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[en] The latest version of the University of Toronto Glacial Systems Model (UofTGSM) was employed in the development of data sets describing the evolution of surface boundary conditions above a potential spent fuel repository over the course of a 122.5 kyr cycle of glaciation. The new data sets build increased confidence upon the previous UofTGSM generated data sets that Peltier (2006) supplied for this purpose. The components of the UofTGSM have been updated to a framework reflecting the current state-of-the-art, and a new strategy has been adopted to preserve consistency with observations independently of detailed assumptions about ice-sheet dynamics. A mass-balance adjustment is employed to nudge the ice-thickness solution towards the observationally well-validated ICE-6GC reconstruction, and dynamical variability can be analyzed in the context of ensembles with different exponential relaxation time-scales. This approach is used to diagnose ice thickness, permafrost thickness, basal temperature, meltwater production, lake depth, and other two dimensional, time-varying fields from a reference solution along with corresponding local error estimates. Beyond reflecting significant numerical advances that enabled the new UofTGSM to better represent basal processes, ice-shelves, temperate ice-water mixtures and other physics, the new results benefit from the many new measurements that constrained ICE-6GC (and therefore, indirectly, the nudged paleoclimate simulations). Nudging offers a more practical approach to leading-order data assimilation and error estimation than Bayesian calibration, which was employed in Peltier (2006), and which will continue to be of use in more detailed explorations of observationally constrained model parameter spaces. Rather than consisting of discrete time-series at the sites of hypothetical spent-fuel repositories, the new dataset also includes time-varying two-dimensional geographic distributions covering all of Canada. (author)
[en] This Quality Assurance Plan (QAP) provides the overall Quality Assurance (QA) program requirements, technical planning, and general quality practices to be applied to the U.S. Department of Energy (DOE) Environmental Management (EM) Nevada Program Soils Activity. The QAP requirements are consistent with the Quality Systems for Environmental Data and Technology Programs–Requirements with Guidance for Use (ANSI/ASQ, 2004); the Intergovernmental Data Quality Task Force Uniform Federal Policy for Quality Assurance Project Plans (IDQTF, 2005); and 10 Code of Federal Regulations (CFR) 830.120, Quality Assurance (CFR, 2017a), which apply to specific activities performed under the Soils Activity. The EM Nevada Program owns and is responsible for maintaining this QAP. Individual participants are responsible for implementing the requirements of this QAP in accordance with their own approved programs, processes, plans, and procedures. If a participant’s requirement document differs from this QAP, the stricter requirement will take precedence.
[en] Measurements of the dynamic response of a rock mass are inevitable in the systematic long-term monitoring and the maintenance of the radioactive waste disposal repository. With this point of view, AE (acoustic emission) detection is considered to be a promising technique for monitoring the in-situ performance of a rock mass. In this study, the propagation and interactions of guided acoustic waves in a waveguide connector, which is required in an in-situ application of an AE monitoring system were investigated and the coupling methods of a waveguide to the surface of rock mass were compared. The changes in acoustic wave amplitude, time delay, frequency variation, and system transfer function were measured between the waveguide and a rock sample. Subsequently the waveguide coupling conditions filled with epoxy were compared with a mechanical type of coupling for the validity of field application. The results derived from this study can be valuable information for the quantitative analysis of signal processing in AE source localization and the degree of crack damage in a radioactive waste repository. (author)
[en] This Working Report presents the main results of Posiva Oy's environmental monitoring programme on Olkiluoto Island in 2011. These summary reports have been published since 2005. The environmental monitoring system supervised by Posiva Oy produces input for biosphere modelling for long-term safety purposes as well as for monitoring the state of the environment during the construction (and later operation) of ONKALO underground rock characterization facility. Part of the monitoring is performed by the company running the nuclear power plants on the island, Teollisuuden Voima Oy (TVO). Monitoring has been carried out for varying periods of time depending on the sector: some monitoring activities performed by TVO originate from the 1970s and the repository-related environmental monitoring of Olkiluoto from the early 2000s. The monitoring programme evolves according to experiences gained from the modelling work and increased understanding of the site. Monitoring activities in 2011 proceeded according to the plans. The land-use of the island continues to change due to the construction work of OL3, ONKALO and related infrastructure, but the remaining natural environment resembles other coastal locations. The amount of nitrogen in the bulk deposition increased in 2011, whereas that of sulphur decreased. Some litterfall fractions showed higher Al and Fe values than earlier, likely caused by soil dust. Proximity of the sea is seen in wet deposition and soil solution results. Soil solution also reflects the young age of soils. Undestorey vegetation has shown no essential changes during the monitoring period. Mammalian fauna on the island is typical of coastal areas in Southwestern Finland. Game catches vary according to hunting pressure and natural variation in populations. The condition of the nearby sea is affected by the continuous land uplift, the shallowness of the area, the weather conditions, the general condition of the Bothnian Sea, the nutrient and sediment loads carried by rivers Eurajoki and Lapinjoki, and the cooling water from the nuclear power plant. In 2011 both the winter and open water season concentrations of substance matter were low in the sea. Winter was colder than on average, and the discharges, runoffs and consequently the nutrient concentrations were lower than normally. Summertime nutrient contents were on an ordinary level. The summer was warm and rainy, which increased the growth of algae. The water quality of the majority of the monitored private drilled wells is poor due to their natural properties. Their water level is not affected by the construction of ONKALO. In the monitoring of the outlet waters of ONKALO the pH limit set in the environmental programme (9.5) was exceeded once in 2011. This led to no actions, since the pH level returned to a lower level after this instance. High suspended solids concentration was measured in the summer from the ditch running by the rock piling area; however, there were also some plant parts in the sample. The construction works and road traffic have a raising effect on the noise levels of the immediate surroundings. (orig.)
[en] As a part of the site investigations for the disposal of spent nuclear fuel, hydraulic conductivity measurements were carried out with HTU-equipment in drillholes OL-KR19, OL-KR45 and OL-KR46 at Eurajoki, Olkiluoto. The objective was to investigate the distribution of the hydraulic conductivity in the surrounding bedrock volume. Measurements were carried out during 2009 and 2010. The total length of the borehole OL-KR19 is 544,34 m, 241,80 m of which was covered by 121 standard tests with 2 m packer separation as specified in the measurement plan. Respectively, OL-KR45 is 1023,30 m long and 63 similar tests were made in it covering 126,00 m of the hole and OL-KR46 600,10 m long, 151 tests made covering 301,35 m. The measured sections are around the depths of the planned repository. Double-packer constant-head method was used throughout with nominal 200 kPa overpressure. Injection stage lasted normally 20 minutes and fall-off stage 10 minutes. The tests were often shortened if there were clear indications that the hydraulic conductivity is below the measuring range of the system. The pressure in the test section was let to stabilise at least 5 min before injection. In some test sections the test stage times were extended. Two transient (Horner and 1/Q) interpretations and one stationary- state (Moye) interpretation were made in-situ immediately after the test. The Hydraulic Testing Unit (HTU-system) is owned by Posiva Oy and it was operated by Geopros Oy. (orig.)
[en] As a part of the site investigations for the disposal of spent nuclear fuel, hydraulic conductivity measurements were carried out with the HTU-equipment in drillholes OL KR52 and OL KR47 on the Olkiluoto investigation site. The objective was to investigate the distribution of the hydraulic conductivity in the surrounding bedrock volume. In OL-KR52 measurements were carried out between February 2013 and April 2013 and in OL-KR47 between October 2013 and February 2014. The total length of the drillhole OL-KR52 is 427.35 m, 376.00 m of which was covered by 188 standard tests with 2 m packer separation as specified in the measurement plan. Respectively, OL-KR47 is 1008.76 m long and 312 similar tests were conducted in it covering 624.00 m of the drillhole. These numbers include one equipment test measurement near the surface in OL-KR47. Double-packer constant-head method was used throughout with nominal 200 kPa overpressure. Injection stage lasted normally 20 minutes and fall-off stage 10 minutes. The tests were often shortened if there were clear indications that the hydraulic conductivity is below the measuring range of the system. The pressure in the test section was let to stabilise at least 5 min before injection. In some test sections the test stage times were extended if longer times were needed to obtain correct results or when suited to the working schedule. Two transient (Horner and 1/Q) interpretations and one stationary-state (Moye) interpretation were made in-situ immediately after the test. The Hydraulic Testing Unit (HTU-system) is owned by Posiva Oy and it was operated by Poeyry Finland Oy in co-operation with Geopros Oy. (orig.)
[en] Biosolids are extensively used in agriculture as fertilizers while offering a practical solution for waste disposal. Many pharmaceutical and personal care products (PPCPs), such as triclosan and triclocarban, are enriched in biosolids. Biosolid amendment changes soil physicochemical properties, which may in turn alter the persistence of PPCPs and hence the risk for secondary contamination such as plant uptake. To delineate the effect of biosolids on PPCPs persistence, triclosan and triclocarban were used as model compounds in this study and their sorption (K_d) and persistence (t_1_/_2) were determined in different soils before and after biosolid amendment. Biosolids consistently increased sorption of triclosan and triclocarban in soil. The K_d of triclosan increased by 3.9–21 times following amendment of a sandy loam soil with biosolids at 2–10%. The persistence of both compounds was prolonged, with t_1_/_2 of triclosan increasing from 10 d in the unamended soil to 63 d after biosolid amendment at 10%. The relationship between t_1_/_2 and K_d was further examined through a meta-analysis using data from this study and all relevant published studies. A significant linear relationship between t_1_/_2 and K_d was observed for triclosan (r"2 = 0.69, p < 0.01) and triclocarban (r"2 = 0.38, p < 0.05) in biosolid-amended soils. On the average, when biosolid amendment increased by 1%, t_1_/_2 of triclosan was prolonged by 7.5 d, while t_1_/_2 of triclocarban was extended by 4.7 d. Therefore, biosolid amendment greatly enhances persistence of triclosan and triclocarban, likely due to enhanced sorption or decreased chemical bioavailability. This finding highlights the importance to consider the effect of biosolids when evaluating the environmental risks of these and other biosolid-borne PPCPs. - Highlights: • K_d and t_1_/_2 of triclosan and triclocarban were determined in soil with or without biosolid amendment. • Correlation of K_d and t_1_/_2 was tested using values from this study and all available literature. • Negative relationships were observed between K_d and t_1_/_2 for both compounds. • Biosolid amendment significantly prolonged persistence of triclosan in soil. - Amendment of biosolids significantly inhibited degradation and increased persistence of triclosan and triclocarban, likely due to decreased bioavailability.