Terminology: sorption, retardation, nonaqueous phase liquids (NAPLs), LNAPs, DNAPLs, benzene, MTBE, industrial solvents, TCE, PCE, downgradient, upgradient, groundwater plume, contaminant transport, retardation, travel time, zone of influence, capture zone
SUBSURFACE POLLUTION SOURCES
·
At the release point, chemicals can be in differing forms
depending on
o the
melting point, boiling point of the chemical and
o the
possible presence of the contaminant in a mixture
·
Waste forms are
o Solids
o Pure
Chemical (also called NonAqueous Phase Liquid or NAPL)
o Vapor or
gas
o Contaminant
dissolved in water
SORPTION
·
Some chemicals have a tendency to adsorb and desorb on and
off of sediments (sorbing contaminants)
·
Strongly sorbing compounds will be soil or sediment
pollutants
o Will tend
to remain near surface in soil zone
o Will not
produce extensive groundwater contamination
o Will be
deposited in stream, lake and bay bottoms
o Include
polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs)
o Include
many metals (unless extreme pH conditions are present)
·
Nonsorbing compounds will move with water
·
Low to medium sorbing compounds will move with water but at
a slower velocity è called
Retardation
NonAqueous Phase Liquids (NAPLs)
·
NAPL will move as a pure chemical liquid through the
subsurface
·
How far below the surface a NAPL will penetrate is
controlled by
o the
permeability of the subsurface and
o the
density of the NAPL relative to water
·
Light NAPLs have densities less than water
o Gasoline
o Diesel
fuel
o Jet fuel
o If spilled
on surface, will move downward through the unsaturated zone leaving behind
small amounts of NAPL in the pore spaces
o In contact
with water, less dense material will float on top
o Oil on
water
o Will not
penetrate significantly past the water table
o However,
chemical components CAN dissolve into groundwater and be carried downgradient
producing a groundwater plume
o Soluble
components of gasoline include benzene and MTBE (a gasoline
additivie)
·
Dense NAPLs have densities greater than water
o Industrial
solvents used as degreasers (common in any industry cleaning metal parts – Lots
of those!), dry cleaning, etc.
o Trichloroethene
(TCE)
o Tetrachloroethene
or perchloroethene (PCE)
o If spilled
on the surface, will move downward through unsaturated zone leaving behind
small amounts of NAPL in the pore space
o If enough
volume of DNAPL is spilled and permeability permits, DNAPL will penetrate past
the water table and continue moving downward into the saturated zone due to
gravity effects
o Chemical
constituents of DNAPL will dissolve into groundwater and produce a groundwater
plume downgradient
DISSOLVED CHEMICAL TRANSPORT
·
Dissolved chemicals (solutes) will travel with flowing water
o Groundwater
flow calculated from Darcy’s Law
o V = K
dh/dl divided by porosity
o Example: K = 100 ft/day, dh/dl = 0.001, porosity
= 0.25 v = 100 ft/day X 0.001 / 0.25 = 0.4 ft/day
·
Travel time = length of time for a dissolved chemical to
travel a certain distance
o Example: Source area is 100 ft upgradient of stream
o If v = 0.4
ft /day,
o Travel
time = 100 ft/0.4 ft/day = 250 days
·
If a contaminant is retarded in its transport due to
sorption, the retardation factor, R, can be estimated or measured
o Example: MTBE R = 1.0, benzene R = 2.0
o The
velocity of the retarded contaminant is v/R
o Velocity
of MTBE = v/1.0 = 0.4 ft/day
o Velocity
of benzene = v/2.0 = 0.2 ft/day
o In above
example,
§
MTBE would arrive at stream in 250 days
§
Benzene would take 2X as long (500 days)
EPA TOP ENVIRONMENTAL STORIES
·
1982 Toxics Found in Silicon Valley Groundwater
·
1983 Groundwater Contamination in San Fernando, San Gabriel
Valleys (Los Angeles). Sites added to NPL list
·
1997 EPA joins Santa Monica MTBE Enforcement Action
WHO CONTAMINATED THE WELL?
·
What information do we need?
·
Remember Darcy’s Law, v = K dh/dl / porosity
·
Need knowledge of the geology of the region
o Drill
holes and sample sediment or rock
o Unfractured
bedrock, clay layers = impermeable
o Sands,
gravels = permeable
·
Can guess from previous studies what hydraulic conductivity
(permeability) of the sediments/rocks are
·
Can measure K from monitoring water flow and hydraulic head
(potentiometric) conditions in the laboratory (permeameters) or in the field
(hydraulic tests, most common is called a pump or pumping test)
·
Need knowledge of the water levels (potentiometric levels)
in the aquifer
o Install
monitoring wells in numerous locations
o Measure
water levels
o Make water
level contour map
WATER LEVEL CONTOUR MAP
·
Remember from our Groundwater Basics section, groundwater
flow direction is from high water level (contour) to low water level (contour)
·
Draw groundwater flow lines at right angles (perpendicular)
to groundwater contour lines on your map
·
This will tell you the direction of groundwater flow and
contaminant transport
TRAVEL TIME
·
Once you have the direction of transport, the next question
is usually “How long will it (or did it) take to get from point A to point B?”
·
Remember Darcy’s Law
v = K dh/dl / porosity
o We have
dh/dl = change in water level over a unit distance from our contour map
o We have
information on the aquifer material from our geologic studies (K, porosity)
o Calculate
groundwater velocity from the above equation
·
Measure travel distance from map and calculate travel time
using your velocity
·
Same as how long it takes to get to Disneyland (100 miles
distance) if your Porsche velocity is 100 miles per hour è Travel
time = 1 hr
RETARDATION
·
For sorbing contaminants, a retardation factor, R, must be
estimated
·
Sorbing velocity = v/R
·
Say your driving in an old Chevy (R of 3). It will only go 1/3 rd the velocity of the
Porsche (33 miles per hour). It’s
travel time to Disneyland would be 3X as long è 3 hrs
HETEROGENEITY
·
Homogeneous conditions occur when your aquifer is made of a
uniform material (all coarse sand)
·
What if geologic conditions change along the travel path?
·
Heterogeneous conditions occur when your aquifer is made of
many differing geologic materials (more the rule than the exception)
·
Example:
SourceX----10 ft sand------X-----10 ft silt----------Xwell
·
You can apply Darcy’s Law in segments
o V in sand
= 10 ft/day, travel time through 10 ft of sand is 1 day
o V in silt
= 1 ft/day, travel time through 10 ft of silt is 10 days
o Total
travel time = 1 day + 10 days = 11 days
REAL LIFE
·
Hydraulic gradients may not be constant (equal spacing
between contours) particularly when wells are pumping in the aquifer
·
Extremely complex geology can make simple applications of
Darcy’s Law difficult
·
è Computer
models used applying Darcy’s Law under these complex scenarios
HYDROGEOLOGISTS AND THE LAW
·
Most pollution cases end up in litigation
o Suing to
discern who is a principle responsible party (PRP) under Superfund
o Civil
cases suing for injuries
·
Limited time and monetary resources
·
May not always have all the information necessary
·
Both sides (plaintiffs and defendants) have their own expert
witnesses (geologists, hydrogeologists, etc.)
·
Expert witnesses can have completely opposite
interpretations of the data (for the $, not trained for correct interpretations
or not enough data)
WOBURN, MASSACHUSETTS
·
Small city (36,000 people) about 12 miles northwest of
Boston
·
Long history of chemical manufacturing and leather tanning
·
Wells G and H developed by Woburn in 1964 and 1967
·
Approximately 30% of city’s water supply from these wells
·
Water delivered primarily to East Woburn
·
Residents immediately complain about taste and odor problems
·
Local records indicate water had high concentrations of
manganese, iron and chlorination causing unpleasant taste and odor BUT SAFE TO
DRINK [However, did they have the instrumentation to properly test for organic
compounds?]
·
James Anderson (son of Anne Anderson) born 1968
·
James Anderson diagnosed with leukemia in January 1972
·
Mid to late70s, local community concerned over incidence of
childhood leukemia (particularly near Pine St in East Woburn)
·
1979, 184 55-gallon drums containing polyurethane and
toluene dissocyanate were found on a vacant lot (drums later removed by unknown
parties during negotiations with Massachusetts Dept. of Environmental Quality
Engineering (DEQE)
·
Incident caused DEQE to sample nearest downgradient water
supply (Woburn’s Wells G and H)
·
Several chlorinated volatile organic contaminants (including
TCE and PCE) were detected in the well water (1 to 400 ppb)
·
Wells G and H shut down May 21, 1979
·
Statute of limitations for civil injury cases starts with
the shut down of wells. Have 3 years to
file a suit (till May 1982)
·
Members of local community suspect leukemia linked to well
water
·
Massachusetts Dept. of Public Health (MDPH) begin
investigating (Dec 1979). Confirm
higher than expected rate of leukemia (April, 1980)
·
1980 Superfund enacted
·
1981 EPA investigates groundwater contamination
·
January 1981, James Anderson dies
·
1982 Site proposed for NPL (Superfund). Ranked 39th
worst on list of 1100 sites
·
8 days before statute of limitations expired, May 1982, 8
families file a civil suit against 2 companies (Beatrice and Grace) as possible
polluters
·
1983 EPA orders 3 property owners (Grace, Beatrice,
Unifirst) to study groundwater and soil contamination
·
April 1985, another suit against a 3rd company
(Unifirst)
·
1985 Full-blown EPA (USGS) investigation of entire 330-acre
site (over 150 wells eventually installed)
·
October 1985, Unifirst settles out of court for $1 million
(money used to finance trial – Schlichtman & Co. had already spent almost
$1 million)
·
EPA/USGS conduct 30-day pumping test of aquifer from
December 1985 to January 1986.
Preliminary data available to expert witnesses however official USGS
report with conclusions is not published until 1987
·
Civil trial starts March 10, 1986 after court’s ruling on
several motions and 4 years of discovery (legal term)
·
6 member jury hears 77 days of testimony and has 1 day field
trip to site
·
Jury deliberates for 2 weeks
·
6 plaintiffs died by trial time (jury does not know this)
·
Verdict announced on July 28, 1986
·
1995 Publication of book, “A Civil Action” by Jonathan Harr
·
1999 Movie “A Civil Action” starring John Travolta
·
You will find out in the movie what happens but remember
trial is before official EPA ruling on PRPs (1988) and final USGS report on
pumping test (1987)
·
Will preview the hydrologic evidence as known now
·
Will show the expert witness testimony
WOBURN SITE
·
Wells G and H completed in the Aberjona aquifer
·
Aquifer is mixture of alluvium (stratified drift) and
glacial till on granitic or gabbroic bedrock
·
Bedrock valley cut into fractured igneous and metamorphic
rocks
·
è buried
valley filled with glacial deposits
o glacial
till = sediment deposited after transport in ice
o alluvium
(stratified drift) = sediment deposited from glacial meltwater
·
Aberjona River flows through valley and is underlain by peat
deposits
·
Groundwater flow direction and magnitude depends on whether
Wells G and H are pumping or not pumping
WOBURN POSSIBLE POLLUTORS
·
Industriplex site – another NPL site located less than 1
mile upstream of Wells G and H
Other sites closer to Wells:
·
Beatrice Foods (Riley tannery site later renamed Wildwood
Conservation Corporation)
·
W.R. Grace and Co. (Cryovac division)
·
Unifirst Corp (formerly Interstate Uniform Services Corp)
·
Olympia Nominee Trust (trucking company)
·
New England Plastics
·
September 1988, EPA concludes study that all 5 properties
had groundwater contamination
o Groundwater
contaminated with volatile organic compounds (VOCs) including TCE, PCE
o Sediments
in river contaminated with polynuclear aromatic hydrocarbons (PAHs) and heavy
metals (chromium, mercury, arsenic) from old waste lagoons and disposal piles
at the Industriplex site
o Soils
across 330-acre site contaminated with PAHs, polychlorinated biphenyls (PCBs),
VOCs and lead
·
1991, 5 parties agree to a $70 million cleanup
BEATRICE PROPERTY (RILEY TANNERY)
·
Located southwest of wells
·
Tannery and infamous “15 Acres”
·
Beatrice Foods purchased tannery in 1979 (year that
contamination was discovered). Talk about luck!
·
Today property is owned by Wildwood Conservation Corp
·
Contaminated soil, sludge piles and decaying drums removed
beginning in 1995 (almost 10 years after trial!)
NEW ENGLAND PLASTICS COMPANY
·
High concentrations of PCE in soil beneath a storage trailer
owned by a former tenant, Prospect Tool & Die
·
Water table at depth of 6 to 9 feet
OLYMPIA NOMINEE TRUST
·
Trucking depot
·
Drums and debris
W.R. GRACE COMPANY
·
Cryovac Plant closed in 1995
·
2 “hot spots” exist. One next to the backdoor (easy dumping)
·
Several buried drums
·
TCE and DCE in groundwater
·
3.9 gallons of pure chemical collected in remediation
UNIFIRST PROPERTIES
·
TCE and PCE have moved downward through thin glacial
sediment into fractured bedrock
·
Since 1992, 105 gallons of pure product collected
15 ACRES
·
Undeveloped land northeast of tannery
·
Purchased in 1950s by tannery for water supply
·
Tannery accused of contaminating groundwater at this
location
LOTS OF POTENTIAL SOURCES
·
W.R. Grace manufacturing plant 2,400 ft northeast of wells
·
Beatrice Foods responsible for tannery contamination on 15
acres located 700 ft southwest of wells G and H
·
UniFirst dry cleaning business about 2,000 ft north of wells
FIELD EVIDENCE
·
Preliminary EPA report accessible to lawyers showed
o Northeast
of wells – plume of TCE migrating towards Wells G and H
o Even
higher concentrations of TCE found in groundwater to the west of the two wells
(15 acres site)
·
No principal responsible parties (PRPs) identified by EPA
yet
LAWYERS, JUDGE, EXPERT WITNESSES
·
Jan Schlichtmann for the plaintiffs
·
Judge Walter Skinner
·
Expert for plaintiffs:
o Geologist
John Dobrinski – conducted field investigation, well installation, sampling
soil and water, reviewing old aerial photos (showing stacks of barrels on the
15 acres)
o Hydrogeologist
George Pinder – analyzed data and set up groundwater flow model
·
Expert for plaintiffs:
o John Guswa
3-STEP TRIAL
·
1st phase – must decide whether Grace or Beatrice
contaminated wells
·
2nd phase – plaintiffs must show that exposure to
contaminated well water resulted in the leukemia cases and other illnesses
·
3rd phase – damages would be set
·
separation into phases decided by judge
·
plaintiffs (families) could not be present at the 1st
trial (technical hydrogeology) because they were potential witnesses for the 2nd
phase
·
jury would not see plaintiffs before rendering a verdict in
1st phase
USGS PUMPING TEST
·
Wells G and H pumped for 30-days
·
Water levels in over 100 wells monitored before and during
pumping test
·
Stream discharge in the Aberjona River was measured before
and during pumping test at positions upgradient and downgradient of wells
·
Streamflow upgradient – Streamflow downgradient = 0 means no
loss or gain of water from river
·
Streamflow upgradient – Streamflow downgradient = + number
means Flow In > Flow Out
o Where did
the water go?
o Into the
groundwater è losing
stream
·
Streamflow upgradient – Streamflow downgradient = - number
means Flow Out > Flow In
o Where did
the extra water come from?
o Flow from
groundwater into stream è gaining
stream
·
During nonpumping conditions è gaining stream
·
During pumping conditions è losing stream (several hundred
gallons per minute of water lost along measured stream reach)
·
Drawdown pattern from well pumping shows zone of influence
or capture zone (where water pumped from wells originates)
·
Can trace groundwater flowpaths on contour maps and identify
possible contaminant sources
PINDER’S TESTIMONY
·
TCE spilled on ground of W.R. Grace site would reach wells G
and H 3 years later
·
TCE dumped on 15-acre site (Beatrice) would arrive at wells
within 6 months
·
PCE travels about three times more slowly than TCE (remember
retardation)
CONFRONTATION ASPECT OF TRIALS
·
Dobrinski was attacked by defendant’s lawyer as he
previously lied in two job searches about the date of award for his M.S. degree
(said he had been awarded the degree when he hadn’t yet)
·
Lawyer sprayed numerous household substances into
Dobrinski’s face that contained many of the chemicals named in the complaint
·
Pinder miscalculated the velocity of groundwater in his head
in the trial box and forgot to factor in the porosity of the sediment (mistake
actually would have the contaminants arriving at a later time è possible
benefit to defendants BUT did not change times significantly)
·
Defense lawyers notice mistake and can use to attack credibility
of witness
·
Defense lawyer “treated him in a most contemptible manner,
addressing him in an insulting and scornful tone”
o “Are you
telling this jury that you came in here yesterday, as a Ph.D. and the chairman
of a department, and made a LITTLE mistake in an opinion you’ve been preparing
for the last year and half?”
·
The Aberjona River was being used by the defense as a
possible barrier to TCE contamination coming from the 15 acres, under the river
and to wells G and H
o Argument
is that wells G and H would draw all the water needed from the river and not
draw any water from the opposite side of the river bank
o Pinder’s
model with a very permeable sand and gravel layer showed that water would flow
under the river to the wells [He was right about this]. He believed the peat under the river was so
impermeable that no significant quantities of water would be drawn from the
river [He was wrong about this].
o He based
his opinion on the water level data but must not have reviewed the stream flow
data
o Schlichtman
was concerned with his expert’s explanation.
They stay up till midnight before day of testimony trying to figure out
o Pinder
testifies that he thought of in the shower that morning:
§
Water levels in river had gone down because groundwater was
no longer flowing into river (with wells pumping)
§
River was not losing water but was also not gaining water
§
Once again, he did not address the stream flow measurements
o Schlichtman
had sent the USGS flow measurements to Pinder along with several boxes of other
documents. Pinder had overlooked the
measurements.
o Mistake
caught by defense attorneys
o Judge:
“You have a hopeless witness who changes from A to B”. Disparages the “shower epiphany”
·
Grace’s expert witness, John Guswa, testified that the
glacial till under the Grace plant was so impermeable that it could not have
contributed significant amounts of contaminated water to Wells G and H
o Guswa
testifies to a groundwater recharge rate and how much flow would pass through
soil at Grace site
o Plaintiff’s
lawyer uses Darcy’s Law to show that the recharge flow rate would be impossible
with the low permeability (K) value, measured hydraulic gradient and amount of
area è equation
did not balance
o “Grace
plant would be submerged under a lake of water ten feet deep”
JUDGE’S QUESTIONAIRE
·
Skinner requires jurors to answer 4 questions for each
defendant
·
1: Had the plaintiffs established a preponderance of
evidence that any of the following chemicals – TCE, PCE, and 1,2-DCE – were
disposed on land after August 27, 1968 (Beatrice site) and October 1, 1964
(W.R. Grace site) and had these chemicals substantially contributed to the
contamination of the wells before May 22, 1979?
·
2: If yes to 1, What, according to a preponderance of the
evidence, was the earliest date (month and year) at which each of these
chemicals had substantially contributed to the contamination of the wells?
·
3: Had the contamination occurred because of the defendant’s
failure to fulfill any duty of care due to the plaintiffs?
·
4: If yes to 3, What, according to a preponderance of the
evidence, was the earliest time (month and year) at which the substantial
contribution referred to in question 3 was caused by the negligent conduct of
this defendant?
·
Could you understand the questions?
·
Answers unknowable. Science could not determine the moment
when chemicals arrived in wells by the month and year
·
Case would have to end if the jurors could not answer
questions based on evidence given?…
·
Stay tuned for the movie, “A Civil Action”, next week
ERIN BROCKOVITCH
·
Hinkley, California, Pacific Gas and Electric (PG&E)
operates a natural gas compressor station since 1952 (part of natural gas
pipeline)
·
1987, PG&E notifies Regional Water Quality Control Board
of chromium contamination in several wells
·
1993, 650 plaintiffs sue PG&E for hexavalent chromium
(also called chromium 6) contamination and health effects
·
Hexavalent chromium was used as a rust inhibitor and
discharged to unlined ponds from 1952 to 1966
·
Ponds lined in 1972 after regulations set
·
Hexavalent chromium blamed for many health effects –
nosebleeds, birth defects, rashes, immune disorders, uterine and breast cancer
·
1st 36 plaintiffs win in arbitration – plaintiffs
had to
o prove
medical causation
o deal with
missing evidence that had been lost or destroyed
o reconstruct
a complex hydro-geological water system
o prove the
extent of PG&E’s inappropriate conduct
·
PG&E settles out of court for $333 million ($2 million
to Erin)
CHROMIUM
·
Trivalent chromium is slightly soluble in water and an
essential element for nutrition
·
Hexavalent chromium is water soluble and considered toxic
(CA suggested limit is 50 ppb, Federal is 100 ppb)
·
Used in stainless steel and as rust inhibitor
·
Hexavalent chromium only known to cause nose and lung cancer
upon inhalation (fumes from welding, etc.)
RIGOROUS SCIENTIFIC QUESTIONS (Reason Magazine)
·
Are people who drank water from a suspect source sicker than
comparable populations elsewhere?
·
If so, do they suffer from a particular, distinctive set of
recurring symptoms? (such as mercury-induced “Minimata disease” in Japan)
·
Was the chemical exposure heavy, or something measured in
parts per million or billion, only slightly above a threshold drawn to err on
the side of extreme caution?
·
And if the latter, are claims of injury from minor exposure
consistent with what’s known to happen to worker or others who get exposed to
much higher concentrations of the same substance?
NOW EVERYONE IS LOOKING FOR CHROMIUM-6
·
Law firm, Masry and Vitoe (from movie), tested tap water in
Thousand Oaks and Agoura Hills. Found
2 ppb chromium-6 (still below MCL).
·
Mike Antonovich (assemblyman) pushes for more testing and lower
limits in CA
CRITICISMS OF “BROCKOVICH” CASE
·
Prove of health effects
·
Held onto settlement money for a long time (see Reason)
·
Money awards to Hinkley residents seemed arbitrary (see Reason)
·
Law firm involved with arbitration took judges on expense
cruise trip after trial (see Reason)
·
Michael
Fumento’s criticisms with extra links at bottom of his page
·
Why did PG&E settle out of court? (see Reason)
BROCKOVICH
AND SCHLICHTMANN NOW according to Dan Kennedy, a reporter with a distinct
bias against Schlichtmann
FALLON, NEVADA CANCER CLUSTER?
·
Small farming and military town
·
11 children diagnosed with leukemia; 8 diagnosed within last
year
·
Naturally occurring arsenic in the water wells
·
Concentrations of 100 ppb
·
Some families drank bottled water
·
“From the city’s point of view, we’ve had arsenic in the
water forever. We haven’t had a
leukemia cluster forever.” Assemblywoman for district
MARIN, CA AND MTBE
·
Upscale homes ($579,000 to $640,000) built over a MTBE plume
·
Buyers, sellers and regulators believe safe as
o Not a
drinking water source
o Property
owners sign a disclosure statement stating “there may be a risk to construction
workers from potential exposure to soil and groundwater and to residents who
ingest fruits and vegetables grown in areas situated above the MTBE plume”
o
Also advises
them not to plant deep-rooted fruit trees
WOULD YOU LIKE TO BE A GUINEA PIG?
Volunteers ingesting perchlorate for health effects study (paid $1,000)
SOURCES OF
GROUNDWATER POLLUTION
PROGRAMS FOR
GROUNDWATER PROTECTION
Woburn Case
with photographs and USGS reports
New England
EPA Information on Wells G and H and Settlement
http://www.civil-action.com/facts/keydocuments/tarrrpt.html
Death
and Justice (1999) by Daniel D. Kennedy (reporter for Woburn newspaper at time
of trial) – summary and commentary on case before, during and after trial
http://ehpnet1.niehs.nih.gov/docs/1997/105-10/rogers.html
San Gabriel Valley Superfund Site
San Fernando Valley Superfund Site
REFERENCES
Harr, J. (1995) A Civil Action. Vintage Press.