Laserfiche WebLink
f) I1 <br /> CAMBRIA <br /> MASS BALANCE CALCULATION ASSUMPTIONS <br /> TPHG <br /> Volumes- Soil samples collected between 1989 and 1991 indicate that soil was impacted by TPHg <br /> in the vicinity of the former USTs and both dispenser islands To calculate the mass of TPHg in soil, <br /> Cambria assumed that the volume of impacted soil near the former USTs can be represented by an <br /> ellipsoid with a d, of 36 feet, a d2of 20 5 feet, and a thickness of 20 feet The volume of impacted <br /> soil near the western dispenser can be represented by a cylinder with a diameter(di and d2) of 4 feet <br /> and a thickness of 10 feet The volume of impacted soil near the eastern dispenser can be represented <br /> by a cylinder with a diameter of 8 feet and a thickness of 10 feet These areas are shown on the <br /> attached map <br /> Representative Concentrations: An average of all soil samples collected in the former UST area was <br /> used as the representative concentration of the ellipsoid For non-detect samples located within the <br /> ellipse, a value of 1 ppm(a typical detection limit)was used as the concentration The concentration . <br /> detected in sample TR-1 was used as the representative concentration for the entire cylinder near the <br /> western dispenser An average of the concentration detected in sample TR-2A and 10 ppm(from the <br /> iso-concentration map in Attachment F)was used as the representative concentration of the cylinder <br /> near the eastern dispenser <br /> BENZENE <br /> Volumes Soil samples collected between 1989 and 1991 indicate that soil was impacted by benzene <br /> in the vicinity of the former USTs and near boring B-4 To calculate the mass of benzene in soil, <br /> Cambria assumed that the volume of impacted soil near the former USTs can be represented by an <br /> ellipsoid with a d, of 48 feet,a dz of 27 feet, and a thickness of 20 feet The volume of impacted soil <br />