Title : Patent Development Type : Antarctic EAM NSF Org: OD / OPP Date : November 07, 1991 File : opp93038 DIVISION OF POLAR PROGRAMS OFFICE OF THE ENVIRONMENT 202/357-7766 MEMORANDUM Date: November 7, 1991 From: Environmental Officer, DPP Subject: Environmental Action Memorandum (Potential Patent Development During Support of U.S. Antarctic Program in Area of Environmental Measurements) To: Files (S.7 - Environment) (S.7.1 - Wastes) Under the Special Five-Year Initiative for Antarctic Safety, Environment and Health, the Foundation's Division of Polar Programs has expanded significantly its efforts to enhance the environmental stewardship of the U.S. Antarctic Program (USAP). Part of the USAP's strategy in implementing the Initiative involves conducting antarctic environmental measurements (i.e., monitoring) to support environmental assessments and decision- making related to its operations. In Fiscal Year 1991, Idaho National Laboratory (INEL) began an effort to support such environmental measurements for the USAP. INEL's initial efforts have focused on reliable, scientifically-defensible measurement of wastewater effluent, and near station substrates (i.e., soils, snow, ice) and ambient air quality, parameters. While designing an effective wastewater effluent sampling and analysis strategy, INEL was confronted by the problem of obtaining a representative sample of the wastewater effluent for sampling and analysis of volatile organic compounds (VOCs). Traditionally, grab sampling is used to support analysis of VOCs; grab sampling of VOCs, however, tell little if the composition of the wastewater effluent changes with time. The U.S. Environmental Protection Agency specifies, therefore, composite sampling of effluents for most parameters. In line with this requirement, INEL developed an idea of how to collect 24-hour, composite wastewater effluent samples with negligible loss of volatile organics. Mr. Alan B. Crockett, Project Manager for INEL's USAP support work has submitted a patent application for this sampling approach developed in conjunction with the USAP's Environmental Measurements Program. -2- A summary of the approach follows: ================================================================= COMPOSITE WASTEWATER SAMPLING PROCEDURE SUITABLE FOR VOLATILE ORGANICS A patent application has been submitted to the U.S. Department of Energy for a method to collect a composite wastewater sample that can be analyzed for volatile organic compounds (VOCs). The objective of this method is to obtain a representative samples of wastewater over an extended period of time, typically 24-hours, without significant loss of VOCs. The method involves the use of a standard, commercially-available composite wastewater sampler, a sorbant trap and a sensing mechanism to shut the sampler off when the sample bottle is full. The wastewater sample is cooled during collection with an ice bath or in a refrigerated sampler. A sample bottle, typically of large size (i.e., 1 gallon or larger), is capped with access for an intake hose and a vent to the sorbant tube (Tenax, charcoal or another solid sorbent for VOCs). As liquid is pumped into the bottle at the rate expected to fill the bottle over the planned sampling period, gas in the bottle and some VOCs are displaced into the sorbant trap. The VOCs are sorbed and other gases are released to the atmosphere. When the liquid level reaches the cap and there is no more headspace in the bottle, the sampler is shut off by completion of a circuit between two exposed contacts. The sorbant tube is then capped at both ends to seal in the VOCs and volatile organic analysis (VOA) vials are filled following standard practices with the liquid content of the collection bottle. The liquid and sorbent tube samples are analyzed by an analytical laboratory and both contaminant fractions are combined and divided by the liquid volume of the sample bottle. This gives an average concentration for the sampling period. Ideally, a flow proportioned composite sampler is used to produce a mean value for the effluent stream. The current state of the art is to collect multiple grab samples for VOCs by filling 2-4 VOA vials with the effluent of interest at various intervals over a 24-hour period. At the same time, a 24-hour composite wastewater sample is collected for analysis of metals, semivolatile organic compounds and other wastewater parameters. Composite samplers are not used for volatiles due to the losses that occur during the normal compositing procedure. A grab sample is usually not representative of the waste stream. Alternately, many grab samples can be collected but at considerable extra effort in the field (multiple visits to collect samples) and much greater analytical cost. If only one grab sample is collected and the concentration in the effluent -3- varies considerably over time, the data are not representative and therefore meaningless. The method presented for this patent solves the problem of losing volatile organics during the collection of a composite sample. Thus the data are much more representative than one or more grab samples, field sampling time is minimized (i.e., no extra trips to collect multiple VOC samples). Also, analytical costs are, at worst, only doubled and, at best, greatly lower compared with taking many grabs. The proposed method still needs to be tested and, if successful, the results published in a peer reviewed journal. The experiment would involve spiking a TedlarTM bag of water (no headspace) with multiple volatile organic and using a composite wastewater sampler to collect a 24-hour composite sample from the bag. The source bag would be sampled several times during the 24 hours as well as well as the jug from the compositing device. These samples as well as the VOC trap would be submitted for analysis and the results compared. Three replications would be performed. Alan B. Crockett, INEL ================================================================= Sidney Draggan cc: Environmental Engineer, DPP Environmentalist, Antarctic Support Associates, Inc.