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Detection of interstate liquids pipeline leaks: Feasibility evaluation

Description: The approximately 200,000-mile fuel pipeline system in the US operates at flow rates up to 2.5 {times} 10{sup 6} gallons per hour (GPH). Most commercial technologies only provide on-line leak detection at about 0.3% of flow rate, i.e., about 7,500 GPH or larger. Detection of leaks at about 1 GPH or so is desirable both from a regulatory and leak-prevention standpoint. Brookhaven`s commercially-accepted perfluorocarbon tracer (PFT) technology for underground leak detection of utility industry dielectric fluids at leak rates less than 0.1 GPH, with new enhancements, will be able to cost-effectively detect fuel pipeline system leaks to about 1 GPH--3 orders-of-magnitude better than any on-line system. The magnitude of detected leaks would be calculable as well. Proposed mobile surveys (such as those used periodically in the gas pipeline industry) at about 110 to 120 miles per day would allow such small leaks to be detected at 10-ppb tagging levels (less than $1,500 of PFT for a 48-hour tag at the maximum transport rate) under worst-case meteorological dispersion conditions. Smaller leaks could be detected by proportionately larger tagging concentrations. Leaks would be pinpointed by subsequent conventional barholing and vapor analyses. There are no health nor safety issues associated with the use of the proposed technological approach nor any consequential environmental impacts associated with the proposed magnitudes of PFT tagging.
Date: October 20, 1998
Creator: Dietz, R.N. & Senum, G.I.
Partner: UNT Libraries Government Documents Department

Verification of subsurface barrier integrity using perfluorocarbon gas tracers

Description: Use of perfluorocarbon (PFT) gaseous tracers shows promise as an excellent means of demonstrating subsurface barrier integrity. The PFT technology has been applied at Brookhaven National Laboratory to evaluate the colloidal silica (CS) barrier installed during the summer of 1997. This program involved two separate experimental phases. In the first phase, PFTs were injected into the native soil for a period of one day in the region adjacent to the proposed location of the CS barrier. The information was used to confirm that diffusion is the rate controlling transport mechanism and measure in-situ diffusion coefficients for the tracers in the native soil. This information is useful in interpreting data from the second phase of this study. In addition, the monitoring data was used to estimate the leak (injection) location. In the second phase, PFTs were injected into the region contained by the CS barrier and data have been collected to evaluate the performance of the barrier. In the experiment three unique PFTs were injected with the aim of increasing the resolution of leak detection. Two regions which provided essentially no added resistance to flow as compared to the native soil were detected in the bulk of the CS barrier.
Date: March 1, 1998
Partner: UNT Libraries Government Documents Department

Subsurface barrier integrity verification using perfluorocarbon tracers

Description: Subsurface barriers are an extremely promising remediation option to many waste management problems. Gas phase tracers include perfluorocarbon tracers (PFT`s) and chlorofluorocarbon tracers (CFC`s). Both have been applied for leak detection in subsurface systems. The focus of this report is to describe the barrier verification tests conducted using PFT`s and analysis of the data from the tests. PFT verification tests have been performed on a simulated waste pit at the Hanford Geotechnical facility and on an actual waste pit at Brookhaven National Laboratory (BNL). The objective of these tests were to demonstrate the proof-of-concept that PFT technology can be used to determine if small breaches form in the barrier and for estimating the effectiveness of the barrier in preventing migration of the gas tracer to the monitoring wells. The subsurface barrier systems created at Hanford and BNL are described. The experimental results and the analysis of the data follow. Based on the findings of this study, conclusions are offered and suggestions for future work are presented.
Date: December 1, 1996
Creator: Sullivan, T.M.; Heiser, J.; Milian, L. & Senum, G.
Partner: UNT Libraries Government Documents Department


Description: Researchers from Brookhaven National Laboratory (BNL) tested perfluorocarbon (PFT) gas tracers on a subsurface barrier with known flaws at the Waldo test facility [operated by Science and Engineering Associates, Inc (SEA)]. The tests involved the use of five unique PFT tracers with a different tracer injected along the interior of each wall of the barrier. A fifth tracer was injected exterior to the barrier to examine the validity of diffusion controlled transport of the PFTs. The PFTs were injected for three days at a nominal flow rate of 15 cm{sup 3}/min and a concentrations in the range of a few hundred ppm. Approximately 65 liters of air laced with tracer was injected for each tracer. The tracers were able to accurately detect the presence of the engineered flaws. Two flaws were detected on the north and east walls and lane flaw was detected on the south and west walls. In addition, one non-engineered flaw at the seam between the north and east walls was also detected. The use of multiple tracers provided independent confirmation of the flaws and permitted a distinction between tracers arriving at a monitoring port after being released from a nearby flaw and non-engineered flaws. The PFTs detected the smallest flaw, 0.5 inches in diameter. Visual inspection of the data showed excellent agreement with the known flaw locations and the relative size of the flaws was accurately estimated.
Date: February 27, 2000
Creator: Sullivan, T.; Heiser, J.; Senum, G. & Millian, L.
Partner: UNT Libraries Government Documents Department

FY 2010 Second Quarter Report Evaluation of the Liu-Daum-McGraw (LDM) Drizzle Threshold Parameterization using Measurements from the VAMOS Ocean-Cloud-Atmosphere Land Study (VOCALS) Field Campaign

Description: Metric for Quarter 2: Evaluate LDM (Liu, Daum, McGraw) drizzle threshold parameterization for a range of cloud conditions by comparing the threshold function computed using measurements of cloud droplet number concentration and cloud liquid water content to measurements of drizzle droplet number concentrations and/or drizzle water content.
Date: April 4, 2011
Creator: McGraw, R; Kleinman, LI; Springston, SR; Daum, PH; Senum, G & Wang, J
Partner: UNT Libraries Government Documents Department

FY 2010 Third Quarter Report Comparison of Aerosol and Cloud Condensation Nuclei (CCN) Relationship Parameterizations with Data Collected During the 2008 VAMOS Ocean-Cloud-Atmosphere Land Study (VOCALS) Field Campaign

Description: Metric for Quarter 3: Report comparisons of aerosol/CCN relationship parameterizations with data collected in the first quarter and best parameterization for VOCALS data set.
Date: June 1, 2010
Creator: Wang, J; Daum, PH; Kleinman, LI; Lee, YN; McGraw, R; Sedlacek, AJ et al.
Partner: UNT Libraries Government Documents Department

Pre-Cloud Aerosol, Cloud Droplet Concentration, and Cloud Condensation Nuclei from the VAMOS Ocean-Cloud-Atmosphere Land Study (VOCALS) Field Campaign First Quarter 2010 ASR Program Metric Report

Description: In this, the first of a series of Program Metric Reports, we (1) describe archived data from the DOE G-1 aircraft, (2) illustrate several relations between sub-cloud aerosol, CCN, and cloud droplets pertinent to determining the effects of pollutant sources on cloud properties, and (3) post to the data archive an Excel spreadsheet that contains cloud and corresponding sub-cloud data.
Date: August 31, 2011
Creator: Kleinman, L. I.; Springston, S. R.; Daum, P. H.; Lee, Y.-N.; Sedlacek, A. J.; Senum, G. et al.
Partner: UNT Libraries Government Documents Department