Advanced Groundwater Exploration and Development

Development of an Irrigation Supply ��Ϸ��ll for the ES-23 Elementary School, Loudoun County Public Schools

gzadan — Thu, 30 Sep 2021 16:43:41 +0000

Development of an Irrigation Supply ��Ϸ��ll for the ES-23 Elementary School, Loudoun County Public Schools gzadan Thu, 09/30/2021 - 12:43

Challenge

Emery & Garrett Groundwater Investigations (EGGI), a division of GZA, was hired to develop groundwater resources within the bedrock aquifer underlying the proposed Loudoun County ES-23 Elementary School project site. The purpose of this study was to assess the availability of groundwater resources on site to be used to irrigate ball fields being constructed at the ES-23 Elementary School project site. The property is approximately 13 acres in size.

Solution

EGGI conducted a detailed groundwater exploration program at the ES-23 Elementary School project site. The investigation included assessing hydrogeologic characteristics of the project site, geophysical investigations, selection of exploratory test well locations, installation of exploratory test wells, conversion of an exploratory test well into a larger diameter production well, pumping tests and collection of pumping test data, and water quality assessment.

Benefit

The results of this study indicated that sufficient groundwater resources are available on site to meet the anticipated irrigation water supply needs of the ES-23 Elementary School without causing adverse impacts to off-site groundwater users. An irrigation production well (��Ϸ��ll E23-A) was installed to meet the irrigation water needs of the school, which is estimated to produce approximately 100 gallons per minute (gpm) (144,000 gallons per day) which successfully meets all of our client’s needs. Irrigation ��Ϸ��ll E23-A was constructed in accordance with all Loudoun County Health Department and Virginia Department of Health requirements.

Advanced groundwater resource assessment
Groundwater exploration
Groundwater development
Groundwater testing �� yield and quality assessments
Groundwater protection

Water

Government

Water Resources

Groundwater Exploration and Development Jackson County Water & Sewerage Authority

gzadan — Thu, 30 Sep 2021 15:38:04 +0000

Groundwater Exploration and Development Jackson County Water & Sewerage Authority gzadan Thu, 09/30/2021 - 11:38

Challenge

Jackson County Water and Sewerage Authority (JCWSA) is currently assessing the potential to develop groundwater resources to supplement its existing water supply sources which are, in part, purchased from surrounding water systems. JCWSA recognizes the value of developing their own supplies of potable water and the importance of understanding where all potential groundwater resources within the County can be developed today.

Solution

Emery & Garrett Groundwater Investigation (EGGI)'s approach to groundwater exploration and development is based upon understanding the geologic environment from which groundwater resources are withdrawn. Our scientific investigation included the use of satellite imagery, aerial photography, on-site bedrock fracture fabric data, detailed geological mapping, an assessment of potential threats to groundwater quality, groundwater recharge review, and evaluation of existing wells.

Phase I of this groundwater development program focused entirely on selecting zones within the County considered to have a moderate to high potential for developing significant supplies of groundwater. Selection of these favorable groundwater zones was based upon the evaluation of many factors that directly influence the volume and quality of groundwater resources that can be withdrawn from bedrock aquifers.

Benefit

The results of this groundwater exploration program performed to date has served to identify 26 potential Groundwater Development Zones which the groundwater investigation team has selected as being “favorable�� for groundwater development.

Based upon the favorability of our findings during this investigation, we recommended that this groundwater exploration and development project proceed forward to Phase II. The County has approved Phase II investigations. The results of Phase II will include the selection of specific exploratory well targets on the properties selected by the County for further investigation. Ultimately, if favorable drilling targets are identified, the project will proceed with an exploratory drilling program and subsequent production well construction, testing, and permitting.

Use of advanced groundwater exploration methods
Selection of favorable Groundwater Development Zones
Geophysical surveys

Water

Government

Water Resources

Groundwater Monitoring Program Loudoun Water Community Water Systems

gzadan — Thu, 30 Sep 2021 15:31:39 +0000

Groundwater Monitoring Program Loudoun Water Community Water Systems gzadan Thu, 09/30/2021 - 11:31

Challenge

Emery & Garrett Groundwater Investigations (EGGI), a division of GZA, was asked to obtain the data necessary to effectively protect and manage Loudoun Water’s vital groundwater supplies that serve their community water systems. This was to include designing, developing, and implementing a Groundwater Monitoring Program at the following Community Water Systems: Beacon Hill, Creighton Farms, Elysian Heights, Raspberry Falls, Rokeby, and Selma Estates located in Loudoun County, Virginia.

Solution

Effective groundwater monitoring programs serve to protect the quality and quantity of groundwater resources to ensure that sustainable groundwater supplies can be maintained for future generations. The benefits of implementing a groundwater monitoring program are many and varied. These benefits include, but are not limited to, the following:

Provides an assessment of the changes that occur in groundwater storage in the bedrock aquifer and addresses whether long-term over-drafting (mining) of groundwater resources is occurring as a result of continued groundwater withdrawals.
Provides for the long-term determination of actual groundwater recharge rates that occur during both significant rainfall periods and drought periods.
Provides insights into the impact that rainfall events have on groundwater levels and groundwater quality. �� Provides an understanding of the impact that the lack of rainfall (drought) has on water quality.
Allows for an evaluation of the impact that drought has on groundwater levels and long-term groundwater resource availability and will help to provide the data necessary to develop a drought management plan.
Provides an assessment of changes in groundwater quality and quantity associated with changes in land use.
Provides an early warning system for the migration of groundwater contaminants that might be moving toward public supply wells.
Allows for an evaluation of long-term changes in Production ��Ϸ��ll capacity and pumping efficiency so that the Loudoun Water can properly manage, re-develop, and protect the costly infrastructure investment that has been incurred to develop groundwater supplies for the Community Water systems.

Benefit

For each community system monitored to date, it has been demonstrated that the wells are not depleting the bedrock aquifer capacity and that sufficient recharge is available to support the groundwater withdrawals. This monitoring program is necessary to determine if this remains the case under all climatologic conditions associated with climate fluctuations and climate change.

Assessment of bedrock aquifers
Groundwater monitoring
Groundwater protection
Drought management

Water

Government

Water Resources

Large Groundwater Withdrawal Permit Plymouth Village Water & Sewer District

gzadan — Thu, 30 Sep 2021 15:26:31 +0000

Large Groundwater Withdrawal Permit Plymouth Village Water & Sewer District gzadan Thu, 09/30/2021 - 11:26

Challenge

The Plymouth Village Water & Sewer District (PVW&SD) of Plymouth, NH, needed to identify, construct, and permit new groundwater supply well. The PVW&SD had for many years been seeking to develop additional drinking water resources to provide a redundant/supplemental source of groundwater for their existing water system. Other consultants had been previously hired to locate a new water source, but after spending more than $500,000 searching and drilling exploratory test wells, the Town chose to terminate those efforts and start over by hiring Emery & Garrett Groundwater Investigations (EGGI), a Division of GZA.

Solution

EGGI was retained by the PVW&SD to complete a detailed hydrogeologic analyses of the region to identify high yielding groundwater sources. This work led to the successful drilling, testing, and permitting of two new groundwater supply wells. This was performed in compliance with New Hampshire RSA 485-C:21, and Administrative Rules for Large Production ��Ϸ��lls, ��Ϸ��lls for Large Community Water Systems (Env-Dw 302), and Large Groundwater Withdrawals (Env-Wq 403). To meet these objectives, EGGI performed a Town-wide groundwater exploration program that served to locate favorable areas for groundwater development. Subsequently, geophysical surveys were used to select exploratory drilling targets and drill test production wells for sustainable yield and quality. The long-term sustainable production capacity of the unconsolidated aquifer was evaluated with a five-day, constant rate pumping test program. Based on the analyses of this pumping test data, the New Hampshire Department of Environmental Services (NHDES) approved the requested 500,000 gallons per day withdrawal rates from Production ��Ϸ��ll PWS-H8PW and Test ��Ϸ��ll PWS-H4TW as public water supply sources.

Benefit

The results of developing these new high yield wells has led Plymouth to be able to better serve their customers (including Holderness School) with higher quality water while providing substantial additional source capacity.

Advanced groundwater exploration program
Geophysics
Exploratory drilling
Production well drilling
Testing for sustainable yield and quality
Hydrogeologic report preparation
Groundwater protection
Permitting of groundwater resources

Water

Government

Water Resources

Advanced Groundwater Exploration and Development

Development of an Irrigation Supply ������Ϸ����ll for the ES-23 Elementary School, Loudoun County Public Schools

Challenge

Solution

Benefit

Groundwater Exploration and Development Jackson County Water & Sewerage Authority

Challenge

Solution

Benefit

Groundwater Monitoring Program Loudoun Water Community Water Systems

Challenge

Solution

Benefit

Large Groundwater Withdrawal Permit Plymouth Village Water & Sewer District

Challenge

Solution

Benefit

Development of an Irrigation Supply ��Ϸ��ll for the ES-23 Elementary School, Loudoun County Public Schools