Dr. John Ashworth Senior Soil Scientist Analytical and regulatory requirements for barium in soils and drilling wastes

2012 D-50 Trace ElementGuideline Value (mg/kg) Agricultural Land Use Natural Area Land UseParkland Land Use Antimony20 Arsenic (inorganic)17 Barium Barite-barium10,000 Beryllium555 Boron (hot water soluble)222 Cadmium Chromium (total)64 Chromium (hexavalent)0.4 Cobalt20 Copper63 Lead Mercury (inorganic) Molybdenum444 Nickel50 Selenium111 Silver20 Thallium111 Tin555 Vanadium130 Zinc200

Typically a mixture of water and clay, drilling fluids (mud) may contain other additives. Barite is a commonly added weighting agent, used to improve the viscosity and density of the fluid, to counterbalance the formation pressure as well as carry cuttings to the surface.

L Sample ID DescriptionSALM Ba mg/kg - 4Pit D solids Clay soil :1 mix 2, :1 mix 2, :1 mix 2,600

Society of Petroleum Engineers and International Association of Drilling Contractors (SPE/IADC) Paper by Deuel and Freeman, read at SPE/IADC Conference in New Orleans, Louisiana “Efforts to close existing pits within on-site criteria have been frustrated by unexpected problems with Ba. Treatment often included dilution techniques whereby waste materials are incorporated into the native soil. Operators have observed, in many cases, higher Ba levels following treatment than initially.” “It was suggested from the experiments and surveys in this study that the strong acid digest Ba level is not a reliable index for regulatory purposes. It is recommended that Ba be regulated from a “true” total metal analysis perspective.” (Feb. 1989)

L Sample IDDescriptionSALM Ba mg/kgXRF (total Ba) data - 4Pit D solids 620 (mg/kg) - 5Clay soil :1 mix (R=3) 2, :1 mix (R=5) 2, :1 mix (R=7) 2,600 99,000 1,400 19,000 12,500 9,700 Ba mix = [ Ba waste x DBD + Ba soil x R x 1540 ] / [ DBD + R x 1540 ] For this waste, DBD was approx. 1,000 g/L, based on SG = 1.6 All total Ba results (XRF data) in the Table agree with values predicted by the D-50 weighted-average formula R = mix ratio. DBD = waste dry bulk density. Typical soil density = 1540 g/L

Axiom Environmental, 2004 (Miles Tindal)

Province Confirm “barite waste” by: Analyze waste for Ba by: Alberta Weak calcium chloride test Total Ba method (XRF, or fusion ICP)

Read-out Total Ba Non-destructive Instantaneous X-rays Ba Detector XRF method Ba Fusion-ICP method Agitate crucible + flux with acid 2 Ba ICP spectrometer 3 Ba Muffle furnace, 1000 C 1 Solid sample + Li borate in graphite crucible

Katanax auto fluxer

Fusion procedure (soil + 250,000 ppm barite) OxidizerBa recovery Pt crucible + Li borate in auto- fluxer at 1000 ⁰C (followed by dissolution in acid) Li nitrate10 % Tungsten oxide9 % V2O5V2O5 4 % Graphite crucible + Li borate in muffle at 1000 ⁰C None % Pt crucible + Li borate in muffleNone60 % Pt crucible + Li borate in auto- fluxer Charcoal33 % BaSO 4 = BaO + SO 3 BaO + 2HNO 3 = Ba(NO 3 ) 2 + H 2 O BaSO 4 + 4C = BaS + 4CO BaS + 2HNO 3 = Ba(NO 3 ) 2 + H 2 S

Crucibles are arranged in a listed order Placed in same order in muffle furnace 0.20 g soil g each of Li metaborate & tetraborate (Note: no oxidizing agent) 2BaSO 4 + C + 2H 2 O = 2Ba(OH) 2 + CO 2 + 2SO 2 Ba(OH) 2 + 2HNO 3 = Ba(NO 3 ) 2 + 2H 2 O

Province Confirm “barite waste” by: Analyze waste for Ba by: Alberta Weak calcium chloride test Total Ba method (XRF, or fusion ICP) British Columbia DocumentationStrong calcium chloride test