Report on the feasibility of using isotopes to source and age-date groundwater in Orange County water district`s Forebay region

Davisson, M. Lee; Hudson, G. B.; Niemeyer, S.; Beiriger, J.M.; Herndon, Roy

doi:10.2172/266844

Cited by 5 publications

(8 citation statements)

References 5 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In these cases the simulated mean age of groundwater reaching well P6 was never greater than 6 years, certainly much smaller than the 17.7-year isotopically measured age. In addition, these simulations indicated that little, if any, groundwater in this well originated from the Santa Ana River, as has been suggested by the isotopic interpretations of Davisson et al [1996] (Plate 2).…”

Section: Calibration and Specification Of Hydraulic Conductivitysupporting

confidence: 62%

“…In addition, isotopic analyses are now being used to infer historical migra- tion patterns by estimating the composition, sources, and ages of groundwater sampled in production and monitoring wells near the spreading basins [Davisson et al, 1996[Davisson et al, , 1998Williams, 1997]. In this paper we will review some of the isotopic results and present a series of numerical simulations designed to examine residence times, historical or future migration pathways, and mixing and dilution processes in the system.…”

Section: Resource Management Challengesmentioning

confidence: 99%

“…Isotopic analyses have been used to estimate the composition aiad ages of groundwater in wells near the spreading basins [Davisson et al, 1996[Davisson et al, , 1998Williams, 1997]. Figure 4 shows the apparent ages of groundwater sampled in wells, as determined from measured tritium-helium ratios.…”

Section: Age Datingmentioning

confidence: 99%

See 2 more Smart Citations

Analysis of groundwater migration from artificial recharge in a large urban aquifer: A simulation perspective

Tompson¹,

Carle²,

Rosenberg³

et al. 1999

Water Resources Research

View full text Add to dashboard Cite

Abstract. The increased use of reclaimed water for artificial groundwater recharge purposes has led to concerns about future groundwater quality, particularly as it relates to the introduction of new organic and inorganic contaminants into the subsurface. Here we review the development and initial application of a detailed numerical model of groundwater flow and migration in a region encompassing a large groundwater recharge operation in Orange County, California. The model is based upon a novel representation of geologic heterogeneity, which has long been known to influence local flow and transport behavior in the subsurface. The model and complementary series of isotopic analyses provide an improved scientific basis to understand flow paths, migration rates, and residence times of recharged groundwater, as well as to identify the source composition of water produced in wells near the recharge operation. From a management perspective these issues need to be confronted in order to respond to proposed regulatory constraints that would govern the operation of recharge facilities and nearby production wells. While model calibration is greatly aided by isotopic source and residence time analyses, the model also provides unique insights on the interpretation of isotopic data themselves. Isotopic estimates of groundwater age help discriminate between several equally acceptable simulations calibrated to head data only. However, the results also suggest that groundwater reaching a well spans a wide-ranging distribution of age, demonstrating the importance of geologic heterogeneity in affecting flow paths, mixing, and residence times in the vicinity of recharge basins and wells. BackgroundGroundwater is a significant source of drinking water in the United States and the rest of the world. Increased reliance on groundwater necessitates improved aquifer management with respect to understanding large recharge and discharge issues, planning rates of withdrawal, balancing demands of multiple users, and addressing water quality problems arising from industrial and agricultural contamination, artificial recharge, and saltwater intrusion.In California and elsewhere, artificial recharge practices are increasingly being used as a means •o augment groundwater availability and improve the overall reliability of water supplies. In this paper we are concerned with the fate and longterm water quality implications of artificial recharge in the large urban aquifer system underlying Orange County, California. We will explore the use of a detailed geologic modal of the aquifer system and numerical simulation as a basis to gain new scientific insight into these issues. We will also discuss how this approach has benefited from and contributed to similar efforts conducted from an isotopic analysis perspective. I and 3). Water recharged in the forebay can easily be drawn into the middle aquifers (Figure 2), as well as a shallow aquifer in the pressure zone and a much deeper "colored" water aquifer that is not used for production [OCWD, 1991]....

show abstract

Section: Calibration and Specification Of Hydraulic Conductivitysupporting

confidence: 62%

Section: Resource Management Challengesmentioning

confidence: 99%

See 1 more Smart Citation

Analysis of groundwater migration from artificial recharge in a large urban aquifer: A simulation perspective

Tompson¹,

Carle²,

Rosenberg³

et al. 1999

Water Resources Research

View full text Add to dashboard Cite

show abstract

“…There have been no conclusive monitoring or epidemiological studies relating to the introduction and fate of viruses into the OCWD aquifer system, although viruses derived from similar artificial recharge operations have been observed in a nearby aquifer in Los Angeles County 16 . As a means to assess compliance with the proposed regulations, however, isotopic and modeling analyses have been used in the Orange County system to infer migration patterns of groundwater and estimate the ages and sources of groundwater in production and monitoring wells near the spreading basins [17][18][19][20] . Figure 5 shows a figure from a modeling study 20 that shows approximate flow pathways from three production wells, labeled as 'P5', 'P6', and 'P7', back to their surface water sources.…”

Section: Aquifer Banking In Orange County Californiamentioning

confidence: 99%

“…Notably, from the simulation results, no water entering wells P6 and P7 is younger than 1 year in age, although more than half of the water entering well P5 is. As a result of these observations, a tracer test was conducted during a recharge event in nearby Anaheim Lake to see whether any "first arrivals" would appear in any of the various production wells surrounding the lake within a 1-year time period 17 . A small amount of a Xenon isotope ( 124 Xe) was introduced in the lake as the tracer.…”

Section: Aquifer Banking In Orange County Californiamentioning

confidence: 99%

SCIENTIFIC CHALLENGES FOR ENSURING CLEAN AND RELIABLE WATER FOR THE 21^ST CENTURY

Tompson¹

2005

International Seminar on Nuclear War and Planetary Emergencies — 32nd Session

View full text Add to dashboard Cite

Near-conservative behavior of 129I in the orange county aquifer system, California

Schwehr

Santschi

Moran

et al. 2005

Applied Geochemistry

View full text Add to dashboard Cite

Report on the feasibility of using isotopes to source and age-date groundwater in Orange County water district`s Forebay region

Cited by 5 publications

References 5 publications

Analysis of groundwater migration from artificial recharge in a large urban aquifer: A simulation perspective

Analysis of groundwater migration from artificial recharge in a large urban aquifer: A simulation perspective

SCIENTIFIC CHALLENGES FOR ENSURING CLEAN AND RELIABLE WATER FOR THE 21^ST CENTURY

Near-conservative behavior of 129I in the orange county aquifer system, California

Contact Info

Product

Resources

About

Report on the feasibility of using isotopes to source and age-date groundwater in Orange County water district`s Forebay region

Cited by 5 publications

References 5 publications

Analysis of groundwater migration from artificial recharge in a large urban aquifer: A simulation perspective

Analysis of groundwater migration from artificial recharge in a large urban aquifer: A simulation perspective

SCIENTIFIC CHALLENGES FOR ENSURING CLEAN AND RELIABLE WATER FOR THE 21ST CENTURY

Near-conservative behavior of 129I in the orange county aquifer system, California

Contact Info

Product

Resources

About

SCIENTIFIC CHALLENGES FOR ENSURING CLEAN AND RELIABLE WATER FOR THE 21^ST CENTURY