WORK PLANS - Laserfiche WebLink

Home Browse Search

510:371 39211 Lid' H2OGEOL A GROUNDWATER CONSULTANCY Mr. Stephen L. Williams Project Manager for ASIA Construction Company, Inc. 17159 Los Padres drive Tracy, California 95376 456 P01 NOV 04 '94 15:29 RE: Soil samples from 687 East Locke£ord Street, Lodi, California. Dear Mr. Williams; This letter concerns the presence of low levels of toluene in soil, samples from 687 East Lockeford Street, Lodi, California. I suggest that the toluene originated in the adhesive of the tape used to secure the samples. All soil samples collected were processed according to generally followed practices. The ends of the soil sample tubes were covered with aluminum foil and a plastic cap plug was placed over the aluminum foil covered tube end. The ends of the aluminum foil and the cap plug were than secured with tape. This procedure is actually required by some agencies, whereas others are getting away from the use of the tape. The tape used was Scotch1" Super 33+ Vinyl Electrical Tape. The 3M Corporation's Electrical Products Division was called (800- 245-3573) and asked about the presence of toluene in this product. According to the telephone attendant 0.2% solvents are used in the formulation for the adhesive for this tape, a small portion of which is toluene. I have personally used this tape since 1981 for securing soil sampling tubes and have not previously experienced the detection of low levels of only toluene in samples. It is interesting to note that over the last ten years the price of this tape at Orchard Supply Hardware had risen steadily, reaching $4.49 per 22 yard roll for one purchased on December 31, 1993 and for rolls purchased on October 10, 1994 the price had fallen to $2.99. The price reduction suggests a possible change in manufacturing costs, though 3M maintains that "there have been no significant changes since y one." Sincerely, G 7�, Gary D. Lowe, R.G., C.E.G. Principal, Hydrogeologist P.O.6ox 2165 a Livermore, California 94551 0 510--373-9211