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Environmental Due Diligence - Phase I Environmental Site Assessments

Banks, attorneys, businesses, and property owners alike have found StoneHill's pragmatic approach to completion of "all appropriate inquiry" suits their needs with respect to Superfund liability. StoneHill's Phase I Environmental Site Assessment reports effectively and rationally communicate key environmental liabilities regarding recognized environmental conditions and provide straight forward recommendations in perspective with the client's particular needs. More Information...

Phase II Site Investigation

If environmental concerns are identified on a property, "all appropriate inquiry" would include design of a data collection plan to gather adequate information concerning the extent and magnitude of contamination, physical and chemical parameters, and the potential impact to receptors, while minimizing costs to the greatest extent possible StoneHill has extensive experience with vapor intrusion assessment and mitigation. Assessing the risk to human health and the environment, and costs of cleanup, are evaluated to select appropriate remedial response activities as appropriate. More Information...

Site Remediation

StoneHill develops common sense remediation plans suited to each individual case and closely manages implementation of the remediation program. StoneHill specializes in vapor intrusion mitigation, and soil and groundwater remediation. StoneHill has has also completed numerous fuel oil spill remediation jobs in residential settings where sensitivity to the homeowner's concerns and minimizing remediation time and property disruption are strategic priorities. More Information...

PCB Investigation and Testing

Although federal regulations have prohibited the manufacture of Polychlorinated Biphenyls (PCBs) and controlled the phase-out of their uses since 1977, PCBs can still be found in older paints, caulking, oil, and electrical equipment. As such, PCBs are still quite prevalent and persistent in the environment. PCBs are a class of organic compounds which were widely used as coolants and insulating fluids (dielectric fluids) in the manufacture of electrical equipment such as transformers. Additionally, PCBs were used in fluorescent light fixture ballasts, locomotive electrical transformers, industrial caulks and adhesives (of particular concern in schools and commercial buildings build in the 1950s through 1970s), marine paints, stabilizing additives in flexible PVC coatings of electrical wiring, pesticide extenders, cutting oils, lubricating oils, hydraulic fluids, adhesives, wood floor finishes (such as Fabulon and other products of Halowax in the U.S.), waterproofing coatings, and in carbonless copy ("NCR") paper. Even though PCBs were completely banned from use in products in the United States as of 1979, there are still may PCB-containing materials in use and also entering the waste stream. For instance, PCB containing caulk was used in the construction and renovation of school buildings between the 1950s and late 1970s, primarily for sealing window installations and exterior building siding panels. PCB containing caulk can weather and release PCB-containing dust which can result in possible human exposure. PCBs have also been found to leach from the caulk and penetrate into the adjoining masonry. PCBs are also commonly detected in soils and waste materials impacted by waste oils generated prior to 1980, and in many pre-1980 industrial waterproofing coatings, adhesives and paints, particularly those used in military applications. Whether the concern is for PCBs in school building materials, soils, or waste materials, StoneHill can prepare and implement sampling plans to test for PCBs in accordance with U.S. EPA and State regulatory agency guidelines. In light of new findings which indicate PCBs are present in many more products than oils, in the best interests of our customers, it is StoneHill?s policy to analyze wastes for PCBs that are being prepared for off-site shipping unless the source of the contaminants in the waste material is absolutely known to not contain PCBs. Fortunately, PCB analysis is relatively inexpensive and well worth the cost considering U.S. EPA representatives have indicated that if PCBs are found in a waste material after it have been shipped off-site for disposal, the agency will take aggressive enforcement action against the responsible parties, even if there was no evidence that would suggest PCBs should have been suspected to be present in the waste materials. StoneHill is skilled at explaining the significance of finding PCBs in common-sense terms, addressing the complex PCB regulatory issues, putting the risk of exposure in perspective, and providing public relations support. These services are particularly useful due to the sensitivity of detecting PCBs in locations such as schools and other public settings.

Perfluorinated Chemicals (PFCs, PFOA, PFOS) Assessment and Sampling

PFCs are a family of man-made chemicals that have been used industrially and in consumer products since the 1950s. Some products containing PFCs include firefighting foams, non-stick coatings and cleaning products. PFCs are persistent and resist degradation in the environment. They also bioaccumulate, meaning continued exposures result in concentration increases in the blood and organs. Perfluorooctane sulfonic acid (PFOS) and perfluorooctanoic acid (PFOA) are two PFCs that have been produced in the largest amounts within the United States. Both PFOS and PFOA are classified by the EPA as emerging contaminants, chemicals or materials that are characterized by a perceived, potential or real threat to human health or the environment or by a lack of published health standards. As such, due to the toxicity, mobility and bioaccumulation potential of PFOS and PFOA, Federal, State and local agencies are focusing on identifying sources of PFCs in soil and groundwater, with particular attention on potentially impacted public and private drinking water supplies.

A common source of PFCs in the environment is firefighting foam known as aqueous film forming foam (AFFF). When PFC-containing AFFF is used for firefighting or training purposes, the PFCs in the foam can contaminate soil and sediment in nearby surface water bodies. PFCs can also readily contaminate groundwater and travel long distances with little or no degradation. The amount of PFCs that enter the groundwater depends on the type of AFFF used, where it was used, the soil condition, and other factors. If private or public wells are located nearby, they could potentially be impacted. StoneHill has extensive experience in the sampling, identification, and assessment of chemicals in the environment such as PFCs.

Vapor Intrusion Assessment and Mitigation

In recent years the intrusion of contaminated vapors into indoor air from subsurface groundwater or soil contamination has become a significant issue. Many State environmental regulatory agencies have established regulations and policies which trigger investigation of soil vapors at waste sites and adjacent properties, as well as the assessment of indoor air quality. Unfortunately, the sampling of indoor air and the interpretation of the data is challenging because so many factors contribute to indoor air quality and conditions can vary greatly over even a short period of time. StoneHill has experience with assessing and mitigating indoor air in a wide variety of settings ranging from fuel oil releases in residential settings to commercial dry cleaning facilities and industrial sites impacted by chlorinated solvents such as trichloroethylene and tetrachloroethylene. Many investigations require soil vapor and groundwater sampling to determine the potential contaminant sources and degree of subsurface contamination. If the data indicate the potential for an impact to indoor air, StoneHill will then conduct indoor air sampling. If unacceptable levels of contaminants are found in indoor air which can be attributed to the subsurface contamination, StoneHill can implement remedial actions which can include improving or modifying building ventilation, eliminating pathways for vapor migration into the building, and installing subslab depressurization systems (usually similar to radon reduction systems) to prevent the migration of soil vapor into the building. These measures can often be inexpensively implemented to reduce or eliminate vapor intrusion. Following implementation of remedial measures, StoneHill then conducts detailed performance monitoring which is critical to document that the measures were successful in eliminating or reducing the migration of contaminated vapors into the building.

Blasting Impact Assessment and Monitoring

In recent years there has been much focus on the impacts that explosives used in rock blasting have on groundwater and surface water quality. Initially, perchlorate, a product within some explosives, was identified as a concern by some State regulatory agencies. More recently, nitrate impacts from the widely used explosive ammonium-nitrate-fuel-oil (ANFO), have proven to be the more prevalent and serious issue with respect to impacts on water supply wells. At several locations in southern New Hampshire, nitrates due to ANFO use have been detected in groundwater at concentrations significantly greater than the 10 milligrams per liter (mg/l) drinking water standard, above which nitrates have been linked to ?blue baby syndrome?. Over the past several years StoneHill has gained significant experience investigating the impact to groundwater from explosives and the use of best management practices (BMPs) to reduce those impacts. The BMPs focus primarily on the use and handling of explosives on site. Additionally, in many cases it is necessary to assess the potential for impacts to nearby water supply wells. Some municipalities are now requiring groundwater monitoring wells be installed prior to commencement of blasting activities to monitor groundwater quality prior to, during and following blasting operations. Based upon StoneHill?s experience, the implementation of BMPs at blasting sites can reduce the impact of ANFO use on nitrate concentrations in groundwater and data collected by StoneHill appears to indicate that once blasting operations are completed, water quality improves in a relatively short period of time. StoneHill can assist municipalities, developers and blasting companies throughout this process including the design and implementation of groundwater monitoring programs, implementation of BMPs, interfacing with regulatory agencies, and providing public relations support, a critical component of these cases when water supply wells are threaten or impacted.

Insurance Claim Management/Cost Control

Insurance companies rely upon StoneHill to obtain the data required to assess whether insurance coverage applies to spills or other incidents involving oils or hazardous materials, and to conduct third party reviews to minimize wasteful activities and identify inappropriate costs. StoneHill also conducts site investigations and cleanups directly for insurance companies and insured parties. Our extensive hands-on experience and cost control oversight has resulted in significant cost savings for the insured and their provider. More Information...

Water Resource Impact Studies & Water Supply Services

As groundwater withdrawals from aquifers continue to increase, it is becoming more difficult to locate and permit new water supplies, and protect existing supplies. The presence of contaminants such as MTBE and lawsuits over water use rights complicate the process even further. The geologists and hydrogeologists at StoneHill can provide the expertise to locate, permit and develop new supplies, as well as prepare and implement wellhead protection plans to preserve existing water supplies. StoneHill can also develop supplies for groundwater heat pump systems. More Information...

Expert Litigation Support

StoneHill takes pride in providing straight forward and pragmatic expert litigation support for cases involving environmental contamination, geology, soils, and water resources. We believe that to minimize the cost of litigation, efforts should often be focused on utilizing available data to meet clearly defined objectives and develop conceptual models readily understood by the layperson. More Information...

Brownfields Redevelopment Services

Reclaiming under-utilized contaminated urban and industrial properties is a priority of federal, state and local governments. StoneHill's investigations, risk assessment and remediation services are a key component of a successful brownfields redevelopment project. More Information...

Licensed Site Professional Services

In Massachusetts, the Department of Environmental Protection requires that a Licensed Site Professional (LSP) directly supervise most response actions at contaminated sites in Massachusetts. StoneHill's LSP will provide project oversight utilizing the available options to minimize response action costs, liability and time to site closure. More Information...

Underground/Above Ground Tank Audits/Closure/SPCC Plans

StoneHill's experts can audit the compliance status of tank facilities and manage the testing, upgrade or removal of regulated or unregulated underground or above ground petroleum or hazardous material storage tanks. Spill Prevention (SPCC) Plans can be prepared or updated. StoneHill oversees the tank closure process with IFCI certified managers. Detailed documentation is prepared to avoid future concerns regarding a closed tank facility. More Information...

NEPA Services

StoneHill helps its wireless communications industry clients step through the NEPA compliance process, which includes assessment of impacts to endangered species and critical habitat, cultural resources, floodways, and wetlands. The NH State Historic Preservation Officer has often commended StoneHill for providing the detail required to quickly render determinations regarding potential impacts to historic properties. More Information...




600 State Street, Suite 2
Portsmouth, NH 03801
Telephone: 603-433-1935
Toll Free: 1-800-639-4503
Fax: 603-433-1942

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