 |
|
|
||||
| Publications— Water-Resources Investigations Report |
By Arthur L. Baehr and Timothy J. Reilly
View the report in Portable Document Format (PDF) WRIR 01-4149 (14 KB)
Densely populated communities surround many of the larger lakes in northwestern New Jersey. These communities derive most of their water supply from wells. The lakes can be navigated by gasoline-powered watercraft, can be in various stages of eutrophication, may contain pathogens associated with bathing and waterfowl, and are periodically subjected to chemical applications to control aquatic plant growth. Another feature that contributes to water-quality concerns in lakeside communities is the widespread use of septic tanks.
Concentrations of methyl tert-butyl ether (MTBE), a gasoline oxygenate, in samples from Cranberry Lake and Lake Lackawanna ranged from 20 to 30 µg/L (micrograms per liter) and 5 to 14 µg/L during the summers of 1998 and 1999, respectively. These levels were persistent throughout the depth of the lakes when mixing conditions were present. MTBE concentrations in samples from the top 20 feet of Lake Hopatcong during summer 1999 were about 10 µg/L and about 2 to 3 µg/L in samples below 20 feet. The source of the MTBE in the lakes was determined to be gasoline-powered watercraft. Other constituents of gasoline--tertiary amyl methyl ether (TAME) and benzene, toluene, ethylbenzene, and xylenes (BTEX)--were detected in the lakes but at much lower concentrations than MTBE. Ambient ground-water quality at Cranberry Lake and Lake Lackawanna appears to be affected by the use of gasoline-powered watercraft. MTBE was detected in water samples from 13 of the 14 wells sampled at Cranberry Lake in fall 1998 and summer 1999. The wells were selected to monitor ambient ground-water quality and had no history of contamination. In ground-water samples collected during fall 1998, MTBE concentrations ranged from 0.12 to 19.8 µg/L, and the median concentration was 0.43 µg/L. In samples from summer 1999, MTBE concentrations ranged from 0.14 to 13.2 µg/L, and the median concentration was 0.38 µg/L. MTBE was detected in samples from four of the five wells at Lake Lackawanna in summer 1999;concentrations ranged from 0.05 to 0.19 µg/L. Lake/ground water interaction is a feasible explanation for the nearly ubiquitous presence of MTBE in ground water. The movement of water from lakes to wells is feasible because many static water levels and essentially all pumped water levels in the wells were below lake levels. Furthermore, diatom fragments were present in samples from the wells. Ambient ground water at Cranberry Lake also may be affected by septic-tank effluent, as indicated by the relation among concentrations of nitrate, boron, and chloroform. This result indicates potential vulnerability of the water supply to contamination by other chemicals and pathogens. Radon in ambient ground water is a concern throughout northern New Jersey. In particular, the median radon concentrations in ground-water samples collected from 14 wells at Cranberry Lake in 1998 and 1999 were 1,282 and 1,046 pCi/L, respectively. The median radon concentration in five ground-water samples collected at Lake Lackawanna in 1999 was 340 pCi/L. Although these values exceed regulatory levels, they are not high relative to radon concentrations measured in northwestern New Jersey. Eight wells in a neighborhood of Cranberry Lake with known MTBE contamination were sampled by the U.S. Geological Survey in summer 1998. MTBE was detected at concentrations greater than or equal to 40 µg/L in five of the wells. Concentrations of TAME, another gasoline oxygenate, were highly correlated with concentrations of MTBE; MTBE concentrations were about 10 times the TAME concentrations. In all samples, however, the concentrations of the BTEX compounds were less than 0.05 µg/L, and the sample from the most highly contaminated well, where the MTBE concentration was 900 µg/L, had no detectable BTEX.Abstract
Introduction
Purpose and Scope
Previous Studies
MTBE and Oxygenated Fuel
Acknowledgments
Methods of Investigation
Site Selection
Collection and Analysis of Samples
Lake-Water Quality
Cranberry Lake
Lake Lackawanna
Lake Hopatcong
Point-Source Contamination of Wells at Cranberry Lake
Ground-Water Quality
Comparison to Lake-Water Quality at Cranberry Lake and Lake Lackawanna
Lake/Ground-Water Interaction and MTBE Occurrence
Septic Tanks as a Source of Nitrate and Chloroform
Comparison to Ground-Water Quality in the New England, Piedmont, and
Coastal Plain Physiographic Provinces
Summary and Conclusions
References Cited
Appendix 1. Laboratory Schedules
Suggested citation:
Baehr, A.L., and Reilly, T.J., 2001, Water quality and occurrence of methyl tert-butyl ether (MTBE) and other fuel-related compounds in lakes and ground water at lakeside communities in Sussex and Morris Counties, New Jersey, 1998-1999: U.S. Geological Survey Water-Resources Investigations Report 01-4149, 86 p.
If you have Adobe® Acrobat® or Adobe® Acrobat®Reader® installed on your computer, you may view and print the PDF version of this report. Acrobat Reader, is a free download from Adobe Systems Incorporated.
View the report in Portable Document Format (PDF) WRIR 01-4149 (14 KB)
For more information about USGS activities in New Jersey contact:
Director
USGS New Jersey Water Science Center
810 Bear Tavern Road
West Trenton New Jersey 08628
Telephone: (609) 771-3900
Fax: (609) 771-3915
or access the USGS Water Resources of New Jersey home page at:
http://nj.usgs.gov/.
