# Unit I Chemistry of hazardous materials question 11

*label*Chemistry

*timer*Asked: Jan 26th, 2016

**Question description**

I already answered some of the questions. I just need help in writing the essay. I am not sure if I am supposed to do a cost estimate also?

**You are the project manager of an environmental company that
was hired to cleanup a historical arsenic contamination site. Soil sampling results indicated the area
impacted with arsenic above action levels is 30 feet by 55 feet. The depth of
the arsenic plume is three feet below ground surface. The land owner wanted to
clean this site for future development. Using your textbook, answer the
questions below to help you prepare a cost estimate for this portion of the
project. Your solutions and any assumptions to justify
your estimate must be shown.**

**1. What is the chemical symbol of arsenic,
and what group/family does it belong to?**

The chemical symbol of arsenic is As. It belongs to group 15 or the Nitrogen Family.

**2. Solve for the minimum volume of soil
that will be excavated in cubic yards?**

Since the affected area with arsenic pollution was 30 feet by 55 feet by 3 feet. So the project manager should remove at least the affected area of the underground soil. (The formula used here will be of Volume which is a product of length, breadth and height).

The minimum volume of soil that should be excavated here would be (30*55*3)cubic feet =(30*0.33*55*0.33*3*0.33)cubic yards= 177.88 cubic yards (1 foot=0.33 yard)

**3. If each dump truck can transport 18
cubic yards, determine how many dump trucks loads** **will be transported? For calculation purposes, add a 15% fluff factor
(add to the volume that will be transported).**

The total volume of soil excavated= 177.88 cubic yards

Addition of fluff factor of 15% to the soil excavated= 204.57 cubic yards (177.88*1.15)

Volume of soil that can be dumped in one truck= 18 cubic yards

Number of trucks required: 12 (204.57/18=11.36, since the number of trucks

**4. If the bulk density
of soil is 1350 kg/m3 (84.3 lb/ft3), solve for the weight of the soil that will
be transported to a disposal site in kilograms.**

Volume of soil to transported in cubic meter is = 140.44 cubic meter (30*0.305*55*0.305*3*0.305) because 1 foot=0.305 meter

Given density= 1350 kg/cubic meter

Since density=mass/volume and we have to calculate the mass of soil for transportation based on above given data

Hence, Mass= Density*Volume

i.e. Mass of soil= 189600 Kg(1350kg/cubic meter*140.44 cubic meter)