Calculated from calcium and magnesium concentrations:
Total Hardness (mg/l CaCO3 equivalent) = (2.5 x Ca (mg/l)) + (4.12 x Mg (mg/l))
where
2.5 is derived from the molecular weight of CaCO3 (100) / Ca (40)
and
4.12 is derived from the molecular weight of CaCO3 (100) / Mg (24.3)
A number of different publications and standards cite sulphate methods. BR279 (1995) has largely been superseded by analytical procedures as detailed in TRL 447 and BRE Special Digest:1 2005 3rd Edition. In addition further reference may be made to BS EN 144-1:2009 + A1:2012 for the testing of aggregates and BS 1377:2018 for soils for civil engineering purposes.
Testing to meet the requirements of UKWIR Report Ref. No. 10/WM/03/21 Guidance for the selection of water supply pipes to be used in brownfield sites.
Testing & reporting is undertaken in accordance with BS 3882:2015 Specification for topsoil and BS 8601:2013 Specification for subsoil and requirements for use
All Soil Methods
All Water Methods
All Asbestos Methods
All Asbestos Methods
Measurement of the pH of a 2:1 water extract of a dried and ground soil sample using a pH meter.
Measurement of the electrical conductivity of a 2:1 water extract using a conductivity meter.
Determination of the proportion by mass that is lost from a soil by ignition at 440°C or 550°C.
Measurement of the electrical conductivity using a conductivity meter.
Electrometric determination (on site preferred), using an oxygen sensitive membrane electrode.
Automated colorimetric analysis by a discrete analyser using 1,5-diphenylcarbazide.
