In 1995 as part of the process to assess the suitability of a site near Sellafield, Cumbria, for a deep geological repository for solid intermediate level and some solid low level radioactive waste, United Kingdom Nirex Limited (Nirex) commissioned a series of long duration pumping tests in the various stratigraphic horizons at the site. Two of the pumping tests were conducted in vertically adjacent sections of the lower Sherwood Sandstone Group (SSG) whilst pressures were monitored at discrete intervals in surrounding monitoring boreholes. Responses were observed in over twenty monitoring zones at various levels around the pumped sections during both tests. In order to arrive at an understanding of the hydraulic system in the SSG, a systematic methodology was adopted to analyse the data sets from the pumping tests. Preliminary analysis of the data from each responding zone used the standard 2D radial flow analytical approach. This indicated that, whilst responses conformed broadly to this model, there were important deviations. Three different analytical modifications were adopted to assess the significance of these deviations; a partial penetration model, a bounded aquifer model and a generalized radial flow model. The use of the different models allowed a conceptual model of flow processes occurring in the SSG to be developed.

Hodson, P.V., M. Castsnguay, C.M. Couiilard, C. Desjardins, E. Pel[etier, and R. Mcleod. 1994. Spatial and temporal variations in chemical contamination of American eels, Anguilh rostrata, captured in the estuary of the St. Lawrence River. Can. I. Fish. Aquat. Sci. 51 : 464-478.Levels of polychlorinated biphenyls (PCBs), mirex, and pesticides were 10-100 times higher in migratory adult American eels, Anguilla rostaata, sampled at Karnouraska, Quebec, in 1994) than in eels from an uncsntarr~inated reference tributary; concentrations in eels within the estuary varied little among sites. In contrast, mercury levels were the same at estuarine and reference sites, suggesting natural sources or atmsspheric deposition of mercury. Dioxins, furans, and polynuclear aromatic hyalrocarbons were virtually absent at all sites. During the 7 wk of migration, levels of PCBs, n~irex, and pesticides in eels increased, while mercury did not. Since 1982, levels of PCBs and mirex have declined by 68 and 56%, respectively, and the percentage of eels exceeding human health guidelines for PCBs and mirex was about twofold lower in 1990 than in 4 982. bevels of other pesticides have also declined, except that dieldrin is unchanged since 1982. While chemical concentrations are declining, levels of specific, highly toxic PCB congeners are sufficiently high that eel consumption by beluga whales (Dejphinapterus leucas) is still likely to be hazardous. The hazard to the eels themselves is unknown due to a scarcity of toxicity data, but the highest concentrations of chemicals were observed in gonads.Cher des anguifles d1Am6rique, AwguilBa rostrata, adultes en migration, echantillsnnees a Karnouraska (Quebec) en 1990, les concentrations de biphknyles polychlor4s (BPC), de mirex et de pesticides btaient 10 100 fois plus elevees que chez %es anguilles provenant d'un affluent tkmoin non pollue; dans I'estuaire, les concentrations variaient peu chez les anguilles d'un site 5 I'autre. Par contre, les teneurs en mercure btaient les rnemes dans I'estuaire et aux sites tbmoins, ce qui semble indiquer I'existence de sources naturelles s u de d6p6t d'origine atmospherique du rnercure. Les dioxines, Bes furanes et ies hydrocarbures aromatiques polynucleaires 6taient pratiquernent absents de tous les sites. Pendant les sept semaines de la migration, les concentrations de BPC, de mirex et de pesticides chez Ies anguilles augrnentaient, mais pas ies teneurs en rnercure. Depuis 1982, les concentrations de BPC et de rnirex ont baisse respectivement de 68 j, 56%, et le pourcentage d'anguilles chez lesquelles la teneur en BPC et en mirex dkpassait Ie niveaee autorisk pour la santk humaine 6tait envirsn cjleux fois plus bas en 1990 qea'en 1982. Les concentrations d'autres pesticides ont aussi baissk, sauf celle de dieldrine qui ne bsuge pas depuis 1982.Tandis que les concentrations de produits chirniques dirninuent, les teneurs en certains cong6ni?res de B?C extrernement toxiques restent assez klevbes pour que la consomrnation d'anguilles par le bkluga (Delphinapte...