Index > Appendixes >

Appendix F: Glossary of specific terms applied in site characterization, remediation and restoration processes; Part A - M

absorbed dose: A measure of the energy from ionising radiation deposited in a unit mass of any specified material. The unit of absorbed dose is the Gray.

absorption: Process where material in contact with the skin may pass through the pores on the skin’s surface and enter the bloodstream. Identified as a possible route for contaminant entry into the body.

absorption of gamma rays: The process resulting from interaction of gamma quanta (photons) with matter, caused by photoeffect and pair production.

228Ac: actinium-228.

accuracy: Level of agreement between true value and observed value.

accuracy of gamma ray spectrometry analyses: The reliability of analyses in the sense of the relationship of resulting data to the true value of the radioelement concentration.

action level: The numerical value that will cause the decision maker to choose one of the alternative actions. It may be a regulatory threshold standard (e.g., Maximum Contaminant Level for drinking water), a dose- or risk-based concentration level (e.g., DCGL), or a reference-based standard. See investigation level.

activation: Process where a neutron is captured by a nucleus to form a new isotope (often a radionuclide).

activation product: An isotope created by activation.

active flushing: An engineered (artificially enhanced) version of natural flushing, often used to increase the groundwater magnitude and flow velocity.

activity concentration: Terminology used to describe radioactivity levels relative to the mass or volume of the sample matrix (e.g., Bg/kg in soil, Bg/L in water).

activity: See radioactivity.

ADP: Automatic Data Processing.

adsorption: A process somewhat similar to ion exchange whereby molecular contaminants are immobilized onto a solid matrix (sorbed onto the solid surface).

airborne gamma ray spectrometer: A high sensitivity gamma ray spectrometer with the capacity to detect gamma rays, analyse and record energy gamma ray spectra in short (s) time intervals within a flight.

airborne gamma ray survey: A survey carried out using an airborne gamma ray spectrometer installed in an aeroplane.

ALARA (acronym for As Low As Reasonably Achievable): A basic concept of radiation protection which specifies that exposure to ionizing radiation and releases of radioactive materials should be managed to reduce collective doses as far below regulatory limits as is reasonably achievable considering economic, technological, and societal factors, among others. Reducing exposure at a site to ALARA strikes a balance between what is possible through additional planning and management, remediation, and the use of additional resources to achieve a lower collective dose level. A determination of ALARA is a site-specific analysis that is open to interpretation, because it depends on approaches or circumstances that may differ between regulatory agencies. An ALARA recommendation should not be interpreted as a set limit or level.

ALARP: As Low As Reasonably Practicable – a standard for assessing necessary control measures taking into account the practicalities of the task in hand. Note: “reasonably practicable” has a defined legal meaning in the UK. ALARP incorporates this legal meaning as opposed to any other meaning that may be implied from technical publications such as those by the International Commission on Radiological Protection (ICRP).

ALF: Action Levels and Standards Framework.

alluvium: A surface accumulation or near surface deposit of unconsolidated or poorly consolidated gravel, sand, clays or peats that are loosely arranged, unstratified or not cemented together.

alpha (α): The specified maximum probability of a Type I error. In other words, the maximum probability of rejecting the null hypothesis when it is true. Alpha is also referred to as the size of the test. Alpha reflects the amount of evidence the decision maker would like to see before abandoning the null hypothesis.

alpha decay: A form of radioactive decay resulting in the emission of a positively charged particle (a helium nucleus).

alpha particle: A positively charged particle emitted by some radioactive materials undergoing radioactive decay.

alpha radiation: The flux of alpha particles, formed by 2 protons and 2 neutrons.

alpha spectrometry: A sample analysis technique that detects alpha particles emitted from radioisotopes at energies between about 4 and 6 MeV.

alternative hypothesis (Ha): See hypothesis.

AM: action memorandum.

241Am: americium-241.

AMD: Acid Mine Drainage.

Amin: The smallest area of elevated activity identified using the DQO Process that is important to identify.

analytical measurement error: The degree to which a laboratory is able to measure a constituent in a given sample within its actual value.

annual effective dose: A measure of the energy deposited by radiation in organs and tissue per year – measures the biological effects of radiation to humans.

anomaly: a variation in radiation level exceeding those fluctuations normally expected because of the statistical nature of radioactive decay.

anthropogenic radionuclides: Artificially produce radionuclides, by means of activation or nuclear fission.

Approved Dosimetry Service (ADS): A dosimetry service approved by HSE (or a body specified by HSE) for measuring, assessing and recording radiological doses to workers. The aim of approval is to ensure, as far as is possible, that doses are assessed on the basis of accepted national standards.

ARD: Acid Rock Drainage.

area: A general term referring to any portion of a site, up to and including the entire site.
area factor (Am): A factor used to adjust DCGLW to estimate DCGLEMC and the minimum detectable concentration for scanning surveys in Class 1 survey units – DCGLEMC = DCGLW •Am. Am is the magnitude by which the residual radioactivity in a small area of elevated activity can exceed the DCGLW while maintaining compliance with the release criterion. Examples of area factors are provided in Section 5 of this manual.

area of elevated activity: An area over which residual radioactivity exceeds a specified value DCGLEMC.

arithmetic mean: The average value obtained when the sum of individual values is divided by the number of values.

arithmetic standard deviation: A statistic used to quantify the variability of a set of data. It is calculated in the following manner: 1) subtracting the arithmetic mean from each data value individually, 2) squaring the differences, 3) summing the squares of the differences, 4) dividing the sum of the squared differences by the total number of data values less one, and 5) taking the square root of the quotient. The calculation process produces the Root Mean Square Deviation (RMSD).

ASL: Analytical Support Level.

assessment: The evaluation process used to measure the performance or effectiveness of a system and its elements. As used in MARSSIM, assessment is an all-inclusive term used to denote any of the following: audit, performance evaluation, management systems review, peer review, inspection, or surveillance.

atmospheric fallout: Widespread dispersion of radionuclides. Normally refers to the effects of nuclear weapons testing or events with global impact such as Chernobyl.

ATP: Adenosine Triphosphate.

attainment objectives: Objectives that specify the design and scope of the sampling study including the radio-nuclides to be tested, the cleanup standards to be attained, the measure or parameter to be compared to the cleanup standard, and the Type I and Type II error rates for the selected statistical tests.

ATV: All-Terrain Vehicle.

audit (quality): A systematic and independent examination to determine whether quality activities and related results comply with planned arrangements and whether these arrangements are implemented effectively and are suitable to achieve objectives.

available (or existing) technology: A technology that is fully proven in routine commercial use and for which sufficient performance and cost information are available.

averaging volume: The volume of waste over which the activity concentration is measured and averaged to give an average activity concentration for waste sentencing purposes.

background radiation: Radiation from cosmic sources, naturally occurring radioactive material, including radon (except as a decay product of source or special nuclear material), and global fallout as it exists in the environment from the testing of nuclear explosive devices or from nuclear accidents like Chernobyl which contribute to background radiation and are not under the control of the cognizant organization. Background radiation does not include radiation from source, by-product, or special nuclear materials regulated by the cognizant Federal or State agency. Different definitions may exist for this term. The definition provided in regulations or regulatory program being used for a site release should always be used if it differs from the definition provided here.

background reference area: See reference area.

Becquerel (Bq): The International System (SI) unit of activity equal to one nuclear transformation (disintegration) per second. 1 Bq = 2.7×10-11 Curies (Ci) = 27.03 picocuries (pCi).

beta (β): The probability of a Type II error, i.e., the probability of accepting the null hypothesis when it is false. The complement of beta (1-β) is referred to as the power of the test.

beta decay: A form of radioactive decay resulting in the emission of an electron or positron.
beta particle: An electron emitted from the nucleus during radioactive decay.

beta radiation: The flux of beta particles, formed by electrons.

bias: The systematic or persistent distortion of a measurement process which causes errors in one direction (i.e., the expected sample measurement is different from the sample’s true value).

biased sample or measurement: See judgement measurement.

bio-barrier: A low permeability barrier which employs the growth of bacteria to block the pores in a geological formation, thereby retarding fluid flow.

BOD: Biological Oxygen Demand.

BPEO: Best Practicable Environmental Option.

Bq: Becquerel – a unit of radioactivity (one nuclear transformation per second).

BWR: Boiling Water Reactor.

by-product material: Any radioactive material (except special nuclear material) yielded in or made radioactive by exposure to the radiation incident to the process of producing or utilizing special nuclear material.

CA: Chloroethane.

CAHs: Chlorinated Aliphatic Hydrocarbons.

calibration: The process by which the response of a radiometric instrument is related to sources of known activity or other defined radioactivity quantities. Calibration of radiometric instruments implies the estimation of instrument sensitivities and other constants.

calibration pads: Concrete cylindrical or rectangular pads, enriched individually by radioelements of interest – usually K, U and Th.

CANDU: Canada Deuterium Uranium (pressurized heavy water reactor).

car-borne gamma ray spectrometer: High sensitivity gamma ray spectrometer mounted in a motor vehicle for the detection of gamma-radiation over short (s) time intervals.

CBO: community based organisation.

CD: compact disc.

CDE (Committed Dose Equivalent): The dose equivalent calculated to be received by a tissue or organ over a 50-year period after the intake into the body. It dose not include contributions from radiation sources external to the body. CDE is expressed in units of Sv or rem.

CEDE (Committed Effective Dose Equivalent): The sum of the committed dose equivalent to various tissues in the body, each multiplied by the appropriate weighting factor (Wt). CEDE is expressed in units of Sv or rem. See TEDE.

CF: Concentration Factor for a radionuclide between different environmental compartments, for example soil solution and plants (ratio of Bq/g plant to Bq/mL water or soil solution).

CG: Coordination Group.

chain of custody: An unbroken trail of accountability that ensures the physical security of samples, data, and records.

characterization survey: A type of survey that includes facility or site sampling, monitoring, and analysis activities to determine the extent and nature of contamination. Characterization surveys provide the basis for acquiring necessary technical information to develop, analyze, and select appropriate cleanup techniques.

CLARC: Cleanup Levels And Risk Calculation.

class 1 area: An area that is projected to require a Class 1 final status survey.

class 1 survey: A type of final status survey that applies to areas with the highest potential for contamination, and meet the following criteria: (1) impacted; (2) potential for delivering a dose above the release criterion; (3) potential for small areas of elevated activity; and (4) insufficient evidence to support reclassification as Class 2 or Class 3.

class 2 area: An area that is projected to require a Class 2 final status survey.

class 2 survey: A type of final status survey that applies to areas that meet the following criteria: (1) impacted; (2) low potential for delivering a dose above the release criterion; and (3) little or no potential for small areas of elevated activity.

class 3 area: An area that is projected to require a Class 3 final status survey.

class 3 survey: A type of final status survey that applies to areas that meet the following criteria: (1) impacted; (2) little or no potential for delivering a dose above the release criterion; and (3) little or no potential for small areas of elevated activity.

class I survey area: A type of final status survey that applies to areas with the highest potential for contamination and that meet the following criteria: (1) impacted, (2) potential for delivering a dose above the release criterion, (3) potential for small areas of elevated activity, and (4) insufficient evidence to support classification as Class 2 or Class 3. Available on-line here.

class II survey area: A type of final status survey that applies to areas that meet the following criteria: (1) impacted, (2) low potential for delivering a dose above the release criterion, and (3) little or no potential for small areas of elevated activity. Available on-line here.

class III survey area: A type of final status survey that applies to areas meeting the following criteria: (1) impacted, (2) little or no potential of delivering a dose above the release criterion, and (3) little or no potential for small areas of elevated activity. Available on-line here.

classification: The act or result of separating areas or survey units into one of three designated classes: Class 1 area, Class 2 area, or Class 3 area.

classified worker: A category of worker defined under the Ionising Radiations Regulations 1999. Any person who, during the course of their work, is likely to receive an annual effective dose in excess of 6 mSv or three-tenths of the appropriate dose limit should be a classified worker.

clastic dyke: Geologic formation which can facilitate vertical transport of contaminants (preferential pathway).

clean-up: Actions taken to deal with a release or threatened release of hazardous substances that could affect public health or the environment. The term is often used broadly to describe various Superfund response actions or phases of remedial responses, such as remedial investigation/ feasibility study. Cleanup is sometimes used interchangeably with the terms remedial action, response action, or corrective action.

clean-up standard: A numerical limit set by a regulatory agency as a requirement for releasing a site after cleanup. See release criterion.

clean-up (survey) unit:) A geographical area of specified size and shape defined for the purpose of survey design and compliance testing.

cm: centimetre.

cm2: square centimetre.

60Co: cobalt-60.

COC: contaminant of concern.

coefficient of variation: A unitless measure that allows the comparison of dispersion across several sets of data. It is often used in environmental applications because variability (expressed as a standard deviation) is often proportional to the mean. See relative standard deviation.

collimating shield: A window-like device made of a material that is impenetrable to gamma rays, such as lead, that can be attached to a scintillator to decrease the size of the detection field.

comparability: The degree to which one set of measurement data agrees with another for similar samples and sampling conditions; it is an overall indicator of data quality that combines accuracy, precision, and representativeness.

completeness: A measure of the amount of valid data obtained from a measurement system compared to the amount that was expected to be obtained under correct, normal conditions.

composite sample: A sample formed by collecting several samples and combining them (or selected portions of them) into a new sample which is then thoroughly mixed.

Compton continuum: That part of the gamma energy spectrum formed by photons that have lost part of their original energies through Compton scattering.

Compton scattering: The interaction of a photon with an orbit electron of an atom, in which the photon loses part of its energy and changes its direction.

conceptual model: A textual or schematic hypothesis of the sources and nature of contamination on a site, the pathways and migration mechanisms by which it may be transported, and the receptors that may be affected.

conceptual site model: A compilation of pertinent information about a site, historical land use, waste disposal records, analytical data sets, etc., that helps investigators to identify existing data gaps. The conceptual site model supports the development of data collection strategies that target those data gaps.

cone penetrometer technologies: Widely used in both federal and private sector cleanups, CPTs are a type of direct-push technology. Instead of producing a borehole as with traditional drilling equipment, a hydraulic ram mounted onto a 20- to 40-ton truck is used to drive a narrow steel cone (e.g., 1.75 in) with attached geotechnical sensors and analytical detectors directly into the ground, saving time and eliminating the potential need for hazardous waste disposal.

confidence interval: A range of values for which there is a specified probability (e.g., 80%, 90%, 95%) that this set contains the true value of an estimated parameter.

confirmatory survey: A type of survey that includes limited independent (third-party) measurements, sampling, and analyses to verify the findings of a final status survey.

consensus standard: A standard established by a group representing a cross section of a particular industry or trade, or a part thereof.

constituent: A chemical species present in a system; often called a component, although the term component has a more restricted meaning in physical chemistry.

contaminant: An undesirable concentration or quantity of a substance, or activity concentration of a radionuclide, present in water, atmosphere or soil.

contaminated land: Any land on or under which radioactive or non-radioactive contaminants are suspected to be present at concentration levels above the natural and artificial background concentration levels that are typical of the location of the site. This is not the same as the statutory definition in Part IIA of the Environmental Protection Act, 1990 which defines the presence of contamination by the possibility of significant harm or the pollution of controlled waters.

contamination: The presence of residual radioactivity in excess of levels which are acceptable for release of a site or facility for unrestricted use.

control chart: A graphic representation of a process, showing plotted values of some statistic gathered from that characteristic, and one or two control limits. It has two basic uses: 1) as a judgement to determine if a process was in control, and 2) as an aid in achieving and maintaining statistical control.

controlled area: Any area where the annual effective dose to persons working there is likely to exceed 6 mSv or three-tenths of the appropriate dose limit.

controlled waste: Defined for the purposes of the Environmental Protection Act 1990 as comprising household, commercial and industrial waste. Excludes certain categories of waste, such as radioactive waste.

controlled waters: Defined in Part III (Section 104) of the Water Resources Act 1991, this embraces territorial and coastal waters, inland fresh waters, and groundwaters.
core sample: A soil sample taken by core drilling.

corrective action: An action taken to eliminate the causes of an existing non-conformance, deficiency, or other undesirable situation in order to prevent recurrence.

cosmic radiation: The component of natural radiation formed by high energy particles and photons coming from outer space. Intensity of cosmic radiation increases with altitude.

cosmogenic radionuclides: Radionuclides produced by the interaction of cosmic rays with terrestrial matter (e.g., in the atmosphere).

count rate: The response of a radiometric instrument to detected radiation, given in counts per unit time.

counting time: Preselected time for a radiometric instrument to accumulate counts as a measure of radiation.

counts: Recorded response of a radiometric instrument to radiation sources. The response is due to either a detected particle or photon of energy.

cpm: counts per minute.

CPTs: Cone Penetrometer Technologies.

CPU: Central Processing Unit.

criterion: See release criterion.

critical group: The group of individuals reasonably expected to receive the greatest exposure to residual radioactivity for any applicable set of circumstances.

critical level (LC): A fixed value of the test statistic corresponding to a given probability level, as determined from the sampling distribution of the test statistic. LC is the level at which there is a statistical probability (with a predetermined confidence) of correctly identifying a background value as “greater than background.”

critical value: The value of a statistic (t) corresponding to a given significance level as determined from its sampling distribution; e.g., if Pr ( t > t0) = 0.05, t0 is the critical value of t at the 5 percent level.

cross-contamination: A process whereby, during a series of intrusive investigations or within a single investigation, contaminated material from one area comes into contact with material from another area, thereby potentially affecting the results of any analyses being carried out.

137Cs: cesium-137.

CSM: Conceptual Site Model.

CT: Carbon tetrachloride.

curie (Ci): The customary unit of radioactivity. One curie (Ci) is equal to 37 billion disintegrations per second (3.7 × 1010 dps = 3.7 × 1010 Bq), which is approximately equal to the decay rate of one gram of 226Ra. Fractions of a curie, e.g. picocurie (pCi) or 10-12 Ci and microcurie (μCi) or 10-6 Ci, are levels typically encountered in decommissioning.

cut-off wall: A vertical barrier installed to prevent the horizontal migration of groundwater.

cyclotron: A device used to impart high energy to charged particles, of atomic weight one or greater, which can be used to initiate nuclear transformations upon collision with a suitable target.

D: The true, but unknown, value of the difference between the mean concentration of residual radioactivity in the survey unit and the reference area.

D&D: Decommissioning and Decontamination.

Data Life Cycle (DLF): The process of planning the survey, implementing the survey plan, and assessing the survey results prior to making a decision is called the Data Life Cycle.

Data Quality Assessment (DQA): The scientific and statistical evaluation of data to determine if the data are of the right type, quality, and quantity to support their intended use.

Data Quality Indicators (DQI): Measurable attributes of the attainment of the necessary quality for a particular decision. Data quality indicators include precision, bias, completeness, representativeness, reproducibility, comparability, and statistical confidence.

Data Quality Objectives (DQOs): Qualitative and quantitative statements derived from the DQO process that clarify study technical and quality objectives, define the appropriate type of data, and specify tolerable levels of potential decision errors that will be used as the basis for establishing the quality and quantity of data needed to support decisions.

Data Quality Objectives Process: A systematic strategic planning tool based on the scientific method that identifies and defines the type, quality, and quantity of data needed to satisfy a specified use. The key elements of the process include:

  • Concisely defining the problem;
  • Identifying the decision to be made;
  • Identifying the inputs to that decision;
  • Defining the boundaries of the study;
  • Developing the decision rule;
  • Specifying tolerate limits on potential decision errors;
  • Selecting the most resource efficient data collection design.

DQOs are the qualitative and quantitative outputs from the DQO process. The DQO process was developed originally by the U.S. Environmental Protection Agency, but has been adapted for use by other organizations to meet their specific planning requirement. See also graded approach.

data usability: The process of ensuring or determining whether the quality of the data produced meets the intended use of the data.

daughter nuclide: See decay product.

daughter products: Radioelements formed in a disintegration series from a mother element.

DCA: Dichloroethane.

DCE: Dichloroethene.

DCF: Dose Conversion Factor.

DCGL: See Derived Concentration Guideline Level

DCGLEMC: derived concentration guideline level: elevated measurement criterion.

DCGLW: derived concentration guideline level: Wilcoxon Rank Sum Test.

dead time: The time required for a detector or a radiometric instrument to generate and process a signal (electrical signal) as a response to detected nuclear particle. During this time the instrument is insensitive to other incident particles or photons.

decay: The decrease in the amount of a radionuclide due to the spontaneous emission of atomic particles from the nucleus.

decay chain: A series of radionuclides, each of which decays into the next radionuclide in the series until a stable nuclide is reached.

decay constant, λ: For a particular radionuclide, λ = dP/dt, where dP is the probability of a given nucleus undergoing a spontaneous nuclear transition in the time interval dt.

decay product: The nuclide produced following a radioactive decay. Also called a daughter nuclide.

decision maker: The person, team, board, or committee responsible for the final decision regarding disposition of the survey unit.

decision rule: A statement that describes a logical basis for choosing among alternative actions.
decommission: To remove a facility or site safely from service and reduce residual radioactivity to a level that permits release of the property and termination of the license and other authorization for site operation.

decommissioning: The process of removing a facility or site from operation, followed by decontamination, and license termination (or termination of authorization for operation) if appropriate. The objective of decommissioning is to reduce the residual radioactivity in structures, materials, soils, groundwater, and other media at the site so that the concentration of each radionuclide contaminant that contributes to residual radioactivity is indistinguishable from the background radiation concentration for that radionuclide.

decontamination: The removal of radiological contaminants from, or their neutralization on, a person, object or area to within levels established by governing regulatory agencies. Decontamination is sometimes used interchangeably with remediation, remedial action, and cleanup.

deconvolution of a spectrum: The process of decomposition of an energy spectrum to spectral components corresponding to that from individual contributing sources.

Defence site: In this guidance, non-nuclear sites that have been or are being used for defence activities and for which a change of use and/or ownership is planned. Nuclear sites that are operated for Ministry of Defence (MoD) by contractors and that are licensed and regulated by HSE under the Nuclear Installations Act are nuclear-licensed sites.

delicensing: The process of releasing a nuclear-licensed site from regulation under the Nuclear Installations Act and of releasing the operator from his period of responsibility for any nuclear liability.

delta (δ): The amount that the distribution of measurements for a survey unit is shifted to the right of the distribution of measurements of the reference area.

delta (Δ): The width of the gray region. Δ divided by σ, the arithmetic standard deviation of the measurements, is the relative shift expressed in multiples of standard deviations. See relative shift, gray region.

dense non-aqueous phase liquids: Chemicals that are denser than and immiscible with water upon environmental release.

Derived Concentration Guideline Level (DCGL): A derived, radionuclide-specific activity concentration within a survey unit corresponding to the release criterion. The DCGL is based on the spatial distribution of the contaminant and hence is derived differently for the nonparametric statistical test (DCGLW) and the Elevated Measurement Comparison (DCGLEMC). DCGLs are derived from activity/dose relationships through various exposure pathway scenarios.
The DCGL can also be used for non-radiological parameters e.g. temperature, relative humidity, concentration of volatile-organic-compounds, concentration of chemical compounds etc.

design specification process: The process of determining the sampling and analysis procedures that are needed to demonstrate that the attainment objectives are achieved.

detection efficiency: Probability that an incident particle or photon will interact with the detector – the ratio of registered counts to the number of incident particles.

detection limit: The net response level that can be expected to be seen with a detector with a fixed level of certainty.

detection sensitivity: The minimum level of ability to identify the presence of radiation or radioactivity.

detector: A sensitive sensor having the capacity to register ionizing radiation directly or to transform the energy of incident nuclear particles to electrical quantities.

dH: Deutsche Harte = one degree dH = one gram CaO/100 Liter H2O.

differential gamma ray spectrometer: Radiometric instrument that registers gamma rays of energies within defined lower and upper limits (in energy channels).

direct measurement: Radioactivity measurement obtained by placing the detector near the surface or media being surveyed. An indication of the resulting radioactivity level is read out directly.

discharge: Any emission of a contaminant into the environment.

displacement barrier: A barrier constructed by forcing the barrier material into the ground without any associated excavation.

distribution coefficient (Kd): The ratio of elemental (i.e., radionuclide) concentration in soil to that in water in a soil-water system at equilibrium. Kd is generally measured in terms of gram weights of soil and volumes of water (g/cm3 or g/ml).

DLF: See Data Life Cycle.

DNAPL: Dense Non-Aqueous Phase Liquid.

dose: A measure of the energy deposits by radiation in a target.

dose commitment: The dose that an organ or tissue would receive during a specified period of time (e.g., 50 or 70 years) as a result of intake (as by ingestion or inhalation) of one or more radio-nuclides from a given release.

dose constraint: A target maximum individual dose set by an employer or Radiation Protection Adviser for any project involving the use of ionising radiations. The target is set on the basis of what can be achieved by best practice and helps to keep doses ALARP.

dose equivalent (dose): A quantity that expresses all radiations on a common scale for calculating the effective absorbed dose. This quantity is the product of absorbed dose (rads) multiplied by a quality factor and any other modifying factors. Dose is measured in Sv or rem.

dose rate: The ratio of the dose deposited by radiation in a target to the exposure time.
double-blind measurement: Measurements that cannot be distinguished from routine measurements by the individual performing the measurement. See non-blind measurement and single-blind measurement.

dpm: Disintegrations per minute.

DQA: See Data Quality Assessment.

DQI: Data Quality Indicator.

DQOs: See Data Quality Objectives.

DVS: Dynamic Verification Study.

EDE: Effective Dose Equivalent.

EE/CA: Engineering Evaluation/Cost Analysis.

effective dose: The quantity E, defined as a summation of the tissue equivalent doses (HT), each multiplied by the appropriate tissue weighting factor (wT). E = ƩwTHT.

effective probe area: The physical probe area corrected for the amount of the probe area covered by a protective screen.

EIA: Environmental Impact Assessment.

electro-kinetics: The use of an electrical field to remove contaminants from the groundwater or from soil.

electron-hole pairs: In a semiconductor crystal, a gamma ray can excite an electron up from ist valence band to a higher energy level. The electron leaves behind a .hole. that acts like a positively charged particle. The electron-hole pairs are held together with their opposite charges and can carry electric current throughout the crystal.

electrowinning: Concentration of metals from a pregnant solution using electrolysis techniques.
elevated area: See area of elevated activity.

elevated measurement: A measurement that exceeds a specified value DCGLEMC.
Elevated Measurement Comparison (EMC): This comparison is used in conjunction with the Wilcoxon test to determine if there are any measurements that exceed a specified value _DCGLEMC.

emerging technology: Those technologies that require additional laboratory or pilot-scale testing to document the technical viability of the process.

EMC: elevated measurement criterion.

EML: Environmental Measurements Laboratory.

EMS: Excavation Monitoring System.

energy calibration: The process of establishing the relationship between energy of recorded gamma rays, and the channel number of a multichannel gamma ray spectrometer.

energy gamma ray spectrum: A graphical presentation of the energies of gamma rays against their frequency (counts per channel). Peaks in the spectrum indicate radionuclide emission lines.

energy resolution: Parameter describing the ability of detector to distinguish gamma ray energies.

energy threshold: An energy below which all particles/photons are ignored.

energy window: A defined energy interval of the gamma ray spectrum. Energy window implies several energy channels.

environment: The environment includes, but is not limited to, people’s property (e.g. houses and land), existing and potential resources (e.g. groundwater, water quality, air quality) and natural ecosystems. In this guidance, people are regarded separately from the environment. The distinction is made for consistency with health and safety, and radiological protection, terminology.

envisageable options: All the options that would be effective for managing the contaminated land.

equivalent dose: The sum of the corrected doses (see quality factor) for each type of radiation. Takes into account the different amounts of damage done by different radioactive decay types. The unit of equivalent dose is the Sievert.

equivalent uranium, equivalent thorium: The concentration of uranium/thorium estimated by gamma ray spectrometry under the assumption that the U and Th decay series are in secular equilibrium.

excavated barrier: A barrier constructed by removing soil material and replacing it with the a desired barrier material.

exempt waste: Radioactive waste that is exempt from some or all of the requirements of the Radioactive Substances Act 1993. Such wastes are defined in Exemption Orders made under the Act. See also SoLA.

exemption orders: Subsidiary legislation, operating under the Radioactive Substances Act 1993, that “exempts” certain materials and forms up to prescribed activity concentrations from some or all of the requirements of the Act.

exposure pathway: The route by which radioactivity travels through the environment to eventually cause radiation exposure to a person or group.

exposure rate: The amount of ionization produced per unit time in air by X-rays or gamma rays. The unit of exposure rate is Roentgens/hour (R/h); for decommissioning activities the typical units are microRoentgens per hour (μR/h), i.e., 10-6 R/h.

ex-situ technology: A process applied external to the contaminated region, above ground.
external radiation: Radiation from a source outside the body.

extraction: Removal (extraction) of groundwater via pumping.

fallout: Fallout, nuclear fallout, man-made radioactive isotopes deposited on the earth surface.
false negative decision error: The error that occurs when the null hypothesis (H0) is not rejected when it is false. For example, the false negative decision error occurs when the decision maker concludes that the waste is hazardous when it truly is not hazardous. A statistician usually refers to a false negative error as a Type II decision error. The measure of the size of this error is called beta, and is also known as the complement of the power of a hypothesis test.

false positive decision error: A false positive decision error occurs when the null hypothesis (H0) is rejected when it is true. Consider an example where the decision maker presumes that a certain waste is hazardous (i.e., the null hypothesis or baseline condition is “the waste is hazardous”). If the decision maker concludes that there is insufficient evidence to classify the waste as hazardous when it truly is hazardous, the decision maker would make a false positive decision error. A statistician usually refers to the false positive error as a Type I decision error. The measure of the size of this error is called alpha, the level of significance, or the size of the critical region.

FID: Flame Ionization Detector.

FIDLER: Field Instrument for Detecting Low Energy Radiation.

field sampling plan: As defined for Superfund in the Code of Federal Regulations 40 CFR 300.430, a document which describes the number, type, and location of samples and the type of analyses to be performed. It is part of the Sampling and Analysis Plan.

final remediation levels: Media-specific cleanup goals that are indicative of a site that requires no further remediation.

final status survey: Measurements and sampling to describe the radiological conditions of a site, following completion of decontamination activities (if any) in preparation for release.

fingerprint (radiological): A mixture of radioactive isotopes that distinguish a particular emission.

fission product: A nuclide produced as a result of nuclear fission.

fluence: A measure of the strength of a radiation field.

fluence rate: A fundamental parameter for assessing the level of radiation at a measurement site. In the case of in situ spectrometric measurements, a calibrated detector provides a measure of the fluence rate of primary photons at specific energies that are characteristic of a particular radionuclide.

FRL: Final Remediation Levels.

ft: foot.

funnel and gate: A variation of a reactive barrier wherein low permeability barriers are employed to channel contaminated groundwater through a reactive barrier of treatment zone.

FUSRAP: Formerly Utilized Sites Remedial Action Program.

future: The period over which the potential effects of the contaminated land need to be considered when evaluating the options that may be applied to it. Many contaminants have long half-lives in the environment, and so it may be necessary to consider hundreds of years or more.
future use: The range of uses to which the contaminated land will be able to be put after the selected option has been implemented successfully. The range of future uses may be restricted to reduce the potential hazards associated with residual contamination. Alternatively, the site may be made available for any future use, in which case lower levels of residual concentrations of contaminants are likely to be required.

g: gram.

gamma (γ) radiation: Penetrating high-energy, short-wavelength electromagnetic radiation (similar to X-rays) emitted during radioactive decay. Gamma rays are very penetrating and require dense materials (such as lead or steel) for shielding.

gamma ray: Hyphenated when used as an adjective (eg. gamma ray spectrometer).

gamma rays: Photons of energy that posses neither charge nor mass. Electromagnetic radiation with a frequency of about 3×1019Hz.

gamma ray spectrometry: Radiometric method based on the proportionality between energy of gamma quanta deposited in the detector and pulse amplitudes at the output of the detector, that enables the qualitative and quantitative analyses of gamma ray emitting sources.

gamma spectrometry: See gamma ray spectrometry.

gamma total count measurements: Measurement of gamma radiation with instruments responding to gamma rays of all energies.

ganglion: A globule of a substance.

gas-filled detector: Radiation detector consisting of a tube filled with ionisable gas. When the gas is ionised by radiation, the ions are detected by electrodes.

GCR: Gas Cooled Reactor.

geometric correction: A correction applied to instrument sensitivities estimated from calibrations using calibration pads of limited horizontal and vertical dimensions.

geophysics: The science of detecting geological structure and buried objects using a variety of (normally non-intrusive) investigative techniques.

geotechnical testing: Determination of the physical properties of soil/rock.

GIS: Geographic Information System.

global positioning systems: Using satellites in orbit over the earth, a GPS unit can identify a person’s location using built-in internal triangulation calculations. With three satellites in view, latitude and longitude can be calculated; with four satellites in view, latitude, longitude, and elevation can be calculated. Differentially corrected GPS units have an error of approximately 2 m horizontally and tens of meters vertically, while civil-survey grade systems can provide sub-centimetre accuracy in all three dimensions.

GPERS-II: Global Positioning Environmental Radiological Surveyor System.

GPS: Global Positioning System.

graded approach: The process of basing the level of application of managerial controls applied to an item or work according to the intended use of the results and the degree of confidence needed in the quality of the results. See data quality objectives process.

gradient, hydrological: The rate of change in total hydraulic head per unit distance of flow in a given direction.

gradient manipulation: See active flushing.

Gray (Gy): SI unit of kerma and absorbed dose, equal to 1 J/kg.

gray region: A quantitative statistical value that expresses the degree of the variability associated or expected with measurements of the radioactivity at a site and captures the range of values over which radiological measurements are expected to vary. The upper bound of the gray region is defined as the DCGLw. The lower bound of the gray region (LBGR) is set so that the gray region spans a range equal to between one and three times the known or estimated value of the standard deviation (σ) of the measurements.

grid: A network of parallel horizontal and vertical lines forming squares on a map that may be overlaid on a property parcel for the purpose of identification of exact locations. See reference coordinate system.

grid block: A square defined by two adjacent vertical and two adjacent horizontal reference grid lines.

gridding: The interpolation of irregularly spaced data onto a mesh at regularly spaced intervals.

gross activity: The total activity measured from a dry sample.

groundwater: All water that is below the surface of the ground in the saturation zone and is in direct contact with the ground or subsoil.

half-life (t1/2): The time required for one-half of the atoms of a particular radionuclide present to disintegrate.

harm: Adverse effect on the health of living organisms, or other interference with ecological systems of which they form a part, and, in the case of humans, including property.

hazard: The potential for harm posed by a contaminant or circumstance, taking no account of the likelihood of exposure.

hazardous: Waste and material that because of their quantity, concentration and/or physical, chemical or infectious characteristics may pose a substantial potential threat to human health or the environment when improperly handled, treated, stored or disposed of, or otherwise mismanaged.

HEAST: Health Effects Assessment Summary Tables.

hectare: A unit of area, equivalent to 10.000 m2.

height correction: The correction of airborne gamma ray spectrometric data for variations in the height of the survey aircraft above the ground.

HEPA filtration: High Efficiency Particulate Air filtration.

heterogeneous: Material with areas of different composition within its volume.

Historical Site Assessment (HSA): A detailed investigation to collect existing information, primarily historical, on a site and its surroundings.

HLW: High Level Waste.

HM: Heavy Metal.

HMX: High Melting (point) eXplosive (also known as octogen and cyclotetramethylene- tetranitramine).

hold point: Exposure limit specified for a particular project, which cannot be exceeded without re-assessment of working practices, including any PPE and RPE requirements.

homogeneous: Material of uniform composition throughout its volume.

homogenized sample: A sample that has been thoroughly mixed so that the concentration of constituents in subsequent subsamples would be equivalently distributed.

hot measurement: See elevated measurement.

hot spot: See area of elevated activity.

HPGe: High Purity Germanium.

HPGe detectors: A real-time instrumentation technology used to detect gamma rays at low activity levels or when many nuclides are present in a sample. This detector produces electron hole pairs upon the photo-ionization of the germanium crystal by high-energy gamma rays.

hr: hour.

HSA: Historical Site Assessment.

HSE: Health and Safety Executive.

HSP: Health and Safety Plan.

HSRAM: Hanford Site Risk Assessment Methodology.

HWGC: Heavy Water Gas Cooled reactor.

hydraulic containment: Containment achieved through the manipulation by hydraulic means of the groundwater flow around a particular region of contamination in order to prevent further migration or movement of the contaminants.

hypothesis: An assumption about a property or characteristic of a set of data under study. The goal of statistical inference is to decide which of two complementary hypotheses is likely to be true. The null hypothesis (H0) describes what is assumed to be the true state of nature and the alternative hypothesis (Ha) describes the opposite situation.

IAEA: International Atomic Energy Agency.

IC: Institutional Control.

ICRP: International Commission on Radiologic Protection.

ILCR: Incremental Lifetime Cancer Risk.

ILW: Intermediate Level Waste.

impacted area: Any area that is not classified as non-impacted. Areas with a reasonable possibility of containing residual radioactivity in excess of natural background or fallout levels.

in: inch.

in situ sample: Measurements of a constituent taken directly in the field.

independent assessment: An assessment performed by a qualified individual, group, or organization that is not part of the organization directly performing and accountable for the work being assessed.

indistinguishable from background: The term indistinguishable from background means that the detectable concentration distribution of a radio-nuclide is not statistically different from the background concentration distribution of that radionuclide in the vicinity of the site or, in the case of structures, in similar materials using adequate measurement technology, survey, and statistical techniques.

industrial process: Term used very broadly in the present report to denote any human activity involving the application of technology, for example, mining, processing and drinking water treatment.

inferential uncertainty: The relationship between the measured parameters and the contaminants of concern.

infiltration rate: The rate at which a quantity of a hazardous substance moves from one environmental medium to another – e.g., the rate at which a quantity of a radio-nuclide moves from a source into and through a volume of soil or solution.

infinite radiation source: A source of gamma radiation represented by an infinite half-space with homogeneous concentration of a radionuclide or radionuclides.

ingestion: Contaminant entering the stomach and gastrointestinal tract through eating contaminated food or hand to mouth contact.

inhalation: Breathing contaminant (e.g. particulate material, vapour, gas) in through the mouth or nose.

injection: Contaminant entering the body tissue and blood stream directly through cuts and abrasions.

innovative technology: A treatment technology for which cost or performance information is incomplete, thus hindering routine use at hazardous waste sites. An innovative technology may require additional full-scale field testing before it is considered proven and ready for commercialization and routine use.

in-situ technology: A process applied in place (within the ground or contaminated region).

inspection: An activity such as measuring, examining, testing, or gauging one or more characteristics of an entity and comparing the results with specified requirements in order to establish whether conformance is achieved for each characteristic.

internal radiation: The term describing the radiation field and absorbed doses from internal sources in the human body.

internal radiation dose: Dose received internally to the body via inhalation, absorption, ingestion or injection routes.

intervention: Any action intended to reduce or avert exposure or the likelihood of exposure to sources which are not part of a controlled practice or which are out of control as a consequence of an accident.

inventory: Total residual quantity of formerly licensed radioactive material at a site.

investigation level: A derived media-specific, radio-nuclide-specific concentration or activity level of radioactivity that: 1) is based on the release criterion, and 2) triggers a response, such as further investigation or cleanup, if exceeded. See action level.

ion exchange: A usually reversible exchange of one ion with another, either on a solid surface , or within a lattice. A commonly used method for treatment of liquid waste.

ionising radiation: Any form of radiation that is capable of ionising matter. Typically this ionisation takes the form of displacing an electron from an atom.

ionization: The interaction of nuclear radiation with matter resulting in the generation of charged particles.

IRA: Interim Remedial Action

irradiation: The process of subjecting an entity to radiation.

ISO: International Organization for Standardization.

isopleth: A line drawn through points on a graph or plot at which a given quantity has the same numerical value or occurs with the same frequency.

ITRC: Interstate Technology & Regulatory Council (US).

judgment measurement: Measurements performed at locations selected using professional judgment based on unusual appearance, location relative to known contaminated areas, high potential for residual radioactivity, general supplemental information, etc. Judgment measurements are not included in the statistical evaluation of the survey unit data because they violate the assumption of randomly selected, independent measurements. Instead, judgment measurements are individually compared to the DCGLW.

karst terrain: A kind of terrain with characteristics of relief and drainage arising from a high degree of rock solubility. The majority of karst conditions occur in limestone areas, but karst may also occur in areas of dolomite, gypsum, or salt deposits. Features associated with karst terrain may include irregular topography, abrupt ridges, sink holes, caverns, abundant springs, and disappearing streams. Well developed or well integrated drainage systems of streams and tributaries are generally not present.

keV: kilo-electronvolt.

key principle: A fundamental principle that should be adhered to during land management. Through consultation, EURSSEM has developed five key principles on the protection of people and the environment, stakeholder involvement, the identification of the preferred land management option, taking immediate action and record keeping.

kg: kilogram.

klystron: An electron tube used in television, etc., for converting a stream of electrons into ultra high-frequency waves that are transmitted as a pencil-like radio beam.

^40^K: potassium-40.

LAN: Local Area Network.

LARADS: Laser-Assisted Ranging And Data System.

laser-induced fluorescence probe: A real-time technology sensor used to determine the presence of chemicals that fluoresce at standard excitation wavelengths.

LBGR: Lower Bound of the Gray Region.

LCA: Life Cycle Analysis. A systematic set of procedures for compiling and examining the inputs and outputs of materials and energy and associated environmental impacts directly attributable to the functioning of a product or service system throughout its life cycle.

LCBL: Life Cycle Baseline.

LDR: Land Disposal Restrictions.

less-than data: Measurements that are less than the minimum detectable concentration.

LET: Linear Energy Transfer.

levelling the data: The normalization of radiometric data measured under different environmental conditions, with various instruments in adjacent areas.

license: A license issued under national or international regulations.

licensee: The organisation that is the holder of the nuclear site licence on a nuclear-licensed site. The licensee is responsible for nuclear safety on the site and for discharging all the obligations and liabilities associated with the nuclear site licence.

license termination: Discontinuation of a license, the eventual conclusion to decommissioning.

LIF: Laser-Induced Fluorescence.

linear attenuation coefficient, μ (m-1): A constant describing the attenuation of a specific radiation in a particular medium – attenuation of the specified radiation per unit distance (m-1).

live time: The counting time corrected for the total dead time of the radiometric measurement.

LLC: Local Liaison Committee.

LLD: Lower Limit of Detection.

LLW: Low Level (radioactive) Waste.

LMU: Liabilities Management Unit.

LNAPL: Light Non-Aqueous Phase Liquid.

log normal distribution: is a probability distribution of a random variable whose logarithm is normally distributed.

lower bound of the gray region (LBGR): The minimum value of the gray region. The width of the gray region (DCGL-LBGR) is also referred to as the shift, Δ.

lower limit of detection (LD): The smallest amount of radiation or radioactivity that statistically yields a net result above the method background. The critical detection level, LC, is the lower bound of the 95% detection interval defined for LD and is the level at which there is a 5% chance of calling a background value “greater than background.” This value should be used when actually counting samples or making direct radiation measurements. Any response above this level should be considered as above background; i.e., a net positive result. This will ensure 95% detection capability for LD. A 95% confidence interval should be calculated for all responses greater than LC.

LQA: Land Quality Assessment.

LQS: Land Quality Statement.

LSG: Local Stakeholder Group (now called SSG: Site Stakeholder Group).

LTS: Long-Term Stewardship.

m: meter.

m: The number of measurements from the reference area used to conduct a statistical test.

m2: square meter.

made ground: Ground produced by infilling with material from outside the site or from another part of the site. Typically this could include rubble, gravel or sand or waste materials.

magnetron: A vacuum tube in which the flow of ions from the heated cathode to the anode is controlled by a magnetic field externally applied and perpendicular to the electric field by which they are propelled. Magnetrons are used to produce very short radio waves.

management of contaminated land: The taking of any actions to detect, characterise, control, monitor or remove (wholly or partially) contamination in on or under land (including groundwater) and all the processes that lead up to decisions to take such actions.

man-made radiation: Radiation from sources other than natural sources.

Marl: Friable earthy deposit consisting of clay and calcium carbonate.

MARSSIM: The Multi-Agency Radiation Survey and Site Investigation Manual is a tool developed by EPA, NRC, DOE, and DOD to determine if constituents at a radiologically contaminated site have been cleaned up to concentrations that fall below regulatory limits.

mass attenuation coefficient, μ /q (m2/kg): A constant describing the attenuation of specific radiation per unit surface density of absorbing medium. A ratio of linear attenuation coefficient μ to the density ρ of the absorbing medium.

mass number: The number of nucleons (protons and neutrons) in the nucleus of an atom.

MC: Methylene Chloride.

MCA: Multi-Channel pulse height Analyzer.

MCB: Multi-Channel Buffer.

MCL: Maximum Contaminant Level.

MDC: Minimal Detectable Concentrations.

measurement: For the purpose of EURSSEM, it is used interchangeably to mean: 1) the act of using a detector to determine the level or quantity of radioactivity on a surface or in a sample of material removed rom a media being evaluated, or 2) the quantity obtained by the act of measuring.

MeV: mega-electronvolt.

MFA: Material Flow Accounting or Analysis; a method whereby the streams of material, chemical elements, energy, etc. are assessed and possibly balanced. It is centred on the material and chemical compound, rather than on the product or service in the case of LCA. MFA covers approaches such as substance flow analysis (SFA), product flow accounts, material balancing and overall material flow accounts.

mg: milligram.

micrometeorology: The study of weather conditions in a local or very small area, such as immediately around a tree or building, that can affect meteorological conditions.
min: minute.

minimum detectable concentration (MDC): The minimum detectable concentration (MDC) is the a priori activity level that a specific instrument and technique can be expected to detect 95% of the time. When stating the detection capability of an instrument, this value should be used. The MDC is the detection limit, LD, multiplied by an appropriate conversion factor to give units of activity.

minimum detectable count rate (MDCR): The minimum detectable count rate (MDCR) is the a priori count rate that a specific instrument and technique can be expected to detect.
missing or unusable data: Data (measurements) that are mis-labelled, lost, or do not meet quality control standards. Less-than data are not considered to be missing or unusable data. See R.
mixed wastes: Radioactive waste that contains non-radioactive toxic or hazardous materials that could cause undesirable effects in the environment. Such waste has to be handled, processed and disposed of in such a manner that takes into account the chemical as well as its radioactive components.

MOX: Mixed OXide reactor fuel.

mph: miles per hour.

multi-channel amplitude analyzer: That part of a gamma ray spectrometer that sorts input pulses into channels according to the amplitude (energy) of the input pulses.

multi-channel pulse height analyzer: A device that sorts the pulses of energy leaving a scintillation detector by amplitude. The amplitude of the energy that leaves the detector is proportional to the energy that entered it, allowing investigators to determine the relative concentration and type of radionuclide present in a sample.

munitions: Military supplies, especially weapons and ammunition.

Include (from EURACHEM Guide UfS:2007) this definitions: Homogeneity, heterogeneity The degree to which a property or constituent is uniformly distributed throughout a quantity of material. Notes: 1. A material may be homogeneous with respect to one analyte or property but heterogeneous with respect to another. 2. The degree of heterogeneity (the opposite of homogeneity) is the determining factor of sampling error. IUPAC (1990) [46]; ISO 11074-2: 1.6 (1998) [45]
– by Rafael Garcia-Bermejo Fernandez about 6 years ago