How common is it to redevelop industrial properties such as this one?
The City of San Francisco, along with many other cities in California, is embracing redevelopment of industrial properties because it allows for the preservation of green space and creatively addresses the need for more housing and commercial space. Also, the Eastern Neighborhoods Plan provides more guidance about redevelopment happening in this part of San Francisco and can be found here. Related California is very experienced in transforming industrial land into residential or commercial mixed-use properties and will implement industry best practices here at 1601 Mariposa.
What kinds of substances – hazardous or otherwise, are involved?
There are several issues Related California will be addressing in its Response Plan. The first is the underground storage tanks. Related commissioned several site investigations which identified additional contamination as a result of the underground storage tanks including traces of arsenic, lead, and nickel in the soil, soil gas, slight groundwater contamination and the presence of serpentine rock as a result of construction gravel infill. While they do not pose an immediate health hazard, they will all be remediated to make the site safe and compliant with California Department of Toxic Substances Control’s (DTSC) standards.
What is the plan for clean-up?
Related California has commissioned several site investigations over the course of two years to further investigate soil, soil gas, and groundwater contamination under DTSC’s Voluntary Clean-up Program. Based on those findings, Related California and DTSC are in the midst of finalizing a clean-up agreement. Once the Response Plan, which defines the clean-up goal and process for the site, is approved by DTSC then Related will be able to move ahead with remediation and make the site safe, as stipulated by the State of California’s standards, for conversion into housing, parks, and stores. This is a public process and will be open for comment.
How much time will the clean-up take?
While removal of the tanks will take less than one week, some of the other activities may take longer, such as grading the site.
What agencies are you working with?
This process will be managed and monitored by both local and state agencies. The California Department of Toxic Substances Control (DTSC) will be primary agency ultimately releasing the final Response Plan. The Response Plan will also be included in the San Francisco Planning Department’s focused EIR. Planning will also coordinate with the San Francisco Department of Public Health (DPH) and the Bay Area Air Quality Management District (BAAQMD) on the implementation of the Response Plan.
How long will it take to remove the underground storage tanks? Is it dangerous?
The underground tanks, which are the main source of site’s contamination, will be removed under a highly supervised process that will include public notification, dust control and on-site monitoring during removal and abatement procedures. This is swift process generally taking up to one or two days.
The tanks do not pose an immediate threat to neighbors. All three tanks were capped and sealed back in 1986 and the San Francisco Department of Public Health (DPH) Environmental Health Section issued a Remedial Action Completion Certificate on October 21, 1998. Under the State of California’s standards however, removal is required because the land is being converted from an industrial use into housing, parks and stores.
How is the construction dust from the project monitored?
Demolition activities, construction traffic, site preparation and foundation work, and material stockpiles all have potential to generate dust during the demolition, remediation, and construction phases of the project. Related will be submitting a Dust Control Plan for demolition activities to the City for approval in accordance with the requirements established in Bay Area Air Quality Management District (BAAQMD) regulations and in coordination with the San Francisco Department of Public Health (SFDPH).
Best Management Practices (BMPs) including wetting and seeding unpaved or inactive areas, minimizing activity during periods of high wind, sweeping paved areas, covering trucks will be implemented. These dust control measures are intended to achieve a goal of no visible dust emissions associated with soil disturbance or excavation, to the extent required by BAAQMD and SFDPH. To ensure effectiveness of the control activities, dust monitors are set up in downwind areas. Real time dust monitoring will be conducted to ensure dust concentrations do not exceed nuisance levels, determined by BAAQMD, at the site boundaries.
We will coordinate with our immediate neighbors to ensure construction-related impacts are minimized as much as possible.