SAMPLING AND SURVEYING RADIOLOGICAL ENVIRONMENTS - CHAPTER 5 ppt

The sample label is filled out, noting the sampling time and date, sample identification number, sampling depth, analyses to be performed, sampler’s initials, etc.. Consequently, field l

Sample Preparation, Documentation, and

Shipment

After the sample collection procedure is complete, sample containers must be preserved (if required), capped, custody-sealed, and transported along with appro-priate documentation to the on-site or fixed analytical laboratory for analysis Great care should be taken when preparing samples for shipment since an error in this procedure has the potential of invalidating the samples and subsequent data

5.1 SAMPLE PREPARATION

Immediately after a sample bottle has been filled, it must be preserved as specified in the Sampling and Analysis Plan Sample preservation requirements vary, based on the sample matrix and the analyses being performed Radiological analyses run on soil, sediment, or solid waste samples rarely require any sample preservation since the radiological composition and activity levels are not influenced by temper-ature or other factors as the chemical composition is Water or liquid waste samples for radiological analysis are often preserved with nitric acid (HNO3) to prevent isotopes from adhering to the walls of the sample container Enough nitric acid is added to lower the pH to < 2 For chemical analysis, the only preservation typically required for soil or sediment samples is cooling the sample to 4°C For water samples, some analyses only require cooling to 4°C, whereas others also require a chemical preservative such as HNO3, sulfuric acid (H2SO4), hydrochloric acid (HCl),

or sodium hydroxide (NaOH) Enough acid or base is added to the sample bottle either to lower the pH to < 2 or to raise the pH to >10 The laboratory running the analyses will specify which preservative is required for a particular analysis.The chemicals used to preserve a sample must be of analytical grade to avoid the potential for contaminating the sample Cooling samples to 4°C is particularly important for samples to be analyzed for volatile organic compounds since cooling the sample slows the rate of chemical degradation

To avoid any difficulties associated with adding chemical preservatives to sample containers in the field, it is recommended that these preservatives be added to sample bottles in a controlled setting prior to entering the field This alternative reduces the chances of improperly preserving sample bottles or introducing field contaminants into a sample bottle while adding the preservative

The preservative should be transferred from the chemical bottle to the sample container using either a disposable polyethylene pipette or a standard glass pipette

A glass eye dropper with rubber bulb is not recommended since the rubber has a potential of introducing contaminants into the sample

The disposable pipette is made of polyethylene, and should be used only once, and then discarded This pipette is more convenient than the standard glass pipette method and provides the least opportunity for the cross-contamination of samples The standard glass pipette is preferred over the disposable pipette when bottles for volatile organic analysis need to be preserved, since polyethylene has the potential

of providing trace volatile organics to the sample

After a sample container has been filled, a Teflon-lined cap or lid is screwed

on tightly to prevent the container from leaking The sample label is filled out, noting the sampling time and date, sample identification number, sampling depth, analyses to be performed, sampler’s initials, etc (see Section 5.2.5) A custody seal

is then placed over the cap or lid just prior to placing the sample bottle into the sample cooler The custody seal is used to detect any tampering with the sample prior to analysis

5.2 DOCUMENTATION

Accurate documentation is essential for the success of a sampling program It

is only through documentation that a sample can be tied into a particular sampling time, date, location, and depth Consequently, field logbooks must be kept by every member of the field team, and should be used to record information ranging from weather conditions to the time the driller stubbed his right toe To assist the docu-mentation effort, standardized forms are commonly used to outline the information that needs to be collected Some of the more commonly used forms include:

• Scanning instrument quality control check form

• Borehole log forms

• Well completion forms

• Well development forms

• Well purging/sampling forms

• Water level measurement forms

Other documentation needs associated with sample identification and shipment include:

• Sample labels

• Chain-of-custody forms

• Custody seals

• Shipping airbills

In addition to the above documentation requirements, a careful file must be kept

to track important information, such as:

• Field variances

• Equipment shipping invoices

• Sample bottle lot numbers

• Documented purity specifications for preservatives, distilled water, and calibration standards

• Instrument serial numbers

• Copies of shipping paperwork

• Quality assurance nonconformance notices

5.2.1 Field Logbooks

Field logbooks are intended to provide sufficient data and observations to enable participants to reconstruct events that occurred during projects and to refresh the memory of the field personnel if called upon to give testimony during legal pro-ceedings In a legal proceeding, logbooks are admissible as evidence, and conse-quently must be factual, detailed, and objective

Field logbooks must be permanently bound, the pages must be numbered, and all entries must be written with permanent ink, signed, and dated If an error is made

in the logbook, corrections can be made by the person who made the entry A correction is made by crossing out the error with a single line, so as not to obliterate the original entry, and then entering the correct information All corrections must

be initialed and dated

Observations or measurements that are taken in an area where the logbook may

be contaminated can be recorded in a separate bound and numbered logbook before being transferred into the master field notebook All logbooks must be kept on file

as permanent records, even if they are illegible or contain inaccuracies that require

a replacement document

The first page of the logbook should be used as a Table of Contents to facilitate the location of pertinent data As the logbook is being completed, the page numbers where important events can be found should be recorded The very next page should begin recording daily events The first daily event entry should always be the date, followed by a detailed description of the weather conditions All of the following entries should begin with the time that the entry was made Any space remaining

on the last line of the entry should be lined out to prevent additional information being added in the future At the end of the day, any unused space between the last entry and the bottom of the page should be lined out, signed, and dated, to prevent additional entries being made at a later date

To assure that a comprehensive record of all important events is recorded, each team member should keep a daily log The field manager’s logbook should record information at the project level, such as:

• Time when team members, subcontractors, and the client arrive or leave the site;

• Names and company affiliation of all people who visit the site;

• Summary of all discussions and agreements made with team members, subcon-tractors, and the client;

• Summary of all telephone conversations;

• Detailed explanations of any deviations from the sampling and analysis plan, noting who gave the authorization, and what paperwork was completed to document the change;

• Detailed description of any mechanical problem that occurred at the site, noting when and how it occurred, and how it is being addressed;

• Detailed description of any accidents that occurred, noting who received the injury, how it occurred, how serious the injury was, how the person was treated, and who was notified;

• Other general information such as when and how equipment was decontaminated, what boreholes were drilled, and what samples were collected that day.

The team member’s logbook should record information more at the task level Examples of the types of information that should be recorded in these logbooks include:

• Time when radiological surveys began and ended on a particular site;

• Details on the instruments used to collect radiological measurements;

• Results from instrument calibration checks;

• Details on remedial activities performed at the site;

• Radiological measurement data;

• Level of personal protective equipment used at the site;

• Sample collection times for all samples collected;

• Total depth of any boreholes drilled;

• Detailed description of materials used to build monitoring wells, including type of casing material used; screen slot size; length of screen; screened interval; brand name, lot number, and size of sand used for the sand pack; brand name, lot number, and size of bentonite pellets used for the bentonite seal; brand name and lot number

of bentonite powder and cement used for grout; well identification number;

• Details on when, how, and where equipment was decontaminated, and what was done with the wastewater;

• Description of any mechanical problems that occurred at the site, noting when and how it occurred, and how it was addressed;

• Summary of all discussions and agreements made with other team members, subcontractors, and the client;

• Summary of all telephone conversations;

• Detailed description of any accidents that occur, noting who received the injury, how it occurred, how serious the injury was, how the person was treated, and who was notified.

It is essential that field team members record as much information as possible

in their logbooks, since this generates a written record of the project Years after the project is over, these notebooks will be the only means of reconstructing events that occurred With each team member recording information, it is not uncommon for one member to record information that another member missed

5.2.2 Photographic Logbook

A photographic logbook should be used to record all photographs taken at a site This log should record the date, time, subject, frame, roll number (or disk number for a digital camera), and the name of the photographer For “instant photos,” the date, time, subject, and name of the photographer should be recorded directly on the developed picture Clear photographs of field activities can be very useful in reconciling any later discrepancies

5.2.3 Field Sampling Forms

It is recommended that standardized field sampling/measurement forms be used

to assist the sampler in a number of field activities Some commonly used forms are presented in Figures 5.1 through 5.6 Forms are most often used to reduce the amount of documentation required in the field logbook Forms are also effective in reminding the sampler of what information needs to be collected, and they make it more obvious when the necessary information was not collected

When forms are used, they should be permanently bound in a notebook, the pages should be numbered, and all entries must be written with permanent ink If

an error is made in the notebook, corrections can be made by the person who made the entry A correction is made by crossing out the error with a single line so as not

to obliterate the original entry and then entering the correct information All correc-tions must be initialed and dated The person who completed the form should sign and date the form at the bottom of the page It is recommended that the field manager also sign the form to confirm that it is complete and accurate

5.2.4 Identification and Shipping Documentation

The essential documents for sample identification and shipment include the sample label, custody seal, chain-of-custody form, shipping manifest, and shipping airbill Together, these documents allow radioactive samples to be shipped and/or transported to an analytical laboratory under custody If custody seals are broken when the laboratory receives the samples, the assumption must be made that the samples were tampered with during shipment Consequently, the samples may need

to be collected over again When shipping radioactive samples off site, it is essential that 49 CFR 170 through 180 requirements for shipping container inspection and surveying be carefully observed If shipping radioactive samples by air, the require-ments provided in the International Air Transportation Association (IATA), Danger-ous Goods Regulations, must be followed

Before shipment, and upon receipt of a radioactive shipment, a visual inspection

of packages should be performed to ensure that packages are not damaged Prior to shipment, gross alpha and gross beta/gamma measurements should be collected from the outside surfaces of the individual sample containers and the shipping container and the results recorded on the shipping paperwork Care should be taken prior to shipping multiphased radioactive samples, as settling of hot particulate or layering may occur, resulting in an increase in the radiation levels that are measured for the

container The radiation levels should be measured after settling has occurred and the highest value used for preparing the shipment When the shipping container is received by the laboratory, gross alpha and gross beta/gamma measurements should once again be collected from the outside surfaces of the shipping container and should be compared against the readings reported on the shipping papers This practice ensures accountability Any differences should be reconciled prior to accept-ing the sample shipment

Figure 5.1 Example of scanning instrument quality control check form.

Drivers of motor vehicles transporting radioactive samples should have a copy

of their emergency response plan or the emergency response information with them

as required by 49 CFR 172.600

Figure 5.2 Example of a borehole log form used to record borehole lithology.

5.2.5 Sample Labels

The primary objective of the sample label is to link a sample bottle to a sample number, sampling date and time, and analyses to be performed The sample label

in combination with the chain-of-custody form is used to inform the laboratory what the sample is to be analyzed for At a minimum, a sample label should contain the following information (Figure 5.7):

• Sample identification number

• Sampling time and date

Figure 5.3 Example of a well completion form.

• Analyses to be performed

• Preservatives used

• Sampler’s initials

• Name of the company collecting the sample

• Name and address of the laboratory performing the analysis.

To save time in the field, and to avoid the potential for errors, all of the above information should be added to the sample label before going into the field, with the exception of the sampling time and date, and sampler’s initials This information

Figure 5.4 Example of a well development form.

should be added to the label following the capping of the sample bottle, immediately after sample collection, and should reflect the time that sampling began, as opposed

to the time sampling was completed

An effective sample numbering system is a key component of any field sampling program since it serves to tie the sample to its sampling location The problem with using a simple numbering system such as 1, 2, 3, … is that the number tells you nothing regarding the location, depth, or sample media

The number of digits used in a sample numbering scheme should be discussed with the laboratory performing the analyses since it may have limitations on the

Figure 5.5 Example of a well purging and sampling form.