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Common uses for hand operated drive samplers include all those applications where an undisturbed soil sample is dts'urd- Typical applications include Elie collection of soil samples from the bottom of a hand augerod boring,capillary zoae sampling where a drill rod is used to extend die sampler across an open pit to a se.ltcttd location on the wall of the excavation, and when sampling soil from the backhoe bucket that is too hard to allow a brass sample liner to be pushed into the soil by hand. In practice, the sampler is usually overdriven and then reuxcted. Then th.:: sampler is removed from the drill rods and hammer, opened, and Lite sampic contained in the brass sample liners removed. Samples to be analyzed aoie other meenvntal hazards az rd sampreated according to the same sample handling p Capillary Zone Soil Sample: The capillary zone is the soil horizon immediately above the surface of standing groundwater into which moisture is d.-awn by Capillary action. Capil- lary zone sampling is roost often requested in open pit and open utnch situations where lost petroleum products are evident or suspected. In these cases, it is reasoned that a sample of the capi!iary zone will demonstrate whether or not foci ::as been drawn up into the soil above the gmunJwater and, thereby, provide a rough indication of the volume and duration of the lost fuel condition. Engineers of the Region 2 RWQCB staff have specified Ire co:r_ sampling area as being from zero to six inches above elle surface of L.he standing perched water and no more than twelve inches back into the native soil from the lateral backfiilllnkttve- soi". interface. Tliere are two wcaknessrs which tend to inv lidatc capillary zo. ;amplirrg on the basis of inconsistent resuls. First, is the difficulty t:i,-ountz.red in locat;r.g dee true sauce of the perched water above which the capillary ej :csides. The rem;Fal of the tank and back- fill material tends to artificially lower the w :er in Litt irrvac die -trinity of the tank pit below the truce stL.nding waver level and mislead observers utter .r p to evaluate where the capillary zone is located. Second, the zone ti is a narrow boaon which is bordered on the top and bottom by soil which would net be expected to con'Mn nearly the concentra- tion of fuel hydrocar ens a s the capillary z,)rie prop err Collecting the correct material is complicated by conditions at die,site which .Isually consist of a broad excavation, with verdcal walls descending into a water f !e.l pit. Because of thcse conditions,dirt ct ap- proach to the sampling area is difficult,dangtrous,of impossib:e. Assuming that the sue and original Surface the purled water can t e determined, samples can be safely obtained by one. oft` following metho:s. n,.< backhoe bucket can be used to dig up a cegr.e 7i of the pit wall :-:_t Con;airs rte cap '_L:ry zone. and bring it up for inspection and sampling. An ahernativ: inCthod is to use section;of light weight drill rod and a drive sl.oc which contains a bra>, sample liner. This 'Lrsin can be extended across,the pit, positioned, and used to drive az undisturbed soil s mrilc. Subsurface Watcr Sample: Subsurface ,+tier s:_mplc•.s arc cb'--.:ed with a proprietary device which dap!icates the functioning,of eFeral t. PA,-coriun c ia'„ and industrial sam- pling devices. The device goes beyond the —7PA weighted bots- j,--vice, to include both the ability to posidcn the sample at an exact dc-A, (via an ex;enditic pole} and to securely re-