TCE contamination at Woburn

Question 1

what determines direction of groundwater flow

Answer 1

-hydraulic head
- height of static water column above arbitrary elevation
- high hydraulic head to low hydraulic head flow

Question 2

What is the hydraulic gradient?

Answer 2

2 points is the slope of hydraulic head in between
- y distances diff/ x distances diff

Question 3

simple definition of hydraulic head

Answer 3

It is equal to the height of the water table

Question 4

is the woburn aquifer confined

Answer 4

Yes , we assume so

Question 5

how does groundwater flow

Answer 5

High elevation to low elevation
high to river

Question 6

what effect do pumping wells have on groundwater flow

Answer 6

they draw water towards themselves to make pressure gradient
rate of flow will increase
draw down water table

Question 7

what does groundwater flow velocity depend on

Answer 7

1. Hydraulic gradient
2. Permeability to rock or sediment

Question 8

Porosity meaning

Answer 8

measure of its ability to hold a fluid

Question 9

permeability meaning

Answer 9

measure of the ease of flow of a fluid through a porous solid.

Question 10

What do pumping wells create in unconfined aquifer

Answer 10

cone of depression

Question 11

woburn cone of depression zones

Answer 11

wells G and H

Question 12

What is flow net

Answer 12

representation of groundwater flow in a area

Question 13

what do blue lines present in groundwater flow

Answer 13

Equipotential lines

Question 14

what do red lines present in groundwater flow

Answer 14

Groundwater flow lines

Question 15

what is TCE

Answer 15

Trichloroethylene is a toxic chlorinated hydrocarbon

Question 16

what is TCE used for

Answer 16

• effective solvent for organic materials
• before was used to extract vegetable oils, coffee decaffeination, dry cleaning
• used to dissolve grease and oil

Question 17

Health effects of TCE

Answer 17

Carcinogenic in animals

Question 18

what industries were operating in woburn in the vicinity of wells G and H?

Answer 18

• close to boston: tanning and shoemaking
• leather production

Question 19

what raised concerns in woburn on their drinking water quality

Answer 19

• tasted and smelled weird whenever G and H got pumped

Question 20

Do most states now have cancer registries that provide an important
means of monitoring cancer rates

Answer 20

True

Question 21

Massachusetts did have a cancer registry when the
Woburn health concerns emerged in the late 1970’

Answer 21

False

Question 22

In the late 1970’s, it was not known if TCE ingestion was a
potential cause of childhood leukemia.

Answer 22

True

Question 23

It was possible to test for the presence of TCE in
groundwater prior to the late 1970’s

Answer 23

False

Question 24

A “cluster” of health-related concerns can be determined using
Standard Incidence Ratios (SIR)

Answer 24

True

Question 25

how does SIR do its job

Answer 25

compares number of observed cases of disease that is expected in that community to overall rate

Question 26

for age <5, what was expected case #

Answer 26

1.43

Question 27

for age 5-9, what was expected case #

Answer 27

0.82

Question 28

for age 10-14, what was expected case #

Answer 28

0.64

Question 29

what was the outcomes of Anne from woburn case about her kid’s cancer death?

Answer 29

Uni First 1.05M before trial
WR grace liable and Beatrice foods not liable
wr grace paid 8 million

Question 30

what did jury misunderstand about groundwater flow?

Answer 30

didn’t know groundwater could travel under river

Question 31

where is Woburn

Answer 31

Massachusetts US