Presentation on theme: "CASE STUDY. PORT SUSTAINABILITY: DREDGED MATERIAL MANAGEMENT Contact: T.ANGEL DEL VALLS University of Cádiz UNESCO/UNITWIN7WiCop. Marine and Environmental."— Presentation transcript:
CASE STUDY. PORT SUSTAINABILITY: DREDGED MATERIAL MANAGEMENT Contact: T.ANGEL DEL VALLS University of Cádiz UNESCO/UNITWIN7WiCop. Marine and Environmental Sciences Faculty Av. República Saharaui, s/n Puerto Real (Cádiz) SPAIN Phone: Fax:
Outline I General description of the areas Port of Cadiz; Huelva, Santos Problem description Solutions / measures Effects and lessons learnt
Description of the areas Cadiz bay
Description of the areas Cadiz bay Economy has been principally based on maritime commerce, fishing and ship construction as it hosts an important shipyard. It is entry and exit door for merchant traffic from the European Union to the Magreb countries and also connects the Iberian penynsula with Canary Islands.
Description of the areas Huelva
Description of the areas Huelva Important mining and metallurgical activities dating back three thousand years and based on pyrite (FeS2) and other sulphuric minerals. Important industrial and fishing port with several dockyards and quays.
Description of the areas Santos
Description of the areas Santos Biggest Brazilian industrial complex while major Latin American port. Environmental importance: São Vicente Estuarine System surrounded by mangroves (43% of total mangrove area of São Paulo).
Dredging is an essential activity for maritime navigation: Deepening navigable waterways Maintenance dredging sand and mud deposited by water currents estuarine areas –high deposition of riverine sediments. Problem description
International framework of recommendations for dredged material characterisation and management. London Convention OSPAR etc. Pose the sediments any risk to the environment?
Solutions and measures Step 1: Project planning, including the nature and the scope of the activities, the potential dredged material placement options and the regulatory requirements. Step 2: Initial evaluation, where available data is examined. It may lead to the conclusion that no further pre-dredging evaluations are needed. If needed, one proceeds to Step 3. Step 3: Physical, chemical and biological characterizations of dredged material. Step 3: Physical, chemical and biological characterizations of dredged material. Step 4: Interpretation of results of the data assembled and evaluated.
Solutions and measures Traditional physico-chemical characterisation Grain size/TOM Metallic compounds –As, Cd, Cr, Cu, Hg, Ni, Pb, Zn Organic compounds –Σ 7 PCBs Not always required- Σ 12 PAHs Comparison with limit values in use- National Action Levels, i.e. Spain Other empirically derived SQGs, i.e. TEL/PEL; ERL/ERM; etc.
Solutions and measures Action Level Approach AL1AL2 8XAL2 No riskEvident risk ?
Solutions and measures Management requirements in Spain according to dredged material characterisation
Solutions and measures Ecotoxicological characterisation of sediment samples from Huelva, Cadiz and Santos BioassayExposure route DurationType of testsEndpoints Adult amphipodWhole sediment 10 daysAcuteMortality Informs on the potential toxic effects of sediments on benthic infauna.
Solutions and measures Ecotoxicological characterisation of sediment samples from Huelva and Cadiz BioassayExposure routeDurationType of testsEndpoints Sea urchin embryos Elutriates48 hoursAcute/chronicArrested or abnormal development Normal Abnormal Informs on the potential toxic effects of aqueous extracts on pelagic organisms during dredging/disposal.
Solutions and measures Bioaccumulation potential of metals in commercial clams -Huelva and Cadiz- BioassayExposure routeDurationEndpoint Juvenile clams Whole sediment 28 daysTissue concentrations of key compounds Informs on the potential bioaccumulation of compounds in commercial organisms/possible human health risks.
Solutions and measures Dredged sediments from Port of Cadiz SampleCategoryToxicity?CommentsManagement option CA1INoSandBeach nourishment CA2III-Whole sediment -Elutriates MudConfined disposal, isolation depending on Toxicity Identification Evaluations CA3 II -Elutriates -Bioaccumulation potential of Hg MudFurther assessment on environmental windows CA4
Solutions and measures Dredged sediments from Port of Huelva SampleCategoryToxicity?CommentsManagement option H1I-Whole sedimentMudConfined disposal, soft isolation H2III-Whole sediment -Elutriates MudConfined disposal, hard isolation H3III-Whole sedimentMud/sandSeparation (sand/mud) Confined disposal, hard isolation H4INoCoarseLand reclamation Construction
Solutions and measures Dredged sediments from Port of Santos SampleCategoryToxicity?CommentsManagement option SSV1INoFines <10%Beneficial uses SSV2IIYesFines <10%Not suitable for sea disposal SSV3IIYesFines <10%Not suitable for sea disposal SSV4IYesFines <10%Not suitable for sea disposal SSV5IYesFines <10%Not suitable for sea disposal SSV6IYesFines <10%Not suitable for sea disposal Further information on potential toxicity would allow to identify least detrimental management option.
Environmental benefits: Risk-based decisions. Environmental benefits: Risk-based decisions. Integrated approach for dredged material management (CHEMICAL+ECOTOXICOLOGICAL): Economic benefits: Re-use of contaminated but not toxic sediments Economic benefits: Re-use of contaminated but not toxic sediments Costs of characterisation: Only for not-completely characterised sediments - categoría II-. Management costs: For intermediate contaminated sediments causing toxicity. - +