ASTM_D_5717_-_95e1.pdf

Designation:D 5717 95e1Standard Guide forDesign of Ground-Water Monitoring Systems in Karst andFractured-Rock Aquifers1This standard is issued under the fixed designation D 5717;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon(e)indicates an editorial change since the last revision or reapproval.e1NOTEParagraph 1.5 was added editorially October 1998.INTRODUCTIONThis guide for the design of ground-water monitoring systems in karst and fractured-rock aquiferspromotes the design and implementation of accurate and reliable monitoring systems in those settingswhere the hydrogeologic characteristics depart significantly from the characteristics of porous media.Variances from government regulations that require on-site monitoring wells may often be necessaryin karst or fractured-rock terranes(see 7.3)because such settings have hydrogeologic features thatcannot be characterized by the porous-media approximation.This guide will promote the developmentof a conceptual hydrogeologic model that supports the need for the variances and aids the designer orgovernmental reviewer in establishing the most reliable and efficient monitoring system for suchaquifers.Many of the approaches contained in this guide may also have value in designing ground-watermonitoring systems in heterogeneous and anisotropic unconsolidated and consolidated granularaquifers.The focus of this guide,however,is on unconfined karst systems where dissolution hasincreased secondary porosity and on other geologic settings where unconfined ground-water flow infractures is a significant component of total ground-water flow.1.Scope1.1 JustificationThis guide considers the characterizationof karst and fractured-rock aquifers as an integral componentof monitoring-system design.Hence,the development of aconceptual hydrogeologic model that identifies and defines thevarious components of the flow system is recommended priorto the design and implementation of a monitoring system.1.2 Methodology and ApplicabilityThis guide is based onrecognized methods of monitoring-system design and imple-mentation for the purpose of collecting representative ground-water data.The design guidelines are applicable to the deter-mination of ground-water flow and contaminant transport fromexisting sites,assessment of proposed sites,and determinationof wellhead or springhead protection areas.1.3 ObjectivesThe objectives of this guide are to outlineprocedures for obtaining information on hydrogeologic char-acteristics and water-quality data representative of karst andfractured-rock aquifers.1.4 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.1.5 This guide offers an organized collection of informationor a series of options and does not recommend a specificcourse of action.This document cannot replace education orexperience and should be used in conjunction with professionaljudgment.Not all aspects of this guide may be applicable in allcircumstances.This ASTM standard is not intended to repre-sent or replace the standard of care by which the adequacy ofa given professional service must be judged,nor should thisdocument be applied without consideration of a projects manyunique aspects.The word“Standard”in the title of thisdocument means only that the document has been approvedthrough the ASTM consensus process.2.Referenced Documents2.1 ASTM Standards:D 653 Terminology Relating to Soil,Rock,and ContainedFluids2D 5092 Practice for Design and Installation of GroundWater Monitoring Wells in Aquifers3D 5254 Practice for Minimum Set of Data Elements toIdentify a Ground-Water Site31This guide is under the jurisdiction of ASTM Committee D-18 on Soil andRock and is the direct responsibility of Subcommittee D18.21 on Ground Water andVadose Zone Investigations.Current edition approved April 15,1995.Published June 1995.2Annual Book of ASTM Standards,Vol 04.08.3Annual Book of ASTM Standards,Vol 04.09.1Copyright ASTM,100 Barr Harbor Drive,West Conshohocken,PA 19428-2959,United States.3.Terminology3.1 Definitions:3.1.1 For terms not defined below,see Terminology D 653.3.2 Definitions of Terms Specific to This Standard:3.2.1 aliasingthe phenomenon in which a high-frequencysignal can be interpreted as a low-frequency signal or trendbecause the sampling was too infrequent to characterize thesignal.3.2.2 conduitpipe-like opening formed and enlarged bydissolution of bedrock and that has dimensions sufficient tosustain turbulent flow under ordinary hydraulic gradients.3.2.3 dissolution zonea zone where extensive dissolutionof bedrock has occurred;void size may range over severalorders of magnitude.3.2.4 epikarst