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Here are some examples of NST's environmental investigations and remedial engineering designs that allowed permitting, continued site operation, and insurance coverage for site cleanups and waste recovery. The photo shows worker directing placement of an NST/Engineers designed, multi-stage, Catenary Grid (R) scrubber to remove acid gases from a Part B TSDF. 


 NST/Engineers has made it a practice to use only highly qualified staff on the engineering projects the Company has undertaken. This means relying on a team of experts (core staff and associates), with each individual having more than fifteen years of relevant experience.

 One kind of "relevant" experience we have used has been that of the inventors and developers of processes and equipment vital to success of a given project. Another has been the use of the trainers and developers of relevant procedures, regulations, and site work instructions that satisfy the worldwide quality requirements of ISO-9000. 

Wastewater Permitting 
The clientís factory produced fine powders used in specialty products. NST/Engineers, Inc. (NST) was asked to review the clientís wastewater stream and suggest any remedial action that might be necessary. Process wastewater and nightly maintenance crew washdown of the production equipment created a waste stream that ranged in pH from ~4 to ~12, depending on products being manufactured. The waste stream also had a high turbidity reading due to suspended solids. The wastewater treatment consisted of a settling tank that drained to the municipal sanitary sewer. The facility was in violation of their NPDES permit.

 NSTís solution was to design a treatment system that was inexpensive to implement, easy to operate and maintain, and satisfied the requirements for the permit. The system consisted of a simple pH adjustment well, retrofitted to the old system. Mixing was achieved via an air sparging ring at the bottom of the well. pH adjustment was achieved via pH controlled and metered injection of H2SO4/NaOH/MgOH. The entire system was raised eight inches from the bottom of the existing settling tank. An air operated suction pump was installed for the removal of solids from the bottom of the tank. The client was granted the necessary permit. 
Air Permitting 
This client was moving their Reinforced Fiberglass Product (RFP) Process to another state. They contacted NST for design and air permitting assistance. NST performed a review of the old plant under operating conditions and used the data gathered from a complete materials and operations review to design a workable and economical emissions system. The entire system was ergonomically designed for increased worker comfort and productivity. Using mass-balance equations, NST made recommendations for sizing and placement of filtration and exhaust equipment. NST performed the New Source Review for the new facility and completed the Air Permit applications for the state.

Subsurface Soil Remediation

 The client purchased the property, an old manufacturing facility, with the intention of using it as a trans-shipping facility. Subsequent Phase I and Phase II Environmental Site Assessments revealed that the underlying soil of the property was contaminated with Volatile Organic Compounds (VOCs). Several monitoring wells had been installed during Phase II of the Remedial Investigation (RI).

 The client contracted with NST Engineers for the Remedial Design of the project. After a complete review of the investigations of the facility, NSTís PEís and technicians designed an Air Injection and Soil Vapor Extraction system for the facility. NST used the existing monitoring wells for the extraction points, and new wells at the periphery of the underground plume for air injection points. The sub-surface piping system was routed to the equipment building. The entire project area was paved and the trans-shipping business resumed operations without further interruption. The operating heart of the system was contained in a standard size "connex" box. The air injection unit was driven by a high volume air compressor. The soil vapor extraction system included a vacuum pump, a water drop-out tank, carbon canisters for VOC adsorption, Photo Ionization Detectors (PIDs) for constant real-time monitoring, and a manifold of PID controlled valves for redirecting exhaust air that doesnít meet emission standards back into the air injection wells.

Litigation Support and Expert Witness

We provide plant and site safety inspections, health and safety plans (HASP), plant and equipment operating instructions to meet ISO 9000 and PSM requirements.

Support has been:

 analysis of materials (insulation) to determine hazardous properties (asbestos content);
 determination of remediation measures and long term costs for waste site cleanups;
 cost estimates for remediation cost - cap insurance;
 explanation of improper chemical loading leading to a highway fog fatality;
 analysis of Superfund remediation methods and effectiveness in relation to the proposed reuse of the property; and
 analysis and explanation of improper handling of asbestos leading to an asbestosis fatality.

Expert testimony and depositions have been about:
 air pollution causing illness in a valley;
 patent dispute over novelty of a power plant emissions control method, and
 insurance liability dispute over waste cleanup costs.

Chemical and Safety Engineering:
 on site inspections to determine the presence of hazards and state of OSHA compliance, and
 review of existing and preparation of new HASPs and Worker Safety Training.

Representative law firms we have supported:
Maron, Marvel & Wilks-Wilmington, DE
Curran & McGill-Philadelphia, PA
Suggs & Kelly-Columbia, SC
Willian Brinks Olds Hofer Gilson & Lione-Indianapolis, IN
Duane, Morris & Heckscher-Philadelphia, PA

Corporate Environmental Investigations

 The client, an environmental investigation firm, was reviewing remediation procedures implemented by a large corporation for several of their Superfund clean-up sites. The client contacted NST Engineers to perform the environmental reviews and report recommendations. The purpose of these reviews was to recommend "Cost Cap" insurance limits for the individual cleanup projects. The limits were based on such variables as the physical size of the project; the type and quantities of the contaminants to be removed, the degree of remediation required, the technology being employed, and the professional reputations of the contractors involved.

 The resulting NST Engineers reports were a basis for insurance policies from underwriters to the corporation. The multi-year cleanup, with portions expected to last nearly a decade, is ongoing. Over that period, the corporation is protected from potentially large overruns in remediation costs.

Health and Safety Plans (HASP)

 Several clients have contacted NST to supply Health and Safety Plans, often as part of a large scale remediation project we engineered.

 Recently, a company noticed that its Workmanís Compensation Insurance premiums were over budget. Although not required by OSHA to maintain a complete Health And Safety Plan by virtue of the number of employees, they contacted us to write a comprehensive, facility specific HASP. The result was that the clientís insurance premiums were significantly reduced, more than offsetting the cost of our services.

Soil Remediation at Massachusetts Public Housing Project

  Our New England Engineer is the Licensed Site Professional (LSP) of record for Roxse Homes. This is a subsidized housing renovation project for the Massachusetts Housing Finance Agency as Interim Asset Manager for HUD. The properties comprise three noncontiguous parcels, approximately one city block each, in the Roxbury section of Boston. In August, 1998, during the first phase of renovation construction, excavated soils were characterized for disposal and found to exceed MCP S-1 concentrations for lead and several PAHs. Twenty borings were installed across all three parcels and concentrations of lead and certain Poly Aromatic Hydrocarbons (PAHs) exceeding Reportable Concentrations RCS-1 and RCS-2 were detected. In some samples, PAHs exceeded S-1, S-2 and S-3 concentrations.

 Our LSP prepared the current Release Abatement Measure (RAM) plans for foundation and utility work, and will be preparing sitewide RAM plans for removal and replacement of 2-3 feet of accessible soils from the sites. He is supervising the performance of the Method 3 risk characterization required due to the presence of PAHs in soils exceeding S-3 standards. He will be preparing the Phase III Comprehensive Evaluation of Remedial Action Alternatives. He will also be preparing the necessary Activity and Use Limitations required to support the Response Action Outcome opinion he must render at completion of the remediation. This project was completed in 2000.

Underground Storage Tanks

  A client owns a large regional transit company. In the process of upgrading their fuel storage system, a sizable amount of petroleum-hydrocarbon, contaminated soil was encountered. NST Engineers was contacted to develop a remedial action work plan for the site.

 A difficulty encountered was that the amount of lost fuel was unknown. Further, the site was located on sandy soil over an un-contained aquifer with a high-volume, privately- owned, well in the vicinity. Our plan, including a detailed hydrologic study, was implemented.

  With the installation of upgraded tanks, and a state-of-the-art delivery, spill prevention, and leak detection system, The site is now back in productive operation. The environmental regulators have agreed that the remedial action was sufficient and that there will be no impact on groundwater.

Sub-Surface Soil Venting

  As part of a Brownfields redevelopment project a town was redeveloping a derelict manufacturing plant into a museum. During the renovation, odors were detected coming from beneath the slab floor. It was determined that the odors were emanating from spilled or leaking #2 fuel oil when the plant was in operation. Further investigation showed that the concentrations in air were small enough that environmental regulators would accept soil odor extraction and capping as a remedy.

 NST designed and installed a removal system for the offending odors. The system has suction and fresh-air-intake piping layered in stone beneath the slab floor. The system is powered by a regenerative blower assembly. The system was designed for odors to be vented through an existing chimney with no change to the exterior historical features of the site.

Control of Hazardous Plant Air Exhaust

 NST designed and installed two large toxic exhaust wet scrubbing systems using the latest in gas-liquid contacting technology, the Catenary Grid (R). The clientís plants had been barred from operation until advanced and effective cleanup techniques could be installed and proven. The plants had been troubled by toxic inorganic vapors, organic vapors, and RCRA listed metalsí dust. The wet scrubbing installations were approved at eastern and western U. S. sites; one urban and one rural. Due to the requirements for uninterrupted plant operation, NST designed and installed a completely redundant PLC control system at the urban location.

 In addition to wet scrubbing system design, specification, construction, and installation, NST provided liaison with environmental agencies that allowed certification of otherwise trouble-ridden processes and plant operations.


Determination of the Mechanisms Causing the Inadvertent Formation of Pollutants in the Environment.

 These were studies of: chlorination water treatments and their conversion of hydrocarbons to halogenated hydrocarbons; the potential for chlorination via seawater chlorine; the interconversion of one halogenated species to another (such as DDT to PCBs); breakdown of dyes, dispersants, coatings and related materials in the environment to produce toxic products.

Assessment of the Importance of Water Quality Factors in Coal Mining, Electric Power Production, and Petroleum Refining

 This was a study of acid mine drainage, spoil leachates, ash leachates, toxins to biota, toxic sediments, and problems of thermal pollution and cooling; all summarized into the needs for baseline studies prior to construction or other land use modifications.

 Determination of the Needs for Areawide Wastewater Treatment Plans and Facilities in the Northeast U.S.

 This was a study of the interrelationships between water protection (removal of solids), land use (sludge disposal), and clean air maintenance (incineration practices); permissable volume and quality of effluents safely dischargeable to marine and fresh surface waters; groundwater levels, recharging, salt water intrusion; and proportionate sharing of costs between domestic and industrial users.

Values Recovery from Solid Wastes and Extractive Processes

 We recommended recovery processes for alumina from dross in secondary aluminum refining. Markets and customers were identified for about ten different alumina products, of varying purities, ranging from abrasives through pharmaceuticals and chemicals to refractories.

 A process design was prepared for the hydrometallurgical extraction of nickel and cobalt. It included operating and capital cost analysis. The design was for a two million pounds per year plant producing high purity metals from sulfide ore flotation cell concentrates, using ammonia dissolution and hydrogen reduction.

 We specified processes for nickel catalyst recovery from the hydrogenation of oils, and for ferrous values recovery from titanium dioxide production.

 Processes were designed for the use of power plant coal ash in producing commercially valuable fibrous materials for thermal and sound insulation; and for use in composite plastics for structural strength.

 We evaluated client participation in a demonstration solid waste and sewage sludge processing and resource recovery facility, including the development and marketing of recovered products. Resource recovery included: ferrous and nonferrous metals, glass, low sulfur fuel, and soil conditioners. We recommended hazardous materials safeguards for employees and for environmental protection.


 Our staff associates provide complementary specialization. Advance Environmental Redevelopment, LLC, provides a Professional Geologistís insight into Superfund site investigation, feasibility studies, and remediation work.

 As an example of our use of specialized experts in project execution, our team included the inventor of the Catenary Grid ô wet scrubbing system on two critical projects. They were scrubbing systems design and installation for the plant exhaust air of two Treatment Storage and Disposal (TSD) facilities. The plants were recovering values and detoxifying cyanide electroplating wastes and other metal-containing acidic and caustic liquids and sludges. Our wet scrubbing systems have been successfully removing hazardous acid gases and metal salt dusts from the exhaust air, under redundant automatic control, for about ten years.

 Our affiliation with Kroll Worldwide makes the NST-Kroll association the most powerful environmental investigative organization in the Delaware, northern Maryland, southeastern Pennsylvania, and southern New Jersey region. Kroll is known nationwide for its ability to greatly expand the number of known potentially responsible parties (PRPs) for a given hazardous or other troublesome site.

  They have a twenty-five year background in international civil and criminal investigative work, combined with security services and forensic accounting. We provide Kroll with chemical and environmental engineering services.

For a fee-based consultation call with a Licensed Professional Engineer between 3:00pm and 5:00pm Eastern Daylight Time, call (302) 239-2700.

For information at any time on our Hazardous Waste Operations and Emergency Response (HAZWOPER) and other safety training, click here.