Section 2602. Water Pollution Control (Soil Erosion)
A. Temporary control measures for projects to control water pollution caused by soil erosion. Additional measures are described in Section 2601.
B. Projects that are regulated by the requirements of Iowa DNR National Pollutant Discharge Elimination System (NPDES), General Permit No. 2, for Storm Water Discharge Associated with Industrial Activity for Construction Activities, will be identified in the contract documents. The Prime Contractor for these projects will be required to complete, sign, and return, along with the signed contract, a certification statement for storm water discharge associated with industrial activity for construction activities. Affected Subcontractors for the project will be required to sign and return an affidavit identifying them as co-permittees with the Contracting Authority prior to starting work.
C. Coordinate temporary water pollution control work with permanent erosion control work to ensure economical, effective, and continuous erosion control throughout the construction and post construction period.
D. Water Pollution Control Quality Control.
1. For projects regulated by a NPDES storm water permit:
a. Designate a Water Pollution Control Manager (WPCM) from the Contractor prior to initiating any construction activities. The WPCM shall:
1) Complete Iowa DOT Erosion & Sediment Control Basics (ESC Basics) web-based training (which is valid for 2 years) or Erosion Control (ECT) certification (which is valid for 5 years through the Technical Training and Certification Program of the Department);
2) Be authorized by the Contractor and have the authority to supervise all work performed by the Contractor and subcontractors that involves storm water requirements or affects storm water compliance;
3) Be authorized by the Contractor and have the responsibility to order the Contractor’s employees and subcontractors to take appropriate corrective action to comply with storm water requirements, including requiring any such person to cease or correct a violation of storm water requirements and to order or recommend such other actions or sanctions as necessary to meet storm water requirements,
4) Be familiar with the Project Pollution Prevention Plan (PPP);
5) Be the point of contact for Contracting Authority regarding storm water compliance;
6) Be responsible for reviewing and signing or delegating review and signing of inspection reports to a trained or certified individual from the Contractor, acknowledging awareness of any deficiencies and ensuring the correction of all deficiencies; and
7) Visit the Project on a frequent basis and in no instance less than once per week during construction activities. When the Contractor is not mobilized onsite, the Contractor may delegate this responsibility to a subcontractor.
b. Maintain an individual that will be onsite daily during construction activities. This individual shall have completed at a minimum ESC Basics training. This individual shall be responsible for coordinating all erosion and sediment control operations. For this daily requirement, the Contractor may subcontract this responsibility.
1) Additional responsibilities of an ESC Basics trained individual that shall not be subcontracted include:
· Attend required storm water inspections with the Contracting Authority. However, when the Contractor is not mobilized onsite, the Contractor may delegate this responsibility to a subcontractor.
· Prepare required initial Erosion Control Implementation Plan (ECIP) submittal and ECIP updates.
· Attend construction progress meetings to discuss erosion and sediment control issues.
2) Contractor’s WPCM may fulfill these responsibilities.
c. Maintain an Erosion Control Technician (ECT) on staff, even though the erosion and sediment control portion of the contract may be subcontracted. This individual shall be responsible for overall management of Contractor’s quality control program for erosion and sediment control. Contractor’s WPCM may fulfill these responsibilities if ECT certified.
2. For projects regulated by a NPDES storm water permit and where the Department is the Contracting Authority, the Department may use Permix, a web-based software application, to record storm water permit compliance information.
a. Project and permit set-up will be performed by the Department.
b. Contractor shall be responsible for:
· Managing its own company users and adding subcontractor companies.
· Uploading Erosion Control Implementation Plan and amended PPP documents.
· Uploading subcontractor co-permittee certifications.
· Reviewing and signing inspection reports (if not already signed in the field).
c. If Permix is not used on a project, the above referenced documents shall be uploaded to or signed in DocExpress per Section 1113.
d. Costs associated with the use of Permix are incidental to Mobilization.
3. For projects regulated by a NPDES storm water permit, submit an amended PPP site map that identifies erosion and sediment control work performed. Submittal is required prior to payment for corresponding erosion and sediment control contract items from Sections 2601 and 2602, but shall be submitted no later than one week after installation of such items. Submittal of amended PPP site map shall be incidental to payment for erosion and sediment control items.
Use materials complying with Division 41.
A. For projects regulated by a NPDES storm water permit, prior to the preconstruction conference furnish the Engineer an initial ECIP for accomplishment of temporary and permanent erosion and sediment control.
In the ECIP, include stages for erosion and sediment control work to address Contractor’s timetable and sequence for major activities or stages on the contract. ECIP stages shall consider as a minimum:
• Initial controls required prior to land disturbing activities,
• Intended timetable and sequence of major land disturbing activities,
• Construction staging to limit disturbed areas,
• Sensitive areas requiring special consideration,
• Anticipated suspension of work and stabilization of disturbed areas,
• Compliance with Pollution Prevention Plan (PPP), and
• Method of erosion control on haul roads.
B. Obtain the Engineer’s acceptance for the ECIP and methods before commencing work. Schedule and perform all operations so erosion control features are placed according to accepted ECIP. Update ECIP as needed to address changes in schedule of operations or staging, weather changes, or other changes required in order to comply with applicable permit requirements.
C. Provide immediate, permanent or temporary, water pollution control measures to prevent contamination of adjacent watercourses and property. This work may involve:
· Constructing or installing silt fence, silt fence for ditch checks, silt ditches, silt dikes, silt basins, and slope drains,
· Constructing or installing perimeter and slope sediment control devices (straw wattles, wood excelsior logs, or filter socks filled with compost filter material), and
· Using temporary mulches, mats, seeding, or other control devices or methods, as necessary to control erosion and sediment pollution.
D. Unless otherwise specified, use compost as a filter medium in filter socks, filter berms, or filter blankets for sediment control.
E. For projects regulated by an NPDES storm water permit, initiate stabilization of disturbed areas immediately after clearing, grading, excavating, or other earth disturbing activities have:
• Permanently ceased on any portion of site, or
• Temporarily ceased on any portion of site and will not resume for a period exceeding 14 calendar days.
Stabilization measures include temporary seeding, permanent seeding, mulching, sod, or other methods the Engineer approves.
F. Incorporate all erosion control features into the project at the earliest practical time, as outlined in the accepted schedule. Construct water pollution control measures:
· At locations shown in the contract documents and as determined by the Contractor,
· At locations where conditions develop during construction that were unforeseen during design, or
· Where needed to control water pollution that develops during normal construction practices.
G. Maintain water pollution control features in appropriate functional condition from initial construction through completion of the project. Restore siltation control features to their original condition where siltation has reduced their capacity by 50% or more.
H. Maintenance of Silt Fence and Silt Fence for Ditch Check includes excavation and disposal of silt material trapped by the silt fence or silt fence for ditch checks. Shaping of the ditch bottom to the original ditch template is incidental to this item. Dispose of the silt material off the project unless Engineer approves a suitable site within the project limits.
Maintenance also includes repair of silt fence due to undermining, leaning, or fabric becoming unattached from posts. Repair requiring new fabric will be paid for under type of silt fence properly installed and will not be considered maintenance.
I. Limit clearing and grubbing, excavation, borrow, and embankment operations in progress to an area commensurate with their capability. Progress in keeping the finish grading, mulching, seeding, and other pollution control measures current according to the accepted work schedule. The Engineer may suspend operations if the Contractor fails to provide adequate erosion control measures in a timely manner.
J. In the event of conflict between these requirements and water pollution control laws, rules, or regulations of other Federal, State, or local agencies, the more restrictive laws, rules, or regulations will apply.
K. The Contractor is responsible for water pollution control for work outside the right-of-way or easement obtained by the Contracting Authority.
L. Mobilizations, Erosion Control.
1. Mobilizations, Erosion Control, applies to projects not identified as erosion control or landscaping and contain a Storm Water Pollution Prevention Plan (SWPPP).
2. Only one mobilization will be paid for each stage of work described in the ECIP. Within the scope of work defined for each single mobilization described in the ECIP, additional movement due to weather delays or at the option of the Contractor will not be counted as a mobilization.
3. Separate mobilizations needed for different crews performing work such as silt fence, seeding, or ditch checks will be counted, however, multiple mobilizations will not be paid for a single crew performing different items of erosion control work.
4. Payment for mobilization applies to contract items from Sections 2601 and 2602, excluding watering, mowing, debris pickup, monitoring well, or removal items.
5. Additional mobilizations not outlined in the ECIP must be approved by the Engineer.
6. Payment for mobilization to correct items not properly installed will not be approved. Payment for mobilization will also not be approved if labor, equipment, and materials to perform erosion control are used for other non-erosion control work onsite.
7. Mobilize within 72 hours of a written order with sufficient labor, equipment, and materials to perform erosion and sediment control work included in ECIP or PPP, or as ordered or approved by Engineer. Complete work within 7 calendar days of a written order.
8. Failure to mobilize and complete work within such time period, will result in a deduction of $750.00 per calendar day from payment due under the contract, except when Engineer extends such time period.
9. Mobilizations, Erosion Control, will not include work provided under the item of Mobilizations, Emergency Erosion Control.
M. Mobilizations, Emergency Erosion Control.
Mobilizations, Emergency Erosion Control, applies to projects not identified as erosion control or landscaping and containing a Storm Water Pollution Prevention Plan (SWPPP).
An emergency will be considered to be a sudden occurrence of a serious and urgent nature which is beyond normal maintenance of erosion control items. Emergency work requires immediate mobilization and movement of necessary labor, equipment, and materials to the emergency site, followed by immediate installation of temporary erosion control measures.
1. Mobilize with sufficient labor, equipment, and materials on job site within eight hours of Engineer’s written order to install temporary erosion control items on an emergency basis. Engineer’s written order will include a description of required work. Only one mobilization will be paid for work described in the written order.
2. Failure to mobilize within eight hours of written order, will result in a deduction of $1500.00 per calendar day from payment due under the contract, except when Engineer extends such time period.
N. Removal of Silt Basins.
Fill silt basin with Class 10 material and a minimum of 4 inches of topsoil. Furnish Class 10 material according to Section 2107 and compact by driving over a minimum of two times. Furnish and place topsoil according to Section 2105. Smooth surface of topsoil and leave in a finished condition that drains properly.
2602.04 Method of Measurement.
Measurement for water pollution control items will be as follows:
Linear feet to the nearest 0.1 foot.
Linear feet to the nearest 0.1 foot.
C. Silt Fence for Ditch Checks.
Linear feet to the nearest 0.1 foot.
Linear feet to the nearest 0.1 foot.
By count for each silt basin.
F. Removal of Silt Fence or Silt Fence for Ditch Check.
Linear feet to the nearest foot.
By count for each silt basin removed.
H. Maintenance of Silt Fence or Silt Fence for Ditch Check.
Linear feet to the nearest foot.
I. Perimeter and Slope Sediment Control Device.
Linear feet to the nearest foot of each size.
J. Removal of Perimeter and Slope Sediment Control Device.
Linear feet to the nearest foot.
K. Mobilizations, Erosion Control.
By count for each mobilization in the accepted ECIP and acceptably performed, as well as additional mobilizations ordered or approved by Engineer and acceptably performed. For multi-project contracts, count will be on a per project basis, except for projects where limits are overlapping or contiguous.
L. Mobilizations, Emergency Erosion Control.
By count for each mobilization directed in writing by Engineer and acceptably performed.
N. Rock Check Dam.
Linear feet to the nearest 0.1 feet.
O. Maintenance of Rock Check Dam.
By count.
P. Removal of Rock Check Dam.
By count.
Q. Temporary Sediment Control Basin.
By count.
R. Maintenance of Temporary Sediment Control Basin.
By count.
S. Removal of Temporary Sediment Control Basin.
By count.
T. Open-throat Curb Intake Sediment Filter.
Feet to the nearest foot.
U. Maintenance of Open-throat Curb Intake Sediment Filter.
By count.
V. Removal of Open-throat Curb Intake Sediment Filter.
By count.
W. Stabilized Construction Entrance.
Linear feet measured along the length of the entrance at the entrance centerline
A. Payment for water pollution control items will be the contract unit price as described below. Payment for construction of water pollution control items is full compensation for labor, equipment and materials necessary to construct the items according to the contract documents.
1. Silt Ditches.
Per linear foot for the length of silt ditches properly constructed.
2. Silt Fence.
Per linear foot for the length of silt fence properly installed.
3. Silt Fence for Ditch Checks.
Per linear foot for the length of silt fence for ditch checks properly installed.
4. Silt Dikes.
Per linear foot for the length of silt dikes properly constructed.
5. Silt Basins.
Each for properly constructed silt basins.
6. Removal of Silt Fence or Silt Fence for Ditch Check.
Per linear foot for the length of silt fence or silt fence for ditch check properly removed.
7. Removal of Silt Basins.
Each. Payment is full compensation for providing, preparing, transporting, and placing Class 10 material and topsoil. Contractor has the option, at no additional cost to the Contracting Authority, of stripping and stockpiling Class 10 material and topsoil from constructing silt basins for later use in silt basin removal. Overhaul will not be paid for this item.
8. Maintenance of Silt Fence or Silt Fence for Ditch Check.
Per linear foot for silt fence or silt fence for ditch check properly cleaned out or repaired.
9. Perimeter and Slope Sediment Control Device.
Per linear foot for length of device of each size properly installed.
10. Removal of Perimeter and Slope Sediment Control Device.
Per linear foot for the length of device removed.
11. Rock Check Dam.
Per linear foot. Payment is full compensation for all materials, labor, and equipment required to construct the Rock Check Dam. Class 10 excavation required to cut trench and engineering fabric installed prior to placing revetment are incidental and will not be paid for separately.
12. Maintenance of Rock Check Dam.
Each occurrence. Payment is full compensation for clean out and disposal of material when capacity reaches 50%, and for any repair that is needed during the project.
13. Removal of Rock Check Dam.
Each. Payment is full compensation for all labor and equipment required to remove all rock and material above original ditch grade. Rock, silt, and engineering fabric that is flush with and/or below final ditch grade will be allowed to remain in the excavation trench.
14. Temporary Sediment Control Basin.
Each. Payment is full compensation for furnishing all equipment, labor, and materials required to construct the Temporary Sediment Control Basin as shown.
15. Maintenance of Temporary Sediment Control Basin.
Each occurrence. Payment is full compensation for clean out and disposal of material when capacity reaches 50%, and for any other repair needed during the project.
16. Removal of Temporary Sediment Control Basin.
Each. Payment is full compensation for all labor and equipment required to remove all rock and material above designed ditch grade and to place topsoil. Rock and engineering fabric that is flush with and/or below designed ditch grade will be allowed to remain in place.
17. Open-throat Curb Intake Sediment Filter.
Per foot. Payment is full compensation for furnishing all equipment, labor, and materials required to install the Open-throat Curb Intake Sediment Filter as shown.
18. Maintenance of Open-throat Curb Intake Sediment Filter.
Each occurrence. Payment is full compensation for clean out and disposal of material when sediment accumulation depth reaches 2 inches, and for any other repair needed during the project.
19. Removal of Open-throat Curb Intake Sediment Filter.
Each. Payment is full compensation for all labor and equipment required for removal.
20. Stabilized
Construction Entrance.
Per linear foot. Payment is full compensation for
furnishing all materials and work necessary for installation, maintenance, and
removal of stabilized construction entrance. Maintenance includes installing
additional material or cleaning required to maintain the entrance in a
functional condition.
B. Payment for Mobilizations, Erosion Control, and Mobilizations, Emergency Erosion Control, will be at unit prices stipulated in the proposal. If bid items are not included in the proposal then mobilizations for erosion control will paid at unit prices stipulated below. Mobilization for Erosion Control costs are not included as part of the contract item for "Mobilization" described in Section 2533.
1. Mobilizations, Erosion Control.
The quantity will be paid for at the unit price of $500.00 each for Mobilizations, Erosion Control, which is full compensation for staged movement of labor, equipment, and materials; and labor, tools, equipment, and incidentals necessary to complete the movement.
2. Mobilizations, Emergency Erosion Control.
The quantity will be paid for at the unit price of $1000.00 each for Mobilizations, Emergency Erosion Control, which is full compensation for movement of labor, equipment and materials; and for labor, tools, equipment, and incidentals necessary to complete the movement.
C. When it is necessary for the Contractor to clean out, repair, or reconstruct a silt ditch, dike, or basin, the additional payment will be 100% of the contract unit price for construction of that item. When applicable bid items are not in the contract documents, payment for clean out, repair, or reconstruction will be according to Article 1109.03, B.
D. If water control measures are required due to the Contractor's negligence, carelessness, or failure to install the controls as a part of the work as scheduled, and are ordered by the Engineer, perform this work at no additional cost to the Contracting Authority.
E. All water pollution control features are to be in functional condition before final acceptance of the contract.