DISCUSSION
The highest surface water and sediment contamination is located in the wastewater ponds found at the two facilities (see Tables 1 and 2). Analytical results of samples taken in the Portneuf River have demonstrated that the FMC discharge has not resulted in any significant contamination of the river (i.e., no contamination was found at levels of health concern) (see Tables 3 and 4).
Because of the location of the ponds and the operational procedures used (e.g., site restrictions), it is doubtful that the general public would come in contact with the contaminated surface water and sediment contained in the ponds. In addition, no contamination at levels of health concern was found in the Portneuf River. Therefore, it is very unlikely that the general public's health has been or will be impacted by any of the surface water or sediment contamination found at the Eastern Michaud Flats Contamination NPL site.
The only people who may come in contact with contaminated surface water and sediment are workers at the FMC and Simplot facilities (specifically workers responsible for the operation of the wastewater ponds). However, the length and frequency of contact with contaminated surface water and sediment is probably very short and infrequent. The wastewater operating procedures used at the facilities do not require frequent or intensive human involvement. Normal occupational safety procedures (e.g., wearing of safety gear -- gloves and eye protection) would further reduce the possibility of workers ingesting contaminated surface water and sediment. In addition, the level of contamination found in the on-site ponds are not at levels that could result in health impacts after a one time exposure (i.e., accidental ingestion). Therefore, it is doubtful that FMC or Simplot workers have been or will be exposed to any significant amounts of contaminated surface water or sediment that could impact their health.
CONCLUSIONS
Based upon the data and information reviewed, the Agency for Toxic Substances
and Disease Registry has drawn the following conclusions:
ATSDR makes the following recommendation:
Appropriate worker safety procedures should continue to prevent workers from accidentally ingesting contaminated surface water and sediment.