Padma Multipurpose Bridge Project

Annex 8-1Project Activity/Impact SourceSoil Erosion andsiltationEnvironmental ImpactsSoil erosion and dust from thematerial stockpiles will increasethe sediment and contaminantloading of surface water bodies.Mitigation Measures/ Management GuidelinesThe Contractor shall Stabilize the cleared areas not used for construction activities with vegetation orappropriate surface water treatments as soon as practicable following earthwork tominimize erosion Ensure that roads used by construction vehicles are swept regularly to remove sediment. Water the material stockpiles, access roads and bare soils on an as required basis tominimize dust. Increase the watering frequency during periods of high risk (e.g. highwinds)Constructionactivities in waterbodiesDrinking waterConstruction works in the waterbodies will increase sediment andcontaminant loading, and effecthabitat of fish and other aquaticbiology.Groundwater at shallow depths iscontaminated with arsenic andhence not suitable for drinkingpurposes.The Contractor Shall Dewater sites by pumping water to a sediment basin prior to release off site – do not pumpdirectly off site Monitor the water quality in the runoff from the site or areas affected by dredge plumes,and improve work practices as necessary Protect water bodies from sediment loads by silt screen or bubble curtains or other barriers Minimize the generation of sediment, oil and grease, excess nutrients, organic matter,litter, debris and any form of waste (particularly petroleum and chemical wastes). Thesesubstances must not enter waterways, storm water systems or underground water tables. Use environment friendly and non toxic slurry during construction of piles to discharge intothe river. Reduce infiltration of contaminated drainage through storm water management design Do not discharge cement and water curing used for cement concrete directly into watercourses and drainage inlets.The Contractor Shall Pumping of groundwater should be from deep aquifers of more than 300 m to supplyarsenic free water. Safe and sustainable discharges are to be ascertained prior toselection of pumps. Tube wells will be installed with due regard for the surface environment, protection ofgroundwater from surface contaminants, and protection of aquifer cross contamination All tube wells, test holes, monitoring wells that are no longer in use or needed shall bePadma Multipurpose Bridge Design ProjectFinal Report (Environmental Action Plan)Environmental Impact Assessment Report A8-5June 7, 2010