669POST-EMERGENT HERBICIDE TREATMENT

576

Spraying will not be permitted when, in the opinion of the Engineer, soil, vegetation, and/or weather conditions are such that the right-of-way or the vegetation would be damaged or spraying would be ineffective. The Contractor shall spray as close as practicable to all fixed objects, exercising extreme care not to damage trees, plants, shrubs, signs, delineators or other appurtenances which are part of the facility. Any damage caused by the Contractor’s spraying operations to any tree, plant, shrub, sign, delineator or other appurtenance which is part of the facility shall be pruned, trimmed, repaired or replaced immediately by the Contractor at no cost to the Department. The Engineer will determine whether the damage shall be corrected by pruning, trimming, repair or replacement. The Contractor shall be responsible for any damage to public or private property which may occur as a result of the spraying operation.

The Contractor shall possess the appropriate license and permit required by the State of Alabama Department of Agriculture and Industries for conducting business in the State of Alabama. All personnel directly involved in the application of the herbicide solution, to include operators and project supervisory personnel, shall be experienced in the ground application of pesticides on highway rights-of-way. Operators and project supervisors involved with this project shall possess a commercial applicator permit issued by the State of Alabama Department of Agriculture and Industries covering the “Right- of-Way” category. The Contractor will furnish two copies of product labels and material safety data sheets for the products used on the project. One copy of each will be furnished to the Engineer and one copy will be kept with the vehicles applying the herbicide at all times. While spraying, care shall be exercised to prevent damage by spray drift or direct contact of herbicide to areas containing plantings of shrubs and bushes, designated wildflower areas, deciduous or evergreen trees, residential plantings, vegetable or flower gardens, any susceptible farm crops, or other desirable plants. In the event of damage to any desirable plants which includes damage or “brown-out” to low hanging limbs of trees along the right-of-way, the Contractor will correct by either replacement, pruning, trimming or compensation of any damages caused by the misapplication or drift of the herbicide solution immediately following visual recognition, verbal or written notification and/or instructions from the Engineer. No herbicide solution shall be sprayed without a drift control agent. No spraying shall be undertaken when the wind velocity is 10mph {16 km/h} or greater. No spraying shall be undertaken during a rain, when rain is imminent, or when foliage is wet. In the event a rain occurs producing a rainfall of one-tenth of an inch {2.5 mm} within four hours or less after the treatment of an area, the area shall be retreated without additional compensations. No spraying shall be undertaken during extended periods of extremely high temperatures and drought conditions. The Contractor shall take extreme care to ensure that herbicide does not enter any lake, stream, pond or wetlands. The speed of any vehicle used to apply the herbicide solution to the highway right-of-way, shall not exceed 11 mph {18 km/h} when operated from the roadway/paved shoulder surface or 5 mph {8 km/h} when operated off the improved portion of the roadway. The pattern of spray shall be such as to provide even, uniform coverage.

The Contractor shall assume all liability for any damage resulting from the application of the herbicides for this project and shall hold the State of Alabama harmless from any claims arising from this damage. It is illegal to place herbicides in a manner that is not consistent with the requirements shown on the herbicide container labeling

It shall be the Contractor’s responsibility to “scout ahead” for each day’s anticipated work. Department-furnished forms (BM-196) “Herbicide Scouting Report” shall be completed prior to the beginning of each day’s work. A completed and signed copy shall be furnished to the Department’s Engineer for each day’s operation. The Contractor shall account for each day’s work and provide information on location, area covered, weather conditions, personnel, equipment, herbicide used, rates and productivity. This information shall be provided on the Department’s “Herbicide Treatment Report”, which will be STORMWATER TURBIDITY CONTROL 577

provided by the Department. A completed and signed copy of this report shall also be furnished to the Department’s Engineer for each day’s work.

669.04Method of Measurement

Item 669-A will be measured in acres {hectares} computed from surface measurements taken parallel to the treated surface. Computations will be to the nearest 0.1 of an acre {0.1 ha}. Item 669-B will be measured by the gallon {liter} of dispensed solution with measurements taken from the storage vessel before and following dispersal to determine the actual amount of solution used. Computations will be to the nearest gallon {L}. Item 669-C will be measured by the square yard {square meter} of dispensed solution with surface measurements taken parallel to the treated surface. Computations will be to the nearest 0.1 square yard {0.1 square meter}.

Basis of Payment

Payment for all satisfactorily completed work of pre-emergent herbicide application as specified, measured as provided above, will be paid for at the contract bid price which shall be full compensation for furnishing all labor, equipment, herbicides, adjuvants, carrier, fuels, incidentals and liability insurance necessary to complete the work. Partial payments will be made on monthly estimates based on the percentage of the total work performed as estimated by the Engineer.

669-A Broadcast Post-Emergent Herbicide Treatment ( * ) ( ** ) ( *** ) ( **** ) per acre {ha} 669-B Spot Post-Emergent Herbicide Treatment ( * ) ( ** ) ( *** ) ( **** ) per gallon {L} 669-C Spot Post-Emergent Herbicide Treatment ( * ) ( ** ) ( *** ) ( **** ) per square yard {square meter} * Specify Type ** Specify Rate *** Specify Carrier Rate of Application **** Specify Type of Carrier STORMWATER TURBIDITY CONTROL

672.01Description

This Section shall cover active and passive treatment methods of reducing the turbidity level of construction stormwater. Turbidity is typically the result of fine soil particles of erodible material exposed during construction, dislodged by precipitation and runoff, and subsequently suspended in stormwater. Conventional means of erosion and sediment control are not designed to remove turbidity from construction stormwater. Additional measures must be implemented to remove the suspended materials from the water. Chemical flocculants are used to increase the particle size of suspended materials making them easier to remove. Prior to discharging construction stormwater, flocculated materials should be removed to the maximum extent practicable. Active treatment should be used as a supplement to passive treatment for stormwater discharges that do not meet water quality standards. Active treatment typically employs mechanical pumping of captured stormwater as the means of introducing flocculant prior to mechanical filtering of flocculated materials. Passive treatment typically employs precipitation and runoff as the means of introducing flocculant prior to physical settling of flocculated materials, typically by means of filtering devices and sedimentation basins.

672.02Materials

The Active Treatment System shall be designed to treat and reduce the turbidity level of construction stormwater discharges to meet state water quality standards and the requirements of the NPDES Construction General Permit at the flowrate required in the plans. The Active Treatment System flowrate specified is designed to dewater the basin within 10 hours. Typical equipment and materials may include pumps, manifolds, flocculants, filter bags, sand media filters and other items designed to STORMWATER TURBIDITY CONTROL 578

remove suspended materials from construction stormwater. The Contractor shall submit to the Engineer the proposed Active Treatment System for review as part of the Contractor’s Stormwater Management Plan that is described in Subarticle 108.04(b).

Flocculant shall be of the type that is manufactured for use in reducing turbidity caused by soil erosion and sediment transport. All forms of Flocculant utilized on a project shall be compatible and shall be provided from a single manufacturer. Flocculant may be in the form of blocks, powder, sock sets or other non-liquid forms. Liquid forms of Flocculant may only be utilized in a monitored active treatment system. The Contractor shall be responsible for the testing of the project soil and potential sediment and for the proper selection of those Flocculants that have a soil specific chemical makeup. Flocculant application rates shall be per the manufacturer’s recommendations. A list of acceptable Flocculants (LIST II-24 “TEMPORARY AND PERMANENT EROSION AND SEDIMENT CONTROL PRODUCTS”) is given in the ALDOT’s MSDSAR manual. For Flocculants without prior acceptance, Contractor shall submit to the Engineer three copies of documentation of the effectiveness of the Flocculant, Material Safety Data Sheets, and the manufacturer's 7-day Chronic Ceriodaphnia Reproduction Testing for review and approval by the State Construction Engineer prior to use on the project.

Turbidimeters shall be devices capable of measuring the nephelometric turbidity units (NTU) of construction stormwater that meets the following requirements:  Portable waterproof device that meets USEPA Method 180.1 with a 0-1000 NTU range;  Sample Tubes, Calibration Kit, and Protective Carrying Case;  Rechargeable Battery, USB Interface, Cable, and Computer Software. A list of equipment acceptable for use in this application (List II-24 “TEMPORARY AND PERMANENT EROSION AND SEDIMENT CONTROL PRODUCTS”) is given in the ALDOT’s MSDSAR manual. Information concerning this list is given in Subarticle 106.01(f).

672.03Construction Requirements

The Contractor shall provide an Active Treatment System at the locations given in the plans or as directed by the Engineer. Treated construction stormwater discharges that do not meet state water quality standards or that do not meet the requirements of the NPDES Construction General Permit (CGP) will not be allowed. Active Treatment Systems will typically be utilized for the dewatering of sedimentation basins. Valves located on the outlet pipe of the basin dewatering device shall remain closed until such time that the potential discharge meets state water quality standards and the requirements of the NPDES CGP. If discharge standards are not met and the sedimentation basin volume reaches 2/3 full or there is forecasted rain, the Engineer will determine if the basin should be dewatered by means of the Active Treatment System. Weather permitting, discharges may be recirculated into sedimentation basins in an effort to achieve discharge standards. The Engineer may also direct dewatering by means of the Active Treatment System to facilitate sedimentation basin maintenance. The Contractor shall ensure proper Flocculant dosing of the Active Treatment System per the manufacturer’s dosing recommendations to prevent the discharge of any harmful levels of Flocculant. The turbidity level of the Active Treatment System discharge and the effectiveness of the Flocculant shall be monitored by the Contractor and will be verified by the Engineer.

The Contractor shall apply Flocculant at the locations given in the plans or as directed by the Engineer. Flocculant shall be introduced to flowing stormwater at locations such as ditch checks, temporary slope drains and forebays of sedimentation basins, prior to retention BMPs intended to promote settling and capture of flocculated material. Heavy sediment and sand should be captured prior to the location of the Flocculant application. Flocculant shall never be applied directly to live streams or waters of the state. Flocculant shall be applied in accordance with the Flocculant manufacturer's dosing recommendations and the requirements shown on the plans for construction stormwater turbidity reduction. The effectiveness of the Flocculant will be monitored by the Engineer. ALDOT and Contractor QCIs shall inspect Flocculant applications after each rain event to determine if the reapplication of Flocculant is needed.