Pre-construction site assessment and mitigation activities

1. Submit a Site History Report

Make sure your report includes information outlined in Health and Safety Code Article 22A.6. 

A Phase I Environmental Site Assessment compliant with ASTM E1524-21 will satisfy the site history requirement. 

Your case worker may determine no additional activities are needed if your site history indicates hazardous substances, or human and environmental health risks are unlikely at your site.

2. Submit a Subsurface Investigation Work Plan

Submit a Subsurface Investigation Work Plan that meets the requirements outlined in Health Code Article 22A.7. 

Your work plan should describe subsurface sampling for your site. Your work plan should include:

• Your plan for development
• Possible hazardous substances at your site
• Environmental concerns
• The scope of the investigation
• Data quality criteria
• Environmental risk evaluation criteria

Your sample should go at least as deep as the total depth of planned excavation, including utilities and elevator pits. Collect and analyze soil, groundwater, and soil vapor samples. You may need to analyze hazardous substances including:

• Metals
• Volatile organic compounds (VOCs)
• Total petroleum hydrocarbons (TPHs)
• Semi‐volatile organic compounds (SVOCs)
• Polychlorinated biphenyls (PCBs)
• pH
• Cyanides
• Methane and other flammable gasses
• Naturally occurring asbestos

3. Perform investigation activities

If any borings are greater than 5 feet deep, apply for a drilling permit. If your investigation is in any public right-of-way, obtain the appropriate encroachment permits.

Once we approve your work plan and you have all the necessary permits, you may perform your investigation.

4. Submit a Subsurface Investigation Report

The report should:

• Follow your work plan and any conditions stated in your approval letter
• Explain your sampling and testing methods
• Include the results of the soil, soil vapor, and/or groundwater analyses
• Compare your results to current State and Federal screening levels

5. Submit a Site Mitigation Plan (SMP) and other plans

If your Subsurface Investigation (Phase 2) Report finds hazardous substances, you will need to submit a Site Mitigation Plan (SMP). Your SMP will let us know how you will deal with the hazardous substances and should include:

• Health and safety measures including reference to a Health and Safety Plan
• Construction mitigation measures to control the generation, handling, and disposal of any excavated materials, including reference to a Site-Specific Dust Control Plan, if needed
• Short-term environmental remediation activities that falls within development scope (i.e. spot excavation)
• Long-term environmental mitigation measures to address dermal contact or vapor intrusion concerns associated with contamination left in place (e.g. soil cap, vapor intrusion mitigation system)
• Institutional controls to ensure long-term environmental mitigation measures are effective in perpetuity and that uses of the Site remain safe to public health, safety, and the environment.

We will review the SMP and reply with a letter letting you know if you need changes or if you met the requirement. You might need to submit other plans or reports.

Dust Control Plan

In San Francisco, Health Code Article 22B requires projects over half to implement site-specific dust control measures.

You must submit a Dust Control Plan if:

• Your site is ½ acre or larger
• There are sensitive receptors within 1,000 feet of your site (which is most of San Francisco)

Health and Safety Plan

If there is a risk of environmental exposures to construction workers, submit a health and safety plan.