Protection of a drinking water well from nitrate contamination by recirculating nitrate treatment well system /

drinking water well from nitrate contamination of

Bibliographic Details
Main Author: Wu, Keng-Chung, 1964-
Format: Thesis Book
Language:English
Published: [Place of publication not identified] : [publisher not identified] ; 1994.
Subjects:
Online Access:http://proxy.library.tamu.edu/login?url=http://proquest.umi.com/pqdweb?did=741966051&sid=1&Fmt=2&clientId=2945&RQT=309&VName=PQD
Description
Summary:drinking water well from nitrate contamination of
groundwater is presented. A recirculating nitrate treatment
well system is proposed in which groundwater is drawn into
the well, denitrified in the treatment chamber, and returned
to the top of the aquifer. Well hydraulics were
experimentally examined in a two-dimensional aquifer model,
and ambient groundwater velocities of I to 3 m/day were
simulated in combination with well recirculation rates of 25
to 200 mllmin. An on-line feed control system was developed
for testing the treatment barrier associated with well
recirculation and biological identification. The impacts of
carbon feed, groundwater flow, nitrate loading, and well
recirculation on the performance of system operation were
also investigated. Hydraulic problems identified with
experimental apparatus included blow-through of contaminant
at the well intake by high ambient groundwater velocities
and submergence by the well hydraulics of depth-distributed
contaminant plumes without interception. The problems
associated with biological denitrification were found to be
possible permeability loss by screen fouling and blinding of
soil pores by overfeed of carbon. These identified problems
were corrected by maintaining a greater well recirculation
rate and adjusting carbon feed at stoichiometric rabo of
nitrate load to the well.
This study has demonstrated that the recirculating nitrate
treatment well system may be a feasible process for
protecting drinking water wells from groundwater
contamination in a sandy unconfined aquifer. Experimental
results provide guidance in identifying affecting
parameters that could possibly affect the performance of
the treatment system. On the basis of experimental
results, the procedures of system design were also
developed for evaluating the feasibility of the proposed
methodology.
Item Description:Vita.
"Major Subject: Civil Engineering".
Physical Description:xiii, 175 leaves : illustrations ; 28 cm.
Issued also on microfiche from University Microfilms Inc.
Bibliography:Includes bibliographical references.