Part 642
2. Install terraces, diversions, or level spreaders, including stable outlets:
(a) Above and below borrow areas (b) Above earth emergency spillways (c) Above storage areas
3. Control access and haul roads:
(a) Contour roads and grade surfaces away from slopes and toward controlled outlets.
(b) Dust control with water and/or chemicals.
(c) Erosion control by installing turnouts and culverts and by stabilizing road ditches.
(d) Vegetate disturbed areas.
(e) Surface roughening or pitting.
4. Shape and control borrow areas. Reduce area and duration of exposed areas.
5. Install debris basins, brush dams, straw bale barriers, and geotextile fences.
6. Locate, shape, size, and protect by-pass chan-nel:
— Use coffer dams.
— Pump extra water across construction area.
7. Sectional construction.
8. Timely installation of all structural and stabili-zation practices.
9. Control work sequence.
10. Complete as you go.
11. Winter or seasonal shutdowns to minimize pollution control problems.
12. Good housekeeping practices, to prevent water or air pollution, in use at the work site at all times.
13. Seeding for temporary or permanent protec-tion. Provide topsoil as appropriate.
14. Prevent wildfires. Burn only per regulations.
15. Prevent pollution by chemicals and lubri-cants.
16. Mulch unprotected areas.
Channels
1. Preserve natural vegetation where possible.
Remove blocks if possible.
2. Leave old channel to function as long as pos-sible. Perform new channel excavation as an initial construction activity.
3. Where possible, do not open new channel to flows until vegetation is established. Sequence work.
4. Seed or sod slopes immediately after con-struction. Provide topsoil as necessary.
5. Mulch or mat slopes immediately after distur-bance.
6. Spray mulch, seed, fertilizer, and asphalt or polyvinyl resin.
7. Begin excavation downstream and work up-stream.
8. Use temporary grade control structures.
9. Limit clearing, clearing and grubbing, and snagging.
10. Limit disturbance of channel banks to one side. Delay and complete other side after the initial side is vegetated.
11. Channel construction should be performed in segments, completing each segment before starting the next.
12. Control storm water inlets into channel.
13. Install pipe inlets, grade control structures, and other such structures at the time of con-struction.
14. Install sediment traps in channel and provide for their cleanout and maintenance.
5. Methods
Section 7, Measurement and payment
Method 1—Provides measurement and payment by the unit of work performed. The use of water and chemical suppressants inappropriately and in exces-sive to need may be clarified in section 8.
Method 2—Provides for payment on the lump sum ba-sis with progress payments determined from invoices provided by the contractor.
Part 642
National Engineering Handbook National Standard Construction
Specifications Chapter 2
Method 3—Provides for payment on the lump sum basis with measurement on a prorated and equal basis for each monthly payment.
When specifications are prepared using electronic procedures and all methods but one are deleted for use in the contract specification, delete from the last paragraph, All Methods—The following provisions apply to all methods of measurement and pay-ment. Left justify the remaining text.
6. Items of work and construction details Starting at the top of page 5–3, prepare and outline job specific "Items of Work and Construction Details"
(IWCD) in accordance with these instructions.
Part 642
National Engineering Handbook National Standard Construction
Specifications Chapter 2
(210–VI–NEH, January 2009) 5–I–4
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
All material furnished shall meet the requirements of the material specifications listed in section 8 of this specifica-tion.
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 8 of this specification or required by Federal, State, or local government.
4. Chemical pollution
The contractor shall provide watertight tanks or barrels or construct a sump sealed with plastic sheets to collect and temporarily contain 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. Pollutants shall be disposed of in accordance with appropriate State and Federal regulations. At the completion of the construction work, tanks, barrels, and sumps shall be removed and the area restored to its original condition as specified in sec-tion 8 of this specificasec-tion. Sump removal shall be conducted without causing pollusec-tion.
Construction Specification 5—Pollution Control
5–2 (210–VI–NEH, January 2009)
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 comple-tion of construccomple-tion activities, facilities shall be disposed of without causing pollucomple-tion as specified in seccomple-tion 8 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 1—For items of work for which specific unit prices are established in the contract, each item is measured to the nearest unit applicable. Payment for each item is made at the contract unit price for that item. For water or chemical suppressant items used for dust control for which items of work are established in section 8 of this speci-fication, measurement for payment will not include water or chemical suppressants that are used inappropriately or excessive to need. Such payment will constitute full compensation for the completion of the work.
Method 2—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 price 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 compensa-tion for complecompensa-tion of the work.
Method 3—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 pro-rating 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.
All Methods—The following provisions apply to all methods of measurement and payment. Compensation for any item of work described in the contract, but not listed in the bid schedule is included in the payment for the item of work to which it is made subsidiary. Such items, and the items to which they are made subsidiary, are identified in section 8 of this specification.
8. Items of work and construction details
Part 642