Terms of Reference - North Queensland Bulk Ports Corporation

managed, should be derived from the Acid Sulfate Soils Laboratory MethodsGuidelines (Ahern et al. 2004) and the Soil Management Guidelines (Dear et al. 2002).Assessment of marine sediments should be undertaken in accordance with the NAGD.Detail specific measures to maintain sediment quality to nominated quantitativestandards within the project and surrounding areas, particularly where futuremaintenance dredging may be required.Note: Dredging with disposal of spoil on land (above the MHWST) requires anallocation of quarry material, under the provisions of the Coastal Act, prior toapplication for tidal works approval under SPA.Potential impacts and mitigation measuresDescribe the potential environmental impacts caused by the project on coastal waterand sediment quality, and associated management and mitigation measures, including:• potential impacts associated with constructing and operating the coastal and marinefacilities• in the context of the DMP, potential impacts due to dredging and dredge materialdisposal, including disturbance of fine-grained sediments (for examples, metals,nutrients, PASS or contaminant release), reduced light attenuation and additionalsedimentation on coral reefs and seagrasses• potential accidental discharges of contaminants during construction and operation ofthe coastal and marine facilities• release of contaminants from marine structures and vessels, including potential forintroducing marine pests• stormwater run-off from the coastal facilities and associated infrastructure• flooding of local watercourses and other extreme weather events.Provide management strategies for dredging, loading and spoil disposal, including anyrequired trigger levels for management actions linked to quantitative measurements ofwater quality.For any onshore dredge spoil disposal options, provide a detailed assessment, withappropriate staging plans. The assessment should demonstrate the quality of the waterdischarged from dredge spoil disposal areas will meet standards necessary to achievewater quality objectives and therefore maintain receiving water environmental valuesthroughout the period of dredge spoil disposal on land. Consideration should be givento:• quantities of tailwater likely to be generated from dredging activities• the settling rate of fine sediments from all dredge material types• the residence time within settling ponds prior to discharge (related to dredgepumping rate, ratio of solids to water in spoil, settling rates, available capacity of thedisposal and settling areas, potential bulking factor, intensity and duration of rainfallevents with consideration given to the worst case scenario for these factors)• source of material for bunds and bund wall stability• measures to limit channelling and sediment re-suspension in settling ponds- 34 - Contents of the EISDudgeon Point Coal Terminals ProjectTerms of reference for an environmental impact statement