SRITN12 - page 321

INJECTORS
Purge & Trap
Sample Preparation
Method 5035
Method5035stylepurgeand trap isfor theanalysisofVOCs thatarepurgeablefromsoilat40oC. This
methoddoes not allow theVOC’s to escape theVOAvial until it is puncturedby the5035purgehead
needles. Approximately5gofsoil,weighed in thefieldat the timeofcollection, issealed inapre-weighed,
septum-sealed,screw-topVOAvialcontainingapreservativesolution. There isnoneed to insertamagnetic
stirringbarsince theSRIpurgeand trapmechanicallyagitates theVOAvialduring theanalysis. Organic-free
reagentwater,surrogates,andinternalstandards(ifapplicable)areaddedthroughthesyringeportimmediately
beforebeginningtheanalysis.
1. Insert theVOAvialcontaining5gofsoiland5mLofreagentwater into theMethod5035purgehead.
2. Usingthesyringeport,inject5mLoforganicfreereagentwater,internalstandards,andsurogatecompounds
into theVOAvial.
3. Begin theanalysisbypressing theRUNbuttonor thecomputerkeyboardspacebar.
Method 5030
Method5030stylepurgeand trap is for theanalysisofVOCs inaqueoussamples. Thispurgeand trap
technique is limited toanalytes thatpurgeefficientlyfromwater. 10mLof thesample isplaced inaclean test
tube. The test tubeheadspacewillcontainambientair,so ifyour laboratoryorworkarea isnotfreeofsolvent
fumes, theywillshowupinyourchromatogram.
Foraqueoussamples:
1. Inserta10mLaliquotof theaqueoussample intoaclean test tube.
2. Plug the test tubeopeningwithyour thumbandshake ituntil thecontents
areevenlydispersed.
3. Quicklyslide the test tubeover thepurgegas tubingand into thepurge
head,and tighten it inplacewith theknurledretainingnut.
4. Immediatelybegin theanalysisbypressing theRUNbuttonon thefront
of theGCorbypressing thespacebaronyourcomputerkeyboard.
Formediumconcentrationsoilsamples,doaquickmethanolextraction:
1. Place10gofsample intoacleanglasscontainer. Add20mLofmethanol
andshake it for1-3minutes.
2. Allow thesoil tosettle, thenpull100µLof the liquidsolution intoaglass
syringeandinjectitintothetesttubecontaining10mLoforganicfreereagent
water.
3. Plug the test tubeopeningwithyour thumbandshake ituntil thecontents
areevenlydispersed.
4. Begin theanalysis. Youmayneed todilute the samplemoreor less,
dependingon theconcentration.
Alwaysuseclean
samplecontainers
VOAvial
Test tube
Samplepreparationdependson thesample type,concentration,amount,etc. The thirdeditionofSW-
846from theEPA isaccessibleon theInternet. Go to http://www.epa.gov/epaoswer/hazwaste/test/main.htm
andclickon the 5000Series link todownloadMethods5030and5035.