+ Site Statistics
+ Search Articles
+ PDF Full Text Service
How our service works
Request PDF Full Text
+ Follow Us
Follow on Facebook
Follow on Twitter
Follow on LinkedIn
+ Subscribe to Site Feeds
Most Shared
PDF Full Text
+ Translate
+ Recently Requested

Groundwater residence times in Shenandoah National Park, Blue Ridge Mountains, Virginia, USA; a multi-tracer approach



Groundwater residence times in Shenandoah National Park, Blue Ridge Mountains, Virginia, USA; a multi-tracer approach



Chemical Geology 179(1-4): 93-111



Chemical and isotopic properties of water discharging from springs and wells in Shenandoah National Park (SNP), near the crest of the Blue Ridge Mountains, VA, USA were monitored to obtain information on groundwater residence times. Investigated time scales included seasonal (wet season, April, 1996; dry season, August-September, 1997), monthly (March through September, 1999) and hourly (30-min interval recording of specific conductance and temperature, March, 1999 through February, 2000). Multiple environmental tracers, including tritium/helium-3 ( (super 3) H/ (super 3) He), chlorofluorocarbons (CFCs), sulfur hexafluoride (SF (sub 6) ), sulfur-35 ( (super 35) S), and stable isotopes (delta (super 18) O and delta (super 2) H) of water, were used to estimate the residence times of shallow groundwater discharging from 34 springs and 15 wells. The most reliable ages of water from springs appear to be based on SF (sub 6) and (super 3) H/ (super 3) He, with most ages in the range of 0-3 years. This range is consistent with apparent ages estimated from concentrations of CFCs; however, CFC-based ages have large uncertainties owing to the post-1995 leveling-off of the CFC atmospheric growth curves. Somewhat higher apparent ages are indicated by (super 35) S (>1.5 years) and seasonal variation of delta (super 18) O (mean residence time of 5 years) for spring discharge. The higher ages indicated by the (super 35) S and delta (super 18) O data reflect travel times through the unsaturated zone and, in the case of (super 35) S, possible sorption and exchange of S with soils or biomass. In springs sampled in April, 1996, apparent ages derived from the (super 3) H/ (super 3) He data (median age of 0.2 years) are lower than those obtained from SF (sub 6) (median age of 4.3 years), and in contrast to median ages from (super 3) H/ (super 3) He (0.3 years) and SF (sub 6) (0.7 years) obtained during the late summer dry season of 1997. Monthly samples from 1999 at four springs in SNP had SF (sub 6) apparent ages of only 1.2 to 2.5+ or -0.8 years, and were consistent with the 1997 SF (sub 6) data. Water from springs has low excess air (0-1 cm (super 3) kg (super -1) ) and N (sub 2) -Ar temperatures that vary seasonally. Concentrations of He and Ne in excess of solubility equilibrium indicate that the dissolved gases are not fractionated. The seasonal variations in N (sub 2) -Ar temperatures suggest shallow, seasonal recharge, and the excess He and Ne data suggest waters mostly confined to gas exchange in the shallow, mountain-slope, water-table spring systems. Water from wells in the fractured rock contains up to 8 cm (super 3) kg (super -1) of excess air with ages in the range of 0-25 years. Transient responses in specific conductance and temperature were observed in spring discharge within several hours of large precipitation events in September, 1999; both parameters increased initially, then decreased to values below pre-storm base-flow values. The groundwater residence times indicate that flushing rates of mobile atmospheric constituents through groundwater to streams draining the higher elevations in SNP average less than 3 years in base-flow conditions.

Please choose payment method:






(PDF emailed within 0-6 h: $19.90)

Accession: 019112402

Download citation: RISBibTeXText

DOI: 10.1016/s0009-2541(01)00317-5


Related references

Trees of Shenandoah National Park in the Blue Ridge Mountains of Virginia. 1967

Birds of the blue ridge mountains a guide for the blue ridge parkway great smoky mountains shenandoah national park and neighboring areas. Simpson, M B Jr Birds Of The Blue Ridge Mountains: A Guide For The Blue Ridge Parkway, Great Smoky Mountains, Shenandoah National Park, And Neighboring Areas Xvii+354p University Of North Carolina Press: Chapel Hill, North Carolina, Usa; London, England, Uk Illus Maps Xvii+354p, 1992

Residence times of ground water and spring discharge in Shenandoah National Park, Virginia. Abstracts with Programs - Geological Society of America 31(7): 331, 1999

Kinematic and temporal history of brittle deformation in Shenandoah National Park, Blue Ridge Province, Virginia. Geological Society of America 43.5, 2011

Using summit erosion rates measured with 10Be to assess landscape disequilibrium in the Blue Ridge, Shenandoah National Park, Virginia. Geological Society of America 42.1, 2010

Investigation of groundwater residence times during bank filtration in Berlin a multi-tracer approach. Hydrological Processes: 6, 788-801, 2008

The nature and sources of haze in the shenandoah valley blue ridge mountains area virginia usa. Journal of the Air Pollution Control Association 31(10): 1074-1082, 1981

Geomorphic influences on woody vegetation patterns at Dickey Ridge Center and vicinity, Shenandoah National Park, Virginia. Pennsylvania Geographer 38(1): 30-41, 2000

An 11-year record of groundwater age, chemistry and stable isotopic composition of discharge from Furnace Spring, Shenandoah National Park, Virginia. Geological Society of America 43.5, 2011

Improved approach for Lsc detection of 35S aiming at its application as tracer for short groundwater residence times. Journal of Environmental Radioactivity 208-209: 106022, 2019

Investigation of ground water residence times during bank filtration in Berlin; a multi-tracer approach. Hydrological Processes 22(6): 788-801, 2008

Reproductive success of Acadian Flycatchers in the Blue Ridge Mountains of Virginia / xito reproductive de Empidonax virescens en las montaas Blue Ridge de Virginia. Journal of Field Ornithology 76(2): 150-157, 2005

Mercury, Trace Elements and Organic Constituents in Atmospheric Fine Particulate Matter, Shenandoah National Park, Virginia, USA: A Combined Approach to Sampling and Analysis. Geostandards and Geoanalytical Research 32(3): 279-293, 2008

A 17-Year Record of Environmental Tracers in Spring Discharge, Shenandoah National Park, Virginia, USA: Use of Climatic Data and Environmental Conditions to Interpret Discharge, Dissolved Solutes, and Tracer Concentrations. Aquatic Geochemistry 20(2-3): 267-290, 2014

Multi-tracer investigation of groundwater residence time in a karstic aquifer; Bitter Lakes National Wildlife Refuge, New Mexico, USA. Hydrogeology Journal 18.2, 2010