title: Anatomy of a decision: potential regulatory outcomes from changes to chemistry protocols in the Canadian Disposal at Sea Program.
abstract: Environment Canada currently assesses dredged material proposed for disposal at sea using a two-tiered assessment framework. Tier 1 determines sediment geophysical properties and concentrations of four regulated chemical constituents (Cd, Hg, PAH and PCB), and "other chemicals of interest" based on lower action levels; this is followed by biological assessment. EC is pursuing a "data mining" approach to evaluate potential refinements by compiling sediment chemistry and toxicity datasets, and subjecting them to a series of decision protocols. This paper reports on database development and initial use, and recommends potential changes to Tier 1 chemical protocols and further work to address other aspects of the framework. Major findings include the poor performance of Hg and Cd as sentinels for other metals, the significance of the list of analytes (vs. the specific SQGs used) in decisions, and the potential for chemical upper action levels to save the expense of unnecessary toxicity testing.
authors: SEA Environmental Decisions, Ltd., 1 South Cottages, The Ford, Little Hadham, Hertfordshire SG11 2AT, United Kingdom. drsea@cvrl.org
authors: Sabine E
authors: SE
authors: Apitz
authors: Suzanne
authors: S
authors: Agius
mesh_terms: D002170:Canada; D057225:Data Mining; D004784:Environmental Monitoring / Q000379:methods*; D058735:Environmental Policy; D019015:Geologic Sediments / Q000737:chemistry; D011078:Polychlorinated Biphenyls / Q000032:analysis; D011084:Polycyclic Aromatic Hydrocarbons / Q000032:analysis; D012037:Refuse Disposal / Q000331:legislation & jurisprudence / Q000379:methods*; D012623:Seawater / Q000737:chemistry; D014874:Water Pollutants, Chemical / Q000032:analysis*; D014877:Water Pollution, Chemical / Q000331:legislation & jurisprudence / Q000706:statistics & numerical data
chemical_list: D011084:Polycyclic Aromatic Hydrocarbons; D014874:Water Pollutants, Chemical; D011078:Polychlorinated Biphenyls