HYDROGEOLOGY AND GROUND-WATER QUALITY OF NORTHERN BUCKS COUNTY, PENNSYLVANIA by Ronald A. Sloto and Curtis L Schreftier ' U.S. GEOLOGICAL SURVEY Water-Resources Investigations Report 94-4109 Prepared in cooperation with NEW HOPE BOROUGH AND BRIDGETON, BUCKINGHAM, NOCKAMIXON, PLUMSTEAD, SOLEBURY, SPRINGFIELD, TINICUM, AND WRIGHTSTOWN TOWNSHIPS Lemoyne, Pennsylvania 1994 U.S. DEPARTMENT OF THE INTERIOR BRUCE BABBITT, Secretary U.S. GEOLOGICAL SURVEY Gordon P. Eaton, Director For additional information Copies of this report may be write to: purchased from: U.S. Geological Survey Earth Science Information Center District Chief Open-File Reports Section U.S. Geological Survey Box 25286, MS 517 840 Market Street Denver Federal Center Lemoyne, Pennsylvania 17043-1586 Denver, Colorado 80225 CONTENTS Page Abstract....................................................................................1 Introduction ................................................................................2 Purpose and scope ..................................................................... 2 Location and physiography ............................................................. 2 Climate...............................................................................3 Well-numbering system................................................................. 4 Borehole geophysical logging............................................................4 Previous investigations ................................................................. 6 Acknowledgments..................................................................... 6 Geology.................................................................................... 7 Precambrian crystalline rocks............................................................ 7 Cambrian and Qrdovician rocks ........................................................ 10 Rocks of the Furlong Klippe ...................................................... 11 Hardyston Quartzite............................................................. 11 Leithsville Formation............................................................ 11 Limeport Formation............................................................. 12 Allentown Dolomite............................................................. 12 Rickenbach Dolomite............................................................ 12 Mesozoic rocks .......................................................................12 Stockton Formation.............................................................. 13 Lockatong Formation............................................................14 Brunswick Group ...............................................................15 Limestone conglomerate ......................................................... 15 Quartzite conglomerate.......................................................... 16 Diabase........................................................................16 Alluvium and glacial outwash.......................................................... 16 Hydrology................................................................................. 17 Relation of geology to ground-water flow ................................................ 17 Unconsolidated sediments........................................................ 17 Diabase........................................................................17 Triassic sedimentary rocks........................................................ 19 Brunswick Group..........................................................20 Lockatong Formation ...................................................... 22 Stockton Formation........................................................ 26 Carbonate rocks.................................................................31 Crystalline rocks ................................................................34 Aquifer and well-construction characteristics ............................................. 34 Water-bearing zones............................................................. 35 Specific capacity ................................................................39 Well yield ......................................................................40 Transmissivity..................................................................40 Well depth and casing length .....................................................42 Water levels..........................................................................44 Water-level fluctuations..........................................................44 Depth to water..................................................................46 CONTENTS-Continued Page Hydrology Continued Water budgets........................................................................47 Cooks Creek basin...............................................................49 Tlnicum Creek basin............................................................. 50 Paunnacussing Creek basin....................................................... 50 Mill Creek basin.................................................................50 Tohickon Creek basin............................................................ 51 Recharge.............................................................................52 Ground-water/surface-water relations................................................... 53 Water use............................................................................64 Ground-water quality.......................................................................65 Physical properties....................................................................65 Inorganic compounds ................................................................. 67 Common ions................................................................... 67 Nutrients.......................................................................71 Metals and other trace constituents ................................................ 71 Volatile organic compounds ............................................................ 71 Radon...............................................................................74 Summary.................................................................................. 75 Selected references..........................................................................80 iv ILLUSTRATIONS Plate (In Pocketl Plate 1. Geologic map showing locations of selected wells in northern Bucks County, Pennsylvania Figures Page Figure 1. Map showing location of northern Bucks County study area...................... 3 2. Graph showing 1970-92 annual precipitation and 1961-90 normal precipitation at Lambertville, New Jersey ............................................... 4 3. Generalized geologic map of northern Bucks County ............................ 8 4. Sketch showing geologic cross-section of the Furlong fault, northern Bucks County ................................................................ 10 5. Caliper and natural-gamma logs of well BK-2202, Bridgetown Township, northern Bucks County .................................................. 18 6. Sketch showing wells tapping sedimentary rocks of Triassic age.................. 20 7. Caliper, fluid-temperature, and fluid-resistivity logs of well BK-2205, Solebury Township, northern Bucks County......................................... 21 8. Caliper and natural-gamma logs of wells BK-1493 and BK-1556, Nockamixon Township, northern Bucks County......................................... 22 9. Photographs from borehole television survey showing fractures penetrated by well BK-1343, Buckingham Township, northern Bucks County ................ 23 10. Caliper and natural-gamma logs of wells BK-1211 and BK-2481, Newtown Township, Bucks County................................................. 25 11. Caliper and natural-gamma logs of wells BK-2094 and BK-1850, Plumstead Township, northern Bucks County......................................... 26 12. Photograph from borehole television survey showing fracture penetrated by well BK-1347, Plumstead Township, northern Bucks County.................. 27 13. Caliper and fluid-temperature logs of well BK-1847, Plumstead Township, northern Bucks County .................................................. 28 14. Photographs from borehole television survey showing water-producing and water-receiving fractures penetrated by well BK-1847, Plumstead Township, northern Bucks County .................................................. 29 15. Caliper, natural-gamma, and single-point resistance logs of well BK-1838, Solebury Township, northern Bucks County ................................ 30 16. Caliper logs of wells BK-1839 and BK-1840, Solebury Township, northern Bucks County ................................................................ 32 17. Photograph from borehole television survey showing fracture penetrated by well BK-1839, Solebury Township, northern Bucks County.................... 33 18. Photograph from borehole television survey showing fracture penetrated by well BK-1838, Solebury Township, northern Bucks County.................... 33 19. Graph showing distribution of water-bearing zones with depth .................. 35 ILLUSTRATIONS-ConflniMd Page Figure 20. Caliper and natural-gamma logs of wells BK-1483 and BK-1484, Plumstead Township; northern Bucks County......................................... 38 21. Caliper and natural-gamma logs of well BK-1498, Nockamixon Township; northern Bucks County .................................................