STAUFFER CHEMICAL COMPANY
TARPON SPRINGS, FLORIDA
The U.S. Environmental Protection Agency (EPA), Region IV, asked ATSDR to review the Final Site Remedial Investigation Report for the Stauffer Chemical Company and determine if contamination at the site poses an imminent and substantial endangerment .
The site is an inactive facility that previously processed phosphate ore to produce elemental phosphorus. The plant operated from 1947 until it closed in 1981. Residual wastes from the recovery operation were disposed of in on-site disposal ponds and in the slag processing area. The facility is currently fenced and patrolled 24 hours a day by security guards. The Gulf View Elementary School is located directly north of the facility along Anclote Boulevard.
On-site surface soils (0-3 inches) are contaminated with inorganic and organic chemicals and radionuclides. In a 1993 study, the following maximum concentrations of contaminants were detected in on-site surface soils: arsenic 127 milligrams/kilogram (mg/kg), lead - 324 mg/kg, fluoride 2,810 mg/kg, and phosphorus - 27,600 mg/kg . Several polyaromatic hydrocarbons were detected at concentrations of < 4.3 mg/kg. On-site soil is also contaminated with elevated concentrations of radionuclides. The following maximum concentrations of radionuclides were reported for on-site surface soils: radium-226 (73.8 picocuries/gram [pci/g]), polonium-210 (203.3 pCi/g), and radon-222 (3 pCi/g) . In a 1989 survey, external gamma radiation readings as high as 140 microRoentgen/hour (AR/hr) were detected on-site.
Surface soils from the Gulf View Elementary School did not contain any organic or inorganic chemicals at concentrations of health concern. The low concentrations of radionuclides detected in surface soil samples from the school property (radium-226 (1.6 pCi/g], radon-222 (1.6 pCi/g], and polonium 210 [2.9 pci/g] were not at levels of health concern.
On-site groundwater from the surficial aquifer contained arsenic, lead, cadmium, fluoride, and chromium at concentrations in excess of the EPA's drinking water Maximum Contaminant Levels (MCLs). Radon-222 concentrations in water from the surficial aquifer also exceeded the proposed MCL, but the concentrations were less than the average radon concentration reported for groundwater in central Florida .
None of the chemical parameters measured in the deeper Floridan aquifer exceeded drinking water MCLs except for radon-222. The concentration of radon-222 was highest in an upgradient, background monitoring well, which suggests that the elevated radon levels are not site-related .
No potable wells are located on-site or down-gradient of the facility. The surficial and Floridan aquifers flow to the southwest and discharge to the Anclote River, which borders the site on the southwest. Surface water samples from the river did not contain contaminants at levels of human health concern.