Reference_-_Laboratory_Manual_2022_2f_3.pdf

Operation and Maintenance of Ohmsett Contract E17PC00014

Operating Manual for Ohmsett Laboratory Including Laboratory Procedures

Prepared for:

Bureau of Safety and Environmental Enforcement (BSEE)

Contracting Officer’s Representative (COR) Frank Jurado

BSEE Oil Spill Preparedness Division 45600 Woodland Road

Sterling, VA 20166 Email: Frank.Jurado@bsee.gov

Ph. 571-279-7896

Prepared by:

Applied Research Associates, Inc.

Operating Contractor

Ohmsett Facility

Naval Weapons Station Earle (NWSE) Waterfront Route 36

P.O. Box 150, Leonardo, NJ 07737

Date: September 30, 2022

Operating Manual for Ohmsett Laboratory Including Laboratory Procedures i

TABLE OF CONTENTS

1. REQUIREMENT

2. APPROACH

2.1. PRACTICES

2.1.1. Cooperation and Continuity

2.1.2. Equipment and Supplies

2.1.3. Safety

2.1.4. Lab Waste Disposal

3. LABORATORY DATA QUALITY AND OBJECTIVES

4. TOTAL PETROLEUM HYDROCARBON IN WATER–NON-DISPERSIVE INFRARED

METHOD

4.1. SCOPE AND APPLICATION

4.2. SUMMARY OF METHOD

4.3. INTERFERENCES

4.4. COMMENTS

4.5. DEFINITIONS

4.5.1. Unknown Oil

4.5.2. Known Oil

4.6. APPARATUS

4.7. REAGENTS

4.8. PROCEDURE

4.9. PRECISION AND ACCURACY

4.10. REFERENCES

5. TOTAL PETROLEUM HYDROCARBON IN WATER – FLUOROMETRIC METHOD

5.1. SCOPE AND APPLICATION

5.2. SUMMARY OF METHOD

5.3. COMMENTS

5.4. APPARATUS AND MATERIALS

5.5. GENERAL PROCEDURE

5.6. PRECISION AND ACCURACY

5.7. REFERENCES

ii

6. MEASUREMENT OF POTENTIAL HYDROGEN (PH)

6.1. SCOPE AND APPLICATION

6.2. SUMMARY OF METHOD

6.3. INTERFERENCES

6.4. COMMENTS

6.5. APPARATUS

6.6. SAMPLING AND STORAGE

6.7. CALIBRATION

6.8. PH MEASUREMENT

6.9. CALCULATIONS

6.10. REFERENCES

7. SALINITY/CONDUCTANCE/REFRACTOMETRY

7.1. SCOPE AND APPLICATION

7.2. SUMMARY OF METHOD

7.3. INTERFERENCES

7.4. APPARATUS

7.5. SAMPLING AND STORAGE

7.6. PROCEDURE FOR SALINITY – CONDUCTIVITY METER

7.7. PROCEDURE FOR CONDUCTIVITY

7.8. PROCEDURE FOR SALINITY – REFRACTOMETER

7.9. CALCULATION

7.10. REFERENCES

8. SPECIFIC GRAVITY – HYDROMETER METHOD

8.1. SCOPE AND APPLICATION

8.2. SUMMARY OF METHOD

8.3. COMMENTS

8.4. DEFINITIONS

8.4.1. Density

8.4.2. Specific Gravity

8.4.3. API Gravity

8.4.4. Observed Values

iii

8.5. APPARATUS

8.5.1. Hydrometers

8.5.2. Thermometers

8.5.3. Hydrometer Cylinder

8.5.4. Constant Temperature Bath

8.6. PROCEDURE

8.7. CALCULATIONS AND REPORT

8.8. PRECISION AND ACCURACY

8.9. REFERENCES

9. DENSITY – INSTRUMENTAL METHOD (ULTRASONIC)

9.1. SCOPE OF APPLICATION

9.2. COMMENTS

9.3. DEFINITIONS

9.3.1. Density

9.3.2. Specific Gravity

9.3.3. API Gravity

9.4. APPARATUS

9.5. CALIBRATION

9.6. MEASUREMENT

9.7. ACCURACY

9.8. REFERENCES

10. SURFACE AND INTERFACIAL TENSION

10.1. SCOPE AND APPLICATION

10.2. SUMMARY OF METHOD

10.3. APPARATUS

10.3.1. Tensiometer

10.3.2. Platinum Wire Ring

10.3.3. Sample Container

10.4. SAMPLING AND STORAGE

10.5. CALIBRATION

10.6. CALIBRATION CORRECTION

iv

10.7. PROCEDURE

10.8. CALCULATIONS

10.9. PRECISION AND ACCURACY

10.10. REFERENCES

11. WATER AND SEDIMENT IN PETROLEUM – CENTRIFUGE (BOTTOM SOLIDS AND

WATER)

11.1. SCOPE AND APPLICATION

11.2. SUMMARY OF METHOD

11.3. APPARATUS

11.3.1. Centrifuge

11.3.2. Centrifuge Tubes

11.4. REAGENTS

11.5. SAMPLING AND STORAGE

11.6. PROCEDURE

11.7. CALCULATIONS

11.8. PRECISION AND ACCURACY

11.9. REFERENCES

12. TEMPERATURE

12.1. SCOPE AND APPLICATION

12.2. SUMMARY OF METHOD

12.3. INTERFERENCES

12.4. DEFINITIONS

12.5. APPARATUS

12.5.1. Thermometers

12.5.2. Electronic Traceable Thermometer/Thermistors

12.6. SAMPLING AND STORAGE

12.7. PROCEDURE

12.8. CALCULATIONS

12.9. PRECISION AND ACCURACY

12.10. REFERENCES

13. TURBIDITY

v

13.1. SCOPE AND APPLICATION

13.2. SUMMARY OF METHOD

13.3. INTERFERENCES

13.4. APPARATUS

13.5. COMMENTS

13.6. CALIBRATION

13.7. PROCEDURE

13.8. PRECISION AND ACCURACY

13.9. REFERENCES

14. VISCOSITY

14.1. SCOPE AND APPLICATION

14.2. SUMMARY OF METHOD

14.3. COMMENTS

14.4. APPARATUS

14.4.1. Spindles

14.4.2. Thermoregulator

14.4.3. Viscometer

14.5. REAGENTS

14.6. PREPARATION AND CALIBRATION

14.7. PROCEDURE

14.8. CALCULATIONS

14.9. PRECISION AND ACCURACY

14.10. REFERENCES

15. SPECIFIC GRAVITY OF VISCOUS FLUIDS – PYCNOMETER METHOD

15.1. SCOPE AND APPLICATION

15.2. COMMENTS

15.3. APPARATUS

15.4. PROCEDURE

15.5. PRECISION AND ACCURACY

15.6. REFERENCES

16. MYRON ULTRAMETER II 6PFC

vi

16.1. SCOPE AND APPLICATION

16.2. ACCURACY AND RESOLUTION

16.3. PROCEDURE

16.4. CALIBRATION

16.5. MAINTENANCE

16.6. REFERENCES

Appendix A. LIST OF CONVERSIONS

LIST OF TABLES

Table 1. Calibration Correction Table

Operation and Maintenance of Ohmsett Contract E17PC00014

Operating Manual for Ohmsett Laboratory Including Laboratory Procedures

1. REQUIREMENT

Contract E17PC00014 Task Order E17PD00117 Section 2.4.1.12. Operating manuals detail required routine activities and are to be used as references by the Contractor in operating the systems described.

These manuals also guide the routine operations and maintenance of the facility. The Contractor shall update the following manuals as needed when major changes occur.

2. APPROACH

The purpose of this manual is to outline, specify, and detail the laboratory facilities and analytical techniques available at the Ohmsett Facility Laboratory. The laboratory is equipped to perform routine sampling, analysis and data reporting on test basin and bay water and test oils as per the procedures which follow. Non-routine testing is available within the scope of the laboratory equipment upon direction of appropriate ARA or client personnel.

2.1. PRACTICES

2.1.1. Cooperation and Continuity

Without complete cooperation, an analysis may be needlessly duplicated, erroneously performed, or eliminated entirely; therefore, all personnel in the laboratory are responsible for completion of samples assigned to them from the procedures requested to the finished data and report. In order that all sources of error may be minimized, any specific analysis begun by a person shall be completed entirely by that person. If it is impossible for the person to complete a procedure, he/she shall outline the portion of the analysis completed and detail the remaining requirements before allowing another person to continue the analysis. A complete analytical procedure includes the following.

• Understanding of the analysis to be performed and where immediate attention is required to obtain valid results

• Setting up and performing these analyses in an orderly progression to achieve optimum results

• Recording of raw data and reporting of final data as directed

• Securing, operating, and storing of equipment employed

• Returning of reagents to storage

• Full responsibility for cleaning equipment, glassware, and working area to reduce danger to fellow workers

These duties may be performed as a joint effort, provided all personnel know their tasks, and a concise line of communication is maintained.

2.1.2. Equipment and Supplies

Instrumentation: The operation of laboratory equipment is a comprehensive job description. Extensive damage may result from improper use. READ AND FOLLOW THE INSTRUCTIONS IN THE OPERATION MANUALS. Complete operational and maintenance manuals are available in the maintenance files.

Personnel shall be trained in the use of an instrument before they can operate or tamper with the instrument. Damage to an instrument shall be reported immediately.

Reagents and General Supplies: An inventory is kept of all reagents and chemicals in stock. This inventory shall be reviewed semi-annually or more often as necessary. Replacements should be ordered when needed or as per expiration specifications.

2.1.3. Safety

It is the responsibility for all laboratory personnel (including outside contractors using laboratory facilities) to read and observe the Ohmsett Health & Safety Plan sections applicable to the laboratory.

The laboratory is equipped for the tests described in this manual and laboratory personnel must know the requirements of each procedure before working in the laboratory unsupervised. Approved protective eyewear shall always be worn by any personnel in the laboratory.

There are several potentially dangerous chemicals in use and in storage that must be maintained in their proper place and containers. One should never mix chemicals without a thorough knowledge of the possible reactions and reaction products that may result. The laboratory is equipped with two fume hoods with pull-down splash shields or hood sashes, which must be used when working with volatile, hazardous, or toxic chemicals. Open containers of materials that produce corrosive or poisonous fumes will not be permitted. Any chemicals that are transferred to containers other than originally supplied must be properly labeled.

Clean sinks and counters are very important to the safety of employees and visitors as well as environmental compliance. Chemicals should never be disposed of in a sink unless that method is recommended by the procedure and the chemical is neutralized and adequately flushed away.

Informative signs are placed in areas of possible danger. The appropriate facilities and services that are available should be used for the disposal of liquid or dry chemicals and broken glass.

All laboratory personnel shall be familiar with the distribution, location, and operation of safety equipment provided: fire extinguishers, safety showers, eye wash basins, fire blankets, safety glasses, aprons, thermal, rubber, or plastic gloves, and the use of resuscitators, and air masks.

Flammable and hazardous liquids shall be stored in the flammable storage cabinet beneath the fume hood, or in bulk storage in the flammable cabinets outside in the designated area. All flammable liquids, and corrosive or caustic materials shall be so labeled.

Except for expensive, repairable ground glass pieces, all chipped glassware will be discarded. Wear protective gloves and safety glasses whenever handling broken or damaged glassware.

Depending on the application, plastic bottles shall be either washed in a 1:10 aqueous solution of hydrochloric acid (HCl) and rinsed well with distilled water; or shall have two toluene rinses with an acetone rinse, and final rinse with distilled water.

2.1.4. Lab Waste Disposal

Generation: There are four types of waste produced by routine testing and cleaning procedures conducted at Ohmsett. They are:

• Non-chlorinated organic liquids and solvents o Refined oils o Fuel oils o Crude oils o Toluene o Acetone o Alcohols o Ethylene glycol o Acetonitrile o Hexane o Heptane o 2,2,4-Trimethylpentane o Hexadecane

• Chlorinated solvents o Methylene Chloride o 1,2-Dichloroethane o Chlorobenzene o Horiba S-316 (chlorotrifluoroethylene/polychlorotrifluoroethylene)

• Acids o Sulfuric o Phosphoric o Nitric o Hydrochloric o Acetic

• Bases o Sodium hydroxide o Ammonium hydroxide o Sodium Bicarbonate

The largest quantities of hazardous waste are the lubricating oils and crude oils used during tank testing of oil spill equipment. Thousands of gallons of used oils have been generated through the years. The lab generated waste has been approximately 50 gallons per year.

Control: Test oil samples are received, stored, dispersed, refurbished, and disposed of under the control of the laboratory technician and test engineer/scientist. The laboratory wastes are also monitored by the lab technician and test engineer/scientist.

Hazardous material received by the lab is recorded in the purchase order file. Hazardous waste solvents are collected in five-gallon carboy containers. These containers (one for non-chlorinated and one for chlorinated wastes) are kept in a proper storage area outside of the lab when not in use in the lab. The waste is transferred to one of three specially designed and marked, flammable waste cabinets located in Resource Conservation and Recovery Act (RCRA) qualifying containment outside of Building R24. A monthly inspection is made of the waste cabinet. The inspection is recorded. Any problems are verbally reported to the Program Manager.

Disposal: The acid and bases in the Ohmsett laboratory should be disposed of in properly labeled NWS Earle waste containers. s. Do not attempt neutralization by mixing acids and bases. The lab sinks drain through the sewer system to the local Public Owned Treatment Works (POTW) through a backup neutralization and sediment trap outside the laboratory. Materials disposed in this way comprise a very small quantity of waste produced by the laboratory, or less than three gallons/month over the last five years. Hazardous Waste is removed from the facility by the NWS Earle Environmental Division in accordance with Hazardous Waste Management Plan WPNSTAE Earle Instruction 5090.1A.

3. LABORATORY DATA QUALITY AND OBJECTIVES

MEASUREMEN

T TEST INSTRUMENT(S) PRECISION ACCURACY CAL.

STANDARD

Oil in Water

Oil Content in Water (Solv Extr, NDIR)

Horiba OCMA-500 Oil Content Analyzer, Extraction Sep.

Funnel, 0 - 9.9 mg/L ± 0.2 mg/L

10.0 - 99.9 mg/L ± 2.0mg/L 100 to 200 mg/L:

±4.0mg/L

±0.01 mg/L

Method: Solvent extracts of blanks and "Spiked" dispersions of the test oil in tank water at:

Instr: Prep of the test oil in

S-316 Solv at: 0, 10, 100, 500 mg/l.

Water in Oil

Water and Sediment in Petroleum (Centrifuge)

Centrifuge with relative centrifugal force equal to 500 at the fluid surface and 800 at the bottom.

100 ml Centrifuge tubes, graduated.

Repeatability is dependent on the % water and sediment.

At 7% water in oil:

duplicate results by the same operator should be considered suspect if the standard deviation is greater than 0.4% water in oil.

There is no data available at present to determine accuracy.

Test oil with 1, 5, and 10% tank water blended in at high shear.

Surface Tension & Interfacial Tension

Interfacial Tension of Oil Against Water by the Ring Method

Fisher Tensiometer

Platinum Ring

Repeatability: Same operator and apparatus,

1.5 % of mean

Reproducibility:

Different operators and apparatus, 5% of mean

± 1.5%

Distilled water

Toluene

NBS Class S fractional weights

Viscosity Viscosity using rotary spindle method as function of temp or shear.

Haake VT550 pH Solution proton activity

Thermo Sci, Orion 3 Star pH/mV meter

0.4 % of full scale

± .0.002 RA

Specific Gravity and Density

Hydrometer Method

Set of hydrometers

Thermometer

Repeatability: Duplicate results by the same operator should be considered suspect if

± 0.001 g/ml

Std. reference solutions as available through

MEASUREMEN

T TEST INSTRUMENT(S) PRECISION ACCURACY CAL.

STANDARD

Densitometer

Pycnometer

Mettler Toledo

Densito 30PX Densitometer

Pycnometer, Thermometer the results differ by more than 2 %.

± 0.01 % at cont. T

± 2 % of mean value lab supply sources.

Salinity Refractometry

Conductivity

Handheld refractometer

YSI Handheld Conductivity/Salinity Meter

± 7 % of mean value

± 2 % of full scale

± 10 % in 20 to 40 ppt range

± 0.1 ppt

1,000,10,000,100 ,000µS/cm YSI Calibrators

Turbidity Measurement of turbidity resulting from suspended matter

Oakton EUTECH T-

±0.1 NTU or ±1% of read

± 2% 0-500 NTU

Manufacturer

± 3% 501-1000

NTU

800,100,20,0.02 NTU Oakton calibrators

ORP/Free Cl2 Measurement of oxidation and reduction potential

Myron Ultrameter II ±1 mV

0.01 ppm

±1 mV < 1 ppm

± 0.5 ppm ≥ 1 ppm

± 0.2 ppm pH 7.01 Standard

TDS Measurement of Total Dissolved Solids

Myron Ultrameter II 0.01 (<100 ppm)

0.1 (<1000 ppm)

1.0 (<10 ppt)

0.01 (<100 ppt)

0.1 (<200 ppt)

± 1% of reading NIST TDS Standards 3740 ppm 7860 ppm, 2027 ppm/NaCl

4. TOTAL PETROLEUM HYDROCARBON IN WATER–NON-DISPERSIVE INFRARED

METHOD

4.1. SCOPE AND APPLICATION

The total petroleum hydrocarbon (TPHC) in water–non-dispersive infrared (NDIR) method includes the measurement of solvent extractable hydrocarbons from fresh and saline waters, as well as industrial and domestic aqueous wastes. The method is applicable for measurement of most heavy, intermediate, and light petroleum hydrocarbons, although loss of a significant amount of any gasoline, or other highly volatile petroleum component, that may be present during the extraction can be expected.

The methodology and instrumentation used in this determination have been designed to meet the requirements of EPA Test Method 418.1, Petroleum Hydrocarbons (Spectrophotometric, Infrared).

This method covers the range for 0.2 to 1000 mg/l of extractable material.

4.2. SUMMARY OF METHOD

The sample is subjected to solvent extraction using the standard S-316 solvent (polymerized chlorotrifluoroethylene) with subsequent non-dispersive infrared (NDIR) analysis using the Horiba OCMA- 500 Oil Content Analyzer. Extract analysis is in the 2941 to 2857 cm-1 (3.4 to 3.5 μm) or near IR wavelength region. Samples with oils of known specific gravity higher than 0.895 utilize the B-Heavy Oil accessory to determine the TPHC concentration by this method.

4.3. INTERFERENCES

The OCMA-500 automatically judges the stability of the measurement value from the time the liquid is transferred to the measurement cell until the measurement results are displayed. This function eliminates measurement errors due to individual variations. To judge the stability, the moving average for 10 seconds is used. The final value is displayed when the moving average is less than 0.1 mg/L for 10 seconds. The stability function takes approximately 20 seconds total.

The definition of grease and oil is based on the procedure used. The source of the oil and/or grease and the presence of extractable non-oily matter will influence the measurement and interpretation of results.

4.4. COMMENTS

The minimum concentration of five mg/l for quantifying oils with unknown identity is derived from an EPA method for Oil and Grease. Difficult-to-handle emulsions may form when oil in water concentrations exceed the method's concentration limit (1000 mg/l).

4.5. DEFINITIONS

4.5.1. Unknown Oil

Defined as one for which a representative sample of the oil or grease is not available for preparation of a standard. Examples of unknown oils are the oil and grease in a mixed sewerage or an unidentified oil slick on surface water.

4.5.2. Known Oil

Defined as a sample of oil and/or grease that represents the only material of that type used or manufactured in the processes represented by a wastewater.

4.6. APPARATUS

• Separatory funnel, 2000 ml, with Teflon stopcock

• Horiba OCMA-500 NDIR analyzer

• Sample cells

• 10 ml and 15 ml volumetric pipettes

• 100 ml and 250 ml measuring flasks

• No. 40 Whatman filter paper

4.7. REAGENTS

• S316 Solvent: standard polymerized chlorotrifluoroethylene

• 2,2,4-Trimethylpentane (isooctane)

• Hexadecane (Cetane)

• Chlorobenzene (mono)

• Hydrochloric Acid (1 M)

4.8. PROCEDURE

Step Procedure 1 Collect a representative water sample in a 1-liter glass bottle with Teflon lined inner lid.

2 Add hydrochloric acid to bring the pH to ≤ 2.

3 Perform calibration, zero, span, and measurement of zero solvent in terms of milligrams per liter (Ref. 3.2 Calibration, Horiba Manual) 4 Select mg/L on the OCMA-500 for oil in water analysis.

5 Shake the glass sample bottle to assure good mixing of sample. Accurately pipette 10 ml into a

40 ml vial. The sample volume may be varied, and a dilution factor applied to the results to measure a broad range from lower or higher concentration samples.

6 Accurately pipette 10 ml of solvent into the 40 ml vial. The solvent volume may be varied, and a dilution factor applied to the results to measure a broad range from lower or higher concentration samples.

7 Cap the vial and shake it vigorously to extract oil in water to oil in solvent. (Note: an inline reciprocal shaker can facilitate the processing in excess of 40 samples simultaneously.)

8 Place the vial in an upright position and allow the air bubbles to come out of the solvent;

normally less than 30 seconds

9 Carefully view the vial. There should be an abrupt break between the solvent on the bottom and the water on the top. There should not be any emulsion layer. The solvent/extract may be colored for some samples but should not be unduly turbid.

Step Procedure Note: If required, treat the extract to break an emulsion as follows. If not required, proceed to Step 10.

• Pipette as much solvent/extract as possible without taking the water layer into a clean beaker.

• Add one or more grams of anhydrous sodium sulfate to break the emulsion by stirring with a glass rod. The extract should appear non-turbid but may be colored for some samples.

• Put a conditioned 11 cm No. 40 Whatman filter paper into a glass funnel and filter the extract to remove sodium sulfate ppt.

• If less than 6 ml of sample/extract are recovered, add a measured amount of solvent, and account for the dilution in the results.

10 Pipette about 6 ml of solvent/extract to fill the OCMA-500 cell.

11 Place the cell into the OCMA-500 for measurement.

12 Read the concentration or press MEASURE to start the stability check. Be sure to account for any dilution/concentration when using a water solvent ration other than 1:1 or when solvent is added in Step 9. Readings are in terms of Total Recoverable Oil and Grease.

13 If a measurement of TPHC is needed, the extract may be treated with conditioned silica gel, filtered with a No. 40 Whatman filter paper, and measured. The difference Oil and Grease minus TPHC is the non-petroleum hydrocarbons.

14 Remove the cell from the OCMA-500 and empty the cell in preparation for the next measurement.

Note: A second reading of the same extract may be taken to confirm the accuracy, or the operator may rinse the cell with a small amount of extract prior to making a measurement. It is not necessary to re-zero after every sample. EPA recommends calibration every 10 samples.

4.9. PRECISION AND ACCURACY

Based on the ASTM survey of this method, a single laboratory determined the oil and grease level in sewerage to be 17.5 mg/l. When one-liter portions of the sewerage were dosed with 14.0 mg of a mixture of #2 fuel and Wesson oil, the recovery was 99% with a standard deviation of 1.4 mg. Figures are converted to percentages in Section 2.

4.10. REFERENCES

1. EPA Test Method 418.1, Petroleum Hydrocarbons (Spectrophotometric, Infrared), 1978.

2. Horiba Oil Content Analyzer OCMA-350 Manual, Code: I042118100, Horiba Ltd., 1995.

3. Gruenfeld, M., Extraction of Dispersed Oils from Water for Quantitative Analysis by Infrared

Spectroscopy, Environ. Sc. Technology 7,636, 1973.

5. TOTAL PETROLEUM HYDROCARBON IN WATER – FLUOROMETRIC METHOD

5.1. SCOPE AND APPLICATION

The TPHC in water – fluorometric method includes the measurement of solvent extractable hydrocarbons from fresh and saline waters, as well as industrial and domestic aqueous wastes. The method is applicable for measurement of most heavy, intermediate, and light petroleum hydrocarbons, although loss of a significant amount of any highly volatile petroleum component present during the extraction can be expected.

The methodology and instrumentation used in this determination have been designed to meet the requirements of EPA Test Method 1664 as an excepted fast procedure for the field.

This method covers the range for 0.2 to 1000 mg/l of extractable material.

5.2. SUMMARY OF METHOD

This procedure describes the extraction of sample water with hexane (or similar alkane). The extraction volumes for the water and hexane can be changed to customize the procedure for specific performance needs. Extracted samples are read using a laboratory fluorometer. Standard concentration curves must be developed using extract standards of known hydrocarbon concentration.

5.3. COMMENTS

The presence of fluorescing biological compounds will interfere with the determination of petroleum hydrocarbons. Measures must be taken to either selectively remove other interfering fluorescing compounds or normalizing the determination to the known presence of these compounds.

The method must be normalized to the oil or combination of oils present, especially in the case of crude oils. Different crude oils contain varying amounts of native fluorescing compounds. Additionally, this method should not be employed to analyze for oils that contain either little or no fluorescing compounds.

Oils that would not be candidate for this method include straight chain and minimally branching aliphatic and paraffinic.

Analytical results will vary with the targeted hydrocarbons, chemical background, matrix stability, purity of solvents used for extraction, and care in performing the analysis.

5.4. APPARATUS AND MATERIALS

• Turner Designs TD-3100 laboratory fluorimeter

• 10 mm quartz cuvettes

• “Black Oil” optical cylinder and filter kit

• Spectroscopic grade normal hexane

• 6 N hydrochloric acid

• Volumetric flasks, graduated cylinders, and associated laboratory glassware

5.5. GENERAL PROCEDURE

The TD-3100 can be calibrated with a pure standard that is prepared by dissolving a hydrocarbon in hexane. The hydrocarbon in hexane standard is prepared to a concentration that is approximately equivalent to a 25-ppm water sample that is extracted with pure hexane.

Since this method extracts 100 ml of water into 10 ml of hexane, the extract will be ten times the water concentration or 250 ppm. Hence, the working standard used to calibrate the TD-3100 is 250 ppm. Note that the TD-3100 can be calibrated at concentrations other than 25 ppm.

The linearity and sensitivity of this calibration should be checked as described in Appendix 1 of the TD- 3100 Laboratory Fluorometer Operating Manual. The linearity and sensitivity checks may suggest that the calibration solution concentration, the cuvette type, the extraction ratio, or the optical filters and lamb must be changed to suit the application.

First Step — Prepare a 1000 ppm Hydrocarbon Stock Standard

Step Procedure 1 Pipette 100 µl of crude oil into a 100 ml volumetric flask that is approximately half full of hexane.

2 Cap and shake the 100 ml volumetric flask to dissolve the hydrocarbon.

3 Fill the 100 ml volumetric flask with hexane to the 100 ml mark.

4 Cap and shake the 100 ml volumetric flask.

Second Step — Prepare the 225 ppm Calibration Standard

Step Procedure 1 Pipette 25 ml of the 1000 ppm hydrocarbon stock standard into a 100 ml volumetric flask that is approximately half full of hexane.

2 Cap and shake the 100 ml volumetric flask.

3 Fill the 100 ml volumetric flask with hexane to the 100 ml mark.

4 Cap and shake the 100 ml volumetric flask.

Third Step — Calibrate the TD-3100

Step Procedure 1 From the HOME screen, press <ENT>.

2 Press <1>.

3 Press <1> again.

4 Toggle the Mode selection to Multi-Option using the < ↔ > key.

5 Press <ESC>.

6 Press <2>.

7 Toggle the Cal Procedure selection to Direct Conc. Using the < ↔ > key.

8 Press <ESC>.

9 Press <3>.

10 Toggle the Concentration Units to ppm.

11 Press <ESC> two times.

12 Press <2> to start the calibration procedure.

13 If the Max Range (maximum measurement range concentration) is 50.0, press <1> and then proceed to the next step. If the Max Range value is different from 50.0, press <9>, then input 50 and press <ENT>. Now press <1> to continue.

14 Set the number of standards to 1 by pressing <1> followed by <ENT>.

15 If the Std Conc (standard concentration) is 25.0, press <1> and then proceed to the next step.

If the Std Conc is different from 25.0, press <9>, then input 25 and press <ENT>. Now press <1> to continue.

16 Fill a clean cuvette 3/4 full of the 250-ppm hydrocarbon in hexane standard solution. Wipe the outside of the cuvette with a tissue or clean cloth to remove any dirt of oil from handling.

17 Insert the cuvette into the cuvette holder and then insert the cuvette holder into the TD-3100.

Close the lid.

18 Press <*> and wait until the sensitivity has been set.

19 Remove the cuvette holder and the cuvette. Discard the calibration solution.

20 Rinse the cuvette several times with unused hexane, if using not disposable cuvettes.

21 Fill the cuvette 3/4 full of unused hexane. Wipe the outside of the cuvette with a tissue or clean tissue or cloth to remove any dirt or oil from handling 22 Insert the cuvette into the cuvette holder and then insert the cuvette holder into the TD-3100.

Close the lid.

23 Press <ENT>.

24 When the reading is stable, press <0>.

Fourth Step — Extraction and Analysis

The calibration must be checked with either the solid standard or a calibration solution prior to each measurement. If the TD-3100 measurement is outside of the measurement tolerance, recalibrate the TD- 3100 prior to analyzing a sample.

Step Procedure 1 Collect 100 ml of produced water into a clean graduated cylinder or sampling bottle.

2 Adjust the produced water to pH<2 with 6 N hydrochloric acid. Check the pH with disposable pH paper.

3 Add 10 ml of hexane and cap the graduated cylinder or sample bottle.

4 Extract oil from the water by vigorously shaking the graduated cylinder or sample bottle for 2 minutes.

5 Allow hexane to separate from water for approximately 1 minute.

6 The hexane extract is the top layer in the graduated cylinder or sample bottle.

7 Fill a cuvette 3/4 full of the hexane extract. Wipe the outside of the cuvette with a clean tissue or cloth to remove any dirt or oil from handling.

8 Insert the cuvette into the TD-3100, then press <*>. When END is displayed, note the reading.

9 Compare the TD-3100 reading to the look-up table or curve, if used, and record the concentration in ppm.

10 Properly discard the produced water and remaining hexane solvent in accordance with company procedures.

11 Clean the graduated cylinder or sample bottle.

12 Rinse the cuvette several times with clean hexane.

5.6. PRECISION AND ACCURACY

This method was validated through single laboratory studies and an inter-laboratory method validation study (EPA-821-R-98-002; February 1999). Combined data from these studies show an average recovery of 93 percent for hexane extractable materials and 89 percent for non-polar hexane extractable material;

and precision (as relative standard deviation) of 8.7 percent for hexane extractable material and 13 percent for non-polar hexane extractable material.

The method detection limit (MDL) and minimum level of quantitation (ML) are based on five studies conducted by EPA and described at proposal of Method 1664 (61 FR 1730) and as verified by data submitted in comments on the proposal of Method 1664 (Reference 16.3).

5.7. REFERENCES

1. EPA-821-R-98-002; Method 1664, Revision A: N-Hexane Extractable Material (HEM; Oil and Grease) and Silica Gel Treated N-Hexane Extractable Material (SGT-HEM; Non-polar Material) by Extraction and Gravimetry, February 1999.

2. Turner Designs, Doc. 998-0366; The FastHEX™ Method Procedure, TD3100 Version, March 2, 2001.

6. MEASUREMENT OF POTENTIAL HYDROGEN (PH)

6.1. SCOPE AND APPLICATION

This method is applicable to potable waters, surface waters, domestic and industrial sewerage, and saline waters.

6.2. SUMMARY OF METHOD

The pH of a sample is an electro-metric measurement using a combination electrode, either glass and reference, or a solid-state triode.

6.3. INTERFERENCES

Oils and greases, by coating the electrodes, may interfere by causing sluggish response. Also, acidic compounds of fluorine may etch the surface of glass and some ceramic based electrode systems.

6.4. COMMENTS

At least three buffer solutions must be used to initially standardize the instrument. They should cover the range of pH of the samples to be measured. Field pH measurements using comparable instruments are reliable.

6.5. APPARATUS

• Orion 3-Star Plus pH Meter

• Orion #9107BNMD epoxy pH/ATC triode combination electrode

• pH Buffers - Buffers for pH of 4.00, 7.00, and 10.00

6.6. SAMPLING AND STORAGE

The sample must be analyzed as soon as practical, preferably within a few hours. Do not open sample bottle before analysis.

6.7. CALIBRATION

(Note: pH meter should be in standby mode when electrodes are not in fluid.)

Step Procedure 1 Press the POWER key to turn on the meter.

2 Select two buffers that bracket the expected sample pH and are one to four pH units apart.

See the Automatic Buffer Recognition Selection section for the buffer sets that are automatically recognized by the meter.

3 In the measurement mode, press the LINE SELECT key until the icon points to the top line and press the UP-arrow key until the pH icon is shown. Press the CALIBRATE key to begin the calibration.

4 Rinse the electrode (and ATC probe and stirrer probe, if in use) with distilled water and blot dry with a lint free tissue.

5 Insert the electrode into the first buffer and gently stir. If the stirrer probe is in use, press the STIR key to start and stop stirring (bench-top models only).

6 Wait for the pH icon to stop flashing and the icon to start flashing. The meter should display the temperature-corrected pH buffer value. If the displayed buffer value is incorrect or a custom buffer is being used, press the DIGIT key until the first digit to be changed is flashing, press the up/down arrow keys to change the value of the flashing digit and continue to change the digits until the meter displays the temperature-corrected pH buffer value. Once the buffer value is set, press the DIGIT key until the decimal point is in the correct location.

7 Press the CALIBRATE key to proceed to the next calibration point.

8 Rinse the electrode (and ATC probe and stirrer probe, if in use) with distilled water and blot dry with a lint-free tissue.

9 Insert the electrode into the second buffer and gently stir. If the stirrer probe is in use, press the STIR key to start and stop stirring (bench-top models only).

10 Wait for the pH icon to stop flashing and the icon to start flashing. The meter should display the temperature-corrected pH buffer value.

11 Press the MEASURE key to save and end the calibration. The slope will be displayed, and the meter will proceed to the measurement mode.

6.8. PH MEASUREMENT

Turn on the automatic data log feature to send measurements to the meter data log or connect the meter to a printer or computer.

Step Procedure 1 Rinse the electrode (and ATC probe and stirrer probe, if in use) with distilled water and blot dry with a lint-free tissue.

2 If the meter is in the AUTO-READ mode, press the measure key to start a reading. Once the reading is stable, the AR icon will stop flashing and the display will freeze. Press the measure key to take a new measurement. If the stirrer probe is in use, it will start stirring when the measure key is pressed and stop stirring when the AR icon stops flashing (bench-top meters only). If the meter is in the continuous or timed mode, the meter will immediately start taking readings and continuously update the display. Once the reading is stable, the pH icon will stop flashing. If the stirrer probe is in use, press the stir key to start and stop stirring (bench-top meters only).

3 Remove the electrode (and ATC probe and stirrer probe, if in use) from the sample, rinse with distilled water, blot dry with a lint-free tissue, insert into the next sample and repeat Step 2 or see the electrode user guide for recommended storage.

6.9. CALCULATIONS

Report the average of the three readings.

6.10. REFERENCES

1. Methods for Chemical Analysis of Water and Wastes, U.S. EPA, 1971, pp. 230-231.

2. Standard Methods for the Examination of Water and Wastewater, APHA, AWWA, and WPCF; 13th Edition, 1971, p. 267, Method 144A.

3. ASTM Standards, Part 23, Water; Atmospheric Analysis, Method D1293-65, 1970, p. 280.

4. Thermo Scientific, Orion 3-Star pH Meter Manual, #257308-001 Rev A 7-08.

7. SALINITY/CONDUCTANCE/REFRACTOMETRY

7.1. SCOPE AND APPLICATION

This method is applicable to waters containing 0–40 parts per thousand (ppt) salinity.

7.2. SUMMARY OF METHOD

Salinity is calculated by the instrument using measurements of fluid conductivity and temperature. An alternate method to determine salinity is by use of a salinity refractometer.

7.3. INTERFERENCES

Floating hydrocarbons and high concentrations of dissolved hydrocarbons cause interference by coating the probe.

7.4. APPARATUS

YSI Model 30 Salinity Conductivity/Temperature meter or Atago 2442 salinity refractometer.

7.5. SAMPLING AND STORAGE

Measurements may be taken in the laboratory or in situ as the instrument is portable and has a cable-mounted sensor.

7.6. PROCEDURE FOR SALINITY – CONDUCTIVITY METER

Step Procedure 1 Adjust meter to zero by measuring salinity and/or conductivity in DI water at 20°C.

2 Calibrate to a conductivity point using a commercially available (YSI, Cole-Parmer, etc.)

conductivity standard solution at 20°C. For the workable range of salinity at Ohmsett, the conductivity standard(s) may be from 15 to 35 ppt.

3 Immerse probe in sample with instrument in salinity mode and read salinity in ppt directly. Read temperature indicated in the upper right-hand corner of the screen directly in degrees Celsius.

4 Rinse probe with DI water after each determination. Store instrument and probe dry.

7.7. PROCEDURE FOR CONDUCTIVITY

Repeat the procedure for Salinity (6.6 above) with the instrument in the conductivity mode. Report conductivity in mho.

7.8. PROCEDURE FOR SALINITY – REFRACTOMETER

Step Procedure 1 Place one or two 0.005–0.01 ml drops of DI water at 20°C on the sample prism under the daylight plate. Close the daylight plate to evenly spread the DI water.

2 Turn the zero-adjustment screw to indicate zero percent, when viewing through the refractometer, as necessary.

3 Place one or two 0.005–0.01 ml drops of subject water sample at 20°C on the sample prism under the daylight plate. Close the daylight plate to evenly spread the water sample.

4 Read the salinity directly off the scale by viewing through the refractometer. The value is indicated by the interception of the boundary line with the scale.

5 Clean the prism with DI water and a soft, optical rated tissue.

7.9. CALCULATION

No calculations are necessary as the readings are taken directly from the meter.

7.10. REFERENCES

1. Operating Manual for the YSI Model 30S-C-T Meter.

2. Operating Manual #2442-W08 for the Atago 2442 Refractometer.

8. SPECIFIC GRAVITY – HYDROMETER METHOD

8.1. SCOPE AND APPLICATION

This method covers the laboratory determination, using a glass hydrometer, of the density, specific gravity, or API gravity of crude petroleum and non-petroleum products normally handled as liquids, and having a Reid vapor pressure (ASTM Method D323, Test for Vapor Pressure of Petroleum Products [Reid Method]) of 26 pounds or less. Values are measured on a hydrometer at convenient temperatures, readings of density being reduced to 15°C, and readings of specific gravity and API gravity to 60°F, by means of the Petroleum Measurement Tables. Values determined in any one of the three systems of measurements are convertible to equivalent values in either of the other two so that measurements may be made in the units of local convenience.

The hydrometer method is most suitable for determining the density, specific gravity, or API gravity of mobile, transparent liquids. It can also be used for viscous oils by allowing enough time for the hydrometer to reach equilibrium, or for opaque oils by employing a suitable meniscus correction.

When used in connection with bulk oil measurements, volume correction errors are minimized by observing the hydrometer reading at a temperature close to that of the bulk oil temperature.

8.2. SUMMARY OF METHOD

The sample is brought to the prescribed temperature and transferred to a cylinder at approximately the same temperature. The appropriate hydrometer is lowered into the sample and allowed to settle. After temperature equilibrium has been reached, the hydrometer scale is read, and the temperature of the sample is noted. If necessary, the cylinder and its contents are placed in a constant-temperature bath to avoid excessive temperature variation during the test

8.3. COMMENTS

The density, specific gravity, or API gravity by the hydrometer method is most accurate at or near the reference temperature of 15°C or 60°F.

When the hydrometer value is to be used to select multipliers for correcting volumes to standard temperatures, the hydrometer reading should be made preferably at a temperature within +/-3°C (+/-5°F) of the temperature at which the bulk volume of the oil was measured.

8.4. DEFINITIONS

8.4.1. Density

For the purpose of this method, the mass (weight in volume) of liquid per unit volume at 15°C. When reporting results, explicitly state the density in units of mass (kilograms) and volume (liters) together with the standard reference temperature, e.g., kilograms per liter at 15°C.

8.4.2. Specific Gravity

Specific Gravity is defined for the purpose of this method, as the ratio of the mass of a given volume of liquid at 60°F to the mass of an equal volume of pure water at the same temperature. When stating results, explicitly report the standard reference temperature, e.g., specific gravity 60/60°F.

8.4.3. API Gravity

A special function of specific gravity 60/60°F represented by:

API gravity, deg. = (14.5/sp gr 60/60°F) – 131.5

No statement of reference temperature is required, since 60°F is included in the definition.

8.4.4. Observed Values

Since all hydrometers are calibrated to read corrected at a specified reference temperature, values observed at other temperatures are only hydrometer readings and not density, specific gravity, or API gravity at that other temperature.

8.5. APPARATUS

8.5.1. Hydrometers

Glass hydrometers are graduated in units of density, specific gravity or API gravity as required, conforming to ASTM specifications or specifications of the British Standards Institution

8.5.2. Thermometers

Thermometers have ranges and conform to specifications of the ASTM or the American Petroleum Institute.

8.5.3. Hydrometer Cylinder

These are made of clear glass, plastic, or metal. For convenience in pouring, the cylinder may have a lip on the rim. The inside diameter of the cylinder shall be at least 25 mm greater than the outside diameter of the hydrometer used in it. The height of the cylinder shall be such that the hydrometer floats in the sample with at least 25 mm clearance between the bottom of the hydrometer and the bottom of the cylinder.

Note: Hydrometer cylinders constructed of plastic materials must be resistant to discoloration or attack by oil samples and must not become opaque under prolonged exposure to sunlight and oil samples.

8.5.4. Constant Temperature Bath

These are used when the nature of the sample requires a test temperature much above or below room temperature.

Note: The user should ascertain that the instruments used for this test conform to the requirements set out above with respect to materials, dimensions, and scale errors. In cases where the instrument is provided with a calibration certificate issued by a recognized standardizing body, the instrument is classed as "certified”, and the appropriate corrections listed shall be applied to the observed readings. Instruments which satisfy the requirements of this test method but are not provided with a recognized calibration certificate are classified as "uncertified."

8.6. PROCEDURE

Step Procedure 1 Adjust the temperature of the sample according to the indications given above. Bring the hydrometer cylinder and thermometer to approximately the same temperature as the sample to be tested.

Note: When testing completely opaque samples, metal hydrometer cylinders may be used.

When such cylinders are used, accurate reading of the hydrometer can only be assured if the level of the sample is within 5 mm of the top of the cylinder.

2 Transfer the sample to a clean hydrometer cylinder without splashing to avoid the formation of air bubbles and to reduce to a minimum the evaporation of the lower boiling constituents of the more volatile samples to the cylinder by water displacement or by siphoning. Remove any air bubbles formed, after they have collected on the surface of the sample by touching them with a piece of clean filter paper before inserting the hydrometer.

Note: Highly volatile samples containing alcohols or other water-soluble material should always be transferred by siphoning.

3 Place the cylinder containing the sample in a vertical position in a location free from air currents. Ensure that the temperature of the sample does not change appreciably during the time necessary to complete the test; during this period, the temperature of the surrounding medium should not change more than 2°C (3.6°F). When testing at temperatures much above or below room temperature, a constant-temperature bath may be necessary to avoid excessive temperature changes.

4 Lower the hydrometer gently into the sample. Take care to avoid wetting the stem above the level to which it will be immersed in the liquid. Continuously stir the sample with the thermometers, ensuring that the stem of the hydrometer is not wetted above the immersion level. As soon as a steady reading is obtained, record the temperature of the sample to the nearest 0.1°C (0.1°F) and then remove the thermometer.

5 Depress the hydrometer about two scale divisions into the liquid and then release it. The remainder of the stem of the hydrometer which is above the level of the liquid must be kept dry since unnecessary liquid on the stem affects the reading obtained. With samples of low viscosity, impart a slight spin to the hydrometer on releasing to assist in bringing it to rest, floating freely away from the walls of the cylinder. Allow enough time for the hydrometer to come to rest and for all air bubbles to come to the surface. This is particularly necessary in the case of more viscous samples.

6 When the hydrometer has come to rest, floating freely away from the walls of the cylinder, estimate the hydrometer scale reading to the nearest 0.001 sp gr or density or 0.05 deg API.

The correct hydrometer reading is that point on the hydrometer scale at which the principal surface of the liquid cuts the scale. Determine this point by placing the eye slightly below the level of the liquid and slowly raising it until the surface, first seen as a distorted ellipse, appears to become a straight line cutting the hydrometer scale.

7 With an opaque liquid, take a reading by observing with the eye slightly above the plane of the surface of the liquid, the point on the hydrometer scale to which the sample rises. This reading, at the top of the meniscus, requires correction since hydrometers are calibrated to be read at the principal surface of the liquid. The correction for the particular hydrometer in use may be determined by observing the maximum height above the principal surface of the liquid to which oil rises on the hydrometer scale when the hydrometer in question is immersed in a transparent oil having a surface tension similar to that of the sample under test.

8 Immediately after observing the hydrometer scale value, again cautiously stir the sample with the thermometer keeping it fully immersed. Record the temperature of the sample to the nearest 0.1°C (0.1°F). Should this temperature differ from the previous reading by more than 0.1°C (0.1°F), repeat the hydrometer and then thermometer observations until the temperature becomes stable within 0.1°C (0.1°F).

Note: After use at a temperature higher than 38°C (100°F), allow all hydrometers of the lead shot in wax type to drain and cool in a vertical position.

8.7. CALCULATIONS AND REPORT

Apply any relevant corrections to the observed thermometer reading (for scale or bulb) and to the hydrometer reading (scale). For opaque samples, make the appropriate correction to the observed hydrometer reading as given in 10.6.7. Record to the nearest 0.0001 density or specific gravity, or 0.1 deg API of the final corrected hydrometer scale reading. After application of any relevant corrections, record to the nearest 0.1°C or 0.1°F, the mean of the temperature values observed immediately before and after the final hydrometer reading.

Note: Hydrometer readings at temperatures other than calibration temperatures (15°C or 60°F) should not be considered as more than scale readings.

To convert corrected values from Paragraph 10.7, Item 1 to standard temperature, use the following from the Petroleum Measurement Tables.

• When a density-scaled hydrometer has been employed, use Table 53* to obtain density at 15°C.

• When a specific gravity hydrometer has been employed, use Table 23* to obtain Specific Gravity

60/60°F.

• When an API gravity-scaled hydrometer has been employed, use Table 5* to obtain the gravity in

API degrees.

When a value is obtained with a hydrometer scaled in one of the units described herein and a result is required in one of the other units, make the conversion by one of the appropriate tables given in the Petroleum Measurement Tables. For conversion from density at 15°C, use Table 51*; from specific gravity 60/60°F, use Table 21*; from API gravity, use Table 3*.

Report the final value as density in kilograms per liter at 15°C, or as specific gravity at 60/60°F, or as gravity in degrees API, as applicable.

8.8. PRECISION AND ACCURACY

The following criteria should be used for judging the acceptability of results.

1. Repeatability: Duplicate results by the same operator should be considered suspect if the results differ by more than the following amounts.

Product Temperature Range Units Repeatability Transparent -2 to 24.5°C Density 0.0005 Non-viscous 29 to 76°F Specific gravity 0.0005 42 to 78°F API gravity 0.1000 Opaque -2 to 24.5°C Density 0.0006 29 to 76°F Specific gravity 0.0006 42 to 78°F API gravity 0.2000

2. Reproducibility: The results submitted by each of two laboratories should not be considered suspect unless the results differ by more than the following amounts:

Product Temperature Range Units Repeatability Transparent -2 to 24.5°C Density 0.0012 Non-viscous 29 to 76°F Specific gravity 0.0012 42 to 78°F API gravity 0.3000 Opaque -2 to 24.5°C Density 0.0015 29 to 76°F Specific gravity 0.0015 42 to 78°F API gravity 0.5000

3. For very viscous products, or when the conditions given in Paragraph 10.8, #2, and 10.8, #3, are not complied with, no specific variations can be given.

8.9. REFERENCES

1. ASTM Standards, Method D287-67, Standard Test Method for API Gravity of Crude Petroleum and Petroleum Products (Hydrometer Method).

2. ASTM Standards, Method D1298-67, Standard Practice for Density, Relative Density (Specific Gravity), or API Gravity of Crude Petroleum and Liquid Petroleum Products by Hydrometer Method.

9. DENSITY – INSTRUMENTAL METHOD (ULTRASONIC)

9.1. SCOPE OF APPLICATION

The instrumental method measuring density employs the oscillating body principle. In use in the Ohmsett lab is the Mettler-Toledo Densito 30-PX densitometer. In it, a precisely made and calibrated quartz tubular cell is filled via vacuum withdrawal of the liquid sample.