The Frankford Friends School (FFS) planned outdoor classroom on the site of the Central Methodist Church building is moving ahead as planned we learned at a public meeting held on May 5th. The purpose of the meeting was to inform the public about the results of the soil study of the site at 1515 Orthodox Street which was done by Duffield Associates.
When the church was demolished, a layer of fill was brought in to level off the lot. The top 12 inches of the soil was tested and found to contain benzo(a)pyrene and dibenzo(a,h)anthracene. These are contaminants often found in fill in the city. They can be found in engine oil, ash, exhaust, burned charcoal, etc. In high enough concentrations they can do unpleasant things to the human body. Additional risk information at these links: benzo(a)pyrene and dibenzo(a,h)anthracene
The levels found exceed what is permitted under the Statewide Health Standards for residential use but not for non residential use. However schools are considered residential properties in Pennsylvania for this purpose and must comply with the residential standards.
Because the site will not be continuously occupied like a residence, Duffield did a site specific risk assessment to see what the exposures might be for the way this lot will actually be used.
They assumed exposure for 220 days per year for 8 hours each day which is far above what the actual use will be. Using the EPA risk modeling program and assuming the maximum concentrations of the contaminants from the samples taken, they found that under those assumptions there is no unacceptable cancer risk.
Duffield recommended that the school incorporate the EPA’s best management practices for urban gardens:
- Top dress the garden area with clean material.
- Mulch walkways and other areas to reduce dusk.
- Build raised beds for growing food crops.
- Do not use certain type of treated lumber for raised beds.
- Consider growing ornamental plants instead of food crops.
FFS intends to follow these recommendations.
With luck there should be a grand opening sometime this October.
