Soil: Your Most Expensive Development Mistake

When real estate property developers are prepared to start a ground-up or redevelopment construction project, they shouldn’t undervalue the importance of soil testing. Likely, they’ll need to build mass soil transport or excavation into their project plan. Why? 

Soil testing is vital for testing the bearing capacity so your team can properly consider the building foundation, but there are other important reasons to test too. Soil testing is required prior to excavation in order to determine the physical and chemical composition of the dirt. Soil characterization can change layer to layer, from the weather, previous site management, and more. That’s why before contractors are allowed to disturb the soil, it must be tested at an accredited analytical laboratory. 

Why Do I Have to Test Soil? 


The most important reason is for the Safety of on-site construction and development workers, and the as well as the surrounding public is the primary reason developers are required by law to complete a soil characterization. 

While some chemicals can be detected through visual observation or smell, many chemicals cannot be detected unless they are analyzed in a lab. Certain petroleum hydrocarbons, solvents, metals, and pesticides are carcinogenic (cancer-causing) and may produce acute and/or chronic effects on human health. 

During soil disturbing activities When disturbing the soil through excavation or transportation on a job site, these chemicals may be kicked up as dust and inhaled by on-the-ground personnel over the duration of an entire workday. If a strong wind is present, the dust may drift off-site and potentially expose sensitive receptors such as hospitals, schools, or daycare facilities. Regulatory agencies often require dust mitigation measures, dust monitoring, and personal protection equipment at construction sites to protect the health of all individuals involved. 

Negligence and failure to mitigate these dangers can lead to litigation and damage companies’ reputations. When soil testing is done haphazardly or not at all, you put your team and your brand value at risk. 


Soil also needs to be tested to determine where it can be transported. Another reason to test soil is to determine where the soil can be transported. If the soil is to be disposed of as waste, there are limitations as to which landfill may accept it. In order to determine which classification applies to the soil, extensive laboratory testing is required. 

  • Soil that is designated as Class II contains concentrations of contaminants that are below hazardous levels. Class III soil is considered non-hazardous municipal solid waste and may be transported and reused at another job location, which may offset some costs. 
  • Soil that is hazardous per California Code of Regulations (CCR) Title 22, but does not exceed federal regulations is considered Class I hazardous waste and may be accepted at only two locations in the state of California. 
  • Chemical concentrations that exceed federal regulations under the Resource Conservation and Recovery Act (RCRA) are considered the most hazardous and may be subject to additional treatment methodologies (i.e., incineration) and are limited to acceptance at select facilities in the United States. 

If soil testing is done incorrectly, developers could end up spending too much money on transportation, or waste time coordinating complicated logistics that might not have been necessary in the first place. It’s important to find a trusted partner to complete your soil testing in order to mitigate the financial risk soil can take on your project.

Soil Due Diligence Checklist

Soil Testing Process

The number of representative soil samples to be analyzed depends on the volume of soil that is being removed. A commonly referenced sampling schedule can be found in Information Advisory: Clean Imported Fill Material published by the Department of Toxic Substances Control (DTSC) in 2001; however, it is common that a landfill may request additional samples.

The soil samples are then transported to a state-certified laboratory and analyzed for a minimum of:

  1. total petroleum hydrocarbons (TPH)
  2. volatile organic compounds (VOC)
  3. semi-volatile organic compounds (SVOC)
  4. polycyclic aromatic hydrocarbons/polynuclear aromatic hydrocarbons (PAH/PNA)
  5. polychlorinated biphenyls (PCB)
  6. organochlorine (OC) pesticides
  7. Metals
  8. asbestos

At their discretion, landfills may also request additional analyte and waste extraction tests, which help determine if the waste is hazardous.

Soil Testing Mistakes

Common mistakes that occur during soil characterization include:

  • an insufficient number of samples
  • samples collected at incorrect depths and/or locations
  • missing analyte parameters. 

The consequences of these mistakes vary but are almost guaranteed to affect your project timeline and budget in one manner or another. In a best-case scenario, a mistake such as a missing analyte parameter will require a call to the analytical laboratory to request additional testing be performed. In a worst-case scenario, additional sampling must be performed, which would require remobilization of field personnel and additional lab costs. 

In addition, misinterpreting the soil classification may also prove to be a costly mistake as well. For example, classifying a soil as Class I is on average hundreds of dollars per cubic yard more expensive than if it were classified as a Class II soil. 

Prioritize Soil Disposal to Save Costs

Soil disposal is a critical component of almost every development project and is frequently under-budgeted in cost estimates. Unfortunately, under-budgeting your soil process could actually send you over budget in the long run. The revelation of hazardous soil material can add hundreds of thousands of dollars in expenses and severely jeopardize a project’s finances. Performing soil characterization in the early stages of development is key to avoiding costly mistakes and delays in a busy timeline.

Ready to get testing? Contact Essel at 1-800-595-7616, or request a meeting with one of our consultants to see how Essel can partner with you for your soil testing needs, or download our comprehensive Soil Due Diligence Checklist for landowners and developers.