WORK PLANS - Laserfiche WebLink

Home Browse Search

� -2- A quantitative risk assessment could not to generated because no exposure concentration data was available �o determine a dose. Comments 1 . The report references CH2M Hill Comr-.:nity Relations Plan, 1987 , as stating that there are no threatened or endangered species and no area of unique habitat. This finding could not be found in the stated reference. More importantly, the PHERA should develop this analysis and not base the conclusions on a general information document. 2 . Another exposure pathway which shall be evaluated, is the ingestion of fish caught in the New and Old Mormon Slough. Recent sediment testing concluded that low levels of metals and non-detectable levels of organics were found. However, fish may concentrate levels of contaminants in their body tissues far above sediment levels. 3 . Another potentially exposed population may include the "family" from contaminants which are tracked home. 4 . Complaints have been received by OSHA regarding emissions from the facility. In response, OSHA has conducted sampling at the facility. Efforts to retrieve this data should be made and evaluated in the final report. 5 . Exposure to contaminants for workers at the Stockton Wastewater Treatment Facility may be low because of dilution. While exposure may be limited, work performed with the sewer lines prior to the dilution point should be evaluated. 6 . Further details concerning air sampling of workers completed in 1986 should be presented. The required information includes: 1) how many episodes of sampling were performed; 2) what were the tasks performed by workers each day; 3) what were weather and soil conditions; and 4) methods and rates of sample collection. 7 . The report states that soil contaminant concentrations are negligible, in comparison to chemical exposure from the treatment operation. The highest worker air sample result for arsenic was 0. 8 ug/m3 . Exposure to offsite workers downwind from fugitive dust was calculated to be 3 . 1 ug/n3 . A reassessment of exposure to onsite workers from dust should be made. Particulate sampling for metals at several onsite locations and the perimeter of the property should be performed. 8 . Confirmation on concentrations of organics in the air (vapors, dust) at this site should be performed rather than relying only on past federal studies.