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About:
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Water Well Maintenance and Rehabilitation
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The purpose of the study to obtained <a
href="http://www.chinascreenpipe.com/water-well-screens/" target="_self">water well
screens </a>opening size and gravel packs size, and to access within the groundwater
inter through the aquifer to the well screen and prevent running sand from entering
the well. The use of properly designed screen and gravels are important and this paper
is an important reference for the design of groundwater wells. In this study, the
purpose of the circle method is to design water well and the benefits of sand control.
The determination of screen slot size and its variation in the opening is often a
major aim of hydrogeological studies. However, measurement of hydraulic conductivity
(K) at a high spatial resolution in sedimentary aquifers is a challenge. One commonly
used approach is to estimate slot size from grain size analysis. The objectives of
this study are to compare between curve of grain size analysis, bar graph and circle
method used applied different formulas for the determination of slot size from grain-
size data and to evaluate how well this method predicts slot size and gravel pack.
Correlation between the mechanical analysis curve, bar graph and the circle methods
were found for the used applied different formulas. Based on circle results, the
applied circle formulas appear to be suitable for an initial assessment of aquifer
properties. However, considering the difference in calculated aquifer parameter
values, results are smaller significantly and reliable for the high analysis of
aquifer materials.
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The well screen is the component of a well which provides an opening through which
water enters the well casing from the aquifer, as well as stabilizing the material in
the “near-well zone” and preventing it from entering the well. Screens may be
constructed with a variety of different materials and designs, as appropriate to the
design of the well and its aquifers. Typical types of screen are:
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Horizontal <a href="http://www.chinascreenpipe.com/water-well-screens/bridge-
slot-screen/" target="_self">bridge slot screen</a>, a pipe-based well screen with
punch-formed downward facing louver-shaped openings.
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Continuous wire wrap screens, manufactured by wrapping shaped wire around an
internal array of rods.
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Bridge slot screens, produced by rolling and welding perforated steel plates or
sheets.
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Machine-slotted (milled) screens, manufactured by milling casing with axially
oriented precision cutters.
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Well casing perforated in place with a mills knife or a hydraulic perforator
lowered down the cased borehole.
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Different <a href="http://www.chinascreenpipe.com/water-well-screens/wedge-wire-
screen/" target="_self">wedge wire screen </a>may by evaluated for a particular well
design based on the material, size of perforations, percent of open area, cost,
susceptibility to corrosion, and collapse strength. A properly designed screen allows
sand-free water to flow into the well with a minimum drawdown.
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As a water well ages, the rate at which water may be pumped (commonly referred to
as the well yield, flow or performance) tends to decrease, especially in wells that
were not properly developed when first drilled. This fact sheet briefly describes
common well problems and discusses prevention and rehabilitation measures.
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Water Well Maintenance
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Water wells require regular maintenance to ensure adequate water flow and
continued drinking water safety. To ensure water quality, well water should be tested
annually for total coliform bacteria and E. coli bacteria by a state accredited
testing laboratory.
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Every three years, additional testing is recommended for pH and total dissolved
solids as well as tests related to land uses occurring or expected to occur within
sight of the well. Additionally, if there are obvious stains, tastes, or odors in
water, seek testing that will help identify the source of these symptoms.
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Water wells should also be inspected annually for obvious signs of damage or
contamination. Be sure the area within 100 feet around the <a
href="http://www.chinascreenpipe.com/water-well-screens/continuous-slot-screen/"
target="_self">continuous slot screen</a> is clear of debris or items that might
pollute the water supply.
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Get the well professionally inspected by a water well contractor every ten years.
Keep all records related to the water well including:
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Water well completion report or log (if you have it) which should include
information such as water well depth, date drilled, construction (including casing
specifications, grouting and screen), and water well yield or flow rate in gallons per
minute (gpm)
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Water quality test reports
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Past inspection reports
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Invoices from work done by water well contractors (including pump replacement)
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Water treatment equipment warranties, invoices and manuals
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To find some of this information you can check with the Pennsylvania Department of
Conservation and Natural Resources (PA DCNR) Pennsylvania Groundwater Information
System (PaGWIS) or contact a local well driller.
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