Feasibility Studies - A feasibility study is a systematic evaluation of possible abatement, mitigation, or remediation alternatives for an identified contamination issue. Feasibility analysis can also involve evaluation of applicable treatment options, execution of bench or pilot studies, development of innovative approaches, cost comparisons of effective technologies, consideration of operation and maintenance requirements, anticipated longevity, and overall project costs. A feasibility analysis is typically conducted between the delineation phase and the implementation/construction phase.

Remedial Design - Prism will work with you to solve your toughest engineering design challenges. Our design capabilities and experience span the complete range of environmental systems, wastewater treatment, and hazardous/toxic disposal facilities, using all accepted remediation technologies. Our services include all phases of project development from preliminary reports through the environmental impact study, permit application, design, financing, construction supervision, and operations assistance.

Combined with our construction management capability, Prism offers the following types of design engineering and/or construction practices:

Traditional Design - The entire design is completed and approved before initiation of the bidding and construction phases of the proposal.

 

Fast-Track Design - Some equipment with long delivery times is purchased early in the design phase of the project. All other design work is performed in the traditional manner.

 

Fast-Track Design/Build - Engineers and contractors work together, but as separate entities, on a very tight schedule in order to meet an accelerated implementation plan.

Turnkey - Engineers work with or for the contractor, who in turn works for the owner. The contractor does not normally provide detailed design information to the owner.

Excavation/Removal of Contaminated Material - Excavation of contaminated material, whether for off-site disposal, on-site treatment, or consolidation, remains a basic aspect of many remedial actions. Prism has performed numerous excavation projects involving a wide range of contaminants. Prism's experience also includes complex excavations that required extensive shoring and underpinning. Many of Prism's projects have required strict environmental and engineering controls to prevent the migration or emission of contaminants off-site. Prism's remediation experience includes a number of sites which involved the transportation and off-site disposal of hazardous waste and contaminated material. Prism provides full waste management services, including waste sampling and analysis, waste characterization, profiling, and manifesting.

Monitored Natural Attenuation - Natural attenuation relies on natural processes to cleanup or attenuate pollution in soil and groundwater. Natural attenuation occurs at most polluted sites. However, the right conditions must exist underground to clean sites properly. If not, cleanup will not be quick enough or complete enough. Scientists monitor or test these conditions to make sure natural attenuation is working. This is called monitored natural attenuation or MNA.

MNA works best where the source of pollution has been removed. For instance, buried waste must be dug up and disposed of properly or it can be removed using other available cleanup methods. After the source is removed, the natural processes get rid of the small amount of pollution that remains in the soil and groundwater. The soil and groundwater are monitored regularly to make sure they are cleaned up.

MNA can be a safe process if used properly. No one has to dig up the pollution, and nothing has to be added to the land or water to clean it up. But MNA is not a 'do nothing' way to clean up sites. Regular monitoring is needed to make sure pollution does not leave the site. This ensures that people and the environment are protected during cleanup.

In-Situ Treatment/Enhanced Bioremediation - In-Situ treatment typically involves an on-site injection system for chemical oxidation, bioremediation, and metals stabilization. Chemicals injected include hydrogen peroxide, potassium permanganate, sodium permanganate, magnesium peroxide, nutrients, acetic acid, lactic acid, sulfuric acid, calcium polysulfide, sodium metabisulfite, ferrous sulfate, and other chemicals.

Bioremediation is a process in which indigenous or inoculated microorganisms (i.e., fungi, bacteria, and other microbes) degrade (metabolize) organic contaminants found in soil and/or groundwater. Bioremediation is a process that attempts to accelerate the natural biodegradation process by providing nutrients, electron acceptors, and competent degrading microorganisms that may otherwise be limiting the rapid conversion of contamination organics to innocuous end products. Additionally, solid-phase products (e.g., oxygen releasing compounds [ORCs] or hydrogen releasing compounds [HRCs]) can also be used for enhancement and to increase the rate of oxidation or biodegradation.

Slurry Walls - Slurry walls are low permeability, vertical barriers constructed in the ground for the purpose of reducing the transport rate of liquids. Most commonly groundwater is the liquid of concern. Slurry walls used to contain contaminants are not usually designed for permanent retention, but rather as temporary barriers to allow some cleanup of the waste without it spreading through the groundwater. These structures can greatly increase the efficiency of a pump and treat system by reducing the volume of water that will enter the wells. The walls are typically keyed into a confining layer like clay or bedrock to prevent migration under them. In addition, some slurry walls can be designed to incorporate certain chemicals which will enhance the destruction of contaminants. These types of walls are typically referred to as chemical reactive barriers.

Permeable Reactive Barriers - Permeable reactive barriers (PRBs) are often referred to as iron filing walls, reactive barriers, funnel and gate systems, or passive treatment walls. PRBs can provide cost-effective, long-term solutions for many groundwater contamination problems. They are constructed underground to intercept contaminated groundwater flows and to provide preferential flow paths through reactive materials. As the groundwater moves through the reactive materials, contaminants are treated and transformed into harmless by-products.

After sufficient excavation has occurred, sand, zero-valent metals, chelators, and sorbents are proportioned, mixed, and placed into the excavation - typically through a tremie pipe. Enzymes can also be added to the trench to expedite biodegradation of the organic contaminants.