Title: Introduction Text: The purpose of this tool is to help Remedial Project Managers (RPMs) ensure that proper groundwater sampling protocols are followed by their contractors in the field. The use of incorrect field procedures may adversely affect data quality and impact the ability of RPMs to make sound decisions for site cleanup. RPMs should include specific sampling procedures in the statement of work for each project and should have the ability to audit contractors in the field. The following topics are covered in this tool to assist RPMs with contractor oversight: Pre-field sampling activities Procedures for low-flow, high purge, and passive diffusion bag (PDB) sampling Quality Assurance/Quality Control (QA/QC) measures Field audit, including a customized audit form that may be created and printed out from the field audit section of this tool. Data management

Title: Pre-Field Activities Text: Challenges will present themselves once work begins in the field, but proper planning can make them more readily manageable. There are many things that your contractor should accomplish well before beginning field work, including: Contacting an analytical laboratory to establish the analytical methods that will be performed, have sample collection containers shipped, and establish sample shipping/transport procedures Preparing the Sampling and Analysis Plan (SAP) Preparing the Site-Specific Health and Safety Plan (HASP) Gathering the applicable forms and/or creating a field logbook Purchasing the necessary supplies and/or making arrangements for equipment rental Inspecting the field equipment and vehicle

Title: Mobile Laboratory Considerations Text: If a mobile laboratory was to be used for a delineation project, 10% of the samples should have a duplicate or split sample sent to a fixed laboratory for analysis. Additionally, a portion of the samples should be sent to a fixed laboratory to confirm the outer boundaries, typically 20% of the samples.

Title: Analytical Laboratory (1 of 3) Text: As part of the field preparation, an analytical laboratory should be contracted and scheduled to perform chemical analyses on the groundwater samples. The selected laboratory must be approved for use in the Navy Installation Restoration (IR) Program. A laboratory must meet specific requirements and pass an assessment to be accepted for use in the Navy IR program. These requirements are outlined in the Navy Installation Restoration Chemical Data Quality Manual (NAVFAC, 1999).

Title: Laboratory (2 of 3) Text: Specific arrangements should be made by your contractor ahead of time regarding the methods to be performed for targeted chemical analytes, the length of time for sample turnaround, how the results will be reported, and the level of data validation that will be required. Analytical laboratories provide the necessary sample bottles, coolers, packing materials, and chain-of-custody forms. It is important the contractor to obtain sampling requirements (such as the proper container, sample volume, preservative, and holding times) so they may be incorporated into the SAP. Method detection and quantification (or reporting) limits should also be discussed with the laboratory to ensure that they are lower than regulatory limits. The information discussed covers primarily fixed laboratories, other considerations may be important if a mobile laboratory is used.

Title: Laboratory Analytical Methods (2 of 3) Text: Depending on which analytical methods are included in the SAP, the required number, size, and material of sampling bottles may be different. Additionally, the samples may require addition of a preservative, such as hydrochloric or nitric acid. Sample holding times will vary according to the type of analysis being performed. It is important to know this type of information ahead of time to ensure that samples are collected and preserved properly and received by the laboratory within the given holding time. If instructions are not followed properly, samples may no longer be representative of the target groundwater conditions. The table to the left shows several common analytical methods, sampling container requirements, preservation method (if any), sample holding times, and special sampling instructions. Including a similar table in the SAP is very useful.

Title: Text: The holding time is the maximum amount of time that may pass between sample collection and sample analysis.

Title: Sampling and Analysis Plan Text: The main objectives of the SAP are to describe specific field sampling procedures and to establish data collection, handling, and documentation methods that will provide quality results. Quality control objectives and sampling requirements are also discussed and established in the SAP. Some of the important elements included in a SAP for groundwater monitoring are groundwater sample collection methods and locations, sampling frequency, analytical requirements, data quality objectives, data management procedures, decontamination procedures, and residual waste disposal procedures. A copy of the SAP should always be available for use by contractors in the field.

Title: Health and Safety Plan (1 of 2) Text: The site-specific HASP outlines procedures to ensure the health and safety of site personnel. The HASP includes personnel training requirements, anticipated weather conditions and precautions, job hazard analysis including hazard communication, medical program, personal protective equipment (PPE) requirements, site control, and emergency response. Emergency contact numbers including the fire department, police department, hospital, and a base contact should be included in the HASP. A copy of the HASP should be present on-site during all field activities.

Title: Personal Protective Equipment (2 of 2) Text: PPE is designed to eliminate or reduce exposure to hazards in the workplace. The site-specific PPE required for groundwater sampling activities should be outlined in the HASP. Typically, groundwater sampling presents Level D site conditions. The PPE required by the Occupational Safety and Health Administration (OSHA) for Level D includes: Work pants and shirt and/or coveralls Steel-toed boots Gloves Safety glasses Splash-proof goggles if using hazardous liquids Hardhats when overhead hazards are present.

Title: Field Activity Documentation Text: A field activity log book or other appropriate forms should be used by your contractors to document all events as they occur. Enough detailed information should be included so that events can be reconstructed by someone not present during field activities. All field notes should be written in black ink. Other relevant information that should be documented include field personnel, date, time for each activity, sampling locations, type of sample collected and analyses required, equipment utilized, instrument readings, and calibration information. Site-specific forms prepared prior to the field activity may be useful and help streamline the sampling process for contractors. Examples of forms that may be utilized are monitoring well water level logs, purge logs, and equipment calibration logs. Please click here to see an example of a well purge log form.

Title: Field Activities - Work Area (1 of 4) Text: Upon arrival at the groundwater sampling location, the work area must be established. The first step is to locate the monitoring wells and identify any special needs or potential challenges associated with any of them. A decontamination area also may be set up, if appropriate for the specific site and sampling method. If purge water will be generated, the appropriate storage container should be identified and labeled. If necessary, barricades may be set up surrounding the well locations to prevent pedestrians from entering areas that may be hazardous and to alert drivers or other vehicle operators of the work zone.

Title: Field Activities - Instruments (2 of 4) Text: Field instruments, including water level indicators and water quality meters, should be inspected daily and calibrated as required to ensure that they are functioning properly and providing accurate measurements. If an instrument does not pass an inspection, it should be sent for maintenance and repair and not used. Methods for calibration should be followed according to the manufacturer’s recommendations. Field instruments should be calibrated each day before and after use. If the calibration check at the end of the work day does not meet acceptance criteria, instrument calibration checks may be required more often during the day. All information relating to instrument calibration and maintenance should be recorded in the field log book.

Title: Field Activities - Well Inspection (3 of 4) Text: Prior to sampling, a monitoring well should be inspected to make sure that no damage has occurred since the last sampling event. Comparisons should be made between the observed condition and records from the last sampling event. A visual inspection of the outside of the well should be made first. Things to inspect include the integrity of the concrete pad, stickup well vault (if applicable), and bollards surrounding the well. The presence of ponded water around the well should be noted in the log. Once well caps for all site have been opened (to allow time for equilibration), the inside of each well (either flush or stickup) should be checked for a locking well seal or cap on the casing (if the vault itself was not locked), a bent or obstructed well casing, and water buildup surrounding the upper portion of the well casing (more of a concern for flush wells). Once the well has been inspected and the water table has equilibrated (evidenced by water level measurements that remain unchanged with time), a water level measurement should be taken and recorded. Water level measurements for all site wells should be measured within a short period of time (synoptically) and from the least contaminated to most contaminated well ("cold" to "hot").

Title: Field Activities - Containers and Labels (4 of 4) Text: Each sample label should contain a unique identification (ID), which will make it easily identifiable when results are received. Typically, the well sample ID will include the monitoring well ID, the date of collection, and additional identifiers for specialty samples (i.e., quality assurance samples). Sample labels should be filled out using dark permanent ink and covered with clear tape to prevent smearing. The following information should be included on each label (at a minimum): Sample ID, Sample collection date (month/date/year), Time of collection using a 24-hour clock, Project ID, Sampler’s initials, Analysis that will be performed, and Preservative (if applicable) QA/QC identifiers

Title: Sampling Methodologies Text: There are several different methods for collecting groundwater samples. Some of the acceptable methods include low-flow purge and sample, high-flow purge and sample, and passive diffusion bag sampling. All methods may not be suitable for every site. When determining which method is suitable for a specific site, things for contractors to consider include: Data Quality Objectives Sampling method applicability to site contaminants of concern Site geology and hydrology Monitoring well construction Purge recovery rate Cost Disposal of residual purge water Contaminant stratification Preferential pathways Chemical and physical characteristics of analytes The sampling method should be selected in agreement with regulatory stakeholders and described in the SAP.

Title: Low-Flow Sampling - Introduction (1 of 4) Text: Low-flow purge and sample is appropriate for volatile organic compounds (VOCs), semi-volatile organic compounds (SVOCs), pesticides, polychlorinated biphenyls (PCBs), and inorganics including metals, radionuclides, nutrients, and salts. Low-flow purge sampling refers to the volumetric flow rate at which the water is extracted from the monitoring well. The volumetric flow rate should be low enough to prevent drawdown in the monitoring well. The following criteria must be met in order for low-flow purge and sample to be applicable: Well must have the ability to be pumped at a constant flowrate, typically 0.1 to 1.0 liters/minute, without causing drawdown greater than 4 inches The well screen must be less than 20 ft in length

Title: Flowrate Considerations (2 of 4) Text: Although low-flow sampling specifies a maximum purge flowrate of 1 liter/minute, there are several other considerations when determining the optimal purge flowrate. The optimal flowrate should be determined based on the hydraulic performance of the well observed during well development. Purging should cause only minimal drawdown of the water level in the well and be low enough to prevent turbidity in the purged water. Purge flowrates should remain consistent among sampling events at any given well. If excessive water level fluctuations are observed in a monitoring well, the well may require redevelopment and re-measurement of the optimal purge flowrate.

Title: Pump or Tube Placement (3 of 4) Text: The purge pump or sampling tube placement depth can be determined based on the site lithology and well construction details. Generally, the tube/purge pump is placed in the middle of the screened interval of a monitoring well. If geological conditions are heterogeneous, it may be necessary to place the tube/purge pump at a depth of preferential flow or in a previously identified zone of concern. The tubing should be lowered into the well slowly to minimize disturbance to well water. Once the tube has been placed at the correct depth, the water can then be pumped out of the well. Pumped water is drawn through a flow-through cell, which contains a water quality meter that measures temperature, oxidation-reduction potential (ORP), dissolved oxygen (DO), turbidity, pH, and electrical conductivity. Water quality parameters should be recorded on a sampling log at appropriate time intervals (determined in SAP) and compared to the previous measurement. When parameters have stabilized, a groundwater sample can be collected.

Title: Sample Collection (4 of 4) Text: Once water quality parameters have stabilized, groundwater should continue to be pumped at the same low flowrate. This list of guidelines should be followed by contractors while sampling: New, clean, and chemical resistant gloves should be worn by the sampler, Appropriate sample bottles should be used for each analysis included in the SAP, Sample bottles should be filled with groundwater in a manner to minimize aeration, Samples should not be transferred from one container to another, Sample labels should be placed on bottles immediately following sample collection, and Samples should be placed in coolers on ice immediately following collection. Samples should be collected in progression from "cold" to "hot" wells.

Title: High-Flow Purge - Introduction (1 of 2) Text: High-flow purge and sample involves purging water from a monitoring well at a rate greater than 1 liter/minute, which is typically not suited for low yield wells. Low yield wells recharge slowly and purging too fast can produce significant drawdown or even purge the well dry, which can cause increased turbidity and alteration of the water chemistry. Typically, three borehole volumes should be purged from the well prior to sample collection. The equation for calculating the borehole volume is shown to the left.

Title: Sample Collection (2 of 2) Text: High purge can be accomplished by using either a pump or a bailer. If a pump is used, it should be placed in the lower one-third of the well. The well should be purged in a manner that will not cause cross-contamination or aeration of the sample being collected. As mentioned earlier, three borehole volumes of water should be purged from each well. If water quality parameters are monitored, less water may be purged depending on the point in the purging process that equilibrium (steady water quality parameter values) is reached. Samples should be collected using the same precautions mentioned previously in the low-flow sampling section. The sample may be collected using the same equipment that was used to purge the well (bailer or pump).

Title: Passive Diffusion Sampling - Introduction (1 of 3) Text: Passive diffusion sampling can be a cost-effective method for groundwater sampling. Passive diffusion bag (PDB) samplers are typically composed of low-density polyethylene (LDPE) and contain deionized (DI) water. Use of LDPE PDB samplers are limited to sampling for VOCs. New PDB materials are being studied to broaden the applicability of this sampling technique to other types of compounds, but are not commercially available. Factors that could affect the quality of the sample collected include groundwater velocity, hydraulic conductivity, hydraulic gradient, preferential flow within the water column, and placement of the PDB within the well. The following site conditions are generally appropriate for groundwater sampling using PDB samplers: Groundwater velocity greater than 0.5 ft/day (1.76E-04 cm/sec) Hydraulic conductivity greater than 1.0E-05 cm/sec Hydraulic gradient greater than 0.001 If these conditions are not met or contaminants other than VOCs are present, another method of groundwater sampling should be used.

Title: Passive Diffusion Sampling Methodology (2 of 3) Text: PDBs can be designed to accommodate different well sizes and sampling requirements; however, they should not exceed 5 ft in length. If a screened interval in a monitoring well is greater than 5 ft, multiple PDB samplers should be deployed. Under the natural groundwater gradient, chemicals diffuse across the LDPE bag sampler (typically 0.1 millimeters thick) until chemical concentrations inside the bag are equal to those in the groundwater surrounding the monitoring well. A minimal deployment time for PDB sampling is about two weeks. Samplers have been left in wells for as long as three months without compromising the integrity of the bag. If monitoring is conducted quarterly, a three-month deployment would allow bags to be retrieved and replaced in the same field event.

Title: Advantages of Using PDB Samplers (3 of 3) Text: There are many advantages to using PDB sampling over other conventional sampling methods, including: PDB samplers are easy to deploy and recover PDB sampling almost or entirely eliminates purge water, reducing or eliminating the cost for its disposal Eliminates turbidity in samples Multiple PDBs can be used for vertical profiling of contaminants in a monitoring well without mixing Costs can be much lower using passive sampling techniques because of reduced labor and lower equipment costs Equipment decontamination is not necessary because sampling bags are disposable There is less wear and tear on the monitoring well There is no need to collect and analyze equipment blanks because equipment does not need to be decontaminated

Title: Chain of Custody (1 of 4) Text: Chain of custody forms are used as a way of documenting a sample's physical location from the time of collection to receipt by the laboratory. They can also be used by contractors to make specific requests to the laboratory such as fast turn around time, special reporting limits, or specific data deliverable requirements. All samples that are shipped or transported should be accompanied by a chain of custody. If more than one cooler is used for the samples collected on the same day, separate chain of custody forms should be included in each cooler. Placing the chain of custody form in a plastic bag will keep it from getting wet. The sampler must sign the chain of custody prior to shipment, releasing samples from his/her "custody." Chain of custody seals are often provided by laboratories for shipment. Upon receipt of the samples, the laboratory must sign the chain of custody claiming "custody" of them. A copy of the signed chain of custody must be included with laboratory analytical reports.

Title: Sample Shipment (2 of 4) Text: Proper shipment of sample bottles will ensure that quality samples are received by the laboratory. Sample bottles should be individually wrapped in bubble wrap to prevent breakage during transport. The remaining space should be filled with ice to maintain a 4 degree Celsius temperature until the samples are received by the laboratory. Ice should be placed in sealable storage bags to prevent leaks, which could cause delays in delivery and the potential for exceeding hold times. Packing tape should be wrapped around the cooler to ensure that it does not open while being shipped. In order for the laboratory to receive samples as soon as possible, an overnight shipping service with the ability to track packages should be used.

Title: Decontamination Procedures (3 of 4) Text: Decontamination is a four-step process that needs to be completed on all non-dedicated or non-disposable field equipment to avoid cross contamination between samples and to ensure the health and safety of field personnel. The following sequence should be used by your contractors to clean equipment and sampling devices before and between each use: Wash with non-phosphate detergent and tap water and clean with a stiff-bristle brush. Rinse with distilled water Rinse with reagent-grade methanol Rinse with high-performance liquid chromatography-grade water Place the sampling equipment on a clean surface and air-dry

Title: Waste Disposal (4 of 4) Text: During sample collection, wastes such as disposable sampling equipment, purge water, decontamination water, and used PPE may be generated. Procedures for disposal of these items should be outlined in the SAP. It may be necessary for contractors to receive laboratory results before the waste can be properly disposed. During this time, waste should be properly stored and labeled.

Title: Field Audit Form Text: Field audits may be conducted by RPMs to verify that contractors adhere to the SAP and implement practices that are consistent with Navy and EPA protocols to achieve a high level of data quality while performing groundwater sampling. In most cases, a field audit would be conducted unannounced. A checklist might be used to perform a field audit. Some of the items that may be included in an audit are: HASP, PPE, instrument calibration procedures, sampling procedures, proper decontamination procedures, and waste disposal procedures. Click on the button to create and print a project-specific field audit form. If deficiencies are observed in a first audit, a second audit may be conducted to confirm that corrective actions have been implemented. Performance of field audits ensures that the field data produced by contractors are reliable and representative.

Title: Quality Assurance and Quality Control (1 of 3) Text: It is important to implement the Quality Assurance and Quality Control (QA/QC) plan, which should be incorporated into the SAP, while performing groundwater sampling. The quality of field data can be quantitatively assessed through collection and analysis of field QC samples. Qualitative analyses can also be performed by reviewing field notes to verify that sampling protocols have been followed. Laboratory QC samples are analyzed in accordance with analytical method protocols to ensure that proper laboratory procedures are being followed.

Title: Field QC Samples (2 of 3) Text: Field QC samples should be collected and analyzed to assess project consistency. Field QC sample types include the following: field duplicates, trip blanks, field blanks, and rinse blanks. Generally, the number of field QC samples collected is 10% of the total number of field samples collected. The precision of the results from field duplicate samples is calculated by the relative percent difference (RPD) of the two samples which measures the reproducibility of the duplicate measurements. The acceptable RPD for field duplicate samples is usually 30%. Trip blanks, field blanks, and rinse blanks should not have detectable concentrations of chemicals.

Title: RPD Text: The RPD is determined by calculating two times the difference in the results divided by the sum of the results, times 100%.

Title: Text: Field duplicates consist of two groundwater samples collected consecutively from the same location using the same sampling techniques. Field duplicates are used to evaluate the precision of the sample collection and analysis process.

Title: Text: Trip blank samples accompany each shipment that contains samples that will be analyzed for VOCs. Trip blanks are prepared at the laboratory by filling 40-mL volatile organic analysis (VOA) vials with high-performance liquid chromatography-grade water. Trip blanks are never opened in the field.

Title: Text: Field blanks are collected to check on reagent and environmental contamination. Sample bottles are filled with distilled or DI water and placed uncapped upwind of a monitoring well during sample collection. Once a sample has been collected from the monitoring well, the field blank containers are capped and analyzed for the same chemicals as the rest of the samples.

Title: Text: Equipment rinsate blanks (rinse blanks) are collected to ensure that non-dedicated sampling devices are decontaminated effectively. After sampling devices have been decontaminated, distilled or DI water is conducted through or over the object(s) and collected in the proper sampling container. Rinse blanks are analyzed for the same chemicals as the rest of the collected groundwater samples.

Title: Laboratory Quality Assurance (3 of 3) Text: The analytical laboratory also must perform QC procedures in accordance with internal standard operating procedures (SOPs). Laboratory QC samples include initial and instrument check calibrations, method blanks, control samples, lab duplicates, and matrix spikes. If data quality objectives are not met, laboratory corrective action may be necessary. Corrective actions are included in the laboratory's QA plan. Reanalysis of samples may be necessary once the laboratory problem causing the deficiency is identified and corrected.

Title: Text: The objective of calibration checks is to ensure that the instrument is producing results that correlate with known concentrations. Initial calibrations are performed with a frequency described in the laboratory Quality Assurance Plan, and again whenever the continuing calibrations fail to meet their respective acceptance criteria. Continuing calibration checks are used to verify that the instrument performance has remained within the limits established at the time of initial calibration.

Title: Text: The objective of method blanks is to detect contamination of samples collected in the field that may occur once samples have arrived at the laboratory. Method blanks verify that method interference caused by potential laboratory contaminants in solvents, reagents, glassware, or other sample-processing hardware are known and minimized. Method blanks contain distilled or DI water.

Title: Text: The objective of laboratory control samples is to check the accuracy of the laboratory analytical procedures by measuring a known concentration of an analyte in interference-free media, called blank spike samples. Blank spike and blank spike duplicate samples are prepared by the laboratory using clean laboratory media spiked with the analysis target compounds.

Title: Text: The objective of laboratory duplicates is to determine the precision associated with the laboratory process. Laboratory duplicates are two aliquots of a sample taken from the same sample bottle and analyzed independently. The results of the two assays are compared and the relative percent difference is calculated to measure the precision of the analysis.

Title: Text: Matrix spikes (MS) and matrix spike duplicates (MSD) are used to check the precision and accuracy of analytical methods by analyzing an environmental sample with a known contaminant concentration. Additional bottles of sample are collected in the field in the same manner as a field duplicate. Two portions of the sample are spiked with a standard solution of target analytes at the laboratory. The MS and MSD samples are analyzed for the same chemicals as field samples. The results can reveal if matrix interference exists that amplifies or dampens the signal from a known concentration of contaminant.

Title: Data Management - Electronic Data (1 of 3) Text: Field observations and measurement data should be recorded by your contractors in the field notebook and on field forms to provide a permanent record of field activities. All logbooks, field forms, databases, and electronic spreadsheets should be checked for completeness. Accurate field documentation ensures the quality of the collected samples and provides enough information to recreate each field event if necessary. Hard copy originals of all analytical data should be received from the laboratory. The laboratory should also provide an electronic data deliverable (EDD), which is a formatted electronic file containing the analytical data. Click here for more information on the EDD format required for the Navy Installation Restoration Information Solution (NIRIS) database.

Title: Data Management - Validation (2 of 3) Text: Data validation is the process of evaluating data and accepting or rejecting it based on a set of predetermined data quality objectives. An analytical laboratory will provide a data package for the specified level of validation. Typically, Level-4 data validation, which is based on assessment of the complete raw data package, is performed on 10% of the collected samples. Additionally, instrument performance, calibration methods, and calibration standards are reviewed to ensure that the detection limits and data values are accurate and appropriate. The remaining 90% of collected samples are validated at Level 3, which assumes that reported data values are correct. Data quality is assessed by verifying that the criteria defined in the SAP have been achieved for each compound class. Data validation must be performed by an independent third party reviewer.

Title: Data Management - Evaluation (3 of 3) Text: Once data is received and tabulated it must be summarized and presented in a logical, meaningful way. Click on the links below to view examples of methods of data presentation including: Statistical - Statistical tools are used to quantify values and data variation. Graphical - Graphical representation of data can be used to visually illustrate trends, data anomalies, and systematic patterns. Tabular - Tabular formats can be used as a means of summarizing the data. 3-Dimensional (3-D) Plot - 3-D plots are used to display the extent of a contaminant plume.

Title: References/Links Text: Department of Defense (DOD). 2004. DoD Quality Systems Manual for Environmental Laboratories. December. EPA CLU-IN Web Site. Characterization and Monitoring. http://clu-in.org/char1.cfm ERB Web Site. Groundwater Monitoring. NAVFAC. 1999. Navy Installation Restoration Chemical Data Quality Manual (IR CDQM), NFESC Special Report SP-2056-ENV . 1999. Radian International. 2000. Interim Final Guide to Optimal Groundwater Monitoring. Prepared for Naval Facilities Engineering Service Center, Port Hueneme, California. January. San Diego County. 2004. Site Assessment and Mitigation (SAM) Manual. February 18.

Title: Contact Text: For more information about Groundwater Sampling, please contact: NFESC POC (805) 982-1656 PRTH_NFESCT2@navy.mil