Environmental Management II Semester Test II Memorandum

Environmental Management II

Semester Test 1

Date: March 17th 2009 Time: 2 hours Marks: 90 marks Initials and surname:   __________________________________   Student number:   __________________________________

Topics covered: Life Cycle Assessment 1.     What is life cycle assessment 2.    Goal and scope definition 3.    Inventory analysis 4.    Impact assessment   LCA 101 Document p1-24 and Integrated Environmental Management Series 9: Life Cycle Assessment

 

 

 

 

Question 1

 

Why is a life cycle assessment also called a Cradle to Grave assessment?

(6)

 

Answer 1

Life cycle assessment is a "cradle-to-grave" approach for assessing industrial systems. "Cradle-to-grave" begins with the gathering of raw materials from the earth to create the product and ends at the point when all materials are returned to the earth. LCA evaluates all stages of a product's life from the perspective that they are interdependent, meaning that one operation leads to the next. LCA enables the estimation of the cumulative environmental impacts resulting from all stages in the product life cycle, often including impacts not considered in more traditional analyses (e.g., raw material extraction, material transportation, ultimate product disposal, etc.). By including the impacts throughout the product life cycle, LCA provides a comprehensive view of the environmental aspects of the product or process and a more accurate picture of the true environmental trade-offs in product selection.

 

 

Question 2

 

What are the four steps you need to take when conducting a LCA? List and briefly describe each of the steps.

 

(4x2=8)

 

Answer 2

1. Goal Definition and Scoping - Define and describe the product, process or activity. Establish

the context in which the assessment is to be made and identify the boundaries and environmental

effects to be reviewed for the assessment.

2. Inventory Analysis - Identify and quantify energy, water and materials usage and environmental

releases (e.g., air emissions, solid waste disposal, wastewater discharge).

3. Impact Assessment - Assess the human and ecological effects of energy, water, and material usage

and the environmental releases identified in the inventory analysis.

4. Interpretation - Evaluate the results of the inventory analysis and impact assessment to select the

preferred product, process or service with

 

Question 3

 

What are three benefits of conducting a LCA?

(3)

 

Answer 3

An LCA will help decision-makers select the product or process that results in the least impact to the environment.

This information can be used with other factors, such as cost and performance data to select a product or process. LCA data identifies the transfer of environmental impacts from one media to another (e.g., eliminating air emissions by creating a wastewater effluent instead) and/or from one life cycle stage to another (e.g., from use and reuse of the product to the raw material acquisition phase). If an LCA was not performed, the transfer might not be recognized and properly included in the analysis because it is outside of the typical scope or focus of product selection processes.

 

 

Question 4

 

What are two limitations of a LCA?

(2)

 

Answer 4

Performing an LCA can be resource and time intensive. Depending upon how thorough an LCA the users wish to conduct, gathering the data can be problematic, and the availability of data can greatly impact the accuracy of

the final results. Therefore, it is important to weigh the availability of data, the time necessary to conduct the study, and the financial resources required against the projected benefits of the LCA. LCA will not determine which product or process is the most cost effective or works the best. Therefore, the information developed in an LCA study should be used as one component of a more comprehensive decision process assessing the trade-offs with cost and performance.

 

 

Question 5

 

What is goal definition and scoping?

(3)

 

Answer 5

 

Goal definition and scoping is the phase of the LCA process that defines the purpose and method of including life cycle environmental impacts into the decision-making process. In this phase, the following items must be determined: the type of information that is needed to add value to the decision-making process, how accurate the results must be to add value, and how the results should be interpreted and displayed in order to be meaningful and usable.

 

 

Question 6

 

Which six decisions need to be made in the goal and scoping definition step to make effective use of time and resources?

(6)

 

Answer 6

Getting Started

The following six basic decisions should be made at the beginning of the LCA process to make effective use of

time and resources:

1. Define the Goal(s) of the Project

2. Determine What Type of Information Is Needed to Inform the Decision-Makers

3. Determine How the Data Should Be Organized and the Results Displayed

4. Determine What Will or Will Not Be Included in the LCA

5. Determine the Required Accuracy of Data

6. Determine Ground Rules for Performing the Work

 

Question 7

 

Make a simple drawing to show the different stages in the life of a product. You need to go into somewhat detail in each step. If the step contains smaller steps you need to include them as well.

(10)

 

The four life cycle stages are explained in more detail below.

 

Raw Materials Acquisition

The life cycle of a product begins with the removal of raw materials and energy sources from the earth. For

instance, the harvesting of trees or the mining of nonrenewable materials would be considered raw materials

acquisition. Transportation of these materials from the point of acquisition to the point of processing is also

included in this stage (EPA 1993).

 

Manufacturing

During the manufacturing stage, raw materials are transformed into a product or package. The product or package

is then delivered to the consumer. The manufacturing stage consists of three steps: materials manufacture, product

fabrication, and filling/packaging/distribution (EPA 1993).

 

Materials Manufacture

The materials manufacture step involves the activities that convert raw materials into a form that can be

used to fabricate a finished product.

 

Product Fabrication

The product fabrication step takes the manufactured material and processes it into a product that is ready

to be filled or packaged.

 

Filling/Packaging/Distribution

This step finalizes the products and prepares them for shipment. It includes all of the manufacturing and transportation activities that are necessary to fill, package, and distribute a finished product. Products are transported either to retail outlets or directly to the consumer. This stage accounts for the environmental effects caused by the mode of transportation, such as trucking and shipping.

 

Use/Reuse/Maintenance

This stage involves the consumer's actual use, reuse, and maintenance of the product. Once the product is distributed to the consumer, all activities associated with the useful life of the product are included in this stage.

This includes energy demands and environmental wastes from both product storage and consumption. The product or material may need to be reconditioned, repaired or serviced so that it will maintain its performance (EPA

1993). When the consumer no longer needs the product, the product will be recycled or disposed.

 

Recycle/Waste Management

The recycle/waste management stage includes the energy requirements and environmental wastes associated with

disposition of the product or material (EPA 1993).

 

 

Question 8

 

What is a life cycle inventory? Provide a definition or answer in your own words.

(3)

 

Answer 8

A life cycle inventory is a process of quantifying energy and raw material requirements, atmospheric emissions, waterborne emissions, solid wastes, and other releases for the entire life cycle of a product, process, or activity

(EPA 1993).

 

Question 9

 

Why do you need to conduct a life cycle inventory?

(2)

 

Answer 9

In the life cycle inventory phase of an LCA, all relevant data is collected and organized. Without an LCI, no basis exists to evaluate comparative environmental impacts or potential improvements. The level of accuracy and detail of the data collected is reflected throughout the remainder of the LCA process.

Life cycle inventory analyses can be used in various ways. They can assist an organization in comparing products or processes and considering environmental factors in material selection. In addition, inventory analyses can be used in policy-making, by helping the government develop regulations regarding resource use and environmental emissions

 

 

Question 10

 

Name the four key steps in the life cycle inventory.

(4)

 

Answer 10

The two documents define the following steps of a life

cycle inventory:

• develop a flow diagram of the processes being evaluated

• develop a data collection plan

• collect data

• evaluate and report results

 

Question 11

 

Give four data sources commonly used to collect data in the life cycle inventory step.

(4)

 

Answer 11

Examples of data sources include the following:

·      • meter readings from equipment

·      C equipment operating logs/journals

·      C industry data reports, databases, or consultants

·      C laboratory test results

·      C government documents, reports, databases, and clearinghouses

·      C other publicly available databases or clearinghouses

·      C journals, papers, books, and patents

·      C reference books

·      C trade associations

·      • related/previous life cycle inventory studies

·      C equipment and process specifications

 

C best engineering judgement.

·      Examples of data types include:

·      C measured

·      C modeled

·      C sampled

·      C non-site specific (i.e., surrogate data)

·      C non-LCI data (i.e., data not intended for the purpose of use in a LCI)

 

 

Question 12

 

Name and very briefly explain the differences between the three types of LCA commonly conducted.

(6)

 

Answer 12

 

Life cycle thinking/Conceptual LCA

Only in your mind. Not on paper.

 

Simplified LCA

Generic information/ Not site specific information

 

Full LCA

Specific information. Most detailed.

 

 

Question 13

 

What is life cycle impact assessment? Provide a definition or answer in your own words.

(3)

 

Answer 13

The Life Cycle Impact Assessment (LCIA) phase of an LCA is the evaluation of potential human health and environmental impacts of the environmental resources and releases identified during the life cycle inventory (LCI). Impact assessment should address ecological and human health effects; it can also address resource depletion. A life cycle impact assessment attempts to establish a linkage between the product or process and its potential environmental impacts.

 

Question 14

 

Why do we need to conduct a life cycle impact assessment?

(2)

 

Answer 14

Although much can be learned about a process by considering the life cycle inventory data, an LCIA provides a more precise basis to make comparisons. For example, although we know that 9,000 tons of CO2 and 5,000 tons of methane released into the atmosphere are both harmful, an LCIA can determine which could have a greater potential impact. Using science-based characterization factors, an LCIA can calculate the impacts each environmental release has on problems such as smog or global warming. An impact assessment can also incorporate value judgements. In an air non-attainment zone, for example, air emissions could be of relatively higher concern than the same emission level in a region with better air quality.

 

Question 15

 

List the seven steps you need to perform when doing a life cycle impact assessment.

(7)

 

Answer 15

 

The following steps comprise a life cycle impact assessment.

 

1. Selection and Definition of Impact Categories - identifying relevant environmental impact categories

(e.g., global warming, acidification, terrestrial toxicity).

 

2. Classification - assigning LCI results to the impact categories (e.g., classifying CO2 emissions to global

warming).

 

3. Characterization - modeling LCI impacts within impact categories using science-based conversion

factors. (e.g., modeling the potential impact of CO2 and methane on global warming).

 

4. Normalization - expressing potential impacts in ways that can be compared (e.g. comparing the global

warming impact of CO2 and methane for the two options).

 

5. Grouping - sorting or ranking the indicators (e.g. sorting the indicators by location: local, regional, and

global).

 

6. Weighting - emphasizing the most important potential impacts.

 

7. Evaluating and Reporting LCIA Results - gaining a better understanding of the reliability of the LCIA

results.

 

 

Question 16

 

Classify the following chemical species into one of the following impact categories:

 

(Global warming, ozone depletion, acidification, eutrophication, photochemical smog, terrestrial and aquatic toxicity)

 

 

Simply write the correct category next to the question number.

 

16.1 Chloroflourocarbons

16.2 Carbon dioxide

16.3 Hydroflouric acid

16.4 Chromium (IV) ions

(4)

 

Answer 16

16.1 Ozone depletion

16.2 Global Warming

16.3 Acidification  

16.4 Aquatic or terrestrial toxicity

 

 

 

 

 

 

 

Total (73)