1、Designation: D 7352 07Standard Practice forDirect Push Technology for Volatile Contaminant Loggingwith the Membrane Interface Probe (MIP)1, 2This standard is issued under the fixed designation D 7352; the number immediately following the designation indicates the year oforiginal adoption or, in the
2、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.1. Scope1.1 This standard practice describes a method for rapiddelineation of volatile organic cont
3、aminants (VOC) in thesubsurface using a membrane interface probe. Logging withthe membrane interface probe is usually performed with directpush equipment.1.2 This standard practice describes how to obtain a realtime vertical log of volatile organic contaminants with depth.The data obtained is indica
4、tive of the total volatile organiccontaminant concentration in the subsurface at depth.1.3 Other sensors, such as electrical conductivity, fluores-cence detectors, and cone penetration tools may be included toprovide additional information. The use of a lithologic loggingtool is highly recommended t
5、o define hydrostratigraphic con-ditions, such as migration pathways, and to guide confirmationsampling.1.4 LimitationsThe MIP system does not provide speci-ficity of analytes. This tool is to be used as a total volatileorganic contaminant-screening tool. Soil and/or water sam-pling (Guides D 6001, D
6、 6282, D 6724, and Practice D 6725)must be performed to identify specific analytes and exactconcentrations. Only VOCs are detected by the MIP system inthe subsurface. Detection limits are subject to the selectivity ofthe gas phase detector applied and characteristics of theformation being penetrated
7、 (for example, clay and organiccarbon content).1.5 This practice offers a set of instructions for performingone or more specific operations. This document cannot replaceeducation or experience and should be used in conjunctionwith professional judgment. Not all aspects of this practice maybe applica
8、ble in all circumstances. This ASTM standard is notintended to represent or replace the standard of care by whichthe adequacy of a given professional service must be judged,nor should this document be applied without the considerationof a projects many unique aspects. The word “standard” in thetitle
9、 means that the document has been approved through theASTM consensus process.1.6 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 determ
10、ine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:3D 653 Terminology Relating to Soil, Rock, and ContainedFluidsD 5299 Guide for Decommissioning of Ground WaterWells, Vadose Zone Monitoring Devices, Boreholes, andOther Devices for Environmental A
11、ctivitiesD 6001 Guide for Direct-Push Ground Water Sampling forEnvironmental Site CharacterizationD 6282 Guide for Direct Push Soil Sampling for Environ-mental Site CharacterizationsD 6724 Guide for Installation of Direct Push Ground WaterMonitoring WellsD 6725 Practice for Direct Push Installation
12、of PrepackedScreen Monitoring Wells in Unconsolidated AquifersE 355 Practice for Gas Chromatography Terms and Rela-tionships3. Terminology3.1 Terminology used within this practice is in accordancewith Terminology D 653 with the addition of the following:3.2 Definitions:3.2.1 carry overretention of c
13、ontaminant in the mem-brane and trunkline which may result in false positive results oran increased detector baseline at subsequent depth intervals.3.2.2 closed couple flowgas flow in the MIP system whena probe is detached and the gas lines are coupled together. Theflow is then measured with a gas f
14、low meter on the returntubing before entering the gas phase detectors. Used to verifycontinuity of gas flow in the MIP system.1This practice is under the jurisdiction of ASTM Committee D18 on Soil andRock and is the direct responsibility of Subcommittee D18.21 on Ground Water andVadose Zone Investig
15、ations.Current edition approved May 15, 2007. Published July 2007.2The Membrane Interface Probe is covered by a patent. Interested parties areinvited to submit information regarding the identification of an alternative(s) to thispatented item to the ASTM Headquarters. Your comments will receive care
16、fulconsideration at a meeting of the responsible technical committee, which you mayattend.3For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Sum
17、mary page onthe ASTM website.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.3.2.3 gas dryera selectively permeable membrane tubing(Nafiont) is used to continuously dry the MIP carrier gasstream by removing only water vapor.3.2.4 gas
18、 phase detectorsheated laboratory grade detec-tors used for gas chromatography (Practice E 355). Gas effluentfrom the MIP flows through these detectors for the analysis ofVOC compounds. Detectors most often used with the MIPinclude photoionization detector (PID), flameionization detec-tor (FID), and
19、 an electron capture detector (ECD).3.2.5 membrane interface probe (MIP)a subsurface log-ging tool for detection of volatile organic compounds (VOCs).3.2.6 response testa test of the working MIP systemperformed by placing the MIP probe in an aqueous phasesolution with a known contaminant of known co
20、ncentration.Performed before each MIPlog is conducted and one at the endof the working day to validate the MIP system performance.Also used to compare data from individual locations.3.2.7 triggermechanical interface between the operatorand instrumentation to initiate or terminate data collection.3.2
21、.8 trip timethe time required for a contaminant topenetrate the semi-permeable membrane and travel to the gasphase detectors at the surface through a fixed length of tubing.3.2.9 trunklineplastic or metal jacketed cord containingelectrical wires for the heaters in the probe block, electricalwires fo
22、r other sensors, and tubing for the transport of carriergas and the contaminant to the surface and detectors.3.2.10 working standarda chemical standard used in re-sponse testing the MIP system. This standard is a dilutedconcentration of an analyte stock standard, used for oneapplication and then pro
23、perly disposed.4. Summary of Practice4.1 This practice describes the field method for delineationof volatile organic contaminants with depth via the MembraneInterface Probe (MIP). The MIP is a continuously samplingtool advanced through the soil using a direct push machine forthe purpose of logging c
24、ontaminant and lithologic data in realtime (1, 2).44.2 A semipermeable membrane on the probe is heated to atemperature of 100 to 120C. Clean carrier gas is circulatedacross the internal surface of the membrane carrying volatileorganic contaminants, which have diffused (3) through themembrane, to the
25、 surface for analysis by gas phase detectors.5. Significance and Use5.1 The MIP system provides a timely and cost effectiveway (4) for delineation of volatile organic contaminants (forexample, benzene, toluene, solvents, trichloroethylene, tetra-chloroethylene) with depth (5, 6). Recent investigatio
26、n (2) hasfound the MIP can be effective in locating zones where densenonaqueous phase liquids (DNAPL) may be present. MIPprovides real-time measurement for optimizing selection ofsample locations when using a dynamic work plan. By identi-fying the depth at which a contaminant is located, a morerepre
27、sentative sample of soil or water can be collected.5.2 Correlation of a series of MIP logs across a site canprovide 2-D and 3-D definition of the contaminant plume.When lithologic logs are obtained (EC, CPT, etc.) with the MIPdata, contaminant migration pathways may be defined.5.3 The MIP logs provi
28、de a detailed record of contaminantdistribution in the saturated and unsaturated formations. Aproportion of the chlorinated and non-chlorinated volatileorganic contaminants in the sorbed, aqueous, or gaseous phasespartition through the membrane for detection up hole.5.4 The data obtained from applic
29、ation of this practice maybe used to guide soil (Guide D 6282) and groundwater sam-pling (Guide D 6001) or placement of long-term monitoringwells (Guide D 6724).5.5 MIP data can be used to optimize site remediation byknowing the depth distribution of volatile organic contami-nants. For example, mate
30、rials injected for remediation areplaced at correct depths in the formation.5.6 This practice also may be used as a means of evaluatingremediation performance. MIP can provide a cost-effectiveway to monitor the progress of remediation. When properlyperformed at suitable sites, logging locations can
31、be comparedfrom the initial investigation to the monitoring of the contami-nant under remediation conditions.NOTE 1The quality of the result produced by this standard isdependent on the competence of the personnel performing it, and thesuitability of the equipment and facilities used. Practitioners
32、that meet thecriteria of Practice D 3740 are generally considered capable of competentand objective testing/sampling/inspection/etc. Users of this standard arecautioned that compliance with Practice D 3740 does not in itself assurereliable results. Reliable results depend on many factors; Practice D
33、 3740provides a means of evaluating some of those factors. Practice D 3740 wasdeveloped for agencies engaged in the testing and/or inspection of soilsand rock. As such, it is not totally applicable to agencies performing thispractice. However, users of this practice should recognize that theframewor
34、k of Practice D 3740 is appropriate for evaluating the quality ofan agency performing this practice. Currently there is no known qualify-ing national authority that inspects agencies that perform this practice.6. Apparatus6.1 GeneralThe following discussion provides descrip-tions and details for the
35、 Membrane Interface Probe and systemcomponents (Fig. 1). Additional details on the MIP system areavailable in the Geoprobe MIP SOP (1).6.1.1 The American Society for Testing and Materials takesno position respecting the validity of any patent rights assertedin connection with any item mentioned in t
36、his standard. Usersof this standard are expressly advised that determination of thevalidity of any such patent rights, and the risk of infringementof such rights, are entirely their own responsibility.6.2 Membrane Interface ProbeThe MIP is the interfacebetween the bulk formation and the gas phase de
37、tectors uphole. Volatile compounds outside the probe diffuse across themembrane and are swept up hole via an inert carrier gas (Fig.2).6.2.1 The membrane is set in a removable insert. It isconstructed of a polymer coating impregnated into stainlesssteel wire mesh.6.2.2 The membrane is inserted into
38、a heater block. Theelevated temperature of the heater block is used to speed thediffusion of contaminants out of the bulk formation and4The boldface numbers in parentheses refer to the list of references at the end ofthis standard.D7352072through the membrane. This heater block has a regulatedtemper
39、ature typically set at 100 to 120C.6.2.3 Tubing is used to supply carrier gas to the membrane.Two tubes are used: a supply tube running from the carrier gassource to the membrane and a return tube running from themembrane to the gas phase detectors at ground surface.6.2.4 The MIP system may be confi
40、gured with a soilelectrical conductivity dipole for simultaneous collection ofgeneral lithologic data.6.2.5 The MIP probe may be coupled to a CPT probe at itslower end for simultaneous collection of CPT data (Fig. 3).6.3 MIP TrunklineThis cable consists of electrical wiresfor heating the MIP heater
41、block and supplying voltage toadditional sensors. The trunkline also contains gas lines for thetransport of VOCs from the probe to detectors up-hole. Thistrunkline is packaged in a durable, protective jacketing to beprestrung through steel drive rods prior to logging (Fig. 2).6.4 MIP ControllerThe M
42、IP controller is used to controlthe flow delivered to the membrane and the voltage deliveredto the heater block and electrical conductivity dipole electrode.The primary features of the MIP controller include:6.4.1 Primary pressure regulator to control the pressure ofcarrier gas to the flow regulatio
43、n circuit of the MIP controller.6.4.2 A mass flow controller is used to regulate the flow ofcarrier gas through the MIP system. Typical flow rates of 20 to60 mL/min are used in the operation of the membrane interfaceprobe.6.4.3 Temperature controller regulates the voltage suppliedto the heater block
44、 to maintain an elevated temperature in thesubsurface. The temperature controller has two outputs on anLCD. The top output is the temperature of the membrane in theheater block. The bottom output is the set temperature of thecontroller; the manufacturer sets this temperature at 121C.6.4.4 Analog sig
45、nal input from the detector system. Theanalog outputs from the gas phase detectors are connected tothe controller to be transferred to the data acquisition system.6.5 Data Acquisition SystemThe primary purpose of thissystem is to save and graph data collected from the MIP probeand detector system in
46、 real time. The data saved by theacquisition system are: depth; soil electrical conductivity; rateof probe penetration into the subsurface; temperature of theprobe; pressure of the carrier gas supply at the flow controller;and four possible gas phase detector inputs. The primarycomponents of the dat
47、a acquisition system include:6.5.1 Alpha/numeric keypad for entry of site location infor-mation,6.5.2 Internal and/or external data storage device for trans-fer of data from acquisition system to desktop or laptopcomputers, and6.5.3 Global positioning system connections for acquiringlatitude and lon
48、gitude locations of logging location and storageof this data directly to the log file.6.6 Detector SystemLaboratory grade, gas phase detec-tors are needed for the detection of volatile organic contami-nants in the carrier gas stream. Detectors may be in a gaschromatograph or in a stand-alone chassis
49、. Different detectorsare used for identification of species groups of volatile com-pounds, not individual volatile compounds. Certain detectorsmay be operated in series for the detection of differentcontaminant types. A brief discussion of commonly useddetectors with the MIP system is provided.6.6.1 Photoionization Detector (PID)The PID uses anintense beam of ultraviolet radiation to ionize molecules in theeffluent of the MIPcarrier gas stream for analyte detection. ThePID is a non-destructive detector and can therefore be used inseries with other detector types.
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