Accession Number:

ADA621876

Title:

An Assessment of Aquifer/Well Flow Dynamics: Identification of Parameters Key to Passive Sampling and Application of Downhole Sensor Technologies

Descriptive Note:

Final rept. 12 May 2009-7 Nov 2014

Corporate Author:

TOLEDO UNIV OH

Personal Author(s):

• Britt, Sanford
• Martin-Hayden, James
• Plummer, Mitchell A.

Report Date:

2014-12-01

Pagination or Media Count:

96.0

Abstract:

Contaminant redistributive effects in wells are nearly always present. Complete mixing appears to be very common however, it is not universal. There is a continual balance between inflowing contaminant stratification where present and factors driving in-well mixing. Findings here imply common and very small drivers are responsible for slow but vigorous mixing relative to the residence time of water flowing through a typical well screen. Therefore, a tendency toward homogenization is anticipated to be common in field conditions. Most wells should experience strong redistribution effects, but some wells may maintain stratification or perhaps re-stratify differently from the surrounding formation. Ongoing technical transfer of these findings will promote better understanding in the environmental community that wells often represent a mixed flow-weighted average of the adjacent formation chemistry. This better understanding will yield cost savings in both short-term and long-term timeframes by accelerating the approval process for non-purge alternative sampling strategies, including passive sampling and in situ sensor technologies.

Descriptors:

• *AQUIFERS
• CONTAMINANTS
• DETECTORS
• FLOW
• PASSIVE SYSTEMS
• PURGING
• SAMPLING
• STRATIFICATION
• WATER WELLS

Subject Categories:

• Geology, Geochemistry and Mineralogy

Distribution Statement:

APPROVED FOR PUBLIC RELEASE