettin g.
m.Dumped riprap for slope drains will be paid for und er Section 816. Pipe for slope drains completed and a ccepted and measured as provided above will be paid for at the contract unit price bid per linear foot (meter) for Pipe for Slop e Drains.
n.Water will be paid for under Section 620. A perma nent deduction in payment and/or permanent recovery of p ayments equal to the minimum bid price contained in Subsection 62 0.05(d) will be made as an item deduction for each M.G. (kL) not ap plied as directed in accordance with these specifications. W ater used for hydro-seeding will not be paid for separately, but full compensation therefor will be considered included in the contrac t unit price bid for Temporary Seeding.
o.Wattles completed and accepted and measured as prov ided above will be paid for at the contract unit price b id per linear foot for Wattle, which price shall be full compensation for furnishing all materials; for initial wattle installation, includi ng hardwood stakes (installation and removal); for routine inspection and maintenance of wattles; for temporarily removing and replacing wat tles as required to facilitate construction operations; for removing the wattles (if directed); and for all labor, equipment, tools, and incidentals necessary to complete the work.
p.Triangular Silt Dike work completed and accepted un der this item and measured as provided above will be paid fo r at the contract 494 unit price bid per linear foot for Triangular Silt Dike, which price shall be full compensation for furnishing, placing, maintaining, temporarily removing and replacing as required to f acilitate construction operations, and removal of the Triangu lar Silt Dike and for all other materials, labor, tools, equipment, a nd incidentals necessary to complete the work. The contract unit prices mentioned above shall be f ull compensation for furnishing all materials; for site preparation; for acceptable maintenance of the completed items; for subsequent removal of the items when applicable; for permanent stabilization of the areas disturbed by the removal of these items, and for all labor, equipment, tools, and incidentals necessary to comp lete the work. Other temporary erosion control measures may be ord ered by the Engineer to establish control of soil erosion or se dimentation. These items will be measured and paid for according to th e applicable portions of these specifications. Payment will be made under: Pay Item Pay Unit Temporary Seeding Acre (Hectare) Baled Straw Filter Barrier Bale Silt Fence Linear Foot (Meter) Sand Bag Ditch Checks Bag Diversion Ditch Linear Foot (Meter) Drop Inlet Silt Fence Linear Foot (Meter) Rock Ditch Checks Cubic Yard (Cubic Meter) Sediment Basin Cubic Yard (Cubic Meter) Rock Filter for Sediment Basin Ton (Metric Ton) Pipe Culvert for Sediment Basin Linear Foot (Meter) Obliteration of Sediment Basin Cubic Yard (Cubic Me ter) Sediment Removal and Disposal Cubic Yard (Cubic Met er) Mulch Control Netting Square Yard (Square Meter) Pipe for Slope Drains Linear Foot (Meter) Wattle (_”) Linear Foot (Meter) Triangular Silt Dike Linear Foot (Meter) 495 SECTION 622 SOD MULCH
622.01 Description. This item shall consist of furnishing and
applying lime, fertilizer, sod mulch, seed and mulc h cover when required, and water according to these specificatio ns at locations shown on the plans, or as directed. The work under this item shall be accomplished as s oon as practicable after the grading in an area has been c ompleted in order to deter erosion of the roadway and siltation of st reams.
622.02 Materials. (a) Lime shall comply with Subsection
620.02(a).
b.Fertilizer shall comply with Subsection 620.02(b).
c.Sod mulch shall consist of cuttings and root system s of live, growing Bermuda grass and shall be procured from ar eas where the soil is fertile as indicated by vigorous growth. T he grass shall have a healthy virile root system of dense, thickly matted roots throughout the sod for a thickness of at least 3 inches (75 mm ). The sod shall be reasonably free from noxious weeds or undesirable g rasses and shall not contain any matter injurious to its growth or h ardiness when transplanted. All sources of sod mulch shall be ap proved by the Engineer.
d.Seed for overseeding sod mulch shall comply with Su bsection 620.02(c).
e.Mulch cover for overseeding sod mulch shall comply with Subsection 620.02(d).
f.Tackifiers for mulch cover shall comply with Subsec tion 620.02(e).
g.Water shall be according to Subsection 620.02(f).
622.03 Construction Requirements. (a) Preparation o f Areas
Receiving Sod Mulch. The areas to be sodded shall be brought to a reasonably smooth and uniform surface to conform to the finished grade and cross section shown on the plans. If the plans call for the item replacing topsoil, this shall be done before a ny other preparations for receiving sod mulch. 496 The area shall be thoroughly pulverized by means of disk harrows or other approved methods to a depth of not less th an 3" (75 mm). Regardless of the pulverizing method used, the soil shall be broken with the contour of the slope. In areas consisting of shale or rock fragments, disking will be waived but lateral furro ws 2" to 3" (50 mm to 75 mm) deep at 36" (1 m) intervals shall be c onstructed with the contour of the slope and sod mulch placed to pr ovide a uniformly smooth surface susceptible to being mowed. Objectionable foreign matter shall be removed and t he soil left in a suitable horticultural condition to receive the s od mulch. Water may be applied before, during, and after prep aration as directed by the Engineer to maintain the desired mo isture content in the soil. Watering shall be according to Section 6 20.
b.Preparation of Areas Producing Sod Mulch. The area from which sod mulch is to be secured shall be clos ely mowed and raked to remove all weeds and long standing stems. This operation may be dispensed with at the discretion of the Engi neer when the grass source has been pastured, or for any other re ason is free of weeds, long standing stems, or other debris. Before disking the mulch, soil samples shall be obt ained from each major soil area or sod field by the Engineer f or lime requirement analysis. On the basis of soil analysis tests, lime shall be applied at 1/3 the rate determined per hectare (acre) by the lime requ irement test for each 1" (25 mm) of depth sod mulch is excavated. Fertilizer shall be applied at the rate of 270 poun ds per acre (300 kg/ha) of 10-20-10, or the equivalent amount o f plant food, for each 1" (25 mm) of depth sod mulch is to be excavat ed. After mowing and raking, the required lime and fert ilizer shall be uniformly spread over the sod mulch area. The gras s shall then be disked thoroughly until the sod has been well mixed with lime and fertilizer to the depth the sod mulch is to be remo ved. Sod mulch shall be excavated to a minimum depth of 3" (75 mm) and to a maximum depth of 6" (150 mm). Immediately after di sking, the sod mulch shall be cast into windrows. Care shall be e xercised that only topsoil is included in the material excavated with the sod. 497 The sod mulch shall be procured only when the soil is in a moist, friable condition.
c.Method of Placement. Sod mulch shall not be cut in the Spring until the Bermuda grass begins to show growt h. Sod Mulch shall be hauled and placed before reduced viability has taken place. The sod mulch shall be spread uniformly upon the pr epared area to the required approximate depth shown on the plans o r directed by the Engineer. After the sod mulch has been spread and shaped, the entire area shall be satisfactorily compacted by use of rollers , cultipackers, or other approved equipment. Any section not true to lines and typical cross section shall be corrected by the addition of sod material or by reshaping the materials previously placed. The sod mulch shall be thoroughly watered immediate ly after being placed. The Contractor shall maintain growth areas from time of placement for a period of at least 3 weeks or un til final acceptance of the project, whichever is greater. The time req uired for watering grass will not be included in computations for time required to complete the project provided all other work under the Contract has been completed. Additional watering to encourage g rowth beyond the 3-week period shall be applied as directed.
d.Restoration. Additional work and materials required because of loss through erosion will be paid for under the pertinent contract items. Additional work and materials required due to the Contractors negligence in maintaining completed wor k shall be accomplished at no cost to the Department. The sod mulch source field shall be finished according to the agreement between the Contractor and Owner. A copy of the agreement will be provided to the Engineer before sod is removed. The agreement will stipulate the final condition of the source field. All resto ration of the source field shall be done at no cost to the Department.
e.Overseeding. Sod mulch placed after July 31 shall be overseeded as soon after placement as possible with in the seasonal limitations specified in Subsection 620.02(c). If packing or hardening of the sod mulch has occurred prior to th e time of overseeding, a surface preparation of light harrowi ng or other method approved by the Engineer shall be applied be fore seeding. No fertilizer will be applied to the areas requirin g overseeding. The 498 applicable requirements of Subsections 620.03(c), ( d), (e), and (f) shall govern the construction methods for overseedi ng.
622.04 Method of Measurement. (a) Lime will be measured
according to Section 620.
b.Sod Mulch will be measured by the cubic yard (cubic meter) in approved vehicles at the point of delivery on th e road. At the Contractor's option, solid sodding complying with Section 624, may be substituted for sod mulch. Measurement will be made at the planned rate of sod mulch over the actual ar ea covered by solid sodding.
c.Overseeding Sod Mulch will be measured by the acre (hectare) of actual area covered.
d.Mulch Cover will be measured according to Section 6 20.
e.Water will be measured according to Section 620.
622.05 Basis of Payment. (a) Lime will be paid for under
Section 620.
b.Sod mulch completed and accepted and measured as pr ovided above will be paid for at the contract unit price b id per cubic yard (cubic meter) for Sod Mulch, which price shall be f ull compensation for preparing the areas receiving and the areas pro ducing sod mulch; for furnishing fertilizer and sod mulch material; f or hauling, spreading, finishing, and maintaining; and for all labor, equipment, tools, and incidentals necessary to complete the wo rk.
c.Overseeding sod mulch completed and accepted and me asured as provided above will be paid for at the contract unit price bid per acre (hectare) for Overseeding Sod Mulch, which pri ce shall be full compensation for needed seedbed preparation; for fu rnishing and applying seed; and for all labor, equipment, tools, and incidentals necessary to complete the work.
d.Mulch cover will be paid for under Section 620.
e.Water will be paid for under Section 620. Water fo r moistening the sod field and for hydro-seeding will not be paid for separately, but full compensation therefor will be considered included in the contract unit prices bid for Sod Mu lch and Overseeding Sod Mulch. 499 Payment will be made under: Pay Item Pay Unit Sod Mulch Cubic Yard (Cubic Meter) Overseeding Sod Mulch Acre (Hectare)
Source: , Edition.