CHAPTER 17: CHAPTER 17: SAMPLING AND ANALYSIS PROCEDURES
17.1 Sampling and Analysis Planning
Many of the standard operating procedures in the Lead HaTard Management Plan include sampling and analytical
requirements for lead in air, soil, dust, paint and wastes. This chapter addresses the steps that are necessary to ensure that appropriate, reliable sampling and analytical data are obtained to support the decision making process. As outlined in Figure
17.1, the critical tasks include establishing data collection objectives; developing a sampling and analytical plan that implements procedures for quality control and documentation;
conducting the sampling and analysis; and compiling the report.
17.1.1 Data collection objectives
The first task in developing a sampling and analytical plan is to establish the data collection objectives. The stated objectives should address the following questions:
9 Why is the data needed?
9 What questions should the data answer?
9 What decisions will be made based on the data?
9 What level of statistical confidence is required?
9 What data is required for inclusion in reports for regulatory or contract compliance?
Table 17.1 summarizes some of the typical lead ha7zrd control activities, the types of samples typically collected, and their purpose.
17.1.1.1 Questions to be answered
The types of questions to be answered can be illustrated by conducting an interior lead abatement project involving wet scraping of lead-based paint from windows, door frames and molding.
It is likely that personal air samples and dust wipe samples would be collected. Personal air samples to determine worker exposures are required by OSHA. The question to be
answered by the personal exposure data is the "What is the airborne concentration of lead in the worker's breathing zone over an entire shift?" The data will be used to determine if
Figure 17.1: Sampling and Analysis
Establish data collection objectives
II
Develop plans for efficient sampling and analysis
Determine regulatory requirements
+
Select standards & practices
II
Determine quality control requirements
Document sampling location and chain of custody
Use appropriate methods to sample and analyze for lead
Use appropriate methods to sample and analyze for other project materials and
conditions
Compile report
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Table 17.1 Summary of Types of Samples for Lead Hazard Control Activities ACTIVITY As part of a Risk Assessment Paint Inspections Prior to a lead hazard control activities During lead hazard control activities After completion of lead hazard control activities Prior to disposal of waste generated during lead hazard control activities PURPOSE To assess the potential for a lead exposure hazard I;o identify locations of lead- based paint To determine baseline concentrations To determine the effectiveness of containment To measure worker exposures To determine if the area is suitable for re-occupancy To determine if the material is a characteristic hazardous waste TYPE OF SAMPLE(S) Dust wipe Dust vacuum Soil Sometimes water X-Ray Fluorescence Paint chips I Chemical spot tests Dust wipe Soil Dust wipe Air Dust wipe Bulk
ASTM SAMPLING AND ANALYTICAL METHOD(S)/PROCEDURES Dust wipe sampling (ASTM E 1728, E 1792, and E 1644) Dust vacuum sampling (ASTM E 1973 and E 1644) Soil sampling for lead (ASTM E 1727 and E 1726) Water sampling for lead (ASTM D 3559, E 1726, and D 5463) In situ lead analysis by XRF (ASTM E 1755) Paint chip sampling and analysis (ASTM E 1729, E 1645, and E 1613) Chemical spot test kit measurements (ASTM E 1753 and E 1828) Dust wipe sampling (ASTM E 1728, E 1792, and E 1644) Soil sampling for lead (ASTM E 1727 and E 1726) Dust wipe sampling (ASTM E 1728, E 1792, and E 1644) Air sampling for lead (ASTM E 1553 and E 1741) Dust wipe sampling (ASTM E 1728, E 1792, and E 1644) Waste analyses for EPA 40 CFR 261 determination (ASTM E 1908 and Appendix II - Method 131 l, 40 CFR Part 261) May also be used to determine leaded paint
the worker's exposures are over or under the OSHA
permissible exposure limit (50 ~tg/m 3 as an 8-hour TWA) and if the level o f respiratory protection provided to the worker is appropriate.
Dust wipe samples might be collected outside the containment area to determine if lead dust is effectively contained by engineering controls and work practices. The question to be answered by perimeter dust wipe samples would be "Are the concentrations o f lead dust on surfaces outside, but near the containment area, the same during abatement as they were before abatement began?" The data will be used to either document that containment was effective or to indicate that procedures need to be modified to minimize the spread o f contamination outside the containment area.
Dust wipe samples may also be collected inside the abatement area once work is completed to determine if the area is acceptable for reoccupancy by unprotected personnel. The question to be answered by the clearance dust sample data is
"are the levels below applicable clearance criteria." The data will be used to determine if the work area is "clean" or if certain areas or components need to be recleaned and retested.
17.1.1.2 Level of confidence needed
With any type of sample collected there will be a discrepancy between the measured and the true concentration, which occurs as a result of random sampling error, analytical error, and random environmental fluctuations. Basically, the more samples that are collected, the more likely the measured concentration will represent the actual concentration. There are statistical methods that can be used prior to collecting samples to determine how many samples should be collected to achieve a desired level o f confidence. Typically a 95%
confidence level is considered acceptable for most environmental sampling situations.
For example, Appendix A-12 o f the HUD Guidelines
addresses the statistical rationale for the number of units to be inspected for lead-based paint in multifamily housing. The basic specification o f the sampling scheme is that it achieves 95% confidence. Suppose one follows this sampling scheme and tests for lead-based paint in 100 units, and finds all surfaces tested are below 1 mg/cm 2 lead in paint. The inspector may state with 95% confidence there was no lead- based paint found. Put another way, the inspector may conclude that at least 95 o f the 100 units do not have lead- based paint.
17.1.1.3 Reporting requirements for data
How the data will be reported should be determined before sampling is conducted. Issues to be considered regarding reporting the data include the following:
9 Format o f the data
9 Frequency o f data reporting 9 Regulatory requirements 9 Contractual requirements 9 Other supporting information
As a general rule the data should be reported in a concise summary format, followed by detailed information. The summary usually contains the following information:
9 Date o f sampling
9 Type o f samples collected 9 Location of each sample 9 Description o f each sample 9 Sample results
The detailed information will include the same information plus additional data. The additional data will usually include the following:
9 Who collected the samples 9 Time o f sample
9 Chain-of-custody form 9 Calibration data, as needed
9 Name and address o f the laboratory (if applicable) 9 Who performed any analyses
9 Results of blank and quality control samples 9 Diagram showing sampling locations 9 Which standard methods were used 9 How sample locations were selected
9 Accreditation/certification information for sampling and analytical personnel/organization(s)
The frequency o f data reporting depends on the need for information. On some lead hazard abatement projects it may be necessary or desirable to report air sampling or dust sampling results on a daily (within 24 hours) basis. For periodic dust wipe sampling the frequency o f sampling and reporting may be every 3 months, 6 months, or annually.
How the data is reported may be dictated, at least to some extent, by regulatory or contractual requirements. Samples collected for compliance with the OSHA lead standard(s) will need to be expressed as 8-hour, time-weighted averages (TWAs). One contract might require paint chip analyses to be expressed as milligrams per square centimeter. Another
contract might require the data be expressed as percent by weight.
Other supporting information for the data reported should include any deviations from the standard sampling or analytical methods used. An explanation should be provided stating the reason(s) why changes were made.
The information provided by the report should allow another professional to repeat the sampling and analysis. Assuming the environmental conditions remained the same, similar results should be obtained.
17.1.2 Sampling and analysis plan
The sampling and analysis plan is usually prepared by the sampling organization in consultation with the laboratory. The written plan describes the purpose of the sampling and contains the following information:
9 Standard methods that will be used to collect and analyze the samples
9 How many samples will be collected
9 Sampling locations, or how the locations will be selected in the field
9 Information to be recorded for each sample collected (e.g., sample number, date, time, location, description) 9 Sample handling and shipping procedures, including
chain-of-custody
9 Which laboratory or laboratories will perform the analyses (if applicable)
9 Any special safety and health precautions necessary (e.g., safety glasses, gloves, respirator)
9 How results will be reported
9 Quality control samples to be collected, including type and frequency
It is advisable to develop a separate sampling and analysis plan for each type of sampling performed. While this is not required, it is often less confusing. The length and complexity of each plan depends on the size of the sampling effort and the data to be gathered. The plan to characterize paint in one room prior to a maintenance task may consist of only a few sentences. A plan to measure lead in soil throughout a housing development will likely be quite lengthy.
17.1.2.1 Regulatory sampling requirements Often sampling and analysis is conducted to determine compliance with a federal, state, or local regulation. The EPA regulations at 40 CFR 745.65 have specific criteria for lead- based paint haTards based on lead in dust concentrations and soil lead concentrations. Sampling and analyses conducted for compliance with these requirements must be performed in
accordance with the procedures specified by the regulations.
The regulations will also dictate the qualifications of both the person collecting the samples and the laboratory performing the analyses.
The OSHA lead regulations also mandate certain sampling and analyses be performed. For air samples, personal sampling must be conducted to measure exposures and determine compliance with the action level or permissible exposure limit.
OSHA also does not recognize XRF as adequate to measure lead in paint, which may be disturbed by construction, renovation, or maintenance activities. In many sampling situations the ASTM sampling and analytical methods described later in this chapter are appropriate. For regulatory compliance, the methods required by the regulation(s) should be used.
17.1.2.2 Selection of valid standard methods
Valid standard methods should be used whenever possible.
Standard methods are developed by government agencies and standards organizations. They have been peer reviewed and published. "Valid" standard methods have been tested (validated) for their designed purpose, and over the range of their intended use. Most current standard methods useful for managing lead haTzrds are listen in section 17.2 of this chapter.
17.1.2.3 Quality control
Persons conducting sampling and analysesshould follow recognized quality control procedures for the methods performed. The specific quality control procedures for each sampling effort should be specified in the sampling plan.
Quality control methods followed in the laboratory during the analysis are specified in the standard analytical method employed.
Some common types of quality control samples collected are blank samples, split samples, and field-spiked samples.
Blank samples are submitted to the same conditions as other samples in the field, but do not contain any sample. These are collected, transported and analyzed along with the other samples. The purpose of these samples is to check for systematic contamination of samples by lead in the batch of samples submitted.
Split samples are prepared by separating a sample into two equal parts. If both parts are sent to the same laboratory, it is a check for intralaboratory variability. If the two parts are sent to different laboratories, it is a check for interlaboratory variability. With the assumption the results should be the same (or very similar), split samples provide valuable
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information about the quality of the data produced from the sampling effort.
Field spiked samples are sometimes appropriate for water and soil sampling. This technique involves adding a known amount of lead to a blank sample of the same type of media (i.e., soil or water). The spiked samples are submitted with the other samples for analysis by the laboratory. The percent lead recovered is calculated based on the amount known to be added and the amount found.
Additional quality control samples are prepared in the laboratory. These may include laboratory blanks, recovery samples, and standard addition samples. These results are used by the laboratory to check the quality of the data produced by the analyses.
The results of the quality control samples are reviewed to determine if they are within published ranges for the method(s) employed. For some methods it may be appropriate to correct the results based on the quality control sample findings. If the quality control samples are not in the expected range of acceptance an investigation should be performed to determine why. It will sometimes be necessary to repeat the sampling and/or analyses once the problem is identified.
17.1.2.4 Documentation and chain-of-custody using ASTM Guide D 4840 and Practice E 1864 The ASTM Standard Guide for Sampling Chain-of-Custody Procedures (I)4840) provides information and guidance for maintaining a sample chain-of-custody. It is intended as guidance only. For any given sampling effort the chain-of- custody is the paperwork that demonstrates the integrity of the sample has not been compromised between the time of collection and receipt at the laboratory.
The example chain-of-custody documents in ASTM D 4840 can accommodate over 100 pieces of information. This is unnecessary and often leads to errors due to transcription of voluminous information not needed by the laboratory, and often not desirable. The critical information that must be on the chain-of-custody documentation is as follows:
9 A list of each sample in the shipment
9 Name, affiliation, and signature of the person collecting the samples
9 Date(s) the samples in the shipment were collected and transferred
9 Name, affiliation and signature of each person taking receipt of the sample with date and time received (common carriers excepted)
9 Condition of the sample as received by each recipient
ASTM Standard Practice E 1864 provides general guidance on the quality of documentation and records. Section 11 provides general guidance on instrmnent calibration and the use of field test methods. Sections 12 and 13 provide guidance on the selection of sampling procedures and sample handling techniques.