The Inpluence of Borehole Flushing on the Concentration of Microbes in Granitic Groundwaters.

1993 ◽  
Vol 333 ◽  
Author(s):  
S. Stroes-Gascoyne ◽  
M. Gascoyne ◽  
C.J. Hamon ◽  
D. Jain ◽  
P. Vilks
Keyword(s):  
Fracture Zone ◽  
Research Laboratory ◽  
Microbial Growth ◽  
Management Program ◽  
Flow Rates ◽  
Particle Count ◽  
Tenfold Increase ◽  
Total Particle ◽  
Underground Research Laboratory ◽  
Nuclear Fuel Waste

ABSTRACTA number of groundvater parameters have been studied at AECL’s Underground Research Laboratory (URL) in support of the Canadian Nuclear Fuel Waste Management Program. The concentration of microbes in groundvater is of interest as they may modify the transport of dissolved radionuclides. Preliminary results from an earlier study suggested that the microbe concentrations may be affected by the extent of borehole flushing prior to sampling. A study was therefore carried out in which packer-isolated intervals of two boreholes intersecting a fracture zone at 250-m depth in the URL were flushed and sampled on two occasions at various flow rates. High initial microbial concentrations (most likely due to leaching of nutrients from sample tubes) decreased rapidly as flushing progressed, suggesting enhanced microbial growth near the top of the borehole zone. Also, a tenfold increase in flow rate during flushing caused an increase in microbial concentrations in the groundwater of one of the boreholes, concurrent with an increase in total particle count. This suggests that particulate and biofilm material may be flushed out of the fracture zone at this particular location.

Site Decommissioning of AECL Whiteshell Laboratories

2004 ◽  
Vol 824 ◽  
Author(s):  
Grant W. Koroll
Keyword(s):  
Waste Management ◽  
Environmental Assessment ◽  
Materials Science ◽  
Nuclear Research ◽  
Management Program ◽  
Nuclear Facilities ◽  
Safety Research ◽  
Nuclear Installation ◽  
Underground Research Laboratory ◽  
Nuclear Fuel Waste

AbstractAECL Whiteshell Laboratories (WL), near Winnipeg, Canada has been in operation since the early 1960s. R&D programs carried out at WL include a 60 MW organic-cooled research reactor, which operated from 1965 to 1985, reactor safety research, small reactor development, materials science, post irradiation examinations, chemistry, biophysics and radiation applications. The Canadian Nuclear Fuel Waste Management Program was conducted and continues to operate at WL and also at the nearby Underground Research Laboratory.In the late-1990s, AECL began to consolidate research and development activities at its Chalk River Laboratories (CRL) and began preparations for decommissioning WL. Preparations for decommissioning included a staged shutdown of operations, planning documentation and licensing for decommissioning. As a prerequisite to AECL's application for a decommissioning licence, an environmental assessment (EA) was carried out according to Canadian environmental assessment legislation. The EA concluded in 2002 April when the Federal Environment Minister published his decision that WL decommissioning was not likely to cause significant adverse environmental effects and that no further assessment by a review panel or mediation would be requiredIn 2002 December, the Canadian Nuclear Safety Commission issued a decommissioning licence for WL, valid until December 31, 2008. The licence authorized the first planned phase of site decommissioning as well as the continuation of selected research programs. The six-year licence for Whiteshell Laboratories was the first overall decommissioning license issued for a Canadian Nuclear Research and Test Establishment and was the longest licence term ever granted for a nuclear installation of this complexity in Canada.The first phase of decommissioning is now underway and focuses on decontamination and modifications to nuclear facilities, such as the shielded facilities, the main R&D laboratories and the associated service systems, to achieve a safe state of storage-with-surveillance. Later phases have planned waste management improvements for selected wastes already in storage, eventually followed by final decommissioning of facilities and infrastructure and removal of most wastes from the site.This paper provides an overview of the planning, environmental assessment, licensing, and organizational processes for decommissioning and selected descriptions of decommissioning activities currently underway at AECL Whiteshell Laboratories.

Decommissioning AECL Whiteshell Laboratories

2003 ◽  
Author(s):  
G. W. Koroll ◽  
M. A. Ryz ◽  
J. W. Harding ◽  
W. R. Ridgway ◽  
M. J. Rhodes ◽  
...  
Keyword(s):  
Waste Management ◽  
Environmental Assessment ◽  
Materials Science ◽  
Nuclear Research ◽  
Management Program ◽  
Nuclear Facilities ◽  
Safety Research ◽  
Nuclear Installation ◽  
Underground Research Laboratory ◽  
Nuclear Fuel Waste

AECL operates two nuclear R&D laboratories in Canada, Chalk River Laboratories (CRL) near Ottawa, Ontario, and Whiteshell Laboratories (WL), near Winnipeg, Manitoba. Whiteshell Laboratories have been in operation since about 1965. R&D programs carried out at WL included the WR-1 research reactor, which operated from 1965 to 1985, reactor safety research, small reactor development, materials science, post irradiation examination, chemistry, biophysics and radiation applications. The Canadian Nuclear Fuel Waste Management Program was conducted and continues to operate at WL and also at the nearby Underground Research Laboratory. In the late-1990s, AECL began to consolidate research and development activities at CRL and initiated preparations for decommissioning WL. Preparations for decommissioning included a formal environmental assessment under Canadian environmental assessment legislation, a prerequisite to AECL’s application for a decommissioning licence. In 2002 December, the Canadian Nuclear Safety Commission issued a decommissioning licence for WL, valid until December 31, 2008. The licence authorizes the first planned phase of site decommissioning as well as the continuation of selected research programs. The six-year licence for Whiteshell Laboratories is the first overall decommissioning license issued for a Canadian Nuclear Research and Test Establishment and is the longest licence term ever granted for a nuclear installation of this complexity in Canada. The first phase of decommissioning is now underway and focuses on decontamination and modifications to nuclear facilities, such as the shielded facilities, the main R&D laboratories and the associated service systems, to achieve a safe state of storage-with-surveillance. Later phases have planned waste management improvements for selected wastes already in storage, eventually followed by final decommissioning of facilities and infrastructure and removal of most wastes from the site. This paper provides an overview of the planning, environmental assessment, licensing, and organizational processes for decommissioning and selected descriptions of decommissioning activities currently underway at AECL Whiteshell Laboratories.

Representation of Fracture Zone Interpretation Uncertainty in 3D Geological Models of the Mizunami Underground Research Laboratory, Japan

2003 ◽  
Vol 807 ◽  
Author(s):  
Matthew J. White ◽  
Hiromitsu Saegus
Keyword(s):  
Fracture Zone ◽  
Research Laboratory ◽  
3D Structure ◽  
Geological Structure ◽  
Granitic Rocks ◽  
Geological Environment ◽  
Fracture Zones ◽  
Geological Models ◽  
Hydrogeological Properties ◽  
Underground Research Laboratory

ABSTRACTThe Japan Nuclear Cycle Development Institute (JNC) is undertaking research into the deep geological environment in Japan in the Tono area of Japan. In the Mizunami Underground Research Laboratory (MIU) Project, located in the Tono area, JNC is carrying out surface-based investigations and will excavate an Underground Research Laboratory (URL) in order to establish comprehensive techniques for investigating and characterising the geological environment. The MIU Project focuses on the investigation of the granitic rocks of the Toki Granite. The geological structure and hydrogeological properties of the Toki Granite are closely affected by the regional fracture zones and faults. The interpretation of these features is undertaken in 3D and directly linked into 3D hydrogeological models. Significant uncertainty exists in the 3D interpretation of the fracture zones, and geologists must make several assumptions regarding the 3D structure in order to develop the 3D interpretation. In order that these assumptions are communicated to the hydrogeologists, a methodology has been developed for representing uncertainty in the 3D geological models. An important part of the uncertainty representation, is the development of a fracture zone classification in which the uncertainty in both the presence and the geometry of the fracture zone is assigned. Other elements include the development of alternative models, visualisation of raw data, development of conceptual models, development of bounding models, and suitable quality assurance and archiving of modelling projects.

Low Alkaline Cement Used in the Construction of a Gallery in the Horonobe Underground Research Laboratory

2010 ◽  
Author(s):  
Masashi Nakayama ◽  
Haruo Sato ◽  
Yutaka Sugita ◽  
Seiji Ito ◽  
Masashi Minamide ◽  
...  
Keyword(s):  
Fly Ash ◽  
Research Laboratory ◽  
Concrete Lining ◽  
Energy Agency ◽  
Tunnel Support ◽  
Long Term Stability ◽  
Alkaline Conditions ◽  
High Level ◽  
Underground Research Laboratory

In Japan, any high level radioactive waste (HLW) repository is to be constructed at over 300 m depth below surface. Tunnel support is used for safety during the construction and operation, and shotcrete and concrete lining are used as the tunnel support. Concrete is a composite material comprised of aggregate, cement and various admixtures. Low alkaline cement has been developed for the long term stability of the barrier systems whose performance could be negatively affected by highly alkaline conditions arising due to cement used in a repository. Japan Atomic Energy Agency (JAEA) has developed a low alkaline cement, named as HFSC (Highly Fly-ash Contained Silicafume Cement), containing over 60 wt% of silica-fume (SF) and fly-ash (FA). HFSC was used experimentally as the shotcrete material in construction of part of the 140m deep gallery in the Horonobe Underground Research Laboratory (URL). The objective of this experiment was to assess the performance of HFSC shotcrete in terms of mechanics, workability, durability, and so on. HFSC used in this experiment is composed of 40 wt% OPC (Ordinary Portland Cement), 20 wt% SF, and 40 wt% FA. This composition was determined based on mechanical testing of various mixes of the above components. Because of the low OPC content, the strength of HFSC tends to be lower than that of OPC. The total length of tunnel using HFSC shotcrete is about 73 m and about 500 m3 of HFSC was used. The workability of HFSC shotcrete was confirmed in this experimental construction.

Tectonic implications of seismic activity recorded by the northern Ontario seismograph network

1989 ◽  
Vol 26 (2) ◽  
pp. 376-386 ◽  
Author(s):  
R. J. Wetmiller ◽  
M. G. Cajka
Keyword(s):  
Horizontal Stress ◽  
Seismic Profile ◽  
Management Program ◽  
Earthquake Activity ◽  
Seismic Velocities ◽  
Northern Ontario ◽  
Focal Mechanism Solutions ◽  
National Networks ◽  
Nuclear Fuel Waste ◽  
Seismograph Network

The northern Ontario seismograph network, which has operated under the Canadian Nuclear Fuel Waste Management Program since 1982, has provided valuable data to supplement those recorded by the Canadian national networks on earthquake activity, rockburst activity, the distribution of regional seismic velocities, and the contemporary stress field in northern Ontario. The combined networks recorded the largest earthquake known in northwestern Ontario, M 3.9 near Sioux Lookout on February 11, 1984, and many smaller earthquakes in northeastern Ontario. Focal mechanism solutions of these and older events showed high horizontal stress and thrust faulting to be the dominant features of the contemporary tectonics of northern Ontario. The zone of more intense earthquake activity in western Quebec appeared to extend northwestward into the Kapuskasing area of northeastern Ontario, where an area of persistent microearthquake activity had been identified by a seismograph station near Kapuskasing.Controlled explosions of the 1984 Kapuskasing Uplift seismic profile experiment recorded on the northern Ontario seismograph network showed the presence of anomalously high LG velocities in northeastern Ontario (3.65 km/s) that when properly taken into account reduced the mislocation errors of well-recorded seismic events by 50% on average.

Sign in / Sign up

Export Citation Format

Share Document