Title: Introduction to Phytoremediation
1Introduction to Phytoremediation
- EPA/600/R-99/107
- February 2000
- http//clu-in.org/download/remed/introphyto.pdf
2Phytoremediation Overview
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4Phytohydraulics
5Phytodegradation
6Phytoextraction
7Phytostabilization
8Phytovolatalization
9Rhizodegradation
10Rhizofiltration
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12Phytoremediation practice
Normal plant
Engineered plant thrive on arsenic
Poplar trees
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21Phytoremediation of Selenium by two helophyte
species in subsurface flow constructed
wetland. Shardendu, N. Salhani, S.F. Boulyga, E.
Stengel Chemosphere 50 (2003) 967-973
22Key Species in Study
- Phragmites australis
- Known as the Common reed
- Native to Florida
- Very large grass (up to 16 feet tall)
- Grows in colonies in several feet of water or
along moist shores (Florida, 2002).
23Key Species in Study
- Typha latifolia
- Common Cattail
- Can be up to 10 feet tall
- Found nearly worldwide
- Can be found almost anywhere soil remains wet,
saturated, or flooded most of the growing season
(Typha, 2002).
24Constructed Wetlands
- Defined as a designed and man-made complex of
saturated substrates, emergent and submergent
vegetation, animal life, and water that simulates
natural wetlands for human use and benefits."
(Hammer, 1989) - Constructed wetlands is one method used to help
purify wastewaters.
25Constructed Wetlands
26AMOVA Facility
Fig. 1. Outline of the experimental device for
tap layer supplying with sodium selenate
(Na2SeO4) in one vegetated bed with sampling
points (AMOVA facility).
27Inductively Coupled Plasma Mass Spectrometer
(ICP-MS)
Plasma, Argon gas, is used to atomize and ionize
the elements in a sample. The resulting ions are
then passed through a series of apertures (cones)
into the high vacuum analyzer. The isotopes of
the elements are identified by their
mass-to-charge ratio (m/e) and the intensity of a
specific peak in the mass spectrum is
proportional to the amount of that isotope
(element) in the original sample.
28What is Selenium?
- Naturally occurring element
- Found in most rocks and soils combines with
silver, copper, lead, and nickel minerals - Metallic gray to black hexagonal crystals
- Most selenium is processed for the electronics
industry, then for a nutritional supplement - Also used as a nutritional feed additive for
poultry and livestock, pesticide formulations,
rubber production, antidandruff shampoos, and
fungicides. (ATSDR, 2001)
29Why is Selenium Harmful?
- Low doses of selenium are necessary for
maintaining good health - Chronic Oral Exposure of high levels of selenium
can cause the disease, selenosis. - The major symptoms are hair loss, brittle nails,
neurological abnormalities - Most laboratory studies show that selenium
probably does not cause cancer. In fact,
studies have shown that lower than normal
selenium levels in the diet might increase the
risk of cancer. - EPA has determined that selenium sulfide is the
only form of selenium that might be a human
carcinogen. - EPA restricts public drinking water to 50 ppb and
OSHA restricts workroom air to 0.2 mg for an
8-hour shift.
(ATSDR,
2001).
30Selenium Migration over Time
Fig. 2. Profile of selenium migration on first
day (May 31, 1999) from inlet to other points
and outlet in Phragmites, Typha (a) and gravel
bed (b). Sampling points 1, 2, 3 and 4, inlet
(I) and outlet (O).
31Selenium from Inlet to Outlet Over Time
Fig. 3. Inlet and outlet selenium concentration
with time duration in Typha and Phragmites beds
during full experiment period.
32Selenium Concentration Profiles
Fig. 4. Selenium concentration profiles(n12)
with RSD along the bed length in Typha,
Phragmites and control bed. () Under detection
limit (0.05 g Se/l).
33Oxygen Concentration, Water Temperature, and pH
Fig. 5. Course of mean (n7) oxygen concentration,
water temperature and pH values (a, b, c) with
RSD values and corresponding Se concentration at
different sampling points along the beds of
Typha, Phragmites and gravel control.
34Bioaccumulation
Fig. 6. Bioaccumulation of Se in belowground
(organic material, roots, rhizomes) and
aboveground (stems, leaves) parts of the plant
species at segment S1 and S4 (a) Se content in
Typha control (b) Se content in Phragmites
control (c) Se content in Typha after 65 d and
(d) Se content in Phragmites after 65 d. ()
Under detection limit (0.4 g Se/g dry matter).
35Conclusions
- Phragmites is better equipped to uptake selenium
in subsurface flows. - The density of Phragmites was about 7 times
higher than the Typha. This explains why the
flow of water through the Typha was so much
quicker. - Selenium concentration was undetectable 3/4 into
the Phragmites bed. - 54 of the original selenium concentration was
measured at the Typha outlet - Phragmites accumulated selenium in its stems and
leaves while the Typha held the selenium in its
roots and rhizomes. This is important for
harvesting techniques in the most economic and
least destructive way. - 5) The oxygen concentration and pH value for
Phragmites decreased at a higher rate over the
course of each bed than the values for Typha
36References
- Aquatic Wetland and Invasive Plant Particulars
and Photographs. University of Florida.
http//aquat1.ifas.ufl.edu/phraus.html. 2002 - USEPA, 2001, EPA 542 www.epa.gov/superfund/sites.
- Hammer, D.A.,1989, Constructed Wetlands for
Wastewater Treatment Municipal, Industrial and
Agricultural, ed. Lewis Publishers, Inc. Chelsea,
Michigan. - Payton, James, 1996, Constructed Wetlands,
http//www.eng.auburn.edu/paytojd/wetland.html. - Typha latifolia Common Cattail
http//www.rook.org/earl/bwca/nature/aquatics/typh
alat.html. 2002. - www.missouri.edu/rjse10/home.htm Archaeometry
Laboratory - University of Missouri Research Reactor. 2002
37Brownfields
38Definition
- With certain legal exclusions and additions, the
term brownfield site' means real property, the
expansion, redevelopment, or reuse of which may
be complicated by the presence or potential
presence of a hazardous substance, pollutant, or
contaminant - The Brownfields Site definition is found in
Public Law 107-118 (H.R. 2869) - "Small Business
Liability Relief and Brownfields Revitalization
Act" signed into law January 11, 2002.
39EPA Brownfields Program
- www.epa.gov/brownfields
- Results-oriented program started in 1995
- Brings together states, communities, and
stakeholders in economic redevelopment - Work together to prevent, assess, safely clean up
and sustainably reuse brownfields - 450,000 brownfields in the U.S. industrial
sites, abandoned gas stations, dry cleaners,
commercial operations
40What can Brownfields offer?
- Clean up environmental hazards
- Remove neighborhood eyesores
- Create jobs
- Boost tax revenue
- Provide housing
- General economic health in local communities
41Barriers to Brownfields
- Environmental liability
- Contaminated properties are subject to
environmental regulations and procedures can
lead to construction delays - Pollution concerns
42www.brownfieldnews.com
43Milwaukee, WI
44Approaches for Brownfields
- View contaminated sites as an economic
development issue with an environmental twist - View projects as real-estate deals that further
community development goals - Begin cleanup and reuse with the end in mind
- Understand that regulatory processes need to
dovetail with development time frames
45If contaminatedsites are viewed as only
pollution problems, disconnected from community
revitalization goals and economic development
strategies, then efforts to reuse these sites
will flounder.
www.neiwpcc.org/lustline.htm
46Baltimore, MD
47Chevy Place - Rochester, NY
- Car dealership/repair shop/gas station 1930
1990 - Abandoned USTs
- Total cleanup costs, including remediation
750,000
48Paper Mill Island, Baldwinsville
49NY DEC Brownfields