Groundwater Control Since 1934

Coal Ash Dewatering Solutions

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Groundwater Control Since 1934

WE ARE GRIFFIN Dewatering Griffin has provided service and equipment to the construction dewatering and groundwater pumping market since 1934 gaining the respect of Griffin’s clients by solving their groundwater problems.

Pumps & Equipment Griffin Pump has over 80 years experience in manufacturing innovative equipment that is a direct result of field experience.

Filtration and Treatment Griffin offers treatment systems for any application using the appropriate technologies to best treat the water on our client’s jobsite.

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Griffin Dewatering has the engineering capabilities, the experienced personnel and the wide range of equipment and services needed to handle complex dewatering challenges.

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Mission Statement

Founded in 1934, Griffin Dewatering is the leader in dewatering and groundwater control. We are guided by an unwavering commitment to our core values and we aim to lead the dewatering and groundwater control industry through a continual improvement process, leading to our profitable growth. We diligently cultivate relationships with clients to help determine their dewatering, groundwater control and pumping related needs, tailor an engineered cost–effective, first–class solution to meet the needs and deliver the solution in a safe, timely, courteous and professional manner. We recognize that our past and future success heavily relies on the efforts of our empowered, knowledgeable, experienced, dedicated and valued employees. We constantly strive to build lasting relationships with our clients and stakeholders through integrity, respect and performance providing a solid foundation for all of our projects.

Your Partner in Groundwater Control

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Core Values

• Integrity We know and do what is right. We follow rules and procedures, are honest, keep our commitments, and continually give our best effort, while treating each other and our clients with dignity and respect.

• Empowered We are diligent leaders who encourage people to reach their potential. We attract, develop and retain the best talent for our business. We create exciting opportunities for ourselves and our clients by growing intellectually.

• Safety We strive to be accident free. We will not compromise our health and safety. We will provide a safe work environment through proactive training, focus, and recognition. Our health and welfare is critical to our success. We look out for ourselves and others.

• Accountability We take responsibility for our own actions and measure our success by our clients' success. We promote accountability through honest, open and professional communication, resulting in great relationships and teamwork.

• Quality We provide outstanding products and unsurpassed service that, together, deliver premium value to our customers. Our actions and personal standards reflect our mission of being the best dewatering and groundwater control company. We focus on delivering desired results within established timeframes.

Your Partner in Groundwater Control

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Coal Combustible Residuals: Challenges and Solutions to Dewatering and Disposal • Fly ash has low/no compressibility • Stabilization of fly ash for dry excavation results from

reduction of pore water pressure, thus increasing cohesion • Key success factors for excavation dewatering:

• Field permeability testing of fly ash in situ • Proper engineering analysis of permeability, flow conditions and

expected drawdown • High intensity of dewatering by using closely spaced wickpoints that

operate without disruption • Preventing recharge from aquifers or runoff • Effective filtration/treatment of discharged water

Ash Pond Dewatering

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Lowering the water content of ash pond materials by pre-drainage increases coal ash cohesion and stability. This allows for vertical cuts to be made for large scale excavation with conventional excavation equipment.

The primary methods of ash pond dewatering are:

• Wickpoints • Deep Wells • Well Points • Eductors • Sumping

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Three Distinct Sources of Water

Ash Pond Dewatering

• Impounded/free water which lies on top of the ash and comes from precipitation and/or sluicing.

• Groundwater which may intrude into the bottom of the ash.

• Interstitial water which lies in the pore spaces of the ash.

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Staging between the 3 pumping systems is a key factor in preventing the potential for leachate entering the groundwater.

Groundwater Control Since 1934

Kingston Fossil Plant Ash Pond, Kingston NC

Coal Combustible Residuals: Griffin’s Approach to Engineered Dewatering Solutions for Ash Pond Excavations

• Groundwater Modeling

• Engineering and Design

• Dewatering Systems • Pumps and Equipment

• Filtration and Treatment

• Maintenance and

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SEEP 2D Griffin utilizes two dimensional seepage analysis in order to calculate the flow lines, constant head lines and water table for specific projects like dam seepage and cutoff wall dewatering.

Using MODFLOW helps analyze the 3D models for the dewatering system. The cone of depression resulting from dewatering can be simulated and shown in 3D view. The flowrate required for drawdown at each jobsite can be estimated for each well location.

MODFLOW

10 Modeling is used to develop a cost–effective plan to manage the 3 water sources

• Dewatering Systems Design (Permanent and Temporary)

• Aquifer Testing (Pumping Tests and Slug Tests)

• Uplift Pressure Calculation / Relief Well Design

• Recharge Well Design

• Dewatering Submittals

• Developing Dewatering Specifications Soil stratigraphy, using GMS Borehole Module, based on the available borehole data. Case study: Treatment Facility in Norfolk, VA

Engineering and Design

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Ash Pond Dewatering

Three Part Solution

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Staging between the 3 pumping systems is a key factor in preventing the potential for leachate entering the groundwater. Treatment of all water sources is part of the Griffin solution.

SilterMops for free water pumping

Dewatering Systems

• Geotextile filter assembly

• Tailored to site conditions

• Suspended solids control

• Coupled with reliable

Griffin pumps

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Pumps and Equipment

Full Line of Dewatering and Treatment Systems

Dewatering Systems

• Deep Well Systems

• Wellpoint/Wickpoint Systems

• Eductor Systems

• Open Pumping/ Sumping

• Filtration and Treatment

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Wellpoints

Deep Wells

Eductors

Wickpoints

Dewatering Systems

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• Installed in the ash to remove the interstitial water

• Grid pattern due to low permeability of ash

• Results in stable ash

• Griffin wickpoints are constructed using formed polystyrene core with a nonwoven spun bonded filter fabric

• The core provides an uninterrupted path for water to flow

Wickpoint System

Dewatering Systems

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The right equipment for the job

Dewatering Systems

• Griffin trained crews

• Men, materials, methods and machines tailored to the project

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Filtration and Treatment

Griffin has extensive experience treating groundwater and offers field tested solutions and equipment for our client’s water treatment requirements.

Griffin offers systems to address standard groundwater issues such as: • Total suspended solids • Nuisance mineral removal (Iron, manganese, etc.)

• Hardness

• pH

• Hydrogen sulfide

• Heavy metal removal

• Radium

• Radon

• VOC contamination 19

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Maintenance and Operation

Griffin has available specialists trained to operate, maintain, and repair a wide range of dewatering and treatment systems and equipment.

Griffin’s core dewatering business, includes construction, dewatering, systems integration, operation and maintenance.

Kingston Fossil Plant Ash Recovery Project Tennessee Valley Authority 2012

Case Study

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Griffin was contracted to lower water in ash more than 10’, creating a stable working platform and allowing a barrier wall to be constructed.

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Please visit our website for more details at: www.griffindewatering.com

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