1、Designation: D7352 18Standard Practice forVolatile Contaminant Logging Using a Membrane InterfaceProbe (MIP) in Unconsolidated Formations with Direct PushMethods1This standard is issued under the fixed designation D7352; the number immediately following the designation indicates the year oforiginal
2、adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope*1.1 This standard practice describes a field procedure for therapid del
3、ineation of volatile organic compounds (VOC) in thesubsurface using a membrane interface probe. Logging withthe membrane interface probe is usually performed with directpush (DP) equipment. DP methods are typically used in soilsand unconsolidated formations, not competent rock.1.2 This standard prac
4、tice describes how to obtain a realtime vertical log of VOCs with depth. The data obtained isindicative of the total VOC level in the subsurface at depth.The MIP detector responses provide insight into the relativecontaminant concentration based upon the magnitude of detec-tor responses and a determ
5、ination of compound class basedupon which detectors of the series respond.1.3 The use of a lithologic logging tool is highly recom-mended to define hydrostratigraphic conditions, such as migra-tion pathways, and to guide confirmation sampling and reme-diation efforts. Other sensors, such as electric
6、al conductivity,hydraulic profiling tool, fluorescence detectors, and conepenetration tools may be included to provide additional infor-mation.1.4 Since MIP results are not quantitative, soil and watersampling (Guides D6001, D6282, D6724, and Practice D6725)methods are needed to identify specific an
7、alytes and exactconcentrations. MIP detection limits are subject to the selec-tivity of the gas phase detector applied and characteristics ofthe formation being penetrated (for example: permeability,saturation, clay and organic carbon content).1.5 The values stated in either SI units or inch-pound u
8、nitsgiven in brackets are to be regarded separately as standard.The values stated in each system may not be exact equivalents;therefore, each system shall be used independently of the other.Combining values from the two systems may result in non-conformance with the standard. Reporting of test resul
9、ts inunits other than SI shall not be regarded as nonconformancewith this standard.1.6 All observed and calculated values shall conform to theguidelines for significant digits and rounding established inPractice D6026, unless superseded by this standard.1.6.1 The procedures used to specify how data
10、is collected/recorded and calculated in the standard are regarded as theindustry standard. In addition, they are representative of thesignificant digits that generally should be retained. The proce-dures used do not consider material variation, purpose forobtaining the data, special purpose studies,
11、 or any consider-ations for the users objectives; and it is common practice toincrease or reduce significant digits of reported data to becommensurate with these considerations. It is beyond the scopeof these test methods to consider significant digits used inanalytical methods for engineering data.
12、1.7 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 applicable in all circumstances. This ASTM standard is
13、 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 means that the document has been approved thro
14、ugh theASTM consensus process.1.8 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, health, and environmental practices and deter-mine the applicability of regul
15、atory limitations prior to use.1.9 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decision on Principles for theDevelopment of International Standards, Guides and Recom-mendations issued by the World Trade Or
16、ganization TechnicalBarriers to Trade (TBT) Committee.1This practice is under the jurisdiction of ASTM Committee D18 on Soil andRock and is the direct responsibility of Subcommittee D18.21 on Groundwater andVadose Zone Investigations.Current edition approved July 15, 2018. Published August 2018. Ori
17、ginallyapproved in 2007. Last previous edition approved in 2012 as D735207(2012).DOI: 10.1520/D7352-18.*A Summary of Changes section appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United StatesThis international
18、standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.12
19、. Referenced Documents2.1 ASTM Standards:2D653 Terminology Relating to Soil, Rock, and ContainedFluidsD3740 Practice for Minimum Requirements for AgenciesEngaged in Testing and/or Inspection of Soil and Rock asUsed in Engineering Design and ConstructionD5092 Practice for Design and Installation of G
20、roundwaterMonitoring WellsD5299 Guide for Decommissioning of Groundwater Wells,Vadose Zone Monitoring Devices, Boreholes, and OtherDevices for Environmental ActivitiesD5730 Guide for Site Characterization for EnvironmentalPurposes With Emphasis on Soil, Rock, the Vadose Zoneand Groundwater (Withdraw
21、n 2013)3D5792 Practice for Generation of Environmental Data Re-lated to Waste Management Activities: Development ofData Quality ObjectivesD6001 Guide for Direct-Push Groundwater Sampling forEnvironmental Site CharacterizationD6026 Practice for Using Significant Digits in GeotechnicalDataD6067 Practi
22、ce for Using the Electronic Piezocone Pen-etrometer Tests for Environmental Site Characterizationand Estimation of Hydraulic ConductivityD6282 Guide for Direct Push Soil Sampling for Environ-mental Site CharacterizationsD6724 Guide for Installation of Direct Push GroundwaterMonitoring WellsD6725 Pra
23、ctice for Direct Push Installation of PrepackedScreen Monitoring Wells in Unconsolidated AquifersD8037 Practice for Direct Push Hydraulic Logging forProfiling Variations of Permeability in SoilsE355 Practice for Gas Chromatography Terms and Relation-shipsE1689 Guide for Developing Conceptual Site Mo
24、dels forContaminated Sites3. Terminology3.1 For definitions of common technical terms used in thisstandard, refer to Terminology D653.3.2 Definitions of Terms Specific to This Standard:3.2.1 carry overretention of contaminant in the membraneand trunkline which may result in false positive results or
25、 anincreased detector baseline at subsequent depth intervals.3.2.2 chemical response testa test of the working MIPsystem performed by exposing the MIP membrane to anaqueous phase solution with a known contaminant of knownconcentration.3.2.2.1 DiscussionPerformed before and after each MIPlog to valid
26、ate the MIP system performance. Also used so thatlog data from different locations across a site may be com-pared.3.2.3 closed couple flowthe trunkline carrier gas returnflow with the trunkline gas lines connected together when theMIP probe is bypassed.3.2.3.1 DiscussionUsed during troubleshooting t
27、o deter-mine the source of a gas leak in the MIP system.3.2.4 gas dryera selectively permeable membrane tubingis used to continuously dry the MIP carrier gas stream beforeit enters the detectors by removing only water vapor.3.2.4.1 DiscussionThe gas dryer may need to be removedto improve detection o
28、f some analytes with high watersolubility, such as MTBE, acetone, dioxane or ethanol.3.2.5 gas phase detectorsheated laboratory grade detec-tors used for gas chromatography (Practice E355).3.2.5.1 DiscussionCarrier gas effluent from the MIPprobeflows through these detectors at the surface for the an
29、alysis ofVOCs. Detectors most often used with the MIP includephotoionization detector (PID), flame ionization detector(FID), and a halogen specific detector (XSD) (Fig. A2.2).Other, appropriate gas phase detectors may be used.3.2.6 membrane interface probe (MIP)a subsurface log-ging tool for detecti
30、on of VOCs.3.2.7 parts per billion (ppb)the number of units of acontaminant per 1 billion units of total mass, typically mea-sured as either g/Kg or g/L depending if a solid or liquid isbeing measured.3.2.8 parts per million (ppm)the number of units of acontaminant per 1 million units of total mass,
31、 typicallymeasured as either mg/Kg or mg/L depending if a solid orliquid is being measured.3.2.9 triggersoftware icon interface between the operatorand the acquisition software to initiate or terminate datacollection.3.2.10 trip timethe time required for an analyte to diffuseacross the semipermeable
32、 membrane and travel to the gasphase detectors at the surface through a fixed length of tubing.3.2.11 trunklinea durable, protective jacketed cord con-taining electrical wires for the heaters in the probe block,electrical wires for other sensors, and tubing for the transportof carrier gas and the an
33、alytes to the surface detectors which ispre-strung through steel drive rods prior to logging.3.2.11.1 DiscussionThe trunkline connects the MIP probecontaining the onboard sensors with the surface instrumenta-tion.3.2.12 working standardan aqueous chemical standardused in response testing the MIP sys
34、tem.4. Summary of Practice4.1 This practice describes the field method for delineationof VOCs with depth via the MIP (1-4).4The MIP is advancedthrough the soil or unconsolidated formations using a direct2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Ser
35、vice at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3The last approved version of this historical standard is referenced onwww.astm.org.4The boldface numbers in parentheses refer to the list of references at th
36、e end ofthis standard.D7352 182push machine for high resolution logging of volatile analytes inreal time. Other sensors may be run in tandem with the MIP(e.g. electrical conductivity (EC), hydraulic profiling tool(HPT), cone penetration testing (CPT) to provide lithologicdata simultaneously (5-7, D6
37、067, D8037).4.2 A semipermeable membrane on the probe is heated to atemperature of 100 to 120C 212 to 250F. Clean carrier gasis circulated across the internal surface of the membrane.VOCs diffuse across the membrane under a concentrationgradient into the carrier gas. The VOCs are transported in thec
38、arrier gas by the return gas line to the surface for analysis bygas phase detectors (Fig. 1).4.3 After pre-log quality assurance tests the MIP probe isadvance into the subsurface. Probe advancement is halted atpredefined depth increments (for example, every 30 cm 1 ft.)depending on the level of vert
39、ical detail required. Probeadvancement is stopped for about 45 seconds at each depth.This allows time for the heater to warm the probe/formation,for VOCs to cross the membrane into the carrier gas line andtravel to the up-hole detector system, and for desorption ofcontaminants off the membrane after
40、 passing through contami-nated zones.4.4 Detector responses and data from other sensors areobserved onscreen as the log is obtained.4.5 Detector responses and data from other sensors (such asEC, HPT, CPT) are saved in the digital logfile. The logfiles canbe retrieved, after log completion, in a view
41、ing softwarepackage. Logs may be printed for reports or viewed onscreen.4.6 After reaching the end of the log the probe is retractedusing the DP machine.4.7 MIP bore holes must be properly sealed to meet localregulatory code.5. Significance and Use5.1 The MIP system provides a timely and cost effect
42、iveway for delineation of many VOC plumes (for example,gasoline, benzene, toluene, solvents, trichloroethylene, tetra-chloroethylene) with depth (1, 2, 4, 8, 9). MIP detector logsprovide insight into the relative contaminant concentrationbased upon the response magnitude of detector and a determi-na
43、tion of compound class based upon which detectors of theseries respond of the bulk VOC distribution in the subsurfacebut do not provide analyte specificity (1, 2, 7). DPlogging toolssuch as the MIP are often used to perform expedited sitecharacterizations (10, 11, D5730) and develop detailed concep-
44、tual site models (E1689). The project manager should deter-mine if the required data quality objectives (D5792) can beachieved with a MIP investigation. MIP logging is typicallyone part of an overall investigation program.5.2 MIP logs provide a detailed record of VOC distributionin the saturated and
45、 unsaturated formations and assist inevaluating the approximate limits of potential contaminants. Aproportion of the halogenated and non-halogenated VOCs inthe sorbed, aqueous, or gaseous phases partition through themembrane for detection up hole (1).5.3 Many factors influence the movement of volati
46、le com-pounds from the formation across the membrane and into thecarrier gas stream. One study has evaluated the effects oftemperature and pressure at the face of the membrane onanalyte permeability (12). Formation factors such as degree ofsaturation, clay content, proportion of organic carbon, poro
47、sityand permeability will also influence the efficiency of analytemovement from the formation across the membrane. Of course,the volatility, concentration, molecular size and mass, andwater solubility of each specific VOC will influence movementacross the membrane and rate of transport through the c
48、arriergas line to the detectors.5.4 High analyte concentrations or the presence of Non-Aqueous Phase Liquid (NAPL) in the formation can result inanalyte carry over in the MIPlog (8, 13).This is a result of highanalyte concentrations within the membrane matrix requiringtime to diffuse out of the memb
49、rane into the carrier gas stream.This effect can lead to tailing of detector peaks on the MIP logto deeper intervals. Use of appropriate detectors and detectorsensitivity settings can reduce this effect (14). Experience withlog interpretation also helps to identify analyte carryover. Ofcourse, targeted soil or groundwater sampling (D6001, D6282)FIG. 1 The Primary Components of a Typical MIP SystemD7352 183should be performed routinely to verify log results and assistwith log interpretation and site characterization (subsection1.4).5.5 Some volatile cont
copyright@ 2008-2019 麦多课文库(www.mydoc123.com)网站版权所有
备案/许可证编号:苏ICP备17064731号-1