RAPID MULTIPLE CHOPSTICK WATER SAMPLER

A FREE FALL WATER SAMPLER BASED ON THE CHOPSTICK WATER SAMPLER BAG WILL BE DEVELOPED. THIS PORCUPINE SAMPLER WILL BE CAPABLE OF TAKING UP TO 36 THREE LITER WATER SAMPLES AT DEPTHS CONTROLLED FROM THE SURFACE, OR AT DEPTHS DETERMINED BY AN INTERNAL CONTROLLER. THE SAMPLE WILL BE OPTIMIZED FORMINIMUM TRAVEL TIME FROM THE SURFACE TO THE BOTTOM AND BACK SO THAT THE CURRENT FOUR HOUR ON STATION TIME FOR SAMPLES TO5000 METERS DEPTH CAN BE SUBSTANTIALLY REDUCED. THE RAPID SAMPLING CYCLE AND THE ELIMINATION OF THE NEED FOR AN ELECTROMECHANICAL CABLE WILL GREATLY REDUCE THE COST OF SAMPLING. PROVISION WILL BE MADE TO INCORPORATE OTHER INSTRUMENTATION SUCH AS CONDUCTIVITY TEMPERATURE DENSITY (CTD) OR DROPSONDE CURRENT MEASUREMENT ONTO THE SAMPLER. THE PORCUPINE SAMPLER WILL ALSO OFFER ADVANTAGES FOR CONVENTIONAL SAMPLING USING ELECTRICAL CABLE. TO MAXIMIZE THE POTENTIAL UTILITY OF THE PORCUPINE SAMPLER. A PARALLEL STUDY WILL BE UNDERTAKEN TO EVALUATE CHARACTERISTICS OF VARIOUS PLASTIC FILM MATERIALS FOR THE WATER SAMPLING BAGS. A VARIETY OF PACKAGING MATERIALS CONSISTING OF LAMINATES OF PLASTIC FILM AND/OR METAL FOILS HAVE BEEN DEVELOPED THAT AREPROMISING AS SAMPLE BAG MATERIALS. SOME OF THESE MATERIALS PROMISE THE INERTNESS OF FLUOROCARBONS WITHOUT FREON CONTAMINATION, AND OTHERS INCORPORATING METAL LAYERS SHOULD PROVE USEFUL FOR SAMPLING HELIUM AND OTHER LIGHT GASES. SAMPLE BAGS WILL BE CONSTRUCTED FROM CANDIDATE MATERIALS ANDEVALUATED BOTH FOR TRACE FORMALDEHYDE CONTAMINATION, AND FORHELIUM AND NEON RETENTION.