Environmental scientists and geology (Part 1): The first phase of an environmental geology investigation
Deborah Painter (USA)
I am an ecologist and general environmental scientist living in the USA and specialising in transportation, energy and industrial development planning to minimise deleterious environmental impacts. I have also written several articles for this magazine. As such, I appreciate just how much local geology is a vital consideration in many circumstances and especially during one of my routine responsibilities – undertaking a Phase I Hazardous Materials Site Assessment of an industrial or commercial property in the United States.
This is the first of three articles on how I and other environmental scientists apply our knowledge of geology in our day to day work.
But what is the purpose of these assessments? Companies such as my employer do these to benefit a person or business desiring a loan from a bank to purchase a property or to pay for upgrades. Cities and counties also contract with environmental companies for Phase I Environmental Site Assessments for properties they own and want to improve, or intend to acquire for resale to private parties.
For example, city officials may have their eyes on an old former school and grounds as the future site for a new police station, and want to know how expensive it would be to renovate it as opposed to demolishing it to build a new structure. The assessment is done to satisfy the current American Society of Testing and Materials (ASTM) Standard E 1527-13: Standard Practice for Environmental Site Assessments (2013), and the United States Environmental Protection Agency’s Standards and Practices for All Appropriate Inquiries – 40 CFR Part 312.
The assessment addresses the “innocent landowner defense” provision of the United States Comprehensive Environmental Response, Compensation and Liability Act (CERCLA) of 1980. The above laws focus on an old problem. The presence of impacted soil, soil vapour or groundwater at a property can reduce its value if contamination means liability for the person or business entity (Fig. 1). The bank can then decide to proceed or not proceed and it or the client might ask for tests in the second phase.
The person who conducts a Phase I Environmental Site Assessment is a trained environmental scientist, such as me. The scientist need not be a geologist, but it was essential that I completed geology coursework and recognise how chemicals and processes utilised by various industries might enter and affect groundwater and storm water. ‘Environmental Professionals’, possessing an environmental engineering license must oversee and provide quality control for a report. It is the Environmental Professional who co-signs the report.
In many ways, when I do a Phase I Environmental Site Assessment, I am like a detective who wants to determine what happened on the subject property decades ago up to the present day. I often feel like the “gumshoes” of old detective novels.
If I can secure a copy of the property plan before I do my site walk, it will help me immensely. I also do a desktop review of the soil type, groundwater depth and geological setting. There are companies that research regulatory records, nearby water wells and even radon potential for the investigator for a fee that is included in the bid we send to the customer. The reports these companies create save many hours of searching and visits to county departments and can save the customer money and time.
Local fire departments and health departments have records that date back several years. I visit or write letters to them to request records. Once I obtain the historical aerial photographs, old street directories, old topographic maps, title information and building permits issued, I examine them closely. Sanborn Fire Insurance Maps help me a great deal too. These were published from the 1800s until the 1950s by the Sanborn Map Company to help insurance companies determine if a property nearby could pose a fire risk to the property being insured. These hand drawn maps were only published for urban areas and small towns. A Sanborn Map can show if a petrol retailer, iron works or dry cleaning establishment was present on or near the subject property so long ago that it is now forgotten by the community.
Why is it important to know if a dry-cleaning establishment or a petrol service station was present on a property decades ago? A cleaning solution used in recent decades is tetrachloroethylene. It has been noted as a carcinogen in laboratory animals. If it enters the soil it breaks down to form vinyl chloride, which can cause liver damage and damage to the central nervous system in humans.
If a petrol service station was present and is now long gone, it may have changed ownership before the enactment of the CERCLA laws, and there could be forgotten leaking underground petrol tanks on the premises.
Regulatory research is next. State and Federal databases have information on whether the subject property and other sites within a radius of up to 1.6km have registered above ground and below ground petrol tanks and chemical tanks. I look for any releases or incidents on record. Most subject properties do not have naturally occurring hazardous materials. Radon is an exception. It is a lung cancer causing gas and is a concern for structures built in areas with bedrock and soil that contain uranium. The rock could be metamorphic, igneous or sedimentary. Therefore, the potential for radon in the general area is examined.
The subject property we will focus on in this discussion is a manufacturer of plastic garden supplies and toys in a rural area in northern Kentucky in the USA, within the floodplain of the Ohio River. We’ll use it throughout the article as a typical site I have seen (Figs. 2, 3 and 4). The general area’s radon potential is 2, which is a moderate risk.
The facility was built atop Glacial Outwash of Wisconsinian age, a continuation of the Glacial Outwash in south-eastern Ohio, just across the river. A bit further upgradient of our locale is Eolian (wind-transported) sediment, a dune sand of Quaternary age. The foothills of the Appalachian Mountains to the south are Ohio Shale, from the Middle and Upper Devonian. The higher slopes are Farmers Member, Borden Formation (Mississippian) and Nancy Member, Borden Formation, also Mississippian (Fig. 5).
Gradient is also important. If the database search reveals that a facility near our site has had chemical releases to surface waters in the past decade, it is not relevant if the business is down gradient from the subject property. The release is listed and duly noted; however, up gradient sites receive the most attention.
The next step is scheduling a site walk with persons who manage the subject property. A site walk includes interviews with these persons and obtaining copies of recent ‘manifests’, which are invoices setting out when process water from the industrial activities is routinely picked up by outside contractors for proper disposal. Almost all industries use water for keeping their equipment cool. Companies create manifests when waste oil is collected in drums and other containers, and removed in similar manner. If the manifests are complete, I can determine if routine steps are being taken to keep such substances from accumulating and potentially causing problems.
The following pictures are photographs of various facilities for which I have carried out site walks across the United States. I selected them based on how well they illustrate the environmental conditions I seek. For example, Fig. 6 depicts a floor drain that is draining well and located in an area where the floor is kept clean. I knew where the wash water is being collected.
Fig. 7 is a ‘bad’ example of a floor drain. It is corroded and the floor is stained. The destination of the wash water is a sump visible in the photo that is not well maintained. Fig. 8 is a ‘good’ example of process water and other waste materials properly packaged and ready to be picked up for disposal. Fig. 9 is another ‘bad’ example, this time of process water left in a large plastic drum in a corner, with boxes and large plastic pieces blocking access.
Fig. 10 is a ‘good’ example of batteries that are placed on a pallet so that if there are any leaks they can be detected and the materials absorbed with multipurpose absorbent for disposal. Fig. 11 is a ‘bad’ example of a facility, in this case, an automobile repair shop, which allowed transmissions and engines to leak transmission fluid and other hydrocarbons onto a bare concrete floor. Fig. 12 is a photo of an oil absorbent spill kit of the kind that the automobile repair shop needed to keep on hand but did not.
A site walk also includes a thorough examination of any buildings, the manufacturing processes, chemicals and heavy metals used, and an examination of the exterior and any vacant vegetated areas and storage areas. I look for leaking pole and ground electric transformers because models installed before the 1990s may contain polychlorinated biphenyls as an internal lubricant. I also keep my eyes open for pipes protruding from the ground that might be vent pipes or fill ports for underground storage tanks (Fig. 13). I count the fire extinguishers and determine if they are in good working order and whether they are present throughout the facility.
It is important that employees know what substances are present and the potential harm of these substances, and they are trained in what to do if a substance is accidentally released. A large binder book of “Material Safety Data Sheets” must be kept on the premises and be readily available to everyone. Every chemical used, even common hand cleaners, should be in this binder. I make note of the potential presence of asbestos containing materials or lead based paint, but do not collect samples. Sampling may take place later if it appears that these may be present.
I take many photographs, which I share with the Environmental Professional, and he or she will work with me to decide which to include in the final report. If I see something that needs correction, I point the issue out to the management. Once the site walk is done and I have said my goodbyes to managers, I photograph the exteriors of nearby properties and take notes during my ‘drive-by’ assessment (Figs. 14 and 15). This helps me see any environmental problems at nearby upgradient properties that the database search might have missed. Not all properties near the subject property are listed in database searches. If I recommend to the Environmental Professional who reviews my report that there were environmental problems, either current or historic that could constitute a liability, and that a Phase II Environmental Site Assessment is in order, he or she will either concur or ask for me to conclude otherwise and state why.
Many clients will pay for a Phase II Environmental Site Assessment, in which a subsurface investigation tests soil, soil gas and/or groundwater to identify the sources and precise locations of environmental problems. Metal detectors find underground storage tanks. Photo ionisation detectors find hydrocarbons released into the soil from leaking tanks. The geologists drill for soil and groundwater samples that go to a laboratory for analysis.
Such an assessment must be conducted by a professional geologist with a Professional Geologist certification. Should a Phase II reveal significant environmental problems, a Phase III Environmental Site Assessment is recommended. This consists of removal of the tanks, the radon gas or other problems, and impacted soil and groundwater excavation and removal to an approved facility. The soil is replaced with clean soil. Monitoring wells are installed for a multi-year monitoring schedule to assure that there is no migration offsite, and to assure that the remediation was complete.
I estimate that 80% of the geologists whom I know personally spend their entire careers in environmental geology because of the ready availability of this work. Most obtain jobs immediately upon receiving their degrees.
|The other parts in this series comprise:|
|Environmental scientists and geology (Part 1): The first phase of an environmental geology investigation|
|Environmental scientists and geology (Part 2): Geology and soil science in the ‘Wetlands and Waters Permitting’ process in the USA|
|Environmental scientists and geology (Part 3): Geology and soil science in the ‘National Environmental Policy Act document’ process in the USA|
Above Ground Storage Tank Capacity Chart: https://www.hmttank.com/Resources/Tank-Capacity-Chart
American Society of Testing and Materials (ASTM), 2013, Standard E-1527-13: Standard Practice for Environmental Site Assessments. ASTM International: https://www.astm.org/Standards/E1527.htm
Environmental Data Resources Summary Radius Map Report for Site Name, June 12, 2014.
National Institutes of Health National Library of Medicine Vinyl Chloride Compound Summary: Vinyl chloride | H2C=CHCl – PubChem (nih.gov)
University of Kentucky Geologic Survey Kentucky Geologic Map Service: https://kgs.uky.edu/kygeode/geomap/
U.S. Department of Agriculture, Natural Resource Conservation Service Web Soil Survey, 2021: https://websoilsurvey.sc.egov.usda.gov/App/HomePage.htm
U.S. Environmental Protection Agency’s Standards and Practices for All Appropriate Inquiries – 40 CFR Part 312.
U. S. Environmental Protection Agency EnviroFactsMapper: https://enviro.epa.gov/
Virginia Department of Health Tetrachloroethylene Fact Sheet: Tetrachloroethylene (PCE) – Environmental Health (virginia.gov)