GZ GOLDBERG bull ZOINO amp ASSOCIATES INC GEOTECHNICALmiddotGEOHVOI=IOLOGICAL CONSULTANTS

April 1 1986 File No A-405404-cPC

Silreaim Site Trust Poat Office Box 169 Acton Massachusetts 01720

Attentions Mr James Rogers

Res GC ScreeningSUreaim Project

Gentlemen

Purauant to the us EPAbull requeat in a letter dated Januarl 28 1986 Goldberg-Zoino Aaaociatea Inc CGZAgt haa reviewe galchroaatograph CGC) acreening resultbull for the initial groundwateraaapling round at the Silreaim Site Data from the initial acreening round waa preaented within Deliverable Number 2 the Phaae One Sampling Plan aubmitted on February 14 1986 EPA requeated further characterisation of the GC reaults within their co nta on Deliverable Number 2

In reaponae to thil requeat GIA haa made the followingadditional tentative identificationbull of GC peaka reported with the initial aampling reaultla

e-ll BenleneAcetone (co-eluterl)C-12 _trachloroethylene c-14 Methyl ethyl ketone C-19 Chloro bensene

~he C-6 peak reported at aignificant peak heightbull in a number of aaplea correaponda to trana-12-dicbloroethylene in termbull of elution tiae However correlation bet en laboratory analyaeaby Roy r Welton and the GC acr ening data ia inaufficient to aupport even a tentative identification of tbia compound The COIIPlexity of the chroutogrua for the bullbull pl 1 from vella lOlA

71 gOOSQ

Silresim Site Trust - April l 1986 - File No A-405404 Page 2

1028 and l05A makes reliable identification of any of the other reported unknown peaks very difficult

It is noted that the screening data is intended primarily as a general indicator of the presence of absence or significantlevelbull of volatile organic contamination As such ita primaryvalue il to aid in bullelecting samplebull for more comprehensiveanaly1e1 during subsequent 1tagea of the project GZA feelbull that the data presentation format within Deliverable Humber 2 i1 adequate for tbil purpo1e

Hopefully the information provided above will fulfill EPAbull requireaent1 Should you have any questions on the data or should additional commentbull arise please call

very truly yourl

GOLDBERG-ZOINO ASSOCIATES INC

~~~~ Lawrence Feldman

LPadlv

Silresim Site Trust - April l 1986 - File No A-405404 Page 2

1028 and l05A makes reliable identification of any of the other reported unknown peaks very difficult

It is noted that the screening data is intended primarily as a general indicator of the presence of absence or significantlevelbull of volatile organic contamination As such ita primaryvalue il to aid in bullelecting samplebull for more comprehensiveanaly1e1 during subsequent 1tagea of the project GZA feelbull that the data presentation format within Deliverable Humber 2 i1 adequate for tbil purpo1e

Hopefully the information provided above will fulfill EPAbull requireaent1 Should you have any questions on the data or should additional commentbull arise please call

very truly yourl

GOLDBERG-ZOINO ASSOCIATES INC

~~~~ Lawrence Feldman

LPadlv