QA QC FOR ENVIRONMENTAL MEASUREMENT Unit 4 Module 13

QA/QC FOR ENVIRONMENTAL MEASUREMENT Unit 4: Module 13, Lecture 1

QA/QC for environmental measurement · What is quality assurance http: /water. usgs. gov/ (QA)? · a broad plan for maintaining quality in all aspects of a program - Keith et al. (1983) · establishes the need for quality control (QC) Developed by: Zwiebel, Filbin Updated: June 14, 2005 U 5 -m 13 a-s 2

QA/QC for environmental measurement · Quality control refers to routine technical activities – the purpose of which is to control error http: //oceanexplorer. noaa. gov/explorations/02 hud son/logs/aug 29. html · QC can be considered the “HOW” of the QA process · applicable to field, lab and office procedures http: //www. jmg. gov. my/Client_s_Charter/client_s_ charter. html Developed by: Zwiebel, Filbin Updated: June 14, 2005 U 5 -m 13 a-s 3

QA for environmental measurement · Why do we need quality assurance for environmental measurement? · understand data reliability · quantify areas of analytical uncertainty · standardize measurement to allow for repeatable and comparable data across time and place QA ensures that data will meet defined standards of quality with a standard level of confidence Developed by: Zwiebel, Filbin Updated: June 14, 2005 U 5 -m 13 a-s 4

QA for environmental assessment · Need for consistency - monitoring a copper impacted stream · Is this problem getting worse or is being mitigated? · How can you tell? · Why is standardized measurement so important? http: //www. darcnw. noaa. gov/bbpix. htm Developed by: Zwiebel, Filbin Updated: June 14, 2005 U 5 -m 13 a-s 5

Where is QA applicable? · Who in the environmental arena uses quality assurance measures and when is it necessary? · nearly all REGULATORY decisions about: issuing permits, monitoring human health and environmental quality, pollution investigations and the progress of site remediation are based on one thing -- the data gathered from the site. Developed by: Zwiebel, Filbin Updated: June 14, 2005 U 5 -m 13 a-s 6

Where is QA applicable? · What other environmental arenas utilize quality assurance measures? · laboratories · universities and research organization Developed by: Zwiebel, Filbin Updated: June 14, 2005 U 5 -m 13 a-s 7

Where is QA applicable? · Non-research areas utilize environmental QA measures also · business and industry · lobbying groups and special interests · legislators · lawyers · others http: //www. lanl. gov/orgs/pa/News/060297. html http: //gov. state. nv. us/S pecial. Sessio n 072902. asp Developed by: Zwiebel, Filbin Updated: June 14, 2005 U 5 -m 13 a-s 8

Quality assurance vs. quality control · Quality Assurance (QA) · broad program plan · establishes the need for QC Developed by: Zwiebel, Filbin · Quality Controls (QC) · individual checks and balances · the “HOW” of QA Updated: June 14, 2005 U 5 -m 13 a-s 9

Where is QC applicable? · Quality control is applicable in all aspects of a project including: · Field data collection and sampling · Laboratory analysis and processing · Data evaluation and assessment · Reporting and project documentation QC provides steps that ensure data will meet defined standards of quality with a standard level of confidence Developed by: Zwiebel, Filbin Updated: June 14, 2005 U 5 -m 13 a-s 10

QC in the field · QC is particularly critical in filed data collection · often the most costly aspect of a project · data is never reproducible under the exact same condition or setting http: //climchange. cr. usgs. gov/info/lacs/wate rsampling. htm sechi readings Developed by: Zwiebel, Filbin field filtration Updated: June 14, 2005 http: //www. fe. doe. gov/techline/tl_h ydrates_oregon. shtml logging sea cores U 5 -m 13 a-s 11

QC in the field · Standardized field method programs · US Army Corps of Engineers · ASTM methods · USGS classification · APHA · AIHA · NIST Developed by: Zwiebel, Filbin Updated: June 14, 2005 U 5 -m 13 a-s 12

QC in the laboratory · Laboratory data analysis, measurement and acquisition: · Chain of custody forms · Equipment calibration · Storage practices · Analytical methods · Holding times · MDLs www. odc. gov/noeh/dls Developed by: Zwiebel, Filbin Updated: June 14, 2005 U 5 -m 13 a-s 13

QC in the laboratory · Standardized laboratory method programs · EPA Methods · State Modified Methods · APHA Methods · ASTM · AIHA Developed by: Zwiebel, Filbin Updated: June 14, 2005 U 5 -m 13 a-s 14

QC in the office · In office planning, data evaluation and summation of results: · QAPP – quality assurance project plan outlines all · project management · assessment and oversight · data validation http: //www. va. gov/optometry/page. cfm? pg=4 Developed by: Zwiebel, Filbin Updated: June 14, 2005 www. cr. nps. gov/aad/collections/ mgt_pr. htm Photo from MN DNR U 5 -m 13 a-s 15

QC for environmental measurement · Why do we need quality control? · To prevent errors from happening · To identify and correct errors that have taken place QC is used to PREVENT and CORRECT ERRORS Developed by: Zwiebel, Filbin Updated: June 14, 2005 U 5 -m 13 a-s 16

QC: Internal vs. external measures · Internal quality control · “controllable” by those responsible for undertaking the project or directly “involved in the program” · External quality control · a “set of measures” established for and conducted by those people and organizations “outside of the program” Developed by: Zwiebel, Filbin Updated: June 14, 2005 U 5 -m 13 a-s 17

Quality control (QC): Internal · Internal Quality Control: · Equipment calibration · Proper training and http: //www. ars. usda. gov/is/np/fnrb 1001. htm certification of participants · Proper sampling and containment techniques · Proper data documentation http: //il. water. usgs. gov/adcp/photos/class_apr 99. html Developed by: Zwiebel, Filbin Updated: June 14, 2005 U 5 -m 13 a-s 18

Quality control (QC): External · External quality control: · Performance audits · Split sample analysis · Replicate (duplicate) http: //www. ars. usda. gov/is/np/fnrb 1001. htm sample analysis http: //www. tfhrc. gov/pubrds/novdec 98/seven. htm Developed by: Zwiebel, Filbin Updated: June 14, 2005 U 5 -m 13 a-s 19

Quality Assurance Project Plans (QAPP) · A quality assurance project plan (QAPP) is a project-specific QA document. · The QAPP outlines the QC measures used in implementing the project. Developed by: Zwiebel, Filbin Updated: June 14, 2005 U 5 -m 13 a-s 20

Quality Assurance Project Plans (QAPP) · The QAPP governs work conducted in the field, laboratory, and the office. · The QAPP: · guides the selection of project parameters and procedures · guides data management and analysis · provides steps to determine the validity of specific sampling or analysis procedures · designates both internal and external QC measures Developed by: Zwiebel, Filbin Updated: June 14, 2005 U 5 -m 13 a-s 21

QA/QC: Data objective and key concepts · Successful data collection and analysis is dependant upon “The PARCC Parameters”: · Precision · Accuracy · Representativeness · Completeness · Comparability The key concepts of QA/QC are the “PARCC” Parameters – the WHY of the QAPP Developed by: Zwiebel, Filbin Updated: June 14, 2005 U 5 -m 13 a-s 22

Key concepts of QA/QC: · Precision · degree of agreement there is between repeated measurements of the same characteristic · can be biased – meaning there is a consistent error in the results · Accuracy · measures how close data results are to a true or expected value – does not allow for bias http: //www. d. umn. edu/faculty/ UMD med school Developed by: Zwiebel, Filbin Updated: June 14, 2005 U 5 -m 13 a-s 23

Key concepts of QA/QC: Accuracy · accuracy = (average value) – (true value) · precision represents repeatability · bias represents amount of error · low bias and high precision = statistical accuracy http: //www. epa. gov/owow/monitoring/volunteer/qappexec. html Developed by: Zwiebel, Filbin Updated: June 14, 2005 U 5 -m 13 a-s 24

Key concept QA/QC: Representativeness · extent to which measurements actually represent the true environmental condition or population at the time a sample was collected. · Representative data should result in repeatable data Does this represent this? ? http: //pubs. usgs. gov/fs/fs-0058 -99 Developed by: Zwiebel, Filbin Updated: June 14, 2005 U 5 -m 13 a-s 25

Key concepts of QA/QC: Completeness · comparison between the amount of data intended to be collected vs. actual amount of valid (usable) data collected. · In the design of the QAPP – will the goals of the plan meet assessment needs? · Will sufficient data be collected? Would this give usable data ? ? Developed by: Zwiebel, Filbin Updated: June 14, 2005 U 5 -m 13 a-s 26

Key concepts of QA/QC: Comparability · the extent to which data can be compared between sample locations or periods of time within a project, or between projects Will similar data from these sites be Comparable ? ? http: //www. nssl. noaa. gov/publicaffairs/bac kgrounders/backgrounder_ww. html http: //www. nrcs. usda. gov/programs/ctasummary. html Developed by: Zwiebel, Filbin Updated: June 14, 2005 U 5 -m 13 a-s 27

Review: QA vs. QC · Quality Assurance (QA) · broad program plan · establishes the need for QC Developed by: Zwiebel, Filbin · Quality Controls (QC) · standardized tests and methods · the “HOW” of QA Updated: June 14, 2005 U 5 -m 13 a-s 28

Review: Quality Assurance Project Plans · The QAPP is a project-specific QA document. · The QAPP outlines the QC measures to be taken for the project. Developed by: Zwiebel, Filbin · QAPP guides: · the selection of parameters and procedures · data management and analysis · steps taken to determine the validity of specific sampling or analysis procedures Updated: June 14, 2005 U 5 -m 13 a-s 29

Elements of a QAPP · The QAPP governs work conducted in the field, laboratory, and the office. · QAPP can be broken out into four areas of the project · Project management (office) · Measurement and data acquisition (field and lab) · Assessment and oversight (field, lab, and office) · Data validation and usability (field, lab, and office) Developed by: Zwiebel, Filbin Updated: June 14, 2005 U 5 -m 13 a-s 30

Review: QA/QC key concepts · “The PARCC Parameters” are the WHY of QA/QC and assure successful data analysis: · Precision · Accuracy · Representativeness · Completeness · Comparability The key concepts and WHY of QA/QC are the “PARCC” Parameters Developed by: Zwiebel, Filbin Updated: June 14, 2005 U 5 -m 13 a-s 31

References · EPA 1996, Environmental Protection Agency Volunteer Monitor’s Guide to: Quality Assurance Project Plans. 1996. EPA 841 -B-96 -003, Sep 1996, U. S. EPA, Office of Wetlands, Washington, D. C. 20460, USA http: //www. epa. gov/owowwtr 1/monitoring/volunteer/qappexe c. htm Developed by: Zwiebel, Filbin Updated: June 14, 2005 U 5 -m 13 a-s 32

• http: //waterontheweb. org/index. html Developed by: Zwiebel, Filbin Updated: June 14, 2005 U 5 -m 13 a-s 33