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Research
SAIF Water Wells has been monitoring two bored, water-table wells in Northumberland County since early 2007, taking regular readings (water depth, water temperature, etc.) in an effort to build a historical database of groundwater data. The following charts depict water-depth levels for the two locations. These charts are updated with every new reading. One thing to keep in mind when viewing these charts: The water level in bored wells is strongly influenced by local hydrogeologic conditions. The water level in your well may exhibit seasonal fluctuations that are greater or less than the ones illustrated here. Galilee United Methodist Church in Edwardsville Mount Olive Baptist Church in Wicomico Church
Construction Techniques for a Safer Bored Well
Note: Download the bookletwith photographs here (PDF, 496KB) Bored and hand dug wells frequently test positive for coliform bacteria. The following improvements in bored well construction and maintenance were identified in an effort to improve the ability of the well to keep water sanitary. In addition to sealing the points where contaminants enter bored wells, this design assures that service personnel will not have to go into the well. It also makes it easy for homeowners to chlorinate the well, or check for low water levels-without opening the well. A Safer Bored Well: Safer for the people who work on it. Safer for the people who drink from it. The Need: SAIF Water Wells has hundreds of laboratory reports on file showing bacteria in hand dug and bored water-table wells. A long search for causes led us to suspect construction standards. A list was presented to Robert Royall of Royall Pump and Well Company in Powhatan of the construction problems which we felt were entry ways for bacteria in water table wells. Mr. Royall took up the challenge to apply his expertise and also try some suggestions of SAIF Water to develop a well that would be a model for construction standards. Project Design: The well was bored near Kilmarnock, Virginia in August of 2008. Each stage of the construction process was documented, photographed, and observed by Health Department officials, a hydrogeologist, a microbiologist, a building contractor, an environmental health specialist, and Board members of SAIF Water. Soil samples were taken at each scoop of the boring rig. SAIF Water has conducted a series of follow-up samples for total and fecal coliform bacteria. The site was chosen because there were no environmental hazards such as nearby trees and because the old hand dug well on the property had failed several coliform bacteria analyses in spite of upgrades to the well. The water distribution system was equipped with an Ultra-Violet treatment system prior to construction.Driller's Completion Report. The original depth of the experimental well was 56 feet, but fill in occurred on the second day changing the floor to 46 feet with the water table at 29 feet 9 inches. The final flow rate was two gallons per minute. (It would take 6 hours to completely refill the well). The water was crystal clear.Laboratory analyses. The well is not perfect. In the six months following construction there has been no fecal coliform. Total coliform readings have normally been very low-between <1 to 29.4 MPN/100 ml. (Most Probable Number of bacteria per 100 mililiters estimated by laboratory). But following a major storm which dumped 4 inches of water on the area, there was a spike of 95.9 MPN/100ml.Evaluation of laboratory results. Virginia requires zero total and fecal coliform bacteria for the water to be considered potable. If the standard test were used showing only presence/absence of coliform bacteria this well would be considered contaminated and possibly condemned. However, the laboratory readings in Most Probable Number estimates show that, under Health Department regulations, the well would be considered acceptable for use with a treatment device. It is a dramatic improvement over the scores which SAIF Water had found for hand dug wells in the area which are frequently higher than the laboratory can estimate. Soil scientists suggest that the sandy soil which goes the entire depth of the well does not allow enough residence time for bacteria from rainfall to be oxidized before reaching the water table. The first tests were taken shortly after a storm dumped 4 inches of water in the area. This may exceed the natural treatment capacity of any bored well. (Some scientists feel that the total coliform standard is not a good measuring device and prefer to use fecal coliform analyses. Coliform bacteria is not harmful in itself but it is a convenient indicator organism which suggests the presence of other types of bacteria.)SAIF Water Wells, Inc. is a nonprofit church-related organization that has helped people without water since 1989, primarily in Virginia's Northern Neck Counties. SAIF Water has felt the need for research, community education and attention to the public policies that are related to our drinking water.Both Royall Pump and Well Company and SAIF Water Wells are members of the Virginia Water Well Association. Contact Robert W. Royall Rev. Gayl Fowler
Health Risks of Bored & Hand-dug Wells
Approximately 3,486 wells (1,559 in Lancaster County and 1,927 in Northumberland County) are in use that were built before the Health Department instituted stricter safety standards for the construction of large-diameter bored wells. In addition, many wells are adjacent to or in the midst of farm fields that are regularly treated with pesticides. SAIF Water began research on large bore wells with the following questions in mind:
In a country that has strict standards for drinking water from public systems, thousands of wells are rarely treated or tested because they are "private". Sporadic disinfection by the owners may be woefully inadequate. The Jessie Ball duPont Fund awarded a three-year study grant. The SAIF team headed by hydrogeologist Frank Fletcher with the assistance of geologist Lynton Land, physician Sherrilynn Hummel, epidemiologist Alfred Pheley, and SAIF Water Chairman Gayl Fowler. Technical support was awarded by Southeast Rural Community Assistance Project for lab tests and an environmental-pollution specialist. Rosalie Coultrip, Environmental Health Specialist for Northumberland County's Health Department, served as a consultant. Partners included the Northern Neck Free Health Clinic, staff of Rural Infant Services, the Rappahannock Area Health Education Council, a representative of the Northumberland County School Board and Social Services Department, Northumberland Association for Progressive Stewardship, and a toxicologist. A plain language report of our findings on large-bore (water-table) wells is available by contacting the SAIF Water office by telephone at 804-580-2079 or email at saif (at) crosslink (dot) net.
SAIF Water has initiated a public-private partnership with the Virginia Department of Environmental Quality (DEQ) to encourage research on our artesian acquifers. One outstanding result is the construction of the first two wells for a monitoring station on the Northern Neck. By comparison, the Eastern Shore has fifty observation well sites. The Surprise Hill station being developed in Northumberland County will need nine wells and be the first of three or four observation sites to collect real-time data. Telemetry equipment will be installed to transmit data every fifteen minutes to a database of the U.S. Geological Survey, which can be accessed by anyone. SAIF also researches individual cases, where homeowners have problems with their artesian wells. Field trials of treatment equipment to address iron and sulfur problems are being conducted. Many artesian-well problems can be avoided by consulting U.S. Geological Survey's Professional Paper 1731, which maps the various aquifers in the Northern Neck area.
The Leetown project began as an effort to find a way to treat greywater so that elderly people whose land did not perc well enough for a traditional septic system might at least be able to have water in their kitchens. SAIF Water had tried composting toilets and was intrigued by the flowerbox treatment system in place at the post office in La Plata, Maryland. Supervising engineer William Lowrey and Design Engineer Tom Kinney, volunteers with the SAIF Water Committee, researched alternatives and met with professionals in Maryland and the Tennessee Valley Authority. They then planned a wastewater treatment system for four houses in a neighborhood called Leetown which included: House 1 - a single cell constructed wetlands bed for greywater. House 2 - a flower box treatment for greywater. House 3 - a 2 cell constructed wetlands (one lined and one unlined bed) combined with a sandfilter for combined grey and black water House 4 - a recirculating sandfilter which channeled the effluent to the wetlands beds at house 3. All four homes were connected with a pipeline to the wetlands beds at house 3 and an overflow tank which could be pumped in case the system failed. Bond was posted by Lancaster County to cover any emergency pumping. The system was constructed by volunteers and Bibbens Construction Company under the supervision of Cullen Walker beginning October 1, 1993. Construction was completed and first test results began in January 1994. Monitoring wells were sited and a monitoring program was outlined for SAIF Water by the Wastewater Division of the Virginia Department of Health. Volunteer oversight was provided by William Crawford, M.D., retired medical director for the Eastern Region of the Virginia Department of Health and a member of the SAIF Water Committee. A wastewater consultant is presently reviewing the lab tests and other data collected at these sites.
SAIF Water has not been satisfied with composting toilets and no longer installs them. Although several homes have managed very well, there seems to be no way to predict whether a homeowner will be able to maintain them properly. Service providers were extremely hard to get.
Downloadable files in PDF format. If you don't have Acrobat Reader to read PDF files, it can be downloaded free of charge here. Aquifers of the Northern Neck, Virginia (361KB) Groundwater Flow Models (13KB) Photo Summary - Remediation of Shallow Wells (375KB) Groundwater Supply at Risk of Depletion Frank W. Fletcher, PhD, PG, Hydrogeologist, Reedville In his recent editorial (The Parched East, May 30, 2007), John R. Wennersten forcefully drew attention to the water problems facing the people of the Atlantic seaboard, but his focus on surface water supplies failed to stress the importance of groundwater in any plan for the water needs of the future. ------------------------------ Aquifers of the Northern Neck, Virginia (361KB)
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