Soil Reference Material Data Sheets : BGS110 to BGS119

The British Geological Survey (BGS) has produced a suite of 10 new soil Reference Materials, BGS110 to BGS119. They are intended for use as quality control samples for the determination of total elemental concentrations in soils. The Reference Materials contain a wide range of concentrations to cater for different analytical needs, interests and industries, e.g. agriculture, geochemical exploration, contaminated land. Data sheets for each of these materials are available on the BGS website https://www.bgs.ac.uk/sciencefacilities/laboratories/geochemistry/igf/Services/referenceMaterials.html

Validation report for the determination of non-purgeable organic carbon by TOC-V analyser

This report describes the validation of Technical Procedure AGN 2.3.8, Determination of Non- Purgeable Organic Carbon (NPOC), in preparation for accreditation of the analytical method by the United Kingdom Accreditation Service (UKAS)

Validation for the transition of SPSS QI Analyst to the SPC for Excel program for quality control charting

The statistical process control charting software utilised by the Inorganic Geochemistry team, SPSS QI Analyst version 3.5, (1998, (QIA)), was no longer viable because it was incompatible with operating system requirements for networked computers. Therefore, an alternative program, SPC for Excel version 5, (2017, (SPC)), has been validated to replace the legacy version of QIA. The benefits of using SPC include but are not limited to the following: Conformity with accredited QC processes according to the Inorganic Geochemistry Analytical Quality Control Operating Procedure (AGN 1.7) Ease of transferring results from the analytical software Program is accessible to computers connected to the network Control charting and recording QC checks are all accomplished using Excel alone User friendly with moderate Excel skills Lower cost per licence than the latest version of the existing software The following document provides evidence to satisfy the requirements of UKAS accredited Standard ISO17025 by validating the new software system against the existing QIA software according to a validation plan using two complementary approaches. Specifically, this validation document comprises: Tests with a synthetic dataset, which confirms that QIA and SPC for Excel produce the same result against the criteria specified by Analytical Quality Control procedures (AGN 1.7) Tests with standards run during a recent large stream water analysis programme, which confirms that QIA and SPC for Excel control charts are able to perform the same quality control checks for analytes in “real” control sample data A comparative table of terminology differences between QIA and SPC for Excel A companion document “SPC for Excel Instruction manual v2_WORKING VERSION”, provides working guidance on the operation of SPC for Excel version 5 2017, located in Appendix 5

Natural and anthropogenic influences on atmospheric Pb-210 deposition and activity in sediments : a review

The determination of the age of a sediment layer is invaluable for understanding geochemical processes and their time-scales. The application of Pb-210 as a radiometric chronometer has been extensively researched in recent years, being applied to a variety of freshwater, estuarine and marine environments worldwide. The estimation of sedimentation rate changes using Pb-210 dating can also provide valuable information on possible causes for variation in a water body’s physiochemical and biological characteristics; making the technique relevant to environmental remediation. However, to reliably draw conclusions based on Pb-210 dating; a comprehensive understanding of the influence that other natural and anthropogenic variables have on Pb-210 is essential. This literature review summarises the key factors which may influence both unsupported Pb-210 deposition from the atmosphere and the unsupported Pb-210 activity found in sediments. The deposition of unsupported Pb-210 is shown to be predominantly via the rain-out mechanism (within-cloud scavenging) as opposed to wash-out (below cloud), and the suppression or release of Rn-222 exhalation from sediments may also be controlled by surface air temperatures and pressures, which consequently will result in seasonal variations in atmospheric Pb-210 concentrations and Pb-210 deposition. Organic matter (OM), silt and clay content also have an influence on the sediment unsupported Pb-210 activity; thus leading to a general consensus of positive correlation between unsupported Pb-210 activity and the OM, silt or clay content as a result of greater adsorption affinity for Pb-210 and an enhanced specific surface area relative to sand and larger particles. Bioturbation will also impact the unsupported Pb-210 activity in sediments, however mathematical models used to estimate this influence still require further refinement to accurately represent activity variation associated with different species’ burrowing techniques and different soil porosities. Anthropogenic influences on sediment unsupported Pb-210 activity may also have been observed i.e. additional Pb-210 from the anthropogenic source, though research on these are limited and further research is advised in assessing the impact of anthropogenic activities such as farming, mining and fossil fuel combustion

Soil Reference Material Data Sheets : BGS120 to BGS126

There is a paucity of appropriately characterised Reference Materials to inform quality assessments for agronomic chemical analysis of soil. These analyses are used to provide data for systematic regional geochemical/agricultural soil surveys and underpin on-farm decision making for soil fertility and crop yield management. This partially unmet need for reference materials is further exacerbated in low-income/resource settings and limits the frequency with which quality control samples can be routinely analysed: this gap has been specifically identified by the FAO Global Soil Laboratory Network (GLOSOLAN https://www.fao.org/global-soil-partnership/glosolan/en/) capacity strengthening activities. The insufficient supply of appropriately characterised reference materials, particularly soils from tropical sources, has been identified as a limiting factor in the global adoption of effective, harmonised analytical methods. The customer base for new reference materials is potentially broad. In addition to any of the ~1000-strong GLOSOLAN global community of laboratories, other commercial and research laboratories providing agricultural soil sample analyses, in the UK and internationally, as well as academic researchers and PhD students in environmental geochemistry. Existing soil reference materials on the market may present a matrix-matching problem as they are generally milled to <75 μm, as required for total elemental concentration methods. Routine/survey agricultural soil testing is usually undertaken on a more coarse, un-milled sieved fraction, such as <2 mm or <4 mm. This difference in size fraction (especially the changes to particle surfaces caused by additional mineral breakdown during milling) may cause unintended changes to soil texture and, together with an unrepresentative reduction in sample heterogeneity, lead to systematically biased analysis in relation to conventional soil analysis. The use of un-milled soil material for these Reference Materials has avoided such adverse effects that might influence parameter measurement (e.g., pH) or provide enhanced nutrient availability that is itself unrealistic (e.g., available P). Furthermore, extractable (not total) concentrations are used in agriculture to assess the fertility status of soil and make nutrient input decisions appropriate to the next crop. BGS has experience of creating reference materials across a range of rock, sediment, and soil matrices. Ten soil Reference Materials are available (BGS110-BGS119) which are optimised for major, minor and trace element variation from nine contrasting soil parent materials, and one anthropogenically contaminated soil (Kalra et al., 2020). BGS therefore set out to create suite of new reference materials that will help to support high-quality analysis for agriculturally relevant parameters, to augment the soil Reference Materials already offered for sale. This suite comprises a range of sample matrices from temperate silt-rich to peat-rich (BGS120 to BGS124), and equatorial agricultural soils (BGS125 to BGS126). OR/23

An improved approach to characterize potash-bearing evaporite deposits, evidenced in North Yorkshire, United Kingdom

Traditionally, potash mineral deposits have been characterized using downhole geophysical logging in tandem with geochemical analysis of core samples to establish the critical potassium (% K2O) content. These techniques have been employed in a recent exploration study of the Permian evaporite succession of North Yorkshire, United Kingdom, but the characterization of these complex deposits has been led by mineralogical analysis, using quantitative X-ray diffraction (QXRD). The novel QXRD approach provides data on K content with the level of confidence needed for reliable reporting of resources and also identifies and quantifies more precisely the nature of the K-bearing minerals. Errors have also been identified when employing traditional geochemical approaches for this deposit, which would have resulted in underestimated potash grades. QXRD analysis has consistently identified polyhalite (K2Ca2Mg(SO4)4·2(H2O) in the Fordon (Evaporite) Formation and sylvite (KCl) in the Boulby Potash and Sneaton Potash members as the principal K-bearing host minerals in North Yorkshire. However, other K hosts, including kalistrontite (K2Sr(SO4)2) a first recorded occurrence in the UK, and a range of boron-bearing minerals have also been detected. Application of the QXRD-led characterization program across the evaporitic basin has helped to produce a descriptive, empirical model for the deposits, including the polyhalite-bearing Shelf and Basin seams and two, newly discovered sylvite-bearing bittern salt horizons, the Pasture Beck and Gough seams. The characterization program has enabled a polyhalite mineral inventory in excess of 2.5 billion metric tons (Bt) to be identified, suggesting that this region possesses the world’s largest known resource of polyhalite. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution and reproduction in any medium provided that the original work is properly attributed

UK Geoenergy Observatories, Glasgow environmental baseline soil chemistry dataset

This report describes the environmental baseline topsoil chemistry dataset collected in February-March 2018 (03-18) as part of the United Kingdom Geoenergy Observatories (UKGEOS) project. Ninety, samples were collected from the shallow coal-mine Glasgow Geothermal Energy Research Field Site (GGERFS). The report accompanies the GGERFS Soil Chemistry03-18 dataset. It provides valuable information on soil chemistry prior to installation of the GGERFS-facility boreholes, against which any future change during the development/ running of the facility can be assessed. This information is necessary to help understand and de-risk similar shallow geothermal schemes in the future, provide public reassurance, and inform sustainable energy policy

Developments in Pb-210 methodologies to provide chronologies for environmental change

Chronologies generated from core profiles to apply dates to environmental changes commonly use the measurement of the activity of radionuclides deposited and stratified with physical environmental material. The most commonly reported nuclide to define chronologies covering the last 150 years is Pb-210, for which accepted data processing methodologies in the literature have focussed on the constant rate of supply (CRS) model and the more recently published Bayesian Plum model. This short communication describes a validation approach using defined sediment layers referred to as ‘varve’ counting, which provide known points of reference to account for uncertainty between generated dates from each model using published Pb-210 measurements. A significant improvement in the chronologies was observed when applying reference date corrections to the models. This was shown to be essential in providing confidence in reported datasets and accuracy of predicted chronologies, which will better inform the interpretation of environmental change, e.g. sedimentation rates, climate change, pollution pathways and land degradation. Generated chronologies from both the CRS and Plum methods showed good agreement with the established varve dates (typically < 4-year difference)

Analysis of Soil Samples from Kosovo

A number of soil samples were collected from locations in Kosovo by staff of the Defense Evaluation and Research Agency (DERA). Twenty three samples were collected from DERA, Portsmouth and transported in two Aluminium trunks to British Geological Survey (BGS) on 14 February 2001 for geochemical analysis for the determination of lead and uranium and particle size analysis if significant uranium content was encountered. All samples had been screened by gamma ray spectrometry at DERA to identify which samples had significant uranium signatures and were thus likely to be contaminated with depleted uranium. During sampling at one site, VJ Barracks, it was noted that a building close to the sampling sites had had an asbestos roof. Consequently, 8 were identified as having suspicion of containing asbestos, in varying amounts from ‘likely’ to ‘caution required’ (Table 1)

The validation of the detemination of trace elements by energy dispersive polarised X-ray fluorescence spectrometry

This report describes the validation of method AGN 2.1.6 Analysis of Pressed Powder Pellets by Energy Dispersive Polarised X-Ray Fluorescence Spectrometry for its accreditation under UKAS. It includes additional validation carried out on soil samples undertaken to meet the requirements of the MCERTS Standard for submission of data to the Environment Agency