Shell Engineering and Associates is an environmental engineering company formed in 1975.  Located in Columbia, Missouri USA Shell Engineering is home to experts in air quality site assessment, dispersion modeling, and ambient air monitoring among other fields of environmental engineering.  Our first modeling jobs in the mid 1970’s involved dispersion air modeling to determine the impact of utility and industrial sites to determine the effect of proposed environmental regulations being considered at that time.  Ambient air monitoring for one of our first clients was established in 1978 to fulfill the requirements of the newly written Federal Prevention of Significant Deterioration regulations.  Since the 1970s,  numerous similar environmental studies have been undertaken to insure that industry is able to operate in environmentally accepted manners.

Shell Engineering and Associates, Inc. is a Family-Owned Business, and classified as a Veteran-Owned Small Business. Strategic planning, permitting and dispersion modeling are performed by engineers.  Our present staff covers the field of mechanical, chemical, electrical, civil, industrial and environmental engineering, electronics, chemistry, occupational safety, biology, meteorology, computer science, education and business.

Shell Engineering provides services and training for environmental management, environmental monitoring and engineering. Shell Engineering has completed hundreds of projects since 1975 throughout the United States, Canada, Central America, South America, Asia and Africa.

Importance of a Comprehensive Air Quality Assessment

Shell Engineering & Associates, Inc., is an established environmental management consulting company specializing in air quality testing and air quality monitoring.  For over four decades Shell Engineering and Associates, Inc. has assisted industrial, institutional, and municipal facilities with the performance of their operations using accepted environmental practices.  Our success with air quality assessments comes from our ability to communicate with our clients, our ability to overcome obstacles by exploring alternatives and the use of proven scientific methods, and our ability to put together common sense strategies.

Air Quality Testing

Our background and experience air quality testing allows us to provide a comprehensive approach to each facility.  This includes the review of historical and present operations concerning air related emissions, providing strategies and permits for future operations, review and collection of data for ongoing air quality compliance and trend analysis, dispersion air modeling to predict the air quality impact of facilities in neighboring areas, ambient air monitoring to actually measure the impact of pollutants downwind of the facility, and audits to provide an accurate air quality assessment of how well the facility is operating within their permit limitations and regulations at a specific point in time.  Our clients benefit from our comprehensive approach and understanding of air quality regulations, and our ability to provide the data and tools (air monitoring, air modeling, emission calculations) necessary to make informed timely decisions

Shell Engineering and Associates, Inc., specializes in ambient air quality monitoring services. As opposed to dispersion modeling’s reliance on mathematical predictions, ambient air monitoring actually measures for level of air quality at a specific location over a given time period. The results of ambient air quality monitoring can be used to establish actual pollutant levels, confirm predictions from dispersion models, and provide air quality trends over a long time period. Monitoring data can also be used to refine dispersion modeling outputs and, establish air quality maintenance areas.
Monitoring facilities have been established and operated in New York, Hawaii, Canada, South America, the Middle East and Africa. Independent analysis and auditing of ambient air quality are just a few of the capabilities of our company.
THE FOLLOWING ARE TYPICAL AIR QUALITY MONITORING SERVICES:
Criteria pollutants: TSP H2S SO2 NO2 CO PM-10 Ozone Lead
Meteorological Data – Typical parameters include: temperature, humidity, rainfall, radiation, evaporation, wind speed, wind direction and Sigma Theta
Non-criteria air toxics, metals and volatile organics (TO – 1 through TO -14 methods, NIOSH/OSHA methods)

AIR QUALITY MONITORING PROGRAMS

Because reliable data is the foundation of a successful air quality monitoring program, the strictest ambient air quality standards are applied to the operating methods. The ambient air quality assurance audits are based on the National Institute for Standards & Technology for traceable gases. The firm has developed and rigidly followed procedural and maintenance manuals for monitoring that meet all of EPA’s current guidelines. Our staff and technicians have a thorough knowledge of ambient air monitoring equipment.
Customer service to Shell Engineering means meeting the customer’s needs successfully and in a timely manner. Assistance and training are offered to those who wish to purchase the ambient air monitoring equipment. We will offer training for those who wish to maintain it, audit it for air quality assurance and provide data for themselves. In other operations, complete turnkey sites are established. The client is then provided reliable and acceptable data for their ongoing compliance needs. Of course, ambient air monitoring consists of more than just working with numbers and ambient air quality equipment. Shell Engineering’s complete environmental air quality background ensures that the results of the ambient air quality monitoring studies, combined with the dispersion modeling and permitting reports fully meet the regulatory and permitting needs of our clients.
A client with special needs in dealing with governmental agencies will benefit from Shell Engineering’s good working relationship with governmental agencies and its knowledge of what these agencies require. The firm can advise the client on PSD permitting and provide experienced expert witnesses for various legal cases.

DISPERSION AIR MODELING

Dispersion air modeling provides an important tool for air quality assessments.  Air dispersion modeling provides a prediction of the air quality impact from pollutants emitted from facility operations.  The impact can vary based on stack parameters (location, height, exit temperature and exit gas velocity).  Other factors that affect the modeled impact include the facility configuration, the ground level height compared to the stack height, and the local meteorological conditions. Air dispersion modeling takes all of this into account to allow the user to predict what impact one can expect adjacent to an industrial facility.  In addition, what-if scenarios can also be modeled.  For example, what happens if we move the stack x-meters from its proposed height?  What happens if one increases production (resulting in an increase level of air-emissions)? Or how does the impact from a neighboring plant combine with your facility affect the general public. The versatility of air dispersion modeling allows industrial facilities to optimize their operations and to minimize their impact off-plant property.

INDUSTRIES USING AIR DISPERSION MODELING

Air quality control agencies usually require that industries simulate the impact of an expansion within their plants by the use of dispersion models. Applications for major permits must contain the modeling results. Shell Engineering and Associates, Inc., has been conducting dispersion modeling studies since 1975 and provided modeling training to overseas students.   Clients include almost every type of industrial plant: power plants, steel plants, charcoal plants, automobile plants, manufacturing industries, incinerators, refractories and iron ore palletizing plants.

WHY CHOOSE SHELL ENGINEERING FOR AIR DISPERSION MODELING

The staff of Shell Engineering uses EPA guideline models, and is especially adept at developing complete permitting packages. Dispersion modeling, coupled with expertise in monitoring and dealing with governmental agencies, will provide you with the information you need for virtually any case or permitting action in which you are involved.

The permitting and dispersion modeling services typically include:

• Determining the impact of existing and new sources and assistance in obtaining necessary permits.
• Use of the EPA GEP guidelines to determine the best location and height for a new stack.
• Determining possible methods of control and their effect on the potential impact.
• Determining the impact due to fuel switching (coal/gas/fuel oil).
• Determining the impact of changing stack height, flow rates or temperature.
• Determining the impact of new standards such as a one hour SO2 standard.
• Statistically correlating monitoring data to modeling data and determining trend analysis (actual data to predicted data).
• Use of dispersion modeling to select monitoring site locations through the execution of EPA guideline models.
• Determining possible site locations for new facilities

Sulfur Dioxide (SO2 )

In 2010, the US EPA finalized a new 1-hour National Ambient Air Quality Standard (NAAQS) for SO2. Since that time, a number of guidance documents have been issued by the US EPA to clarify the modeling procedures needed to demonstrate compliance. The tighter SO2 NAAQS standards have resulted in more refined analyses of interactions between sources (culpability analysis) as well as a tiered approach regarding background monitor values. For example, in some cases hourly/seasonal background data is appropriate rather than a single background value. In other cases, the background monitor data may be modified with agreement from the permitting agency to avoid “double counting” nearby sources. These are challenges that must be navigated on a case-by-case basis. To learn more about the EPA’s NAAQS standards click here. Please contact Shell Engineering if we can assist you with developing a compliance plan for SO2.

Particulate Matter

In 2013, the US EPA provided new guidance for PM2.5 (particulate matter < 2.5 microns) permit modeling. This guidance encompasses a number of recent changes, and in particular addresses considerations of the secondarily formed component of PM2.5. A facility that emits significant quantities of PM2.5 precursors such as SO2 and NOx, must account for the PM2.5 formed through chemical reactions with the atmosphere as a result of these emissions. The methods for determining an appropriate value for the secondary impact vary and may include both qualitative and quantitative portions, because modeling tools for the chemical transformation are not readily available. Shell Engineering has experience with demonstration of compliance for the current PM2.5 NAAQS, including the analysis of secondary impacts. To learn more about the EPA NAAQS standards click here. Please contact Shell Engineering if we can assist you with developing a compliance plan for PM2.5
Nitrogen Dioxide (NO2)
In 2010, the US EPA also finalized a new 1-hour NAAQS for NO2. There are many similarities between the procedures for 1-hour modeling of NO2 and SO2. However, the complexity of chemical conversions between NO and NO2 in the atmosphere may not be realistically accounted for in the traditional dispersion model. In cases where further refinement is needed, the use of non-linear model options that require additional data, including ozone conditions and stack NO2/NOx ratios, may be justified. Although simple Tier 1 approaches are preferred whenever possible, Shell Engineering has experience implementing more complex refinements when necessary. Please contact Shell Engineering if we can assist you with developing a compliance plan for NO2. To learn more about the EPA NAAQS standards click here. Please contact Shell Engineering if we can assist you with developing a compliance plan for NO2