Module 3, Spring 1996

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INTRO

System Design - Risk Modeling and Assessment

PART I: Introductory Problem

You are a systems analysis team for "Dispose R Us, Inc." An electronics manufacturer located in Charlottesville, Virginia has requested a "Rough Order of Magnitude" estimate for the cost of transporting a toxic chemical waste from Charlottesville to an appropriate chemical waste treatment facility. The company will generate about 10 tons of waste per week. Federal regulations require that the material be stored no longer than 7 days at the Charlottesville site.

There are two facilities which can handle this type of waste. One facility is located in Magnolia, Arkansas. The other facility is located in Hornell, New York. You are assigned to develop a model which can be used to estimate the risks involved in shipping to the two facilities. Additionally, the cost analyst is away from the office for vacation and you have been assigned to estimate the costs of transportation. Preliminary recommendations are requested.

The following table lists the accident rates for some states in the eastern US. The numbers give the accident rates for trucks carrying hazardous material in accidents per 100 Million Miles traveled.

State Rate

NY - 40
PA - 38
NJ - 30
DL - 44
MD - 38
WV - 64
VA - 36
NC - 46
TN - 52
KY - 52
SC - 58
GA - 40
AL - 52
MI - 64
AK - 44
LA - 50

These numbers can be used as a baseline rate. You may wish to use adjustment factors below to consider how the accident rate changes depending on the type of road. (Rate as Percentage of Baseline Rate)

Rural Interstate: 0.85
Rural Highway: 0.95
Urban Highways/Interstate: 1.75
Small Town/City (<10,000 Residents): 0.50

The severity of the consequences was modeled in an earlier similar study by considering three outcomes:

No spillage: The material was not released into the environment.
- The required emergency response to secure the accident scene can be expected to cost $50,000.
Minor spill: Some material is released into the environment.
- Because of the very toxic nature of the material, 5% of the people within 5 mile radius will be killed and another 25% injured and requiring hospitalization. Clean-up is expected to cost $600,000.
Major spill: All material is released into the environment.
- 5% of the people within a 10 mile radius will be killed and another 25% injured. Clean-up is expected to cost $2.5 Million.

The probabilities of the three occurrences, given that an accident occurs is:

No spill: P= 0.70
Minor spill: P= 0.25
Major spill: P= 0.05

Cost Assessment:

Trucking the material will cost $0.25/ton-mile. One truck can handle the 10 tons.
Processing and disposal costs will be $100/ton in New York and $150/ton in Arkansas.

Part II: General Design

Dispose R Us, Inc., has asked each of their top design teams to develop a preliminary design of a generic hazardous waste routing system for the continental US. The system should allow the user to enter an origin and destination, and the system will provide the user with routing alternatives. Their goal is to develop a system that can be sold to numerous types of companies that ship hazardous waste. Dispose R Us, Inc., will select the best design for development.

Tentative Schedule

4 April - Systems Engineering and the Engineering Design Process
9,11 April - Introduction to Decision Analysis and Risk Assessment
16, 18 April - Venture Analysis and QFD

Part I:

Preliminary Analysis - 9 April - (informal presentations/discussion) - discuss your approach to the problem
Final Analysis: - 16 April - (formal presentations/discussion)
- turn-in formal analysis report (format to be discussed in class)
- present formal briefing to client (15 minutes total)

Part II:

Preliminary Design Discussion - 18 April - (informal presentations/discussion) - turn-in preliminary design document
Final Design: - 25 April - (formal presentations/discussion)
- turn-in formal design document (format to be discussed in class)
- present formal briefing to client (15 minutes total)