Total Residue (Total Solids, TS) in Aqueous Matrices TS Method.pdf · Total Residue (Total Solids, TS) in Aqueous Matrices Environmental Express . 2345A Charleston Regional Parkway

Total Residue (Total Solids, TS) in Aqueous Matrices

Environmental Express

2345A Charleston Regional Parkway

Charleston, SC 29492

800-343-5319

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Table of Contents 1. Scope and Application ............................................................................................................. 3

2. Summary of Method ................................................................................................................ 3

3. Definitions ............................................................................................................................... 3

4. Interferences ............................................................................................................................ 4

5. Safety ....................................................................................................................................... 4

6. Equipment and Supplies .......................................................................................................... 5

7. Reagents and Standards ........................................................................................................... 6

8. Sample Collection Preservation and Storage........................................................................... 6

9. Quality Control ........................................................................................................................ 6

Table 1: 40 CFR part 136.7 Quality Control Requirements ................................................... 6

10. Procedure ............................................................................................................................... 10

11. Data Analysis and Calculations ............................................................................................. 10

12. Method Performance ............................................................................................................. 11

13. Pollution Prevention .............................................................................................................. 11

14. Waste Management ............................................................................................................... 11

15. References ............................................................................................................................. 11

16. Tables, Diagrams, Flowcharts, and Validation Data ............................................................. 12

Table A1: LRB Stable Weigh Blank, Oven ...................................................................... 13

Table A2: LRB Stable Weigh Blank, Hot Block .............................................................. 14

Table A3: LFB Low Inorganic Standard TS Stable Weigh Oven .................................... 15

Table A4: LFB Low Inorganic Standard TS Stable Weigh Hot Block ............................ 16

Table A5: LFB Low Inorganic Standard TS Evaporation Dish ....................................... 17

Table A6: LFB High Inorganic Standard TS Stable Weigh Oven.................................... 18

Table A7: LFB High Inorganic Standard TS Stable Weigh Hot Block ............................ 19

Table A8: LFB High Inorganic Standard TS Evaporation Dish ....................................... 20

Table A9: Biosolids, Drying Oven, Stable Weigh ............................................................ 21

Table A10: Biosolids, Hot Block, Stable Weigh .............................................................. 22

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Table A11: Biosolids, Drying Oven, Evaporation Dish ................................................... 23

Table A12: StableWeigh and Porcelain Evaporation Dish Precision ............................... 24

Table A13: StableWeigh Laboratory Reagent Blank Percent Variance ........................... 25

Table of Figures Figure 1: Initial Demonstration of Capability Calculation ............................................................. 7

Figure 2: LRB Calculation .............................................................................................................. 8

Figure 3: LFB Calculation .............................................................................................................. 8

Figure 4: RPD Calculation .............................................................................................................. 8

Figure 5: Total Solids Calculation ................................................................................................ 10

Figure 5: LFB IDC Low Inorganic Standard TS Stable Weigh Oven .......................................... 26

Figure 6: LFB IDC Low Inorganic Standard TS Stable Weigh Hot Block .................................. 27

Figure 7: LFB IDC Low Inorganic Standard TS Evaporation Dish ............................................. 28

Figure 8: LFB IDC High Inorganic Standard TS Stable Weigh Oven ......................................... 29

Figure 9: LFB IDC High Inorganic Standard TS Stable Weigh Hot Block ................................. 30

Figure 10: LFB IDC Low Inorganic Standard TS Evaporation Dish ........................................... 31

Figure 11: IDC Biosolids, Drying Oven, Stable Weigh ............................................................... 32

Figure 12: IDC Biosolids, Hot Block, Stable Weigh .................................................................... 33

Figure 13: High Inorganic Standard Averages vs. Standard Value .............................................. 34

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1. Scope and Application

1.1. This method is based upon Standard Methods 2540 for the determination of Total Residue in aqueous sample matrices.

1.2. This method is for use in the Environmental Protection Agency’s (EPA’s) data gathering and monitoring programs under the Clean Water Act, the Resource Conservation and Recovery Act, the Comprehensive Environmental Response, Compensation and Liability Act, and the Safe Drinking Water Act.

1.3. This method is used to determine Total Residue (Total Solids, TS).

1.4. This method is applicable to drinking, surface, and saline waters, domestic and industrial wastes

1.4.1. The concentration range for this method is determined by the minimum and maximum residue mass allowed (2.5 – 750 mg) and the volume of sample needed to achieve the desired residue mass. Samples for TS have no upper volume limit specified but are limited by the size of the evaporation vessel and the practicality of repeated additions of sample volume.

1.5. Each laboratory that uses the method must demonstrate the ability to generate acceptable results.

2. Summary of Method

2.1. For TS the entire aliquot of sample is evaporated in a pre-weighed vessel and dried to constant weight at 104 ± 1°C. The mass of the residue is determined by difference in mass of the vessel.

3. Definitions

3.1. Laboratory Fortified Blank (LFB) - An aliquot of reagent water or other blank matrix to which known quantities of the method analytes and all the preservation compounds are added. The LFB is processed and analyzed exactly like a sample, and its purpose is to determine whether the methodology is in control, and whether the laboratory is capable of making accurate and precise measurements.

3.2. Laboratory Matrix/Duplicate (LM/LMD) also called Matrix / Duplicate (M/D): An aliquot of an environmental sample and a duplicate which are analyzed and its purpose is to determine whether the sample matrix contributes bias to the analytical results.

3.3. Laboratory Reagent Blank (LRB) - A volume of reagent water or other blank matrix that is processed exactly as a sample including exposure to all glassware and equipment, that are used in the analysis batches. The LRB is used to determine if the method analytes or

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other interferences are present in the laboratory environment, the reagents, or the apparatus.

3.4. Minimum Reporting Level (MRL) - The minimum concentration that can be reported by a laboratory as a quantitated value for a method analyte in a sample following analysis. This concentration must not be any lower than the concentration of the lowest calibration standard for that instrument.

3.5. Total Residue or Total Solids is defined as all material that is not volatile at 104°C.

3.6. Water Sample: For the purpose of this method, a sample taken from one of the following sources: drinking water, surface water, storm runoff, industrial or domestic wastewater.

4. Interferences

4.1. Samples with multiple phases or those that settle into multiple layers present a problem with homogeneity. Ensure that such samples are well mixed during use. Vigorous shaking through inversion will provide a sufficient mixing for most samples. Samples that settle rapidly or resist mixing may require constant stirring with a magnetic stirrer. Use a wide bore pipette in such instances. Draw sample from the midpoint between the wall and the vortex. Avoid using propeller style mixers as these may shear particles resulting in underreported values.

4.2. Some samples may form a crust during drying. This crust can prevent some evaporation of water during the drying process. If a water trapping crust continues to be problematic reduce the amount of sample used to minimize the crust being formed or take other steps to allow water to evaporate. Document additional steps being used as well as the precautions that are taken to avoid loss of residue from the dried sample.

4.3. Organic compounds such as oil and grease may present problems in obtaining a stable final weight. Such compounds are often visible to the naked eye and well present as a constantly decreasing mass after each drying event. Develop a Quality Plan to positively identify these types of samples. Obtain a value for HEM for such samples, if possible and consult with the final data user how to use that value in conjunction with the data obtained from the analysis.

5. Safety

5.1. When working with and around ovens or other evaporation equipment the materials in use will become hot. Use appropriate heat resistant gloves and other necessary PPE to protect the analysts from exposure to heat. Different temperatures may require different PPE to be effective.

5.2. Use all standard PPE (gloves, safety glasses, lab coats, etc.) as required by your Laboratory Safety and Chemical Hygiene Plan. Pay particular attention to samples of

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unusual appearance or odor and request additional information from the sample source as necessary to identify unknown or unexpected hazards.

5.3. This method does not address all safety issues associated with its use. The laboratory is responsible for maintaining a safe work environment and a current awareness file of OSHA regulations regarding the safe handling of the chemicals specified in this method. A reference file of safety data sheets (SDS’s) must be available to all personnel involved in these analyses.

6. Equipment and Supplies

Note: Brand names, suppliers and part numbers are cited for illustrative purposes only. No endorsement is implied. Equivalent performance may be achieved using equipment and materials other than those specified here, but demonstration of equivalent performance that meets the requirements of this method is the responsibility of the laboratory.

6.1. Evaporation Vessel – StableWeigh™ TDS Vessel from Environmental Express, or equivalent. This vessel is not suitable for use in volatile solids determination. In such instances use ceramic, high silica glass, or platinum evaporating dishes of appropriate dimensions. When using the StableWeigh™ product, other accessories are recommended or required for ease of use.

6.2. StableWeigh™ modular rack – recommended. Used to transport and hold StableWeigh™ Vessels to, from, and in ovens and desiccators.

6.3. StableWeigh™ weighing bracket – recommended. Used to support vessels on the balance.

6.4. Static electricity dissipation device. Best results have been achieved using the Mettler Toledo balance deionizer or similar device. Mounted anti-static ionizing cartridges or brushes can be effective if care is taken to ensure the entire vessel is appropriately treated.

6.5. Drying oven for use at 103-105°C.

6.6. Dessicator with dessicant– must include some indicator to determine when replacement of the desiccant is necessary. This can be indicating desiccant or other appropriate means.

6.7. Analytical balance capable of accurate and precise weighing to 0.1 mg.

6.8. Class A Graduated Cylinders or Class B Wide Tip Pipets measuring devices of appropriate volume to measure necessary amounts of sample.

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7. Reagents and Standards

7.1. The various forms of residue are determined based solely on physical characteristics. No specific chemicals or reagents are required for this analysis.

7.2. No specific standard is required. The Universal Solids Standard from Environmental Express or equivalent may be used TS. This standard is intended to be used only as a whole volume standard and may not be subsampled. Alternatively, weigh out a non-soluble substance such as diatomaceous earth in an amount near the range of your samples and add it to an appropriate volume of water.

8. Sample Collection Preservation and Storage

8.1. Always refer to the latest guidelines in 40 CFR part 136 for sampling guidelines, preservation guidelines, and holding time. Those instructions supersede any guidance given in this document.

8.2. Collect sample in a plastic or glass bottle. A recommended volume is a minimum of 250 mL.

8.3. Store samples at ≤ 6°C when not in use.

8.4. Store samples for no more than 7 days from collection.

9. Quality Control

9.1. Each laboratory that uses this method is required to develop and implement a formal Quality Manual. The minimum requirements of this program are outlined in 40 CFR part 136.7.

Table 1: 40 CFR part 136.7 Quality Control Requirements

40 CFR 136.7 QC Requirement Required (Yes/No) and Notes

Demonstration of Capability (DOC), Initial and Ongoing Demonstration of Capability Required

Method Detection Limit (MDL), MDL Spike and MDL Blank not required for methods defined test.

Laboratory reagent blank (LRB), Required daily or with each batch of 20 or fewer samples.

Laboratory fortified blank (LFB), also referred to as a spiked blank, or laboratory control sample (LCS),

LFB is required daily or with each batch of 20 or fewer samples.

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Table 1: 40 CFR part 136.7 Quality Control Requirements

40 CFR 136.7 QC Requirement Required (Yes/No) and Notes

Matrix spike (MS), matrix spike duplicate (MSD), or laboratory fortified blank duplicate (LFBD) for suspected difficult matrices,

Duplicates daily or with each batch of 20 or fewer samples.

Internal standard/s, surrogate standard/s (for organic analysis) or tracer (for radiochemistry), Not required.

Calibration (initial and continuing), Calibrate balance as per manufacturer and regulatory requirements.

Control charts (or other trend analyses of quality control results), Required.

Corrective action (root cause analyses), Required.

Specific frequency of QC checks, Required.

QC acceptance criteria, and Required.

Definitions of a batch (preparation and analytical) Required.

Note: Daily: Each day samples are analyzed in the laboratory.

9.2. Initial Demonstration of Capability (IDC)

9.2.1. Before new analysts run any samples, verify their capability with the method. Run a LFB at least four times. Calculate the standard deviation of the four samples. All 4 LFB values must fall within the LFB recovery limits for the analyst to pass the IDC

( )LFB’s initial recovery limits = Mean ± 5.84 × Standard DeviationWhere:

5.84 = the two-sided Student’s t factor for three degrees of freedom.

Figure 1: Initial Demonstration of Capability Calculation

9.3. Laboratory Reagent Blank (LRB):

9.3.1. High quality laboratory water that is analyzed as a sample. Analyzed at a frequency of no less than once per sample batch. Develop control chart limits to determine acceptable recovery. Perform Root Cause Analysis as per the laboratory Quality Manual in recovery is unacceptable.

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LRB= LRB Concentration determined experimentally

ExperimentalValueExperimentalValue

=

Figure 2: LRB Calculation

9.4. Laboratory Fortified Blank (LFB):

9.4.1. LFB can :

9.4.1.1. Be purchased from a 3rd party supplier such as Environmental Express. Follow supplier’s directions or:

9.4.1.2. Prepare in a 1000 ml volumetric flask put 0.2500 g (± 0.0001 g) of Celite and 20.0000 g (± 0.0001 g) of Sodium Chloride. Dilute to volume with DI water and mix well. Transfer 10 ml of the LFB to a StableWeigh vessel and dry. Recovery will be 20.2500 g/L.

9.4.1.3. A maximum recovery range of 80% to 120% is expected. Develop control chart limits to determine acceptable recovery. Perform Root Cause Analysis as per the laboratory Quality Manual in recovery is unacceptable.

Experimental Value *100= Percent Recovery LFBExpected Value

Experimental Value = LFB Concentration determined experimentallyExpected Value = Known LFB concentration

Figure 3: LFB Calculation

9.5. Laboratory Matrix/ Laboratory Matrix Duplicate (LM/LMDD):

9.5.1. A duplicate set of TS samples are analyzed. LM/LMD are analyzed at a frequency of no less than once per sample batch. A Relative Percent Difference (RPD) will be calculated for each LM/LMD set. Develop control chart limits for RPD to determine acceptable recovery. Perform Root Cause Analysis as per the laboratory Quality Manual in recovery is unacceptable.

( )LM-LMDAbsolute Value *100 = RPD

LM+LMD2

LM = Concentration determined for LMLMD = Concentration determined for LM duplicate

Figure 4: RPD Calculation

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9.6. Ongoing Demonstration of Capability

9.6.1. Samples consisting of the LRB, LFB, and LM/LMD will be runr each batch of samples. These results will be charted on control charts to determine ODC for the laboratory. Develop control chart limits to determine acceptable recovery. Perform Root Cause Analysis as per the laboratory Quality Manual in recovery is unacceptable.

9.7. Balance Check. An appropriate check weight should be evaluated at the beginning and end of each weighing sequence. The checks will demonstrate lack of drift in the balance. Reasonable choices would be within the same order of magnitude as the expected mass of the residue plus StableWeigh vessel used for the samples. Develop control chart limits to determine acceptable check weight. Perform Root Cause Analysis as per the laboratory Quality Manual in check weight is unacceptable.

9.8. Sample Batch

9.8.1. A group of samples which behave similarly with respect to the sampling or the testing procedures being employed and which are processed as a unit. For QC purposes, if the number of samples in a group is greater than 20, then each group of 20 samples or less will all be handled as a separate batch. A batch cannot span between laboratory work days (24 hrs.). New batches must be started each laboratory work day.

9.8.2. Sample Batch: Typical sample analysis sequence.

9.8.2.1. Balance Check

9.8.2.2. LRB

9.8.2.3. LFB

9.8.2.4. LM

9.8.2.5. LMD

9.8.2.6. Samples

9.8.2.7. Balance Check

9.9. Other Equipment Checks

9.9.1. Other equipment used in this analysis, such as ovens, balances, and thermometers, must be maintained and checked as required by the laboratory Quality Manual.

9.10. Control charts and trend analysis will be performed on all areas identified in the Quality Control section in this method and in the laboratories Quality Manual.

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10. Procedure

Note: This method is entirely empirical. Acceptable results can be obtained only by strict adherence to all details.

10.1. Select an appropriate number of StableWeigh TDS vessels for the required number of samples and QC. Assign each vessel to a sample and note the vessel tare weight in the appropriate analysis data log. StableWeigh vessels must not be used if the sample aliquot is to be analyzed for volatile solids.

10.2. Choose a sample volume expected to yield a residue between 2.5 and 750 mg. Mix the sample well through appropriate means (repeated inversion, stirring with magnetic stirrer or other) and measure out the appropriate sample volume. Add the sample volume to the evaporation vessel. If the vessel is not of sufficient size to hold the volume required, successive portions of sample may be added after evaporation.

10.3. Evaporate the sample to dryness using a block digester, oven, steam bath, or other appropriate method. Set the evaporation temperature low enough that the samples do not boil and splatter.

10.4. Dry the evaporated sample and vessel in a drying oven at 104 ± 1°C for at least one hour.

10.5. Remove the vessels from the oven and place in a dessicator until they have reached balance temperature.

10.6. Weigh each vessel on the balance and record the weight to 0.1 mg.

10.7. Repeat steps 11.1.4 - 11.1.6 at least one more time and as many times as necessary to obtain consecutive weights that differ by less than 0.5 mg. QC samples must go through the drying/cooling/weighing cycle as long as other samples require them. Other samples may be removed from the cycle once they have shown weight stability.

11. Data Analysis and Calculations

11.1. Calculations for Total Solids

( )

A = Weight of dried sample + StableWeigh (mg)B = Weight of StableWeigh (m

A-B x1000= TotalSo

g)C = volume of

lids (mg/

sample

L)C

(mL)

Figure 5: Total Solids Calculation

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12. Method Performance

12.1. See Standard Methods 2540 for performance data on the original analysis method.

12.2. Comparison data validating the use of the StableWeigh vessel in comparison to the crucibles required for TS are found in Tables/Appendices.

13. Pollution Prevention

13.1. The main source of pollution from this method is from unknown samples. Follow your laboratory Waste Management Program for the identification and disposal of potentially hazardous samples.

14. Waste Management

14.1. It is the laboratory's responsibility to comply with all federal, state, and local regulations governing waste management, particularly the hazardous waste identification rules and land disposal restrictions, and to protect the air, water, and land by minimizing and controlling all releases from fume hoods and bench operations. Compliance with all sewage discharge permits and regulations is also required.

14.2. Use the least amount of sample possible to generate valid results, particularly for TS. This will minimize the amount of waste generated by the analysis.

14.3. For further information on waste management, consult "The Waste Management Manual for Laboratory Personnel," and "Less is Better: Laboratory Chemical Management for Waste Reduction," both available from the American Chemical Society's Department of Government Relations and Science Policy, 1155 16th Street N.W., Washington DC, 20036.

15. References

15.1. Eaton, A. D., Clesceri, L. S., Baird, R. B., Rice, E. W., American Public Health Association., American Water Works Association., & Water Environment Federation. (2012). Standard Methods for the Examination of Water and Wastewater, 22nd edition. Washington, DC: American Public Health Association

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16. Tables, Diagrams, Flowcharts, and Validation Data

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Table A1: LRB Stable Weigh Blank, Oven

Sample # Volume (ml)

Initial weight

(g)

Final weight 1

(g)

Final weight 2

(g)

Final weight 3

(g)

Two Consecutive

Weights Difference

(mg)

Final weight used (mg)

Percent Change

1 25 3.9073 3.9075 3.9079 0.4 3.9079 0.01536% 2 25 3.8838 3.8848 3.8851 0.3 3.8851 0.03347% 3 25 3.9673 3.9673 3.9675 0.2 3.9675 0.00504% 4 25 3.6667 3.6667 3.6668 0.1 3.6668 0.00273% 5 25 3.6966 3.6969 3.6972 0.3 3.6972 0.01623% 6 25 3.6898 3.6897 3.6902 0.5 3.6902 0.01084% 7 25 3.7101 3.7100 3.7105 0.5 3.7105 0.01078% 8 25 3.6792 3.6790 3.6792 0.2 3.6792 0.00000% 9 25 3.7136 3.7134 3.7134 0.0 3.7134 -0.00539% 10 25 3.6771 3.6775 3.6779 0.4 3.6779 0.02176%

Average 0.01108%

Standard Deviation 0.01136%

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Table A2: LRB Stable Weigh Blank, Hot Block

Sample # Volume (ml)

Initial weight

(g)

Final weight 1

(g)

Final weight 2

(g)

Final weight 3

(g)

Two Consecutive

Weights Difference

(mg)

Final weight used (mg)

Percent Change

1 25 3.7370 3.7390 3.7389 -0.1 3.7389 0.05084% 2 25 3.7109 3.7126 3.7122 -0.4 3.7122 0.03503% 3 25 3.6983 3.7000 3.6996 -0.4 3.6996 0.03515% 4 25 3.7418 3.7432 3.7428 -0.4 3.7428 0.02673% 5 25 3.7066 3.7080 3.7078 -0.2 3.7078 0.03237% 6 25 3.8762 3.8772 3.8773 0.1 3.8773 0.02838% 7 25 3.9364 3.9380 3.9376 -0.4 3.9376 0.03048% 8 25 3.8830 3.8840 3.8838 -0.2 3.8838 0.02060% 9 25 3.9131 3.9146 3.9141 -0.5 3.9141 0.02556% 10 25 3.9127 3.9138 3.9135 -0.3 3.9135 0.02045%

Average 0.03056%

Standard Deviation 0.00883%

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Table A3: LFB Low Inorganic Standard TS Stable Weigh Oven

Sample # Bag # Volume

(ml)

Initial weight

(g)

Final weight 1

(g)

Final weight 2

(g)

Final weight 3

(g)

Two Consecutive

Weights Difference

(mg)

Final weight used (mg)

Final Solids Recovered

Weight (mg)

Percent Recovery

1 1 25 3.9096 3.9676 3.9676 0.0 3.9676 58.0 100.00% 2 2 25 3.6663 3.7238 3.7237 -0.1 3.7237 57.4 98.97% 3 3 25 3.8910 3.9483 3.9482 -0.1 3.9482 57.2 98.62% 4 4 25 3.8949 3.9521 3.9521 0.0 3.9521 57.2 98.62% 5 5 25 3.6003 3.6570 3.6570 0.0 3.6570 56.7 97.76% 6 6 25 3.8687 3.9254 3.9251 -0.3 3.9251 56.4 97.24% 7 7 25 3.5858 3.6423 3.6420 -0.3 3.6420 56.2 96.90% 8 8 25 3.9043 3.9612 3.9608 -0.4 3.9608 56.5 97.41% 9 9 25 3.9007 3.9568 3.9565 -0.3 3.9565 55.8 96.21% 10 10 25 3.8964 3.9536 3.9534 -0.2 3.9534 57.0 98.28%

Average 56.8 98.00%

Standard Deviation 0.6 1.12%

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Table A4: LFB Low Inorganic Standard TS Stable Weigh Hot Block

Sample # Bag # Volume

(ml)

Initial weight

(g)

Final weight 1

(g)

Final weight 2

(g)

Final weight 3

(g)

Two Consecutive

Weights Difference

(mg)

Final weight used (mg)

Final Solids Recovered

Weight (mg)

Percent Recovery

1 1 25 3.9219 3.9798 3.9794 -0.4 3.9794 57.5 99.14% 2 2 25 3.9052 3.9629 3.9626 -0.3 3.9626 57.4 98.97% 3 3 25 3.9091 3.9668 3.9664 -0.4 3.9664 57.3 98.79% 4 4 25 3.9040 3.9616 3.9612 -0.4 3.9612 57.2 98.62% 5 5 25 3.9139 3.9713 3.9713 0.0 3.9713 57.4 98.97% 6 6 25 3.8814 3.9386 3.9384 -0.2 3.9384 57.0 98.28% 7 7 25 3.9011 3.9589 3.9585 -0.4 3.9585 57.4 98.97% 8 8 25 3.9131 3.9710 3.9708 -0.2 3.9708 57.7 99.48% 9 9 25 3.8918 3.9485 3.9487 0.2 3.9487 56.9 98.10% 10 10 25 3.8914 3.9483 3.9482 -0.1 3.9482 56.8 97.93%

Average 57.3 98.72%

Standard Deviation 0.3 0.49%

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Table A5: LFB Low Inorganic Standard TS Evaporation Dish

Sample #

Dish #

Volume (ml)

Initial weight

(g)

Final weight 1

(g)

Final weight 2

(g)

Final weight 3

(g)

Two Consecutive

Weights Difference

(mg)

Final weight used (mg)

Final Solids Recovered

Weight (mg)

Percent Recovery

1 3 25 80.7460 80.8000 80.8022 80.8017 -0.5 80.8017 55.7 96.03% 2 23 25 92.0546 92.1084 92.1108 92.1106 -0.2 92.1106 56.0 96.55% 3 16 25 70.3770 70.4318 70.4319 0.1 70.4319 54.9 94.66% 4 5 25 80.1832 80.2397 80.2401 0.4 80.2401 56.9 98.10% 5 7 25 77.3485 77.4038 77.4048 77.4045 -0.3 77.4045 56.0 96.55% 6 A 25 83.3934 83.4492 83.4490 -0.2 83.4490 55.6 95.86% 7 13 25 71.7404 71.7981 71.7975 71.7972 -0.3 71.7972 56.8 97.93% 8 18 25 69.7256 69.7826 69.7826 0.0 69.7826 57.0 98.28% 9 20 25 91.8968 91.9542 91.9547 0.5 91.9547 57.9 99.83% 10 1 25 80.0774 80.1351 80.1351 0.0 80.1351 57.7 99.48%

Average 56.5 97.33%

Standard Deviation 1.0 1.66%

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Table A6: LFB High Inorganic Standard TS Stable Weigh Oven

Sample #

Bag #

Volume (ml)

Initial weight

(g)

Final weight 1

(g)

Final weight 2

(g)

Final weight 3

(g)

Two Consecutive

Weights Difference

(mg)

Final weight used

(mg)

Final Solids

Recovered Weight

(mg)

Percent Recovery

1 1 25 3.9114 4.6998 4.6995 -0.3 4.6995 788.1 100.65% 2 2 25 3.8915 4.6771 4.6768 -0.3 4.6768 785.3 100.29% 3 3 25 3.9142 4.6961 4.6958 -0.3 4.6958 781.6 99.82% 4 4 25 3.9286 4.7117 4.7117 0.0 4.7117 783.1 100.01% 5 5 25 3.5072 4.2915 4.2912 -0.3 4.2912 784.0 100.13% 6 6 25 3.5009 4.2860 4.2857 -0.3 4.2857 784.8 100.23% 7 7 25 3.6093 4.3913 4.3911 -0.2 4.3911 781.8 99.85% 8 8 25 3.8950 4.6748 4.6745 -0.3 4.6745 779.5 99.55% 9 9 25 3.9039 4.6843 4.6840 -0.3 4.6840 780.1 99.63% 10 10 25 3.6310 4.4122 4.4118 -0.4 4.4118 780.8 99.72%

Average 782.9 99.99%

Standard Deviation 2.7 0.34%

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Table A7: LFB High Inorganic Standard TS Stable Weigh Hot Block

Sample #

Bag #

Volume (ml)

Initial weight

(g)

Final weight 1

(g)

Final weight 2

(g)

Final weight 3

(g)

Two Consecutive

Weights Difference

(mg)

Final weight used

(mg)

Final Solids

Recovered Weight

(mg)

Percent Recovery

1 1 25 3.9158 4.7038 4.7033 -0.5 4.7038 788.0 100.64% 2 2 25 3.8754 4.6621 4.6619 -0.2 4.6621 786.7 100.47% 3 3 25 3.5794 4.3651 4.3651 0.0 4.3651 785.7 100.34% 4 4 25 3.8957 4.6814 4.6812 -0.2 4.6814 785.7 100.34% 5 5 25 3.6152 4.3965 4.3963 -0.2 4.3965 781.3 99.78% 6 6 25 3.6449 4.4288 4.4285 -0.3 4.4288 783.9 100.11% 7 7 25 3.5953 4.3767 4.3770 0.3 4.3767 781.4 99.80% 8 8 25 3.9047 4.6853 4.6850 -0.3 4.6853 780.6 99.69% 9 9 25 3.6048 4.3836 4.3835 -0.1 4.3836 778.8 99.46% 10 10 25 3.8922 4.6745 4.6742 -0.3 4.6745 782.3 99.91%

Average 783.4 100.06%

Standard Deviation 3.0 0.38%

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Table A8: LFB High Inorganic Standard TS Evaporation Dish

Sample #

Dish #

Volume (ml)

Initial weight

(g)

Final weight 1

(g)

Final weight 2

(g)

Final weight 3

(g)

Two Consecutive

Weights Difference

(mg)

Final weight used

(mg)

Final Solids

Recovered Weight

(mg)

Percent Recovery

1 24 25 94.5861 95.3642 95.3646 0.4 95.3646 778.5 99.43% 2 4 25 80.6523 81.4280 81.4294 81.4295 0.1 81.4295 777.2 99.26% 3 9 25 71.0454 71.8256 71.8261 0.5 71.8261 780.7 99.71% 4 12 25 71.3363 72.1176 72.1185 72.1180 -0.5 72.1180 781.7 99.83% 5 2 25 88.0683 88.8486 88.8500 88.8499 -0.1 88.8499 781.6 99.82% 6 14 25 70.1568 70.9349 70.9366 70.9365 -0.1 70.9365 779.7 99.58% 7 10 25 70.3863 71.1705 71.1707 0.2 71.1707 784.4 100.18% 8 8 25 71.2983 72.0807 72.0812 0.5 72.0812 782.9 99.99% 9 17 25 71.1083 71.8899 71.8902 0.3 71.8902 781.9 99.86% 10 6 25 71.8202 72.5993 72.5998 0.5 72.5998 779.6 99.57%

Average 780.8 99.72%

Standard Deviation 2.1 0.27%

21

Table A9: Biosolids, Drying Oven, Stable Weigh

Sample #

Bag #

Volume (ml)

Initial weight

(g)

Final weight 1

(g)

Final weight 2

(g)

Final weight 3

(g)

Two Consecutive

Weights Difference

(mg)

Final weight used (mg)

Final Solids Recovered

Weight (mg)

1 1 25 3.9184 4.6407 4.6406 -0.1 4.6406 722.2 2 2 25 3.9125 4.6331 4.6328 -0.3 4.6328 720.3 3 3 25 3.9114 4.6252 4.6252 0.0 4.6252 713.8 4 4 25 3.8827 4.5990 4.5987 -0.3 4.5987 716.0 5 5 25 3.8992 4.6250 4.6248 -0.2 4.6248 725.6 6 6 25 3.9333 4.6584 4.6582 -0.2 4.6582 724.9 7 7 25 3.8864 4.6068 4.6068 0.0 4.6068 720.4 8 8 25 3.9001 4.6197 4.6195 -0.2 4.6195 719.4 9 9 25 3.8999 4.6155 4.6159 0.4 4.6159 716.0 10 10 25 3.9105 4.6276 4.6273 -0.3 4.6273 716.8

Average 719.5

Standard Deviation 3.9

22

Table A10: Biosolids, Hot Block, Stable Weigh

Sample #

Bag #

Volume (ml)

Initial weight

(g)

Final weight 1

(g)

Final weight 2

(g)

Final weight 3

(g)

Two Consecutive

Weights Difference

(mg)

Final weight used (mg)

Final Solids Recovered

Weight (mg)

1 11 25 3.8932 4.5998 4.5980 4.5978 -0.2 4.5978 704.6 2 12 25 3.8895 4.6013 4.6008 -0.5 4.6008 711.3 3 13 25 3.8858 4.6064 4.6059 -0.5 4.6059 720.1 4 14 25 3.5462 4.2570 4.2531 4.2534 0.3 4.2534 707.2 5 15 25 3.9051 4.6063 4.6037 4.6036 -0.1 4.6036 698.5 6 16 25 3.8870 4.5899 4.5895 -0.4 4.5895 702.5 7 17 25 3.9082 4.6122 4.6117 -0.5 4.6117 703.5 8 18 25 3.9019 4.5990 4.5987 -0.3 4.5987 696.8 9 19 25 3.9025 4.6013 4.6011 -0.2 4.6011 698.6 10 20 25 3.9094 4.6202 4.6197 -0.5 4.6197 710.3

Average 705.3

Standard Deviation 7.1

23

Table A11: Biosolids, Drying Oven, Evaporation Dish

Sample #

Dish #

Volume (ml)

Initial weight

(g)

Final weight 1

(g)

Final weight 2

(g)

Final weight 3

(g)

Two Consecutive

Weights Difference

(mg)

Final weight used (mg)

Final Solids Recovered

Weight (mg)

1 20 25 91.8975 92.6090 92.6163 92.6167 0.4 92.6167 719.2 2 16 25 70.3774 71.0945 71.1032 71.1034 0.2 71.1034 726.0 3 A 25 83.3937 84.1089 84.1164 84.1169 0.5 84.1169 723.2 4 3 25 80.7467 81.4655 81.4724 81.4721 -0.3 81.4721 725.4 5 5 25 80.1838 80.9014 80.8984 * -3.0 * * 6 7 25 77.3493 78.0623 78.0624 0.1 78.0624 713.1 7 18 25 69.7260 70.4513 70.4464 * -4.9 * * 8 23 25 92.0549 92.7767 92.7743 * -2.4 * * 9 13 25 71.7408 72.4644 72.4641 -0.3 72.4641 723.3 10 1 25 80.0785 80.7966 80.7966 0.0 80.7966 718.1

Average 721.2

Standard Deviation 4.6

* Bag Weight Varies Due to Crusting on Surface

24

Table A12: StableWeigh and Porcelain Evaporation Dish Precision

TS Mass Vessel Average Standard Deviation % RSD Duplicate Relative

Percent Difference

58 mg StableWeigh, Oven 56.8 0.6 1.138% 3.866%

58 mg StableWeigh, Hot Block 57.3 0.3 0.495% 1.572%

58 mg Porcelain Evaporation Dish 56.5 1.0 1.710% 5.319%

783 mg StableWeigh, Oven 782.9 2.7 0.342% 1.097%

783 mg StableWeigh, Hot Block 783.4 3.0 0.00384% 1.174%

783 mg Porcelain Evaporation Dish 780.8 2.1 0.273% 0.922%

Biosolids StableWeigh, Oven 719.5 3.9 0.547% 1.640%

Biosolids StableWeigh, Hot Block 705.3 7.1 1.012% 3.289%

Biosolids Porcelain Evaporation Dish ** ** ** **

**: Biosolids in Evaporation Dish crusted over 30% of the samples and no stable weight difference (0.5 mg or less in two consecutive weighing) was achieved.

25

Table A13: StableWeigh Laboratory Reagent Blank Percent Variance

Sample # 1 2 3 4 5 6 7 8 9 10 Average Standard Deviation

StableWeigh, Oven LRB Weight Difference (%) 0.0154% 0.0335% 0.0050% 0.0027% 0.0162% 0.0108% 0.0108% 0.0000% -0.0054% 0.0218% 0.0111% 0.0114%

StableWeigh, Hot Block LRB Weight Difference (%) 0.0508% 0.0350% 0.0352% 0.0267% 0.0324% 0.0284% 0.0305% 0.0206% 0.0256% 0.0204% 0.0306% 0.0088%

26

Figure 6: LFB IDC Low Inorganic Standard TS Stable Weigh Oven

27

Figure 7: LFB IDC Low Inorganic Standard TS Stable Weigh Hot Block

28

Figure 8: LFB IDC Low Inorganic Standard TS Evaporation Dish

29

Figure 9: LFB IDC High Inorganic Standard TS Stable Weigh Oven

30

Figure 10: LFB IDC High Inorganic Standard TS Stable Weigh Hot Block

31

Figure 11: LFB IDC Low Inorganic Standard TS Evaporation Dish

32

Figure 12: IDC Biosolids, Drying Oven, Stable Weigh

33

Figure 13: IDC Biosolids, Hot Block, Stable Weigh

34

Figure 14: High Inorganic Standard Averages vs. Standard Value