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liquid being sampled. Though the device can be used to skim the sutfac�, or obtain is t e gate samples of all the water in the pit, the most common applieat on foe the device is the collection of samples of that water which is below the surface and petroleum fuel contami- nants that may be floating on the surface. Requests for subsurface samples are usually made by regulatory agent' inspectors seeking information to determine if there are large amounts of dissolved constituents in the main body of water(indicating that lost fuel has been in contact with the water for a sufficient length of time to allow a significant discharge of benzene and other soluble compounds into the water)or if a petroleum£ilm an the water may be only the result of fuel Contasru- nated soil falling into the pit in the course of rite present tank excavation work. The fre- quency of requests for sampling of this sort in several San Francisco Bay area counties lead to the development of the current version of the device and its issue to all our field personnel. The "subsurface" designation indicates that the device was used in the following mar .=cr: The device was lowered into the body of water with the sample container closed against the intrusion of liquid; the: sample contai:,cr was not opened until it was below the surface of the liquid and any free petmieu:r, that might be floating on the surface; the sample container was opened below the surface and allowed to fill with sul,surface liquid; tl:e device was closed before being trought back up through the surface of the body of -'iter. The ordinary "water mrnp'.e" dcsibnation indicates that the devic wss used without a.1y attempt to collect subsurface water. Ln this application the device is lowered into the water with the seal open so as to include tx til the surface and substufaCC water in an agf -gate sample. In this application the device duplicates the functioning of another EPA device which consists of a simple bottle or Cf to jar attached to a pole. Ordinary "writer samples" may also be collected in trailers •.v hich are made of either acrylic plastic, Teflon, or stain- less steel. These, however, arY usually designated `bailer" samplas. Sample Containers Our firm uses new sample com:>.ners of t`;e type specified by either EPA or the F.WQCB for the collection of sarTI's at sites wunderground storage tanks are involve Water samples are contained in 40 rli voladie organic rtralysis vials (VOAs) when analysis for gasoline and similar light volatile cornu,;;nds is intcndvd. These containers are prepared according to EPA SVI 846 and wird co:ta.in a small amount of prescrvaave when tilt, analysis is for TPH as gasoline or EPA ,;C?. Vials intended for M 601 analysis and EPA 624 GCMS prnredures are not presc:zed. Closure is :=ccampiis}.cd vzth an aper, herded. (syringe accessible) plastic scre,v cap 't r gilt down o;r tcp ,),a Teflort faced septim which is used to seal the sampic without brad }.ace. Water samples intended for scrtavol 'e end nonvolat It anslysis such as tool oil and grease (MG) and diesel ("ITH-HBF) r -oliected ane t,ansported in properly prep -od new glass liter bottles Dark amt- Cl t, °s used in t}'r rna:tufaCtu;=- of tilts"_ [!&nt to rCduce any advent cffe -.t --� U. �> r:i'� S!)Iilrgilt. Antsnucroloi:.= i`cservanve M:,x be. added to the sarrpit liquid i; a vl(_Jing erne is� exl)P.C,td p ti,r to Closure is accornphshe3 with 2 iter, ; yl uC screw cap.