Sampling Techniques to Ensure Quality Results. David Springer ACLCA Adelaide June 2013

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1 Sampling Techniques to Ensure Quality Results David Springer ACLCA Adelaide June 2013

2 Tonight Measurement Uncertainty Poor Sampling Examples NEPM Preservations/Holding Times NEPM TRH v s TPH NEPM F1/F2 NEPM BaP TEQ NEPM WA Asbestos NEPM B7 Transport of Samples Ice Acknowledgement Thanks to ALS for assisting with some information

BaP TEQ NEPM WA Asbestos NEPM B7 Transport of Samples Ice

3 Measurement Uncertainty (MU) A parameter associated with the result of a measurement that characterises the dispersion of the values that could reasonably be attributed to the measurand (international vocabulary of basic & general terms in metrology)

the values that could reasonably be attributed to the

4 Simple Definition of MU Basically how sure is the lab of the result? It is a range containing the true value with a stated level of confidence eg: Lead in soil has a MU of 10%. We test a soil & report to you 20 mg/kg. We are 95% confident that the concentration of Lead is somewhere between 18mg/kg & 22mg/kg

eg: Lead in soil has a MU of 10%. We test a soil & report to you 20 mg/kg.

6 How to Calculate various ways Precision and Bias Last resort professional judgement Analyte MU % Alkalinity 21 Chloride 15 Sulfate 17 Nitrate 14 Nitrite 13 TSS 16 ph 3 Aluminium 18 Cobalt 21 Mercury 16

Alkalinity 21 Chloride 15 Sulfate 17 Nitrate 14

7 MU continued Depends on matrix and PQL eg: OC to 0.001ppm = 80%, to 0.1ppm = 15% Small uncertainty reliable Large uncertainty caution may be appropriate Biggest contributor to MU is sampling!

8 Conundrum Lab reports 1 mg/l for Lead Guideline value is 1mg/L Lab MU is 10% (ie: mg/l) Is your result over the limit?

9 Our results are only as good as your Sampling. If you don t get the sampling right, the testing may be a waste of money and your interpretations will be flawed.

10 How much do we actually take? 250g soil jar 10g PAH 5g BTEX 3g Metals 40g Asbestos

11 Foundry Soil

12 Lead not too bad Pb mg/kg mg/kg Series samples

13 Copper - OK Cu mg/kg mg/kg Series samples

14 Chromium non homogenous 300 Cr mg/kg Series mg/kg sample

15 Pb in top 60mg/kg, Pb in bottom <1mg/kg

16 Not the best

17 Water - Field Duplicates

18 Water Field Duplicates

19 Duplicates? Apparently Yes!

20 Acidification of Metals 120 The Effect of Time on the Co-precipitation of Metals in a Neutralised Solution Containing 10 ppm Iron and 100ppb of Each Analyte. Zn Co Ni Cu Cd Pb ppb in solution Elapsed Time (hrs)

Containing 10 ppm Iron and 100ppb of Each Analyte.

21 Filter v no filter - Fe Dropped out of solution

22 Always take a good QC sample

23 BaP (PAH) Duplicate - <0.1mg/kg top, 5mg/kg bottom

24 Hg Hotspots Lab Duplicate was 4 & 40 mg/kg

25 NEPM Changes Analyte Container Holding Time Old NEPM Holding Time NEW NEPM Cyanide P, PTFE, G 7 days 14 days Fluoride P, G 7 days 28 days Metals P (old) P/G (new) 6 months 6 months Mercury P (also Cr6) P 28 days 28 days (7 days Hex) VOC (except below) G 14 days 14 days Vinyl chloride, styrene, 2-chloroethyl vinyl ester G 14 days 7 days

26 TPH v TRH 2 new methods TRH and TRH (silica) No longer referred to as TPH All labs will now extract/analyse/calculate/report the same way Advantages of New Fractions More info to make reasonable risk assessments Gains of New Method Standardisation of banding amongst labs = more consistent data Tightening of performance requirements The Term TRH is equivalent to the historically reported TPH

27 Banding Volatile (vtrh) Was C6-C9 Now C6-C10 Semi Volatile (svtrh) Was C10-C36 Now >C10-C40 Petrol, light fuel, petroleum based solvents Diesel, other petroleum fuels, mineral oils and petroleum based solvents

28 Semi Volatile Fractions Fractions >C10 C16 >C16 C34 >C34 C40 Interferences TRH includes any organic compounds that are soluble in the relevant solvent(s) and elute under a linear GC program method conditions. Can include vegetable & animal oils, fats, plasticisers and solvents i.e. Biogenic plus any Petrogenic hydrocarbons The use of silica gel to adsorb polar compounds may reduce potential false positives from Biogenic material thus yielding a result more reflective of any petroleum contamination (where applicable).

29 What is Silica Gel Cleanup After a sample is extracted in solvent the solvent extract is poured through a column containing silica gel (or can be mixed in the extraction vessel directly). The solvent extract runs down through the column slowly, over the surface of the silica gel particles. The silica gel retains the more polar compounds that were co-extracted from the sample, allowing the less polar petroleum based compounds to flow through ready for GC-FID analysis. Note, Silica Gel analysis is only applicable to semi-volatile fractions.

30 Diesel spiked Woodchips - TRH C10-C14 : 410ppm C15-C28: 1500ppm C29-C36 : 600ppm Diesel spiked Woodchips - TRH Silica Gel cleaned C10-C14 : 380ppm C15-C28 : 910ppm C29-C36: 140ppm The last 2 fractions yield a lower result after the silica gel cleanup, emphasizing the importance of determining TRH Silica Gel where Biogenic material can lead to false positives. The term TRH-Silica is used as the separation of petrogenic and biogenic is not absolute!

31 Banding Old v New NEPM Old TPH Band Reporting C10-C14: C>9-C14 : 180ppm C15-C28: C>14-C28 : 280ppm C29-C36: C>28-C36 : <PQL New TRH Band Reporting >C10-C16: 270ppm >C16-C34: 190ppm >C34-C40 : <PQL The banding is now defined specifically in NEPM B3 with respect to certain n-alkane markers and must be adhered to!

32 F1, F2 In order to compare to HSLs, F1 and F2 are defined as:- F1 = C 6 -C 10 less BTEX (as BTEX HSLs characterised) F2 = >C 10 C 16 less Naphthalene (as Naphthalene HSL characterised) From NEPM B1 (CCME)

33 F1, F2 continued F2 = >C 10 C 16 less Naphthalene Napthalene for this subtraction will be taken from the BTEX analysis (due to BTEX generally being run with TRH). Most labs will do this, though NEPM does not say! Otherwise, a separate PAH run (and charge) would possibly occur. Always subtraction from BTEX run, even if PAH s are done keep consistent. Napthalene by P&T (BTEX) v s Napthalene by GC-MS Soils different extraction (methanol v DCM-Acetone), different instrumentation Waters different preservatives, different instrumentation

34 WA Asbestos WA method = 10x more conservative than the Netherlands to account for dryer Australian soils WA = 0.001% asbestos in soil for FA (Fibrous Asbestos) & AF (Asbestos Fines) However, 0.01% remains the standard LOR for AS4964 method The examination of 500ml may improve the likelihood of identifying asbestos Any reporting of <0.01% MUST be NON NATA Further info TBA

35 WA Asbestos A positive result would normally be considered by DOH to exceed the 0.001% w/w investigation criteria applied to fine asbestos material, especially given that a 0.01% LOD usually applies. However, a single such exceedance may not necessarily result in the sample source being deemed contaminated. A weight of evidence approach should be used by the consultant, auditor and regulator in assessing the significance of an exceedance, which should take account of the history of the site and frequency and occurrence of other positive and negative results.

36 Schedule B7 Free Cyanide HIL has been derived for Free Cyanide However, the measurement of Free CN is difficult So, Schedule B3 recommends WAD CN as a conservative measure of Free CN.

37 Schedule B7 (Table 1A(1) HIL) - Mirex Phased out of Australia in 2007 Prior to 2007, only used in NT for Giant Termite Control in Mango Trees Never Detected before in Australian Food (FASANZ 2001) No Background concentration data available in Australia

38 Schedule B7 - (Table 1A(1) HIL) - Toxaphene Mainly available 1940 s to 1980 s Still used in some parts of Africa and Asia Mainly used in Cotton, Grains, Fruits/Veg, Nuts, Cattle NEVER USED in AUSTRALIA!

39 Benzo (a) Pyrene TEQ B(1) includes HIL s for BaP as Toxic Equivalents (TEQ) This is the comparison of 8 carcinogenic PAH s relative to BaP Labs will do this calculation for you

40 Sample Transport Old NEPM Ice or 4 degree refrigerated transport New NEPM Preferably ice bricks or refrigerated container ELIG preferred option has always been Cool samples in either fridge or ice Then - transport to lab with ice bricks or double-bagged ice (not free flowing ice) Free flowing ice can easily melt, and potentially contaminate your samples.

41 Potential Cross Contamination

42 Potential Cross Contamination?

43 Hydrocarbon Contamination?

44 Cairns to Sydney does need Bubble Wrap!

45 Floating in Ice Mud

46 Ice water penetration - contamination

47 Esky Ice water

48 esky water Al = 200,000 ppb As = 35 ppb Cd = 7 ppb Co = 930 ppb Cu = 3700 ppb Fe = 600,000 ppb Pb = 120 ppb Mn = 55,000 ppb Ni = 450 ppb U = 24 ppb

49 esky water + sampling rubbish Al = 6000 ppb Cu = 15 ppb Fe = 7500 ppb Pb = 40 ppb Mn = 60 ppb Zn = 80 ppb Ba = 120 ppb Sn = 20 ppb V = 10 ppb

50 Metals (total) in melted esky ice Sydney Sydney Country NSW Sydney West NSW Aluminium (ppb) 1, ,000 5,700 22, Arsenic (ppb) Cadmium (ppb) < Chromium (ppb) Cobalt (ppb) <1 Iron (ppb) 1, ,000 7,500 24, Lead (ppb) Zinc (ppb) Manganese (ppb) ,

51 Duct Tape Sealed Bottles

52 Duct Tape Sealed Bottles The melted ice water was analysed for VOC s: Toluene = 520 ppb (detection limit is 1 ppb)

53 Red Texta Stained Ice Water (from label ID s)

54 Texta Water VOC Analysis Benzene = 20 ppb Toluene = 190 ppb Ethyl Benzene = 2 ppb Xylenes = 4 ppb (Detection limit is 1µg/L = 1ppb)

55 Esky ice with a sheen?

56 Esky ice with a sheen - results Benzene = 2,100ug/L Xylenes 4,300 ug/l Napthalene = 240 ug/l C10-C14 TRH = 7,000 ug/l C15-C28 TRH = 6,600 ug/l

57 What s the Solution? Cool samples in ice/fridge then transport with ice bricks Use ice, but double bag it. Don t leave it free flowing.

58 What the Lab needs from you Clearly written and correct COC s (PB won our 2012 $500 prize for consistently good COC s). Over 50% of all COC s have issues Correct sampling right bottles, metals filtered if needed (and ticked) Samples packed to avoid breakages Samples packed to avoid cross contamination Any doubts just ask the lab. We don t mind.

59 Asbestos or Soil?

60 Well, I guess we do ask for a separate bag!

61 No Ice Bricks? At least they made the effort!

62 Started a trend?

63 Again?

64 Ice Brick Fail!

65 Bacon Brick? Fail. (the note says `sorry about the bacon J )

66 As an Industry lets get rid of Bad Ice

67 And only use Good Ice Photo: Tom Raftery

TERRA TEK LIMITED GUIDE TO SAMPLE HANDLING. Version 1.06

TERRA TEK LIMITED GUIDE TO SAMPLE HANDLING Version 1.06 September 2009 Guidance on Sample Containers & Storage Conditions - SOIL SAMPLES 500ml Plastic Tub Suitable for: Inorganic Parameters, usually sufficient