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EPA/600/R-07/063
June 2007
Environmental Conditions in Northern Gulf of Mexico
Coastal Waters Following Hurricane Katrina
Prepared by
John Macauley, Lisa M Smith, Virginia Engle, and Linda Harwell
U.S. Environmental Protection Agency
Office of Research and Development
National Health and Environmental Effects Research Laboratory
Gulf Ecology Division
Gulf Breeze, Florida
Walter Berry
U.S. Environmental Protection Agency
Office of Research and Development
National Health and Environmental Effects Research Laboratory
Atlantic Ecology Division
Narragansett, Rhode Island
Jeff Hyland1' Michael Fulton1 and Gunnar Lauenstein2
U.S. Department of Commerce
National Atmospheric and Oceanic Administration
National Ocean Service
National Centers for Coastal Ocean Science
1 Charleston, South Carolina
2 Silver Spring, Maryland
Pete Bourgeois and Tom Heitmuller
U.S. Department of the Interior
U.S. Geological Survey
National Wetlands Research Center
Gulf Breeze, Florida
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Notice
Mention of trade names or commercial products does not constitute endorsement or recommendation for use.
Citation Information
The suggested citation for this report is: USEPA 2007. Environmental Conditions in Northern Gulf of Mexico
Coastal Waters Following Hurricane Katrina. EPA/600/R-07/063. U.S. Environmental Protection Agency,
Office of Research and Development, National Health and Environmental Effects Research Laboratory, Gulf
Ecology Division, Gulf Breeze, Florida.
Cover photograph — GOES Project Science Office
77
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Contents
Acronyms v
Acknowledgments vii
Executive Summary ix
1. Introduction 1
2. Methods 1
2.1 Pre- and post-hurricane sampling designs and field collections 1
2.2 Laboratory processing and QA/QC 3
2.3 Data analysis 4
3. Water Quality Results and Discussion 5
3.1 Water Quality Index 5
3.2 Oil and Grease 9
3.3 Metals 9
3.7 Fecal coliforms in the water column 11
4. Sediment Quality Results and Discussion 13
4.1 Contaminants 13
4.2 Tbxicity 13
4.4 Benthic community characteristics and condition 21
4.5 Sediment Clostridiumperfringens 27
5. Summary and Conclusions 29
6. References 31
Appendix 1: Threshold/Guidance Values for Evaluating Water Quality 35
Appendix 2 37
Appendix 2-1: Metal-aluminum regression parameters derived from
EMAP Louisianan and Virginian Provinces (1990-1994) 38
Appendix 2-2a: Metals chemistry data (dry weight) from Mississippi Sound samples 39
Appendix 2-2b: Metals chemistry data (dry weight) from Lake Pontchartrain samples (|ig/g) 40
Appendix 2-3a: Metals data (dry weight) from Mississippi stations (|imoles/g) 41
Appendix 2-3b: Metals data (dry weight) from Lake Pontchartrain stations (|imoles/g) 42
Appendix 2-4: PAH concentrations from the 13 PAHs used in the calculation of ESB_PAH13 43
Appendix 2-5: Equilibrium partitioning derived sediment benchmarks for eight pesticides 44
Appendix 2-6a: Fipronil® data from Mississippi stations 45
Appendix 2-6b: Fipronil® data from Lake Pontchartrain stations 46
Appendix 3 47
Appendix 3-1: Summary of benthic variables by station in Mississippi Sound and Lake Borgne before
(n= 172) and after (n=30) Hurricane Katrina 48
Appendix 3-2: Appendix 3-2: Summary of benthic variables by station in Lake Pontchartrain before
(n=47) and after (n=30) Hurricane Katrina 54
777
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Acronyms
ADEM
AVS
CDF
CPU
DDT
DIN
DIP
DO
ELISA
EMAP
EPA
ERL
ERM
ERM-Q
ESB
FCV
GC/ECD
GC/MS
GPS
ICP/MS
KOW
LP
LUMCON
MDEQ
MS
MPN
NCA
NOAA
CSV
PAH
PBDE
PCB
QAPP
SEM
TOC
TSS
USGS
WQI
Alabama Department of Environmental Management
acid volatile sulfide
cumulative distribution function
colony forming units
p,p'-dichlorodiphenyltrichloroethane
dissolved inorganic nitrogen
dissolved inorganic phosphorus
dissolved oxygen
Enzyme-Linked ImmunoSorbent Assay
Environmental Monitoring and Assessment Program
U.S. Environmental Protection Agency
effects range low
effects range median
effects range median quotient
Equilibrium Partitioning-Derived Sediment Benchmark
final chronic value
gas chromatograhy electron capture detector
gas chromatograhy mass spectrometry
Global Positioning System
inductively coupled plasma mass spectrometry
octanol-water partition coefficient
Lake Pontchartrain
Louisiana University Marine Consortium
Mississippi Department of Environmental Quality
Mississippi Sound
most probable number
National Coastal Assessment
National Oceanic and Atmospheric Administration
Ocean Survey Vessel
polyaromatic hydrocarbon
polybrominated dephenylether
polychlorinated biphenyl
Quality Assurance Project Plan
simultaneously extracted metals
total organic carbon
total suspended solids
U.S. Geological Survey
Water Quality Index
iv
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Acknowledgments
This report entitled Environmental Conditions in Northern Gulf of Mexico Coastal Waters Following Hurricane
Katrina was prepared by the U.S. Environmental Protection Agency (EPA), Office of Water (OW) Office of
Research and Development (ORD). The content of this report was contributed by EPA, the National Oceanic
and Atmospheric Administration (NOAA) and U.S. Geological Survey (USGS). Special appreciation is
extended to the field crews of the EPA Gulf Ecology Division, NOAA National Centers for Coastal Ocean
Science, USGS National Wetlands Research Center and USGS Water Resources Division - Louisiana Water
Science Center for completing this survey under extreme conditions. We thank all staff state and federal agen-
cies who provided technical reviews and recommendations for the preparation of this document.
EPA / ORD / NHEERL / Gulf Ecology Division:
Alex Almario
Jed Campbell
George Craven
Fred Genthner
Stephanie Friedman
Bob Quarles
Janet Nestl erode
Richard Devereux
DOC / NOAA / NOS / National Centers for Coastal Ocean Science:
Laura Webster
Kimani Kimbrough
Cindy Cooksey
Ed Wirth
Marion Sanders
Katy Chung
J. D. Dubick
DOI / USGS / Water Resources Division - Louisiana Water Science Center:
Charles Demas
Dennis Demchek
Brian Perez
Alabama Department of Environmental Management (ADEM):
Joie Horn
Mississippi Department of Environmental Quality (MDEQ):
David Barnes
Environmental Conditions in Northern Gulf of Mexico Coastal Waters Following Hurricane Katrina
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V7
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Executive Summary
On the morning of August 29, 2005, Hurricane
Katrina struck the coast of Louisiana, between New
Orleans and Biloxi, Mississippi, as a strong category
three hurricane on the Saffir-Simpson scale. The
resulting winds, storm surge, and flooding created
the potential for a tremendous environmental impact
along the northern Gulf of Mexico coast. The U.S.
Environmental Protection Agency (EPA), National
Oceanic and Atmospheric Administration (NOAA),
and U.S. Geological Survey (USGS) conducted a joint
study in October 2005 to assess potential ecological
effects of the hurricane in coastal waters of Lake
Pontchartrain, Louisiana, and Mississippi Sound
from Dauphin Island, Alabama, to the western side
of Lake Borgne, Lousiana. Post-hurricane conditions
were compared to pre-hurricane conditions using data
collected from the same areas in 2000 to 2004 with
similar indicators and protocols.
Monitoring surveys were conducted at 30 stations in
Lake Pontchartrain from October 11-14, 2005, using
small trailerable boats and at 30 stations in Mississippi
Sound from October 9-15, 2005, using small boats
staged from EPAs OSV Bold'm Gulfport, Mississippi.
A major focus of these surveys was on the collection
and analysis of water and sediment samples using
standard protocols and core indicators applied in
EPAs Environmental Monitoring and Assessment
Program (EMAP) and National Coastal Assessment
(NCA) programs. Water analyses included nutrients,
chlorophyll a, total suspended solids, carbon, water-
borne pathogens (fecal coliforms and enterococci),
and chemical contaminants (organochlorine pesticides,
PCBs, PAHs, oil and grease, and metals). Sediment
was collected from multiple grabs at each site,
combined into single station composites, and then
sub-sampled for toxicity testing and the analysis of
chemical contaminants, microbial/pathogenic indica-
tors, TOC, and grain size. One additional sediment
grab (0.04 m2) was collected at each site for analysis
of benthic macroinfauna (> 0.5 mm). These data were
compared to similar data collected prior to the storm
and to environmental evaluation thresholds available
in the literature.
Dissolved oxygen increased after the hurricane in
both Lake Pontchartrain and Mississippi Sound/Lake
Borgne due most likely to mixing of the water column
from wind and tidal action. Storm-related changes in
bottom-water salinity also occurred in both systems
though with contrasting patterns. The salinity change
was particularly pronounced in Lake Pontchartrain,
which shifted from a predominantly oligohaline
system prior to the hurricane to predominantly
mesohaline after, due possibly to storm surge and
the intrusion of more saline water from Lake Borgne
and Mississippi Sound. Portions of Mississippi
Sound, particularly on the west side, became slightly
less saline after the hurricane, due most likely to
dilution from runoff and mixing of water from Lake
Pontchartrain and Lake Borgne.
Total suspended solids (TSS) in the water column
increased in Lake Pontchartrain and decreased in
Mississippi Sound following the hurricane. As a
result, water clarity decreased in Lake Pontchartrain
and increased in Mississippi Sound. Average
concentrations of chlorophyll a (Chla) in the water
column increased in Mississippi Sound following the
hurricane, while there was little storm-related change
in Lake Pontchartrain. Overall water quality following
Hurricane Katrina, as assessed using the five core
water-quality parameters (DO, Chla, DIN, DIP, and
water clarity), did not differ significantly from previ-
ous years based on five years of probabilistic survey
data.
There were no significant elevations of organic or
inorganic chemical contaminants in the water column
and indicators of pathogen contamination were
extremely low as well. There also were no exceed-
ances of Effects Range Median (ERM) sediment
quality guideline values for chemical contaminants
(Long et al., 1995) in any of the sediment samples
collected from Lake Pontchartrain or Mississippi
Sound following the hurricane. While lower-threshold
Effects Range Low (ERL) values were exceeded for
arsenic, cadmium, and nickel at several stations in
both survey areas, similar levels of contamination
have occurred prior to the hurricane, indicating
very little change in the concentrations and type of
contaminants due to the hurricane. The insecticide
Fipronil® was detected in post-hurricane sediments
from both Lake Pontchartrain and Mississippi Sound.
However, no sediment quality guideline value or
pre-hurricane data on Fipronil® concentrations are
available for comparison. When concentrations of
chemical contaminants were normalized to aluminum
concentrations, it was determined that there was little
risk to benthic fauna from metals, PAH's, and most
vii
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pesticides with the exception of Fipronil®. However,
there are insufficient data on the toxicity of Fipronil®
to assess the biological significance of its low, yet
detectable levels.
There were notable changes in several benthic
community characteristics between the pre- and post-
hurricane periods that are suggestive of storm-related
effects in both Lake Pontchartrain and the more open
waters of Mississippi Sound. These included shifts
in the composition and ranking of dominant taxa and
reductions in number of taxa, FT diversity, and total
faunal abundance. Such changes did not appear to be
linked to chemical contamination, organic enrichment
of sediments, or hypoxia at least as major causes.
Storm-related changes in salinity were a more likely
cause of the observed benthic changes in both systems.
Storm-induced scouring of sediments could have
contributed to these effects as well.
The results from this study represent a snapshot
of ecological condition in coastal waters of Lake
Pontchartrain and Lake Borgne-Mississippi Sound
two months after the passing of Hurricane Katrina.
The comparison of ecological indicators before and
after the hurricane suggests considerable stability of
these systems with respect to short-term ecological
impacts. While some storm-related changes could be
detected (e.g., effects on benthic communities associ-
ated with shifts in salinity), there was no consistent
evidence to suggest widespread ecological damage.
These coastal ecosystems in general appeared to have
absorbed much of the physical impact of the storm
along with any anthropogenic materials that may have
been mobilized by the floodwater and storm surge.
Yet, it must be noted that the present study, conducted
shortly after the hurricane, was not designed to assess
potential long-term chronic environmental effects.
Follow-up studies are recommended to evaluate such
impacts.
viii Environmental Conditions in Northern Gulf of Mexico Coastal Waters Following Hurricane Katrina
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1. Introduction
On the morning of August 29, 2005, Hurricane Katrina
struck the coast of Louisiana between New Orleans
and Biloxi, Mississippi, as a strong category three
hurricane on the Saffir-Simpson scale, with sustained
winds of 125 mph and central pressure of 920 mb
(NOAA/NCDC 2005). Within 24 hours prior to
landfall, Katrina was a category five hurricane reach-
ing maximum sustainable winds of 170 mph. Rainfall
accumulations were in excess of 8-10 inches along
much of the coast, and there was coastal storm-surge
flooding of 20-30 feet above normal tidal levels. The
massive winds and flooding resulted in enormous
losses of human lives and property.
The U.S. Environmental Protection Agency (EPA),
National Oceanic and Atmospheric Administration
(NOAA), U.S. Geological Survey (USGS), and U.S.
Food and Drug Administration (FDA) have been
engaged in a comprehensive interagency effort to
assess human-health and environmental impacts
of Hurricane Katrina in affected coastal waters of
Louisiana, Mississippi, Alabama, and northern Gulf of
Mexico. By integrating response activities conducted
in estuarine and near-coastal waters aboard EPA's
OSV Bold and the NOAA Ship NANCY FOSTER,
with numerous field activities in shallower inland and
wetland environments, this combined effort has sought
to characterize the magnitude and extent of coastal
contamination and associated human-health and
ecological effects resulting from this unprecedented
storm. The present report provides a summary of
initial results of one component of this overall coor-
dinated effort, i.e., an assessment of environmental
condition of Lake Pontchartrain, Louisiana, sub-tidal
waters and the more open near-coastal waters of
Mississippi Sound from Dauphin Island, Alabama, to
the western side of Lake Borgne, Louisiana (Fig. 1-1).
Monitoring surveys were conducted in Lake
Pontchartrain from October 11-14, 2005, using small
trailerable boats and in Mississippi Sound from
October 9-15, 2005, using small boats staged from
the OSV Bold in Gulf Port, Mississippi. Amajor
focus of these surveys was on the collection and
analysis of water and sediment samples using standard
protocols and core indicators developed by EPA's
Environmental Monitoring and Assessment Program
(EMAP) and National Coastal Assessment (NCA)
programs (USEPA 2002, 1999), prior NCA assess-
ments conducted in the same area from 2000 to 2004.
As in prior NCA assessments, a probability-based
sampling design consisting of 30 randomly selected
sites in each of the two post-hurricane survey areas
was used to support statistical estimates of ecological
condition relative to the various indicators measured.
These included standard NCA ecological indicators of
sediment quality, water quality, and benthic condition.
Additional water and sediment samples were collected
and analyzed for microbial indicators of human-health
risks and newly emerging contaminants of concern.
Our goal was to provide a comprehensive and scien-
tifically sound assessment of initial human-health risks
and environmental impacts of Hurricane Katrina in the
affected waters and to establish a useful benchmark
for determining how these conditions may be chang-
ing with time. Results were made available to local,
state, regional and federal decision-makers to support
related environmental and public-health decisions,
recovery, and restoration efforts.
2. Methods
2.1 Pre- and post-hurricane sampling designs
and field collections
Table 2-1 provides a summary of the number of
stations included in both the pre- and post-hurricane
surveys of Mississippi Sound (MS) and Lake
Pontchartrain (LP) survey areas. Locations of the 60
post-hurricane stations, including 30 each in Lake
Pontchartrain and Mississippi Sound, are presented in
Fig. 1-lb. All stations were selected using a random
probability-based survey design. This approach is a
powerful assessment tool for making unbiased statisti-
cal estimates of the spatial extent of a study area that
is in degraded condition, based on the comparison of
measured ecological indicators to desired management
thresholds. A similar approach has been applied
throughout EPA's EMAP and NCA programs (USEPA
2002, 1999). Methods for estimating the proportion
of area of each system meeting certain criteria, and its
associated variance, are based on published formulae
for stratified random sampling designs (Cochran
1977).
The survey design required that various measurements
and samples be obtained at each of the sampling
stations during the post-hurricane surveys in Lake
Environmental Conditions in Northern Gulf of Mexico Coastal Waters Following Hurricane Katrina
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(A)
Louisiana
/Lake Pontchartrain
V
Gulf of Mexico
(B)
/•
Louisiana
Alabama
Gulf of Mexico
Fig. 1-1. Study area and sampling locations in Mississippi Sound and Lake Pontchartrain during (a) pre-Hurricane Katrina
(2000-2003) and (b) post-Hurricane Katrina (October 2005) surveys.
Environmental Conditions in Northern Gulf of Mexico Coastal Waters Following Hurricane Katrina
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Sampling
Period
Pre-Hurricane
2000
2001
2002
2003
2004
Total
Post-Hurricane
(Oct 05)
MS
29
36
34
37
36
172
30
LP
6
10
10
13
10
49
30
Table 2-1. Summary of number of stations included in
pre- and post-hurricane surveys of Mississippi Sound (MS)
and Lake Pontchartrain (LP) survey areas.
Pontchartrain and Mississippi Sound (October 2005).
These included sediment samples for the analysis of
chemical contaminants (DDT and other conventional
chlorinated pesticides, PCBs, PAHs, metals), micro-
bial/pathogenic indicators (Clostridium perfringens),
grain size and organic carbon content (TOC), condi-
tion of resident benthic fauna, and sediment toxicity
(Microtox®) as measures of contaminant exposure
and biological effect. Hydrographic parameters (DO,
salinity, temperature, pH, depth, water clarity), were
measured, and water samples were collected and
analyzed subsequently for nutrients (total N and P,
dissolved nitrate, nitrite, orthophosphate, and ammo-
nium), chlorophyll a, total suspended solids, dissolved
organic carbon, chemical contaminants (conventional
organochlorine pesticides, PCBs, PAHs, oil and
grease, metals), and microbial/pathogenic indicators
(Enterococcus, fecal coliforms, and viral indicators).
Additional contaminants of concern were analyzed,
including atrazine in water, flame retardants (e.g.,
PBDEs) in sediments, and Fipronil® in sediments, as
their potential human-health and ecological impacts
have only recently become apparent in coastal and
marine environments.
All sites were sampled in accordance with the stan-
dard procedures in the NCA Field Methods Manual
(USEPA 200la) and in accordance with the NCA
Quality Assurance Project Plan (USEPA 200Ib) where
applicable. Each station was located using the Global
Position System (GPS). Sediments were collected
using a 20 cm2 Young-modified Van Veen benthic grab.
Grab samples were collected to a maximum depth of 10
cm and rejected if < 5 cm or if there was other evidence
of sampling disturbance (e.g., major slumping, debris
caught in jaws). Sediment for toxicity testing and the
analysis of chemical contaminants, microbial/patho-
genic indicators, TOC, and grain size was composited
from multiple grab samples at each station until there
was sufficient volume for the analyses. The entire
contents of one additional grab were sieved (0.5 mm)
and the material remaining on the screen fixed in 10%
buffered formalin with rose bengal for benthic infau-
nal community analysis. Nutrients and chlorophyll a
samples were collected 0.5 m below the surface and
0.5 m above the bottom using a Beta Plus® sampler.
A Hydrolab® H20 sonde was used to measure salin-
ity, temperature, pH, and dissolved oxygen at 1.0 m
intervals from surface to bottom at each station. Secchi
depth was also measured. Individual water samples
were collected for organic and inorganic contaminants,
oil and grease, and total suspended solids at 0.5 m
below the surface and 0.5m above the bottom. Separate
surface water samples were collected in sterile bottles
for measurement of microbial and pathogen indicators.
2.2 Laboratory processing and QA/QC
All sample analyses were performed in accordance
with the NCA Quality Assurance Project Plan (QAPP)
(USEPA 2001) unless otherwise stated. Sample
analyses were performed by a contract laboratory or
the NOAA - NCCOS laboratory in Charleston, South
Carolina.
Sediment samples were analyzed for pesticides, PAHs,
and PCBs using GC/ECD with dual-column output or
GC/MS methodologies. Analysis for metals, with the
exception of mercury, was performed using an ICP/
MS. Mercury was analyzed with a mercury analyzer
using cold vapor methodology. Determination of
"Total Organic Carbon" concentration in the sediment
was done using a C:H:N analyzer. Benthic infaunal
samples were sent to a contract laboratory and
transferred from formalin to 70% ethanol. Animals
were sorted from the sample debris under a dissecting
microscope and identified to the lowest practical taxon
(usually species). The toxicity potential of sediment
samples from Mississippi Sound was evaluated using
the Microtox® assay. This assay provides a measure
of toxicity potential based on the attenuation of light
production by the photoluminescent bacterium, Vibrio
fischeri. Sediments were classified as either toxic or
non-toxic using criteria developed by Ringwood and
Keppler(1998).
Environmental Conditions in Northern Gulf of Mexico Coastal Waters Following Hurricane Katrina
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The concentrations of dissolved nitrate, nitrite,
orthophosphate, and ammonium were measured
using standard wet chemistry methodologies on an
autoanalyzer. Total nitrogen and total phosphorus
concentrations were determined using a persulfate
digestion method, followed by wet chemistry analyses.
Samples for chlorophyll a and total suspended solids
were filtered in the field, with the filters returned to
the laboratory for final processing. Chlorophyll a was
extracted using 100% methanol and the concentration
determined using fluorometric methods. Filters for
total suspended solids were dried at 110° C, weighed,
and the concentration calculated per liter of water
filtered.
Water samples for contaminant analyses of pesticides
and PAH's were extracted and concentrations deter-
mined using GC/MS methodologies. Metals analyses,
with the exception of mercury, were performed using
an ICP/MS. Mercury was analyzed using a mercury
analyzer using cold vapor methodology. Water
samples were analyzed for oil and grease using a
gravimetric methodology in accordance with EPA
Method 1664. A commercially available ELISAkit
was used to estimate atrazine concentrations in water
samples from Mississippi Sound.
Indicators of fecal contamination, enterococci and
fecal coliform bacteria, were enumerated to assess
potential human-health risks of pathogen exposure
in the Gulf of Mexico. Both Mussel Watch and Joint
Inter-Agency assessments used membrane filtration
and m FC agar to enumerate fecal coliforms (APHA,
1998). Sample volumes ranging from 0.1-100 ml of
water were filtered through 0.45 jim nitrocellulose
membranes and the membrane placed on appropriate
media and incubated at 44.5 ± 0.5° C for 24 ± 2 hours.
Indicative blue fecal coliform colonies were counted
and the density of fecal coliforms colony forming
units (CPUs) per 100 ml of sample was calculated.
The Enterolert system was used to enumerate entero-
cocci (IDEXX, 2004) in samples from Mississippi
Sound. Ten ml of the seawater sample were diluted
with 90 ml of sterile water and pre-measured and
prepackaged media was added to the sample. The
mixture was then added to the specialized plastic tray
containing one large well and 50 small ones. The tray
was sealed and incubated at 41 ± 0.5° C for 24 hours.
Wells positive for growth fluoresce under ultraviolet
light. The numbers of positive wells were counted,
and a Most Probable Number (MPN) table was used to
estimate the MPN of enterococci per 100 ml of water
sample.
Membrane filtration with m Enterococcus agar was
used to enumerate enterococci (IDEXX, 2004) in
samples from Lake Pontchartrain (APHA, 1998).
This method involved filtering 0.1, 1, 10, 50 and
100 ml of sample water through a 0.45 jim nitrocel-
lulose membrane. Each membrane was placed on
m Enterococcus agar and incubated for 48 hours at
35 ± 0.5° C. Pink and red enterococci colonies were
counted and the number of enterococci CFU/100 ml of
sample was calculated.
Clostridium perfringens spores were enumerated
by passing an appropriate volume of water sample
through a membrane filter (0.45 um) that retains the
bacteria present in the sample. The membrane filter
was placed on Perfringens agar (OSCP) and incubated
anaerobically for 24 hours at 37° C. To enhance
color formation the filter was often overlayed with an
additional coating of media. Perfringens agar (OPSP,
Oxoid) is based on the formulation of Handford.
The medium utilizes sulphadiazine (100 ug/ml),
oleandomycin phosphate (0.5 ug/ml) and polymyxin B
sulphate (10 lU/ml) to give a high degree of selectivity
and specificity for C. perfringens which produces
black colonies on this medium. Because of the
selectivity of the mCP medium, a presumptive count is
normally reported for routine monitoring purposes.
2.3 Data analysis
The cumulative distribution function (CDF) analysis
(Horvitz-Thompson Normal approximation) was used
to describe the distribution and confidence intervals
of water quality indicator values for both the pre-
Katrina and post-Katrina survey areas. Each indicator
measure was compared to water quality criteria or
guidance values to estimate condition (good, fair,
poor) at each site. The CDF was used to estimate the
areal extent of condition for each indicator and for the
water quality index (WQI) (Diaz-Ramos et al., 1996).
Water quality indicators were evaluated using the
criteria and guidance values in Appendix 1. The WQI
was calculated from the scores of the following indica-
tors: DO, DIN, DIP, Chla, and water clarity. The
WQI was based on the number of indicators scored as
Environmental Conditions in Northern Gulf of Mexico Coastal Waters Following Hurricane Katrina
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poor. If >2 indicators were poor, then WQI= poor; if
1 indicator scored poor or > 3 scored fair, WQI= fair,
else WQI=good.
A "Sediment Quality Index" was developed in a
similar manner using the following variables: sedi-
ment toxicity, sediment total organic carbon content,
and concentrations of contaminants above the Effects
Range Low (ERL) or Effects Range Median (ERM)
values from Long et al., (1995). ERL values are
lower-threshold concentrations below which adverse
biological effects are expected to occur < 10% of
the time, and the ERM values are higher-threshold
concentrations above which adverse effects are
expected to occur 50% or more of the time.
Mean ERM-Quotients (ERM-Qs), which are the
means of individual contaminant concentrations in a
sample relative to corresponding ERM values, were
used to quantify potentially harmful mixtures of
multiple contaminants present at varying concentra-
tions (Hyland et al., 2003). Samples with mean
ERM-Qs > 0.062 were regarded as having a high
level of chemical contamination associated with a
corresponding high risk of impaired benthic condition.
Benthic species occurrence data were used to
compute density (m~2) of total fauna (all species
combined), densities of numerically dominant species
(m~2), numbers of species, H' diversity (Shannon and
Weaver 1949) derived with base-2 logarithms, and a
multi-metric index of benthic condition (BI, Engle et
al., 1994; Engle and Summers 1998,1999). Scoring
criteria used to classify samples as healthy or impaired
with respect to the latter benthic index were based on
the following breakpoints as applied in refinements
to the index by Engle and Summers (1998, 1999):
> 5 healthy, < 3 degraded, and 3-5 intermediate).
Differences in the above benthic variables before vs.
after the hurricane were examined using a combina-
tion of statistical (Mests) and graphical comparisons
including Cumulative Distribution Functions (CDFs).
3. Water Quality Results
and Discussion
3.1 Water Quality Index
Post-Katrina water quality data were analyzed to
determine the areal extent of condition for water
clarity, dissolved oxygen, chlorophyll a, nitrogen, and
phosphorus. These data were compared to previous
NCA survey data collected from 2000 - 2004. Each
water quality parameter was compared pre- and post-
storm. After that, the water quality index was calcu-
lated to compare overall water quality before and after
the storm. This index consists of five components:
water clarity, dissolved oxygen, chlorophyll a, nitro-
gen, and phosphorus. Each of the components was
assigned a rating of good, fair, or poor. The ratings
were then combined to rank each of the sites. The
areal extent of the ratings was assessed based on the
rankings. Concentrations of water-borne contaminants
were also measured and compared to existing water
quality criteria. Water samples for the analyses of
contaminants (oil and grease, metals, pesticides, and
PAHs) were only collected after Hurricane Katrina.
From 2000-2004, the percent area with bottom DO >
5 mg/L averaged 64% while the percent area hypoxic
(DO < 2 mg/L) averaged 3%. In 2004, the year prior
to Hurricane Katrina, approximately 56% of the area
surveyed from Lake Borgne-Mississippi Sound had
bottom DO concentrations >5 mg/L (Fig. 3-1). Forty-
one percent of the area was scored as fair with bottom
DO concentrations between 2 and 5 mg/L and <3%
of the area had bottom DO concentrations < 2 mg/L.
Following the storm, the area with bottom DO concen-
trations >5 mg/L increased to 96% and approximately
4% of the area had bottom DO concentrations between
2 and 5 mg/L. No bottom DO concentrations < 2 mg/
L were observed after Hurricane Katrina. Increases in
bottom DO concentrations may be attributed to mixing
of the water column from wind and tidal action.
From 2000-2004, an average of 60% of the area of
Lake Pontchartrain had more bottom DO concentra-
tions > 5 mg/L and 15% of the area was hypoxic. After
Hurricane Katrina an estimated 97% of the area of
Lake Pontchartrain had bottom DO concentrations > 5
mg/L, up from 80% in 2004 (Fig. 3.1). Ten percent of
the area of Lake Pontchartrain had bottom DO concen-
trations < 2 mg/L in 2004. Bottom DO concentrations
< 2 mg/L were not observed during the post-Katrina
survey in Lake Pontchartrain. Again, physical forces
are mostly likely the driving factors resulting in
increased DO concentrations in Lake Pontchartrain
after the storm.
Prior to Hurricane Katrina (2004), 12% of the
Mississippi Sound survey area was oligohaline, 51%
mesohaline, and 37% polyhaline based on average
Environmental Conditions in Northern Gulf of Mexico Coastal Waters Following Hurricane Katrina
-------
surface to bottom salinities (Fig. 3-2). Following the
hurricane, the oligohaline areas of the Mississippi
Sound survey area were eliminated by storm surge
of high salinity Gulf of Mexico water. The resulting
salinity regime within the survey area was 50% of the
area being characterized as mesohaline and 50% poly-
haline. For 2000-2004, the average areal distribution
of salinity for the survey area was 35% oligohaline,
53% mesohaline, 32% polyhaline and 3% marine.
Mississippi Sound, particularly on the western side,
became slightly less saline after the hurricane, due
most likely to dilution from runoff and mixing of
water from Lake Pontchartrain and Lake Borgne (see
discussion below in the benthic Section 4.4).
The areal percentage of Lake Pontchartrain character-
ized as oligohaline steadily increased from 2000-2004
based on average surface to bottom salinity (Fig.
3.2). In 2004, approximately 90% of the area was
oligohaline and 10% mesohaline. Average water-
column salinities in Lake Pontchartrain were slightly
higher following Hurricane Katrina, due most likely
to the storm surge and intrusion of more saline water
from Lake Borgne and Mississippi Sound. The salinity
regime shifted to a more saline system with only 3%
DO
(Posl-Kalrina) 2005
20«
2003
2002
2001
2000
0
(Posl-Kafrina) 2005
2004
2003
2002
2001
2000
L.ike Bof(jne-Mississi|)|]i Sound
' =•
| |
1 1
ft 20% 40% E0% 80% 100% DFair
• Poor
• Missing
L*e Pimtt h.ati ,111
1 1
1 1
1 1 1
1 1
1 1 1
0% 10% 20% 30% 40* 50% 60* 70% 80% 90* 100%
Percent ftrss
of the surveyed area characterized as oligohaline and
97% of the area as mesohaline. Such rapid changes in
salinity stresses benthic and pelagic communities and
negatively affects submerged aquatic vegetation.
Total suspended solids (TSS) concentrations
increased in Lake Pontchartrain post-Katrina. The
area exhibiting > 20 mg/L TSS increased from 0
to 17%. However, the amount of area with TSS
concentrations <10 mg/L did not change (Fig. 3-3).
Lake Pontchartrain is a shallow system and would
have been susceptible to re-suspension of bottom
sediments due to wind and wave action from the
storm. Increased runoff into Lake Pontchartrain may
have also been a factor contributing to the increased
TSS concentrations. Although the area of Lake
Pontchartrain with TSS concentrations > 20 mg/L
increased from 2004, this area (17%) was similar to
the average area observed to have concentrations > 20
mg/L (19%) during the survey period from 2000-2004.
Conversely, the area in Mississippi Sound with TSS
concentrations > 20 mg/L following Hurricane Katrina
decreased from that observed in 2004 (Fig. 3-3). The
open exchange of the Mississippi Sound survey area
with the Gulf of Mexico may have allowed for purging
Salinity
(RDst-Katrha) 2005
2004
2003
2002
2001
2000
0
(Rjst-Katrha) 2005
2004
2003
2002
2001
2000
Liike Boip
Sound
i
|
1
I
I
I
1
1
% 1 0% 20% 30% 40% 50% 60% 70% 80% 90% 1 00%
n Oligohaline
D Mesohaline
DPolyhaline
• Marine
Lake Ponlchartrain
1
|
i
i i
0% 1 0% 20% 30% 40% 50% 60% 70% 60% 90% 100%
Fig. 3-1. Area of Lake Borgne-Mississippi Sound and Lake
Pontchartrain exhibiting good-fair-poor bottom dissolved
oxygen concentrations pre- and post-Hurricane Katrina
(threshold values are listed in Appendix 1.0).
Fig. 3-2. Area of Lake Borgne-Mississippi Sound and Lake
Pontchartrain exhibiting oligohaline-mesohaline-polyhaline
conditions pre- and post-Hurricane Katrina.
Environmental Conditions in Northern Gulf of Mexico Coastal Waters Following Hurricane Katrina
-------
of the system. The area with TSS concentrations > 20
mg/L following Katrina was nearly 4 times less than
the average area with these concentrations estimated
from 2000-2004 survey data.
Water clarity decreased in Lake Pontchartrain and
increased in Mississippi Sound following Katrina
(Fig. 3-4). The areal extent of good water clarity
in Lake Pontchartrain decreased from 90% in 2004
to 43% post-Katrina and increased from 16% to
33% in Mississippi Sound. Poor water clarity was
not observed in Lake Pontchartrain surveys prior
to Katrina. The area with poor water clarity in
the Mississippi Sound survey area decreased from
46% to 10%. Increases in TSS concentrations may
have contributed to decreased water clarity in Lake
Pontchartrain following Hurricane Katrina. The area
of Lake Pontchartrain with good water clarity was
approximately half the average area estimated to have
good water clarity between the years 2000-2004. The
biggest change in water clarity in Lake Pontchartrain
was from good to fair after the hurricane. The percent
area of the Mississippi Sound survey area with good
water clarity post-Katrina was less than the 2000-2004
TSS
: .1 • • -ii :, 2005
2C04
Lake Borgne-MiMlsaptjl Sound
3:02
3:01
3:013
0% 10* sow 30% -40% 50% eo<* TO% so% sot, torn
D--10raj.t
• 10.20 nrgA.
Lake Pontchartrain
0% 1OT4 K>% 30% 40* 50* 60% 70% 80% 90* 100%
Fig. 3-3. Area of Lake Borgne-Mississippi Sound and Lake
Pontchartrain exhibiting < 10 mg\L, 10-20 mg\L, and > 20
mg\L of total suspended solids concentrations pre- and
post-Hurricane Katrina.
average (33% vs 48%); however, the percent area with
poor water clarity was lower than the 5-year average
(10%vs26%).
Average concentrations of chlorophyll a (chla) in
the water column increased in the Mississippi Sound
survey area in the month following Katrina. The
biggest difference between 2004 and post-Katrina
was in the area with chla concentrations between <5
ug/L and 5-20 ug/L. Three percent of the area had
chla concentrations >20 ug/L compared to none in
2004 (Fig. 3-5). Five-year averages of the Mississippi
Sound survey show a combined area of 99% with chla
concentrations < 20 ug/L. In Lake Pontchartrain, the
cumulative distribution of chla concentrations did not
change. However, the area with concentration in the
fair category has increased each year since 2000.
Over the past 5 years, the percentage of the
Mississippi Sound survey area with concentrations
of dissolved inorganic nitrogen (DIN) >0.1 mg/L
has decreased, while dissolved inorganic phosphorus
(DIP) concentrations >0.01 mg/L have increased (Fig.
3-6). Post Hurricane Katrina, the entire Mississippi
Sound survey area had DIN concentrations <0.1 mg/L.
The percent of the Mississippi Sound survey area
Water Cla
(Post-Katrina) 2005
2004
2003
2002
2001
2000
0
(Post-Katrina) 2005
2004
2003
2002
2001
2000
-j. Lake B« g|ne-Mississi|>|)i Sonul
II I
I LT I
• Good
% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100% QFair
• Poor
• Missing
Lifce pHUikl hill Mil
•BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBll
^^1
0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%
Percent £rea
Fig. 3-4. Area of Lake Borgne-Mississippi Sound and Lake
Pontchartrain exhibiting good, fair, and poor water clarity
pre- and post-Hurricane Katrina (threshold values are listed
in Appendix 1.0).
Environmental Conditions in Northern Gulf of Mexico Coastal Waters Following Hurricane Katrina
-------
with DIP concentrations between 0.01 and 0.05 mg/L
increased after the storm compared to the average
area surveyed from 2000-2004; however, percentage
of area with DIP concentrations > 0.05 mg/L was 0%
compared to the 5-year average of 13%. Increased
runoff may have elevated nutrient concentrations in
some portions of the survey area while Gulf waters
may have diluted nutrient concentrations. Excess
nutrients, especially nitrogen are quickly utilized by
phytoplankton in this system and diluted by oligotro-
phic marine waters, (Smith, 2006).
Compared to 2003, Lake Pontchartrain DIN and DIP
concentrations decreased. DIN concentrations < 0.1
mg/L were observed for 97 % of the area after the
hurricane compared to 82% for the average area from
2000-2003. No DIP concentrations > 0.05 mg/L were
observed in Lake Pontchartrain following the storm
compared to the average percent area of 24% observed
from 2000-2003. If excess nutrients were introduced
into Lake Pontchartrain as a result of runoff, they were
mostly likely rapidly utilized.
Overall water quality post-Katrina in the Mississippi
Sound survey area was similar to 2004. Water qual-
ity from an ecological perspective was not severely
altered as assessed using 5 years of probabilistic
survey data. When sampled approximately 6 weeks
after the storm the percent area with good and fair
(Post-Katrina) 2005
2004
2003
>-
2002
2001
2000
0
(Post-Katrina) 2005
2004
2003
OJ
01
>
2002
2001
2000
LAe Boi (jie fvississiwi Sound
• I I
|
|
CHLA
• uood
ft 10% 20% 30% 40% 50% 60% 70% 80% 90% 100% D F ai r
• Poor
• Missing
L ii u-iin
| |
|
| |
I I
I I
I I
0% 10% 20% 30% 40% 50% 60% 70% 30% 90% 100%
Percent Area
Fig. 3-5. Area of Lake Borgne-Mississippi Sound and Lake
Pontchartrain exhibiting good, fair, and poor concentrations
of chlorophyll a, pre- and post-Hurricane Katrina (threshold
values are listed in Appendix 1.0).
A
CPost-Kslrina)2005
2004
2003
2002
2001
2000
0
(Post-Kafrina) 2005
2004
2CICG
2002
2001
2000
0°
B
(Post-Kafrina) 2005
2004
2003
2002
2001
2003
0
(Poit-Ko1rino)2005
2004
2003
2002
2001
2000
0"
Lake Bor M Soiml
1
|
|
1 1 _,.
DIN
• Good
ft 10% 20% 30% 40% 50% 60% 70% 30% 90% 100% nFair
• Poor
• Missing
Lake F'onr- li.iih Hiii
| |
|
I |
t 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%
Percent Ates
Lake Bin |)i SOIIN!
| |
I I
|
I I I
DIP
ft 20% 40% 60% 80% 100% d Fair
• Poor
• Missing
Lt*e Pontch-irti oil
^H |
| |
i
| |
t 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%
Percent Afes
Fig. 3-6. Area of Lake Borgne-Mississippi Sound and Lake
Pontchartrain exhibiting good, fair, and poor concentrations
of dissolved inorganic nitrogen (a) and dissolved inorganic
phosphorus (b) pre- and post-Hurricane Katrina (threshold
values are listed in Appendix 1.0).
8
Environmental Conditions in Northern Gulf of Mexico Coastal Waters Following Hurricane Katrina
-------
water quality was 13% and 87% respectively (Fig.
3-7). The 5 year pre-storm areal average for overall
water quality was 32% and 64%, respectively, and
4% for good, fair and poor water quality, respectively.
In Lake Pontchartrain, a similar trend was observed.
The average areal percentages for water quality from
2000-2003 were 23% good, 62% fair and 15% poor.
Following Hurricane Katrina, poor water quality was
not observed in Lake Pontchartrain. Thirteen percent
of the area had good water quality, and 87% had fair
water quality.
L.ike Ba(jne-Mississi|>i» Soind
(Post-Katrina) 2005
2004
20i:e
2UIJ2
2IJL1
20CO
'Water
1 Quality
n% 10% 20% 111% 40% 50%, 60% 70'
L.ike Poiitcluiiti
i •Good
100% QFair
• Poor
• Missing
(Post-Katrina) 2005
2004
2003
2002
2001
2000
10% 20% 30% 40% 50% 60% 70% 80% 90% 100%
Percent ^rea
Fig. 3-7. Area of Lake Borgne-Mississippi Sound and Lake
Pontchartrain exhibiting good, fair and poor water quality
pre- and post-Hurricane Katrina (threshold values are listed
in Appendix 1.0).
3.2 Oil and Crease
Oil and grease results for Lake Borgne-Mississippi
Sound and Lake Pontchartrain are presented in Fig.
3-8. No samples collected from the Lake Borgne-
Mississippi Sound survey area exceeded the 10
mg/L concentration listed for effluent of permitted
outfalls in Mississippi surface waters. The majority
(63%) of the area had oil and grease concentrations
< 5 mg/L. Concentrations between 5.1 and 10.0
mg/L were measured for 37% of the surveyed area.
Approximately 90% of the area surveyed in Lake
Pontchartrain had concentrations of oil and grease
between 5.1 and 10.0 mg/L. Oil and grease concentra-
tion at one site in Lake Pontchartrain exceeded 10
mg/L and 6% of the area had oil and grease concentra-
tions < 5 mg/L.
90% -
80% -
70% -
60% -
50% -
40% -
30% -
20% -
10% -
Oil
&
Grease
• >1D mg/L
n5.1-10mg/L
n 5 m g/L
Lake Pontchartrain Mississippi Sound
Fig 3-8. Area of Lake Borgne-Mississippi Sound and
Lake Pontchartrain exhibiting 5 mg\L, 5.1-10 mg\L, and
> 10 mg\L of dissolved oil & grease concentrations post-
Hurricane Katrina.
3.3 Metals
Concentrations of metals detected in water samples
collected from Lake Borgne-Mississippi Sound and
Lake Pontchartrain are presented in Table 3-1. No
metals measured exceeded EPA's acute criteria for the
protection of aquatic life in marine waters; however,
chronic exposure criteria were exceeded for copper at
one station, for lead at a second station and for both at
a third station in Mississippi Sound (USEPA2002).
3.4 Pesticides and PAHs
All concentrations measured in water samples
collected from Lake Pontchartrain and Lake Borgne-
Mississppi Sound survey areas were below detection
limits for both pesticides and PAHs.
3.5 Atrazine
Atrazine was detected in water samples from 5
of the 28 Mississippi Sound sampling stations
(Table 3-2). Concentrations ranged from 0.10-0.18
ug/L. Concentrations at all sites were well below the
currently proposed saltwater water quality criterion of
17 ug/L.
Environmental Conditions in Northern Gulf of Mexico Coastal Waters Following Hurricane Katrina
-------
Analyte
Aluminum
Arsenic
Cadmium
Chromium
Copper
Lead
Mercury
Nickel
Selenium
Silver
Zinc
Lake Pontchartrain
(ppb)
40.06-2106.4
0.345-0.777
0.018 - 0.042
0.142-0.763
0.954-2.15
0.049 - 0.724
0.001 - 0.003
0.878 - 5.55
0.121 -0.237
0 - 0.041
0.804 - 39.5
Lake Borgne-
MS Sound (ppb)
85.06 - 1776.8
0.49- 1.11
0.016-0.213
0.212-0.75
0.808 - 5.43
0.109- 10.6
0.001 - 0.273
0.618-3.18
0.076 - 0.297
0.006 - 0.022
0.781 - 13.7
Acute WQC
Value (ppb)
-
69
40
-
4.8
210
1.8
74
290
1.9
90
Chronic WQC
Value (ppb)
-
36
8.8
-
3.1
8.1
0.94
8.2
71
-
81
Table 3-1. Concentrations of metals in water samples collected from Lake Borgne-Mississippi Sound and Lake
Pontchartrain following Hurricane Katrina.
Station
KAT-0001
KAT-0002
KAT-0003
KAT-0004
KAT-0005
KAT-0006
KAT-0007
KAT-0008
KAT-0009
KAT-0010
KAT-0011
KAT-0012
KAT-0013
KAT-0014
KAT-0015
KAT-0016
KAT-0017
KAT-0018
KAT-0019
KAT-0020
KAT-0021
KAT-0022
KAT-0025
KAT-0026
KAT-0027
KAT-0028
KAT-0029
KAT-0030
Date Collected
10/11/2005
10/12/2005
10/12/2005
10/10/2005
10/12/2005
10/11/2005
10/11/2005
10/10/2005
10/11/2005
10/10/2005
10/10/2005
10/10/2005
10/12/2005
10/11/2005
10/11/2005
10/11/2005
10/11/2005
10/11/2005
10/12/2005
10/10/2005
10/12/2005
10/11/2005
10/11/2005
10/12/2005
10/10/2005
10/10/2005
10/12/2005
10/12/2005
Atrazine Cone.
nd
nd
0.11
nd
0.11
nd
nd
nd
nd
nd
nd
nd
0.13
nd
nd
nd
nd
nd
nd
nd
nd
nd
nd
nd
nd
nd
0.18
0.10
Table 3-2. Measured concentrations ofatrazine in water
samples collected from Mississippi Sound following
Hurricane Katrina.
10
-------
3.6 Waterborne Pathogens
Clostridiumperfringem in the water column
Clostridiumperfringens is a bacterium found in the
intestinal tract of both humans and animals that enters
the environment through feces. There are no EPA
health-based ambient water quality criteria for C.
perfringens. However, some scientists recommend
using C. perfringens spores as a tracer of fecal pollu-
tion because its presence is a good indicator of recent
or past fecal contamination in water as their spores
survive well beyond the typical life-span of other
fecal bacteria. Results from the post-Katrina survey
in the Lake Borgne-Mississippi Sound survey area
show that concentrations of C. perfringens spores in
the water column were undetectable or low (Fig. 3-9).
Microbial samples are not routinely collected under
the NCA Program; therefore, no pre-storm data are
available to make pre- and post-Katrina comparisons.
Due to sampling constraints, there were no post-storm
samples collected in Lake Pontchartrain for C.
perfringens.
3.7 Fecal coliforms in the water column
Fecal coliform concentrations were compared to
two criteria for shellfish harvesting waters (USEPA
841/R/00/002). The first criterion (14 CFU/100 ml)
is the 30-day median concentration while the second
(43 CFU/100 ml) is the criterion that should not be
exceeded by >10% of samples collected during a
30-day period. None of the samples from either Lake
Pontchartrain or Mississippi Sound exceeded either
of these criteria. The highest concentrations measured
were 12 CFU/100 ml and 3 CFU/100 ml in Lake
Pontchartrain and Mississippi Sound, respectively
(Table 3-3).
3.8 Enterococci in the water column
Ambient Water Quality Criteria for Bacteria (USEPA,
1986) recommends the use of enterococci, a group of
bacteria found in the gastrointestinal tract of warm-
blooded animals, as indicator organisms for measur-
ing fecal contamination of marine waters for the
designated use of swimming as required by the Clean
Water Act (Section 304). EPA recommends that single
sample maximums for bathing waters not exceed 104
CFUs per 100 ml. Bacterial enumeration for entero-
cocci for both the Lake Pontchartrain and Mississippi
Sound survey areas indicate that the number of CFUs
observed did not exceed the 104 CFU/100 guidance
criteria. The maximum number of CFUs/100 ml
observed were 2 and 10 for Lake Pontchartrain and
Mississippi Sound, respectively (Table 3-3).
Lake Borgne-Mississippi Sound
Post-Katrina
Clostridium perfringens(spores per 50 ml)
16.7%
26.7%
56.7%
a < 5 spores
D5-10spores
• 11-20 spores
Fig 3-9. Area of Lake Borgne-Mississippi Sound and Lake
Pontchartrain exhibiting <5 spores/50 ml, 5.0-10 spores/50
ml, and >10 spores/50 ml of Clostridium perfringens
post-Hurricane Katrina.
Environmental Conditions in Northern Gulf of Mexico Coastal Waters Following Hurricane Katrina
11
-------
Lake Borgne-
Mississippi
Sound
KAT-0001
KAT-0002
KAT-0003
KAT-0004
KAT-0005
KAT-0006
KAT-0007
KAT-0008
KAT-0009
KAT-0010
KAT-0011
KAT-0012
KAT-0013
KAT-0014
KAT-0015
KAT-0016
KAT-0017
KAT-0018
KAT-0019
KAT-0020
KAT-0021
KAT-0022
KAT-0023
KAT-0024
KAT-0025
KAT-0026
KAT-0027
KAT-0028
KAT-0029
KAT-0030
*Enterococci
(CPUs/ 100
mL)
<10
<10
<10
10
<10
<10
<10
<10
<10
<10
10
<10
<10
<10
<10
<10
<10
<10
<10
<10
<10
<10
<10
10
<10
<10
<10
<10
<10
<10
Fecal
coliform
(CFUs/1 00 mL)
<1
<1
<1
<1
<1
<1
<1
<1
<1
<1
<1
<1
1
<1
<1
<1
<1
<1
<1
<1
<1
2
<1
<1
<1
3
<1
<1
1
<1
Lake
Pontchartrain
LP-0001
LP-0002
LP-0003
LP-0004
LP-0005
LP-0006
LP-0007
LP-0008
LP-0009
LP-0010
LP-0011
LP-0012
LP-0013
LP-0014
LP-0015
LP-0017
LP-0018
LP-0019
LP-0020
LP-0021
LP-0022
LP-0023
LP-0024
LP-0025
LP-0026
LP-0026
LP-0027
LP-0028
LP-0029
LP-0030
LPALT-0058
**Enterococci
(CPUs/ 100
mL)
<1
<1
<1
<1
<1
<1
<1
<2
<1
<1
<1
<2
<2
<1
1
<1
<1
<1
1
<2
<1
<1
<2
1
<1
<1
<1
<2
<2
<1
<2
Fecal
coliform
(CFUs/100 mL)
<1
<1
<1
<1
1
1
<1
<2
<1
2
1
12
<2
1
<1
2
<1
1
8
2
4
<1
<2
4
<1
<1
3
10
4
<1
6
Methodology = Enterolert ®
** Methodology = Membrane Filtration
Table 3-3. Enterococci and fecal coliform concentrations in surface water samples collected in Lake Borgne-Mississippi
Sound and Lake Pontchartrain following Hurricane Katrina.
12
-------
4. Sediment Quality Results
and Discussion
4.1 Contaminants
Comparisons of sediment-associated contaminants
measured in Lake Pontchartrain and Mississippi
Sound following Hurricane Katrina to sediment
quality guidelines are shown in Tables 4-1 and
4-2, respectively. There were no ERM exceedances
measured at any of the sampling sites in either Lake
Pontchartrain or Mississippi Sound (Tables 4-1 and
4-2). The number of ERL exceedances per site in Lake
Pontchartrain ranged from 0-5 while the number of
ERL exceedances per site in Mississippi Sound sites
ranged from 0-3. There were no ERL exceedances for
any organic contaminants (pesticides, PCBs, PAHs)
at any sites sampled in either Lake Pontchartrain or
Mississippi Sound. The analytes most often detected
at concentrations above the ERL were arsenic,
cadmium, and nickel. Mean ERM quotients in Lake
Pontchartrain sediments ranged from 0.004 to 0.080
and in Mississippi Sound sediments from 0.002 to
0.056.
The insecticide Fipronil® was detected in sediments
from seven sites in Mississippi Sound and two sites
from Lake Pontchartrain following Hurricane Katrina.
In the Mississippi Sound samples, concentrations
ranged from 0.036-1.40 ng/g while concentrations in
the Lake Pontchartrain samples ranged from 0.55-0.96
ng/g.
Flame retardants (PBDEs) were not detected in sedi-
ment samples collected following Hurricane Katrina
from either Mississippi Sound or Lake Pontchartrain.
The mean detection limit was 0.962 ng/g.
The levels of contamination in sediments from Lake
Pontchartrain and Mississippi Sound following
Hurricane Katrina were compared to levels measured
prior to the Hurricane (2000-2003). The number of
ERL exceedances in the 39 sediment samples collected
from Lake Pontchartrain from 2000-2003 ranged
from zero to four. The analytes most often detected at
concentrations above the ERL were arsenic, cadmium,
and nickel (the same as after the hurricane). One sedi-
ment sample collected in 2001 had an ERL exceed-
ance for total DDT. There was one ERM exceedance
for silver in a single sample collected in 2000. Mean
ERM quotients in these Lake Pontchartrain sediments
ranged from 0.006 to 0.092.
The number of ERL exceedances in the 136 sediment
samples collected from Mississippi Sound from
2000-2003 ranged from zero to four. The analytes
most often detected at concentrations above the
ERL were arsenic, nickel, chromium, mercury and
cadmium. There were no ERM exceedances for any of
the sediment samples collected from 2000-2003. Mean
ERM quotients in these Mississippi Sound samples
ranged from 0.000 to 0.083.
In general, comparisons of contaminant levels in
sediments from Lake Pontchartrain and Mississippi
Sound following Hurricane Katrina with levels prior
to the storm indicated little change in the overall
concentrations or distribution of contaminants.
4.2 Toxicity
The potential toxicity of sediment-associated contami-
nants from Mississippi Sound was assessed using the
Microtox® assay (Table 4-3). Sediments were classified
as either toxic or non-toxic using criteria developed
by Ringwood and Keppler (1998). Analyses indicated
that three of the 28 sites sampled in Mississippi Sound
were classified as toxic using this approach. These
sites were KAT-0001, KAT-0017, and KAT-0022. This
observed toxicity did not appear to be related to the
presence of contaminants with existing ERL/ERM
guidelines since there were no ERL exceedances for
any of these sites. One of the sites classified as toxic
(KAT-0001) did have detectable concentrations of the
currently used insecticide Fipronil®, but concentrations
at this site were lower than at several other sites that
were not classified as toxic.
Environmental Conditions in Northern Gulf of Mexico Coastal Waters Following Hurricane Katrina
13
-------
Stat/on
LP-0001
LP-0002
LP-0003
LP-0004
LP-0005
LP-0006
LP-0008
LP-0009
LP-0010
LP-0011
LP-0012
LP-0013
LP-0014
LP-0015
LP-0017
LP-0018
LP-0019
LP-0020
LP-0021
LP-0022
LP-0023
LP-0024
LP-0025
LP-0026
LP-0027
LP-0028
LP-0029
LP-0030
LPALT-0058
Number of ERL
Exceedances
3
0
3
3
2
3
3
3
0
3
3
3
3
0
1
0
3
3
3
0
0
3
4
3
5
2
3
3
2
Number of ERM
Exceedances
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Analytes Exceeding
ERL
As, Cd, Ni
none
As, Cd, Ni
As, Cd, Ni
As, Ni
As, Cd, Ni
As, Cd, Ni
As, Cd, Ni
none
As, Cd, Ni
As, Cd, Ni
As, Cd, Ni
As, Cd, Ni
none
Cd
none
As, Cd, Ni
As, Cd, Ni
As, Cd, Ni
none
none
As, Cd, Ni
As, Cd, Cr, Ni
As, Cd, Ni
As, Cd, Cr, Ni, In
Cd, Ni
As, Cd, Ni
As, Cd, Ni
Cd, Ni
Mean ERMQ.
0.043
0.004
0.052
0.038
0.033
0.040
0.040
0.047
0.031
0.049
0.042
0.060
0.040
0.010
0.037
0.029
0.052
0.042
0.044
0.022
0.016
0.049
0.070
0.041
0.080
0.037
0.062
0.052
0.039
Table 4-1. Contaminants in sediments collected from Lake Pontchartrain following Hurricane Katrina.
14
-------
Stat/on
KAT-0001
KAT-0002
KAT-0003
KAT-0004
KAT-0005
KAT-0006
KAT-0007
KAT-0008
KAT-0009
KAT-0010
KAT-0011
KAT-0012
KAT-0013
KAT-0014
KAT-0015
KAT-0016
KAT-0017
KAT-0018
KAT-0019
KAT-0020
KAT-0021
KAT-0022
KAT-0023
KAT-0024
KAT-0025
KAT-0026
KAT-0027
KAT-0028
KAT-0029
KAT-0030
Number of ERL
Exceedances
3
1
1
3
2
0
0
3
0
0
0
3
0
0
2
0
2
0
0
0
0
0
0
1
1
0
0
1
1
0
Number of ERM
Exceedances
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Analytes
Exceeding ERL
As, Cd, Ni
Cd
Cd
As, Cd, Ni
As, Cd
none
none
As, Cd, Ni
none
none
none
As, Cd, Ni
none
none
Cd, Ni
none
As, Ni
none
none
none
none
none
none
As
As
none
none
As
Cd
none
Mean ERMQ.
0.054
0.031
0.023
0.045
0.035
0.009
0.030
0.056
0.002
0.003
0.025
0.048
0.027
0.012
0.034
0.002
0.045
0.021
0.024
0.017
0.017
0.024
0.028
0.039
0.038
0.030
0.002
0.035
0.029
0.009
Table 4-2. Contaminants in sediments collected from Lake Borgne-Mississippi Sound following Hurricane Katrina.
Environmental Conditions in Northern Gulf of Mexico Coastal Waters Following Hurricane Katrina
15
-------
Stat/on
KAT-0001
KAT-0002
KAT-0003
KAT-0004
KAT-0005
KAT-0006
KAT-0007
KAT-0008
KAT-0009
KAT-0010
KAT-0011
KAT-0012
KAT-0014
KAT-0016
KAT-0017
KAT-0018
KAT-0019
KAT-0020
KAT-0021
KAT-0022
KAT-0023
KAT-0024
KAT-0025
KAT-0026
KAT-0027
KAT-0028
KAT-0029
KAT-0030
Date
Collected
10/11/2005
10/12/2005
10/12/2005
10/10/2005
10/12/2005
10/11/2005
10/11/2005
10/10/2005
10/11/2005
10/10/2005
10/10/2005
10/10/2005
10/11/2005
10/11/2005
10/11/2005
10/11/2005
10/12/2005
10/10/2005
10/12/2005
10/11/2005
10/11/2005
10/10/2005
10/11/2005
10/12/2005
10/10/2005
10/10/2005
10/12/2005
10/12/2005
EC50 (%)
Corrected for
dry weight
0.1221
0.5655
0.2682
1.0149
0.7221
2.3007
2.3643
0.4675
>1 6.8533
>15.4698
2.5104
0.7160
0.7840
>15.3471
0.0179
0.2160
2.8793
0.9035
11.5172
0.1906
0.5944
0.2636
0.3292
3.1035
>15.4451
1.9789
0.3297
1.8528
Toxicity
Yes
No
No
No
No
No
No
No
No
No
No
No
No
No
Yes
No
No
No
No
Yes
No
No
No
No
No
No
No
No
%Sand
4.83
26.01
28.60
18.68
25.94
87.92
nd
3.64
99.56
nd
61.27
12.35
75.89
98.96
0.64
42.34
16.55
55.20
68.17
55.19
55.25
25.51
33.52
44.44
99.12
27.26
43.50
85.86
% Silt/Clay
95.17
73.99
71.40
81.32
74.06
12.08
nd
96.36
0.44
nd
38.73
87.65
24.11
1.04
99.36
57.66
83.45
44.80
31.83
44.81
44.75
74.49
66.48
55.56
0.88
72.74
56.50
14.14
a. Toxic if%EC50 < 0.2 and % Silt/Clay >20 or % EC50 < 0.5 and % Silt/Clay < 20 (Ringwood eta/., 1997)
b. Not determined
Table 4-3. Microtox® Results for sediments collected from Lake Borgne-Mississippi Sound following Hurricane Katrina.
4.3 Sediment Toxicity Prediction normally applied with these approaches were not
available, so worst-case approximations were used in
Aluminum normalization techniques were used to look their place Consequently these approaches cannot be
for metals enrichment in the sediments. Equilibrium used tQ positively predict the toxicity of the samples
partitiomng-derived sediment benchmarks (ESBs) but can be used to mle Qut samples which should not
were also employed to analyze the sediment metals regult in ecological risk and to identify sediments or
and orgamcs data. In some cases, some of the data chemicals which may deserve further investigation.
16
-------
The ESBs used were:
• Equilibrium Partitioning Sediment
Benchmarks for Metals Mixtures (cadmium,
copper, lead, nickel, silver, and zinc) (USEPA,
2005)
• Equilibrium Partitioning Sediment
Benchmarks for PAH Mixtures (USEPA,
2003 a)
• Equilibrium Partitioning Sediment
Benchmarks for individual non-ionic organic
chemicals (for six pesticides) (USEPA, draft)
• Equilibrium Partitioning Sediment
Benchmarks for Dieldrin (USEPA, 2003b)
• Equilibrium Partitioning Sediment
Benchmarks for Endrin (USEPA, 2000c).
4.3.1 Metals: Aluminum Normalization
The degree of metal contamination in the sediments
was assessed by comparing measured concentrations
with estimated background concentrations using
aluminum normalization. The procedure is based on
a simple model in which background sediments are
treated as mixtures of coarse material, low in metal
content (i.e., silica), and metal-rich, fine-grained
aluminosilicate silts and clays. If all the aluminum
in sediment is assumed to come from these alumi-
nosilicates, then metal concentrations in background
sediments should vary linearly with aluminum concen-
tration. In this model, total concentrations of a metal
in sediment which exceed background concentrations
are due to additional, presumably anthropogenic,
components.
An iterative statistical procedure was used to eliminate
sediments with apparent contamination, reducing the
data set to just apparent background sediments. In this
procedure metal concentrations are regressed against
aluminum concentrations and the residuals (the differ-
ences between measured values and those predicted
from the regression) tested for normal distribution.
If the residuals are not normally distributed, samples
with the largest statistically significant residuals
(studentized residual >2) are assumed to be contami-
nated and are eliminated from the data set, and the
regression is repeated until either a normal distribution
is obtained (p=0.01) or there are no more samples with
large, positive residuals. In the latter case, the devia-
tion from a normal distribution is caused by samples
with unusually low metal concentrations relative to
aluminum, but without a reason to eliminate these
samples from the data set, they are included in the
"background" sediments.
This procedure was used to derive metal-aluminum
relationships in EMAP data from the NE using
1990-1993 sediment data (Strobel et al., 1995).
Because the geology contributing lithogenic material
to background sediments might be different in the
Gulf region from those in the NE, the procedure was
repeated using EMAP Gulf of Mexico 1991-1994 data.
Regression coefficients so obtained were similar to
those for the NE (within 30%) except for the elements
cadmium, copper, lead, and tin (Appendix 2, 2-1), and
of those, only the cadmium slope differed by more
than a factor of 2.
Our approach to aluminum normalization of Gulf of
Mexico EMAP data differs somewhat from that of
Summers et al., (1996). We chose to use the approach
outlined in Strobel et al., (1995) because it applies a
consistent model across all metals and makes no a
priori assumptions about which sediments comprise
background (Summers et al. applied different statisti-
cal transformations to different metals and eliminated
sediments from consideration as background on the
basis of sediment quality guidelines based on biologi-
cal response).
Measured and estimated background concentrations of
metals in post-Katrina sediments were compared with
those from the EMAP National Coastal Assessment
(NCA) 2002-2003 data. (NCA sediment metals data
from 2000-2001 were not included in the analysis
because of a shift in apparent concentrations of
some metals between the 2001 and 2002 samples.)
The comparison shows that metal contamination
in the coastal region is slight and not substantially
different from conditions prior to the hurricane.
Metal enrichment relative to background is generally
slightly higher in sediments from Lake Pontchartrain
than in Mississippi Sound sediments, but for most
metals, this enrichment factor is less than 3 (Table
4-4). Only cadmium was slightly more enriched in
sediments after Hurricane Katrina (Fig. 4-1). For a
few metals (Sn, Zn, and perhaps, Cu), the degree of
contamination was no higher but may be spread more
uniformly across the region (e.g., Sn in Fig. 4-2).
Tin appears to be perhaps the most highly enriched
Environmental Conditions in Northern Gulf of Mexico Coastal Waters Following Hurricane Katrina
17
-------
Estuary
Mississippi Sound
Lake
Pontchartrain
Sampling
Pre-
Katrina
Post-
Katrina
Pre-
Katrina
Post-
Katrina
Mean
S.D.
N
Mean
S.D.
N
Mean
S.D.
N
Mean
S.D.
N
AS
1.85
3.52
68
1.79
0.43
26
2.63
0.64
23
2.70
0.65
29
As
1.45
0.71
68
1.89
0.54
26
2.04
0.98
23
2.27
0.83
29
Cd
1.13
0.94
68
2.55
1.09
26
3.55
1.92
23
3.62
1.15
29
Cr
1.23
0.62
68
1.35
0.39
26
1.51
0.50
23
1.66
0.57
29
Cu
2.09
2.18
68
1.61
0.68
26
2.43
0.89
23
2.53
1.06
29
Fe
1.69
0.38
68
1.90
0.64
26
2.11
0.80
23
2.31
0.87
29
HS
1.03
0.74
68
1.25
0.45
26
1.66
0.79
23
1.57
0.64
29
Mn
2.30
1.06
68
2.05
0.84
26
4.17
2.14
23
3.90
1.77
29
Ni
1.42
0.78
68
1.60
0.62
26
1.87
0.74
23
2.15
0.86
29
Pb
1.62
0.57
68
2.03
0.42
26
2.35
0.67
23
2.54
0.73
29
Sb
1.02
0.73
68
1.14
0.37
26
3.98
4.81
23
1.80
0.49
29
Se
1.64
2.20
68
4.88
1.71
26
6.03
4.75
23
4.63
1.48
29
Sn
6.63
4.52
68
5.69
1.46
26
7.15
2.43
23
6.25
1.39
29
In
1.34
0.45
68
1.67
0.45
26
1.84
0.61
23
2.09
0.80
29
Table 4-4. Statistical summary of enrichment factors for metals in Lake Pontchartrain and Mississippi Sound sediments
pre- and post-Hurricane Katrina.
of the elements analyzed, but individual enrichment
factors are still less than 10X for almost all samples.
By comparison, enrichment factors of 20 to 100 X
are found for contaminant metals (e.g., zinc, copper,
lead, chromium, cadmium and silver) in sediments
from industrialized harbors, such as New Bedford,
Massachusetts, and even outside the harbor, enrich-
ment factors remain ~3 to 5X (Latimer et al., 2003).
4.3.2 Metals ESBs
The equilibrium partitioning sediment benchmark
(ESB) for metals mixtures utilizes the concept that
the bio-availability of cadmium, copper, lead, nickel,
silver, and zinc in a sediment can by predicted by
subtracting the concentration of acid volatile sulfide
(AVS) from the concentration of the simultaneously
extracted metals (SEM) isolated using the AVS
procedure, and then dividing the result by the fraction
of total organic carbon (foc) in the sediment [(SEM
- AVS)/ (foc)]. The (SEM - AVS)/ (foc) value is
interpreted as follows: sediments for which (SEM
- AVS)/ (foc) < 130 |imol/goc should not be toxic;
sediments for which 130 |imol/goc < (SEM -AVS)/
(foc) < 3000 |imol/gocmay be toxic to benthic organ-
isms, sediments for which (SEM -AVS)/ (foc) >3000
|imol/gocare likely to be toxic to benthic organisms
(USEPA, 2005).
The use of the (SEM - AVS)/ (foc) method on the post-
Katrina samples was complicated because neither AVS
nor SEM were measured on the samples (Appendix
2, 2-2a & -b). A worst-case substitution, however,
Lake Pontchartrain
O Measured Segment Concentrations
• Estimated Bkgd concentrations
Sound Lake Pontchatraln
D Measured Betfment Concentrations
• Estimated Bkgd c D
Fig 4-1. Cadmium in Gulf region sediments pre- and
post-Hurricane Katrina.
Fig 4-2. Tin in Gulf region sediments pre- and post-
Hurricane Katrina.
18
-------
was performed using total metals instead of SEM, and
setting the AVS equal to zero. The use of total metals
instead of SEM probably introduces a factor of conser-
vatism of approximately two. It is difficult to estimate
the level of conservatism added by setting AVS equal
to zero without some estimate of the AVS. Even using
these worst-case assumptions none of the samples
were above the 3000 |imol/gocbenchmark (which
would predict that the sediments should be toxic), and
most were barely above the 130 |imol/gocbenchmark
(below this value the sediments would be predicted to
be non-toxic) (Appendix 2, 2-3 a, b). Thus, given the
conservatism of assumptions used in the calculation,
it seems unlikely that cadmium, copper, lead, nickel,
silver, and zinc in these samples would pose much risk
to benthic organisms.
4.3.3 PAHs: ESBs
The ESB for polycyclic aromatic hydrocarbon (PAH)
mixtures utilizes narcosis and equilibrium partitioning
theories to estimate the toxic contribution of the PAHs
measured in a sample, and then sums those contribu-
tions (as toxic units) to estimate the toxicity of the
sample due to the presence of PAHs (USEPA, 2003a).
The benchmark is designed for use with measurements
from a suite of 34 PAHs. Correction factors have been
developed for use with data sets with 23 or 13 PAHs
(USEPA, 2003 a). The magnitude of the correction
factor used depends on the number of PAHs analyzed
and the degree of certainty desired in the extrapolation
from the full set of 34 PAHs to the analyzed set of
PAHs (Appendix 2, 2-4).
The post-Katrina samples had data appropriate for
use with extrapolation from a set of 13 PAHs, so
£ESGTUFOV 13 (toxic or benchmark units) values were
calculated (USEPA, 2003a). Only 12 samples had any
detectable total PAHs. The PAH ESB calculations
were made on the data from all of these samples. None
of these samples were higher than the benchmark (of
one toxic unit), even when using the largest correction
factor. This correction factor allows 99% confidence
that the guideline will be protective, given the ratio
of toxicity of 13 to 34 PAHs seen in field samples
(USEPA, 2003a). Given these results, it seems
unlikely that PAHs in any of these samples would
cause adverse impacts to benthic organisms.
4.3.4 Non-ionic Organic Chemicals: ESBs
Given an appropriate water-only toxicity value, like
the final chronic value (FCV) from a water quality
criterion, and a good estimate of the octanol-water
partition coefficient (KOW), it is theoretically
possible to calculate an ESB for any non-ionic organic
compound (USEPA, draft). ESBs are available for
four pesticides in the post-Katrina data set: alpha
endosulfan and beta endosulfan (USEPA, draft),
dieldrin (USEPA, 2003b) and endrin (USEPA, 2003c).
ESBs were also calculated for two other pesticides
for which KOWs and FCVs are available: heptachlor,
and toxaphene. Finally, an ESB was calculated for
Fipronil®, even though there is not as much informa-
tion on Fipronil®'s biological effects or partitioning as
there is for the other pesticides, because Fipronil® was
of special interest in the data set (Table 4-5).
No alpha endosulfan, beta endosulfan, heptachlor,
heptachlor epoxide, toxaphene, or dieldrin was
detected in any of the samples. Endrin was detected
in one sample, but the measured value (0.39 ng/g dry
wt, or 0.021 jig/gOC) was barely above the detection
limit and was well below the ESB for endrin (0.44
Hg/gOC).
Fipronil® is a relatively new insecticide that is used for
control of termites, fire ants, and other pests (USEPA,
1996). The fact that Fipronil® operates with similar
efficacy for many invertebrates has given rise to
concerns about impact on non-target organisms (Walse
et al., 2004).
The only available spiked sediment data for
Fipronil® is from a test with Amphiascus tenuremis,
a harpacticoid copepod (Chandler et al., 2004a). The
organic carbon content of the sediment was 3.85%
(G.T. Chandler, personal communication). There were
reproductive effects at all concentrations, including the
lowest tested, 1.7 jig/gOC. There was no increased
mortality at any concentration, including the highest
concentration tested, 7.8 jig/gOC. These results are
consistent with predictions derived using equilibrium
partitioning theory (USEPA, draft) and corresponding
water-only effects data (Chandler et al., 2004a).
A Fipronil® ESB of 0.044 ug/gOC was calculated
using a KOW of 4.01 and the lowest available chronic
value for an estuarine organism, < 0.005 |ig/L. This
value is for impaired reproduction in the mysid,
Americamysis bahia (USEPA, 1996). Of these 9
Environmental Conditions in Northern Gulf of Mexico Coastal Waters Following Hurricane Katrina
19
-------
Chemical
Dieldrin
Alpha endosulfan
Beta endosulfan
Endrin
Heptachlor
Heptachlor epoxide
Toxaphene
Fipronil®*
Fipronil®*
FCV (ug/L)
0.0019
0.0087
0.0087
0.0023
0.0036
0.0036
0.0002
0.005
0.005
Los KOW
6.26
5
5.5
4.01
4.68
Los KOC
6.15
4.92
5.41
3.94
4.60
ESB
(us/sOC)
28
0.05
0.24
0.44
5.13
0.30
0.05
0.0438
0.20
Source
U.S. EPA 2003 b.
(Dieldrin ESB.)
U.S. EPA draft.
(Compendium ESB.)
U.S. EPA draft.
(Compendium ESB.)
U.S.EPA2003c.
(Endrin ESB.)
Karickhoff and Long
1985. (KOW)
Karickhoff and Long
1985. (KOW)
Karickhoff and Long
1985. (KOW)
USEPA, 1996. (KOW
and mysid data)
SPARC and Mysid data
* A Fipronil® FCV is not available. The mysid chronic value (< 5 ng/L) was used for the
computation.
** KOC calculated using the formula KOC = KOW x 0.983 + 0.00028 (USEPA, Draft)
Table 4-5. Equilibrium partitioning derived sediment benchmarks for eight pesticides.
samples with detectable Fipronil®, seven exceeded the
ESB, (Table 4-6). If a less conservative Fipronil® ESB
is calculated using the higher KOW calculated by the
SPARC program (Hilal et al., 2004), only three of the
samples violate the criterion (Tables 4-5 and 4-6a &
4-6b).
The Fipronil® ESB needs to be interpreted with
caution because it is based on a single KOW determi-
nation and a single toxicity endpoint. However, given
the highly toxic nature of Fipronil®, its relatively low
KOW (USEPA, 1996), and the persistence and toxic-
ity of the breakdown products (Walse et al., 2004),
sediments with detectable Fipronil® should probably
prompt further investigation. USGS (2003) found that
Fipronil® did not accumulate in bedded sediment in
any appreciable amount, while the degradates accu-
mulated in sediments to much higher concentrations.
Therefore it is possible that some sediments that did
not show contamination with the parent compound,
have measurable concentrations of the degradates,
and possibly at higher concentrations than that of the
parent compound.
The fact that some of the post-Katrina sediments have
Fipronil® concentrations higher on an organic carbon
basis than those sediments shown to have reproductive
effects in Amphiascus (Chandler et al., 2004a) seems
to support the conclusion that Fipronil® may be of
concern in these sediments. This is especially true
because reproduction was affected in even the lowest
concentration in the Amphiascus test, and because the
other estuarine organisms tested to date with Fipronil®
are more sensitive (at least acutely) than Amphiascus
(USEPA, 1996).
These data need to be treated with caution, however,
because the sediments with the highest Fipronil®
concentrations on an organic carbon basis (KAT0009
and KAT0016) appear high primarily because their
TOC concentrations were very low. Also, high
20
-------
STA_NAME
KAT-0001
KAT-0002
KAT-0003
KAT-0004
KAT-0005
KAT-0006
KAT-0007
KAT-0008
KAT-0009
KAT-0010
KAT-0011
KAT-0012
KAT-0013
KAT-0014
KAT-0015
KAT-0016
KAT-0017
KAT-0018
KAT-0019
KAT-0020
KAT-0021
KAT-0022
KAT-0023
KAT-0024
KAT-0025
KAT-0026
KAT-0027
KAT-0028
KAT-0029
KAT-0030
F/pron//®
(ns/s)
0.47
0
0
0
0
0
0
0
1.4
0
0
0
0.77
0
0
0.61
0
0
0.53
0
0
0
0
0
0
0.36
0
0
0
0.79
roc
fo/\
(/a)
1.36
0.78
0.34
1.11
0.74
0.20
NA
1.42
0.03
0.04
0.46
1.11
0.82
0.32
0.87
0.02
1.88
0.66
0.19
0.44
0.19
0.72
0.65
1.06
0.83
0.79
0.03
0.96
0.54
0.22
F/pron//®
(VS/Soc)
0.03461
0
0
0
0
0
NA
0
4.087591
0
0
0
0.094052
0
0
2.935515
0
0
0.276618
0
0
0
0
0
0
0.045842
0
0
0
0.358114
Table 4-6a. FiproniP concentrations in sediment collected
from Mississippi Sound stations following Hurricane
Katrina.
Fipronil® concentrations in these samples do not
correlate with the observed absence of toxicity in
corresponding Microtox® assays.
As far as we know, there are no data available on
Fipronil® in the sediments of the Gulf and Lake
Pontchartrain before the hurricane, so it is not possible
to know if the hurricane had any effect on the concen-
trations of Fipronil® in these sediments.
STA_NAME
LP-0001
LP-0002
LP-0003
LP-0004
LP-0005
LP-0006
LP-0008
LP-0009
LP-0010
LP-0011
LP-0012
LP-0013
LP-0014
LP-0015
LP-0017
LP-0018
LP-0019
LP-0020
LP-0021
LP-0022
LP-0023
LP-0024
LP-0025
LP-0026
LP-0027
LP-0028
LP-0029
LP-0030
LPALT-0058
F/pron//®
(ns/s)
0
0
0.96
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0.55
0
0
0
roc
fo/\
(/a)
1.04
0.01
1.11
1.98
0.76
1.10
0.82
1.26
1.09
1.00
0.96
1.32
1.16
0.12
0.91
0.74
1.21
0.84
1.05
0.72
0.21
0.96
0.94
0.89
1.68
1.27
1.32
1.47
1.09
F/pron//®
(VS/Soc)
0
0
0.086878
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0.043478
0
0
0
Table 4-6b. FiproniP concentrations in sediment collected
from Lake Pontchartrain stations following Hurricane
Katrina.
4.4 Benthic community characteristics and
condition
A statistical comparison was performed with Mests to
assess the significance of mean differences in benthic
response variables (total faunal abundance, number of
taxa, H' diversity, and the benthic index) before (2000-
2004) vs. after (2005) the hurricane for each of the two
survey areas (Table 4-7). A listing of the individual
values of each variable by station is also provided in
Appendix 3. Results showed significant reductions
(at a = 0.05) in numbers of benthic taxa and total
faunal abundance (no/m2) following the hurricane at
21
-------
Abundance (ff/m2)
# Taxa (per grab)
H' (per grab)
Benthic Index
Lake Pontchartrain
Pre-Hurricane
Mean
(n = 46)
1428
6
1.52
3.21
Post-Hurricane
(n = 29)
175
3
1.12
3.38
P-Value
0.040*
0.002*
0.081
0.798
Mississippi Sound/Lake Borgne
Pre-Hurricane
Mean
(n = 165)
2835
22
3.23
5.02
Post-Hurricane
(n = 30)
1412
13
2.67
5.49
P-Value
0.010*
< 0.0001*
0.003*
0.393
Table 4-7. Comparison ofinfaunal abundance, number oftaxa, and H' diversity in Lake Pontchartrain and Mississippi
Sound/Lake Borgne before (2000-2004) versus after (2005) Hurricane Katrina. P-values (based on results of T-tests) are
also included. * indicates significant difference at ct=0.05.
sites in Lake Pontchartrain. Similarly, in Mississippi
Sound there were significant post-hurricane reductions
in numbers oftaxa, H' diversity, and total faunal
abundance. While the changes in these variables are
suggestive of hurricane-related impacts, there were no
significant differences in the benthic index between
pre- and post-hurricane periods in either survey area.
Box plots of these variables by year showed similar
results (Figs. 4-3, 4-4). There was a consistent pattern
of lower values of most benthic variables (number
of species, diversity, and density) after the hurricane.
In Mississippi Sound/Lake Borgne, the means and
ranges of these values over the various pre-hurricane
sampling periods were consistently higher than post-
hurricane values with little inter-
annual variability (Fig. 4-3). While
post-hurricane reductions in these
variables were also evident in Lake
Pontchartrain, there was consider-
able inter-annual variability prior to
the hurricane (Fig. 4-4). Means and
ranges of most variables (except the
benthic index) showed a downward
trend with time from 2000-2003,
signs of some recovery in 2004,
and a decline again in 2005 follow-
ing the passage of the hurricane.
Benthic abundance and richness
were especially reduced after the
hurricane with values at record lows.
The benthic index showed a similar
downward trend prior to the hurri-
cane in Lake Pontchartrain, but the
trend persisted into 2004 and was
followed by higher values in 2005.
Such data suggest that benthic
community structure was fairly
stable over time in Mississippi Sound/Lake Borgne
prior to the passage of Katrina (i.e., from 2000-2004)
and much more variable in Lake Pontchartrain. In
addition to such background variability in the latter
case, some hurricane-related changes in these assem-
blages occurred in both systems.
Comparisons also were made of the dominant (10
most abundant) taxa occurring before vs. after the
hurricane for both study areas (Table 4-8). There
were notable shifts in the composition and ranking of
these dominants between the pre- and post-hurricane
periods. In Lake Pontchartrain, only three taxa (the
polychaete Mediomctstus spp., bivalves of the family
Mactridae, and the bivalve Rcmgict cuneatd) occurred
Mississippi Sound / Lake Borgne
Post-
2000 2001 2002 2003 2004 Kntnnn
Post-
2000 2001 2002 2003 2004 Katrina
8000
7000
S1 6000
5 5000
| 4OOO
I 3000
| 2000
ffi 1000
0
I
2000 2001 2002 2003 2004 Katrina
12 --
10 --
Port
2000 2001 2002 2003 2004 Katrina
Fig 4-3. Comparison of observed ranges in various benthic parameters in
Mississippi Sound/Lake Borgne before (2000-2004) and after (2005) Hurricane
Katrina. Boxes are inter-quartile ranges, horizontal lines within boxes are medi-
ans, plus marks are means, and whisker endpoints are 5th and 95th percentiles.
22
-------
Lake Pontchartrain
Post-
2003 2004 Katrina
7000
6000
5000
4000
3000
2000
1000
2000 2001 2002 2003 2004 Katrina
2001 2002 2003 2004
2000 2001 2002 2003
Fig. 4-4. Comparison of observed ranges in various benthic parameters in Lake
Pontchartrain before (2000-2004) and after (2005) Hurricane Katrina. Boxes are
inter-quartile ranges, horizontal lines within boxes are medians, plus marks are
means, and whisker endpoints are 5th and 95th percentiles.
among the 10 most dominant taxa during both periods.
It is also interesting that the classic opportunistic/
pollution-tolerant polychaete Streblospio benedicti
(Pearson and Rosenberg 1978) was the top dominant
taxon after the hurricane but was ranked 18th in
dominance prior to the hurricane.
Similar changes in dominant taxa were evident within
the more open waters of Mississippi Sound/Lake
Borgne. Only two taxa (the polychaetes Mediomastus
ambiseta, Paraprionospio pinnatd) were among the
top-10 dominants both before and after the hurricane.
Although opportunistic species were present in
these waters during both
periods (e.g., Mediomastus and
Paraprionospio pinnata, Pearson
and Rosenberg 1978), Streblospio
benedicti did not appear as a
dominant in Mississippi Sound
samples until after the hurricane,
similar to its pattern of stronger
post-hurricane dominance in
Lake Pontchartrain.
While such results indicate
hurricane-related effects on
several benthic community
characteristics, pre- vs. post-
hurricane changes in benthic
condition based on the benthic
index were less apparent (Table
4-7, Figs. 4-3 & 4-5). For
example, in Lake Pontchartrain,
the proportion of estuarine area
with poor to intermediate benthic
condition after the hurricane was
more extensive than average
pre-hurricane conditions but was well within the range
observed over individual pre-hurricane sampling peri-
ods (Fig. 4-5a). In Mississippi Sound (Fig. 4-5b), the
proportion of area with poor to intermediate benthic
condition was less extensive after the hurricane than
in all but one of the pre-hurricane periods (i.e., 2000).
Also, as noted above, differences in mean values of
the benthic index between the two overall pre- vs.
post-hurricane periods were not statistically significant
(a = 0.05, Table 4-7) in either survey area.
PnB
2004 Katrina
B.
2000 2001 2002 2003 2004 2005
2000
2001
2002
2003
2004
2005
Fig. 4-5. Comparison of benthic condition in Lake Pontchartrain (A) and Mississippi Sound (B) before (2000-2004) vs.
after (2005) Hurricane Katrina. Good benthic condition: Benthic Index (Bl) > 5, intermediate: Bl = 3-5, poor: Bl < 3.
Environmental Conditions in Northern Gulf of Mexico Coastal Waters Following Hurricane Katrina 23
-------
Survey
Area
Lake
Pontchartrain
Mississippi Sound
Pre-Hurricane (2000-2004) Post-Hurricane (2005)
Taxa
(n=46)
Rang/a cuneata
Texadina sphinctos-
toma
Mediomastus spp.
Mulinia lateralis
Cerapus benthophilus
Probythinella loui-
sianae
Ischadium recurvum
Hobsonia florida
Mactridae
Amphicteis spp.
(n = 165)
Mediomastus ambi-
seta
Nemertea
Paraprionospio pin-
na ta
Owenia fusiformis
Scoletoma verrilli
Cerapus benthophilus
Caecum pulchellum
Microphiopholis atra
Paraonis fulgens
Cossura delta
Mean #
Ind./m2
278
199
111
110
82
76
72
60
45
39
475
112
105
68
54
53
49
47
43
43
%Cum.
Density
19
33
41
49
55
60
65
69
72
75
17
21
24
27
29
31
32
34
35
37
Occurrence
59
22
39
11
4
9
22
13
22
2
68
60
68
36
44
4
1
35
2
38
Taxa
(n = 29)
Streblospio benedicti
Coelotanypus spp.
Mediomastus spp.
Parandalia tricuspis
Rang/a cuneata
Mediomastus ambi-
seta
Mactridae
Americamysis almyra
Ameroculodes miltoni
Nemertea
(n = 30)
Paraprionospio pin-
na ta
Mediomastus spp.
Mediomastus ambi-
seta
Parandalia tricuspis
Lepidactylus triar-
ticulatus
Gemma gemma
Mysella planulata
Streblospio benedicti
Cossura soyeri
Lineidae
Mean #
Ind./m2
41
37
21
19
9
9
8
3
3
3
170
127
102
96
68
66
45
41
36
36
%Cum.
Density
24
45
57
67
73
78
82
84
86
88
12
21
28
35
40
44
48
51
53
56
Occurrence
48
59
21
21
14
28
10
7
7
10
73
60
53
43
3
3
20
37
33
33
Table 4-8. Comparison of dominant infaunal species (10 most abundant in decreasing order) in Lake Pontchartrain and
Mississippi Sound before (2000-2004) versus after Hurricane Katrina (2005). Also shown in parentheses is the number of
samples (n) for each sampling period combination.
Because of their relatively stationary existence within
sediments, benthic communities can serve as reliable
indicators of potential environmental disturbances
from a variety of stressors, including hypoxia,
sediment contamination, and organic enrichment.
Although benthic community data were available for
2000-2004, pre-hurricane data on chemical contami-
nants and other sediment-associated stressors (e.g.,
TOC as a measure of organic enrichment) were only
available for 2000-2003. Thus, the following analyses
of benthic condition in relation to these stressors are
based on comparisons of 2000-2003 data (pre-hurri-
cane) with 2005 data (post-hurricane). References to
the effects of DO and salinity, however, do include
2004 data (Figs. 4-6 and 4-7).
Patterns of benthic fauna in Mississippi Sound did
not appear to be strongly correlated with sediment
contaminants. Seventy percent of these waters had
a healthy benthos along with low levels of chemical
contaminants (below expected bio-effect ranges)
following the hurricane, compared to 55% prior to
it (Fig. 4-8a). Co-occurrences of poor-intermediate
benthic condition and high sediment contamination
represented only 1.7% of these waters before the hurri-
cane and were not observed at any of the post-hurri-
cane sites (Fig. 4-8a). High sediment contamination,
independent of benthic condition, in fact represented
only 4% of the area before the hurricane and 0% after.
This suggests that the limited contaminants present in
these open coastal waters of Mississippi Sound prior
to the hurricane may have been flushed farther from
the system with the passing of the storm.
24
-------
-
B.
Fig 4-6. Comparison of bottom-water dissolved oxygen Fig 4-7. Comparison of bottom-water salinity in Lake
(mg/L) in Lake Pontchartrain and Mississippi Sound before Pontchartrain and Mississippi Sound before (A; 2004) vs.
(A; 2004) vs. after (B; 2005) Hurricane Katrina. after (B; 2005) Hurricane Katrina.
A. Mt&sisuppi Sound
1.7 ±1.6
(4)
2.3±16
(5) -
^^^^M
4I±2.4
\ i . \ v
55 ±9.7
179)
(9)'
70 ±1*7
(211
6 Lake Pordctuitw
100-1
r»£F90«d wifflrws win
Degra
HMHrry Krthos «*h
HeMh/ BeiKhcs Mhoui
corajmiwfcn
40-
59.5 ±8.9
(22)
Fig. 4-8. Pre- vs. post-hurricane comparison of sediment quality in (A) Mississippi Sound and (B) Lake Pontchartrain,
based on combined measures ofbenthic condition and sediment contamination. Healthy benthos = Bl > 5; degraded
benthos = Bl <3 (poor condition) or Bl between 3-5 (intermediate). Contaminated sediment = One or more contaminants
in excess ofERM (from Long eta/., 1995), or mean ERM-Quotient > 0.062 (from Hyland etal., 2003).
Environmental Conditions in Northern Gulf of Mexico Coastal Waters Following Hurricane Katrina 25
-------
Given these results, it seems unlikely that chemical
contaminants were a major cause of the observed
changes in benthic communities. However, one
possible contributor may have been the insecticide
Fipronil®, which was detected in nine of the post-
Katrina sediment samples (see sections 4.3.4). The
two stations where Fipronil® concentrations were the
highest on an organic carbon basis (Mississippi Sound
stations KAT0009 and KAT0016) showed evidence
of degraded benthic condition in one or more of the
measured indicators (Appendix 3).
Dissolved oxygen (DO) levels also were higher in
Mississippi Sound following the hurricane, with only
46% of the area having high DO > 5 mg/L in 2004 and
96% having DO in this range after Hurricane Katrina
(Fig. 4-6). Similarly, the average percent area with
high DO over the five pre-hurricane sampling periods
(2000 to 2004) was much lower, 64% (graphic not
shown). None of these waters following the hurricane
had low DO (< 2 mg/L) in a range indicative of a high
risk of adverse effects on benthic fauna (Diaz and
Rosenberg 1995). Prior post-hurricane assessments
have shown that reductions in DO and salinity from
increased storm runoff can lead to adverse effects
on the benthos (Balthis et al., in press, Mallin et al.,
2002, Van Dolah and Anderson 1991, Boesch et al.,
1976). In the present study, any storm-related effects
on benthic fauna in Mississippi Sound (e.g., shifts
in dominant taxa and reductions in other variables
mentioned above) appear to have been related more to
changes in salinity than DO. For example, mesohaline
salinity occurred over a larger proportion of this
system after the hurricane in comparison to average
pre-hurricane levels (47% vs. 37% respectively,
Table 4-9). Prior to the hurricane, the majority of the
area (55% on average from 2000-2004) was in the
higher polyhaline salinity range. Fig. 4-7 provides a
spatial illustration of such changes based on a compar-
ison of post-hurricane salinities to the preceding
2004 sampling period. The spread of lower salinity
following the hurricane, especially pronounced in the
western portion of Mississippi Sound, is assumed to
be related to the extensive rainfall and storm runoff.
Bottom Salinity
Pre-
Hurricane %
Post-
Hurricane %
Lake Pontchartrain:
Olisohaline (<5)
Mesohaline (5-18)
Polyhaline (> 18-30)
Marine (>30)
69.4 ± 13.0
(34)
24.5 ±6.1
(12)
6.1 ±6.1
(3)
(0)
3.3 ±6.6
(1)
96.7 ±6.6
(29)
(0)
(0)
Mississippi Sound:
Olisohaline (<5)
Mesohaline (5-18)
Polyhaline (> 18-30)
Marine (>30)
1.4 ±2.8
(1)
36.7 ±5.0
(37)
55.3 ±3.1
(118)
6.5 ±3.1
(16)
(0)
46.7 ± 18.1
(14)
43.3 ± 10.9
(13)
10 ± 10.9
(3)
Table 4-9. Pre-hurricane (2000-2004) vs. post-hurricane
(2005) comparison of bottom salinity in Lake Pontchartrain
and Mississippi Sound. Included are the percent area ±
95% Cl (and number of stations) within each salinity zone.
were not accompanied by high levels of chemical
contaminants in sediments. Such conditions, repre-
senting about 60% of the area before the hurricane and
66% after, could be due to: (1) unmeasured chemical
contaminants and other sediment-associated stressors
(e.g., ammonia and sulfide in porewater), (2) chronic
low-DO problems prior to the hurricane in these more
confined waters, (3) other physical and biological
sources of disturbance, or (4) inherent uncertainty
in the predictive ability (classification efficiency) of
the benthic index. With respect to this latter point,
Engle and Summers (1999) note that, while the index
is a useful assessment tool, it delineates healthy
from impaired condition correctly about 74-77% of
the time, and thus is associated with some inherent
variability, as expected for an index that would be
applicable across a wide variety of Gulf of Mexico
estuarine environments.
Co-occurrences of poor-intermediate benthic condition Similar to Mississippi Sound, storm-related effects
and high sediment contamination were more evident
in Lake Pontchartrain, representing 8.1% of the area
before the hurricane and 13.8% after (Fig. 4-8b).
Lake Pontchartrain waters that had poor-intermediate
benthic condition, either before or after the hurricane,
26
on benthic fauna in Lake Pontchartrain (e.g., shifts
in dominant taxa and reductions in other benthic
community variables mentioned above) appear to have
been related more to changes in salinity than lowered
DO. Low DO (< 2 mg/L) was not observed in these
Environmental Conditions in Northern Gulf of Mexico Coastal Waters Following Hurricane Katrina
-------
waters following the hurricane, though it occurred in
10% of the area in the preceding year of 2004 (Fig.
4-6a), 38.5% of the area in 2003, and 12% of the area
on average over the four pre-hurricane years (graph-
ics not included). The pattern of change in salinity
in Lake Pontchartrain was opposite from that in
Mississippi Sound, with a post-hurricane shift toward
higher salinities. For example, most of the area before
the hurricane (69% on average from 2000-2004) was
in the oligohaline (< 5 ppt) range, whereas after the
hurricane most of the area (about 97%) was in the
higher mesohaline range (5-18 ppt) (Table 4-9). A
similar pattern is displayed when post-hurricane salini-
ties are compared to the preceding 2004 sampling
period (Fig. 4-7). This pattern was likely caused by
the large storm surge that brought saltier coastal water
into the lake.
Storm-related patterns of benthic fauna did not appear
to be linked to organic enrichment of sediments. No
samples following the hurricane in either survey
area had TOC at elevated levels (> 3.6 %) indicative
of conditions associated with a high risk of adverse
benthic effects (Hyland et al., 2005). All samples in
both survey areas after the hurricane had relatively low
to moderate levels of TOC below 2%. Throughout the
entire pre-hurricane (2000-03) data record, there were
only two stations in Lake Borgne (LAO 1-0026 and
LAO 1-0042) that had high TOC in the upper reported
bio-effect range (4.2% and 4.6% TOC, respectively).
In summary, there were notable changes in several
benthic community characteristics between the pre-
and post-hurricane periods that suggest storm-related
effects in both Lake Pontchartrain and the more open
waters of Mississippi Sound/Lake Borgne. These
included shifts in the composition and ranking of
dominant taxa and reductions in number of taxa, H'
diversity, and total faunal abundance. The benthic
index in general did not reveal such effects, though
there was a slight decline in the percentage of Lake
Pontchartrain waters with healthy benthic assemblages
after the hurricane in comparison to average pre-hurri-
cane periods (Figs. 4-5a, 4-8b). In Lake Pontchartrain,
considerably large portions of these waters had poor
to intermediate condition both before and after the
hurricane. In comparison, the majority of Mississippi
Sound waters had healthy benthic assemblages in both
post- and most pre-hurricane sampling periods, with a
small increase in the spatial extent of such condition
following the hurricane in comparison to average pre-
hurricane conditions (Figs. 4-5b, 4-8a). Any potential
storm-related effects on the benthos did not appear to
be linked to chemical contamination, organic enrich-
ment of sediments, or hypoxia at least as primary
causes. While increased mobilization of contaminants
may have contributed to such effects, storm-related
changes in salinity were a more likely cause of the
observed benthic effects in both survey areas. Storm
induced scouring of sediments could have contributed
as well.
4.5 Sediment Clostridium perfringens
Clostridiumperfringens is an anaerobic, gram posi-
tive, spore forming bacterium. It frequently occurs in
the intestines of humans and warm blooded animals
and as a result can be considered an indicator of
fecal waste. Spores of this organism can be found in
soils and sediments subject to human or animal fecal
pollution (Emerson and Cabelli, 1982; FDA, 2006).
Clostridium perfringens data were developed for
three post-hurricane cruises in 2005: NOAA National
Marine Fisheries Service sampling cruise on the
NOAA Ship Nancy Foster (September 13-16), NOAA
Mussel Watch field work assisted by the Louisiana
University Marine Consortium's (LUMCON) vessel
Acadiana (September 29 - October 10, 2006), and
the EPAs OSV Bold cruise (October 9-14, 2005).
Samples from all three cruises were analyzed using
consistent methods (summarized below) to allow for
the comparison of data resulting from the different
sampling areas.
Concentrations of C. perfringens have been deter-
mined in sediments from around the U.S. as recently
as the 1996-1997 biennial sampling period by NOAA's
Mussel Watch Project. The Project sampling sites are
generally located away from hotspots and so provide a
general overview of C. perfringens in U.S. coastal and
estuarine sediments. Sites for which concentrations of
C. perfringens were quantified ranged from a low of
5 CFUs/g dry weight to a high of 26,000 CFUs/g dry
weight. Of the 280 nationwide Mussel Watch monitor-
ing sites, 20 are located in the states of Louisiana,
Mississippi and Alabama. These 20 sites were
sampled immediately after the passage of Katrina to
determine the impact of major hurricanes and flushing
events on potential C. perfringens, and thus sewage
contamination in the sediments of the northern Gulf of
Mexico.
27
-------
Kilometers
• •
0 12.5 25 50
ALABAMA
FLORIDA
75
MISSISSIPPI
l
>
,•» °^B ^f.' lenreoonne •* ~-:\F
Bay -
Atchafalaya ^ /t
Bay »» ">'
„ ^S- ^ 1 '
l«
\
\
\
Path of
Hurricane Katrina
•
Integrated Contamination Assessment
^ NOAA | NOS | OR&R
(» NOAA | NMFS | NWFSC
<3 NOAA | NOS | NCCOS | NS&T
' 1 NOAA | NOS | NCCOS | CCEHBR & USEPA
Fig. 4-9 Sites sampled by EPA and NOAA after the passage of Hurricanes Katrina and Rita.
Fig. 4-10 Concentration (CFU/dry weight) of C. perfrin-
gens in sediments at Mussel Watch sites in Louisiana,
Mississippi and Alabama compared to average concentra-
tions of the Mussel Watch, National Marine Fisheries
Service and EPA sites; indicated as red, green and blue
lines, respectively.
Sampling cruises (Fig. 4-9) were conducted by
NOAA and the EPA with C. perfringem analyses all
performed by the same NOAA contract laboratory.
The C. perfringem concentration range for the 11 sites
collected during the NOAA National Marine Fisheries
Service cruise was 0-285 CFUs/g dry weight. For
the EPA OSV Bold cruise 26 sediment samples were
characterized for C. perfringem concentrations. The
concentration range was similar to that of the NMFS
data with the highest reported value being only
slightly higher. The concentration range was 0-292
CFUs/g dry. The NOAA sampling staged from the
Louisiana Marine Consortium vessel Acadiona was
nearly concurrent with that of the EPA cruise and was
conducted at the more in-shore sites of the Mussel
Watch Project. Concentrations for these sites (Fig.
4-10) ranged from a low of 71 CFUs/g dry weight at
Tiger Pass (on the west side of the Mississippi River
28 Environmental Conditions in Northern Gulf of Mexico Coastal Waters Following Hurricane Katrina
-------
Delta) to a high of 754 CFUs/g dry at Oyster Bayou
(the eastern boundary of Point au Fer Island, at the
lower extreme of Atchafalaya and Four League Bays).
Even though a sediment sample was collected at a
Lake Pontchartrain site, it did not have the highest
reported concentration; that site's concentration was
701 CFUs/g dry weight.
The post-hurricane sediment samples were in the
range of concentrations found for sediments collected
as part of the regular Mussel Watch but well below
the high concentration of 26000 CFU/g dry weight.
That high value was found at Rookery Bay, Henderson
Creek, Florida, in 1996. The next highest site concen-
trations for samples collected at that time in decreas-
ing order were: Mississippi River Tiger Pass (12,000
CFU/g dry weight), Louisiana; Everglades Faka Union
Bay, Florida (8,100 CFU/g dry weight); and Palos
Verdes, Royal Palms, California (6,600 CFU/g dry
weight. The highest C. perfringens concentrations in
samples for the Mussel Watch sampling of 1996 and
1997 exceeded all post-hurricane concentrations. In
nearly all cases, when older (1996) Mussel Watch
data were compared to the post-hurricane results,
including the site within Lake Pontchartrain, the older
non-hurricane affected sites had higher concentrations
of C. perfringens.
To put the post-hurricane C. perfringens data into
a broader context, data for a select group of marine
sewage dumpsites and outfalls were reviewed. Sewage
sludge from New York was disposed of at the Deep
Water Municipal Sewage Sludge Disposal site 106
miles off the coast of New Jersey (Hill et al., 1993).
Dumping reached a maximum in 1988 and decreased
until all dumping ceased in 1992 (Draxler et al.,
1996). The above authors collected sediments from the
106-mile dumpsite in 1991 and characterized surficial
sediments for C. perfringens. High concentrations
were found to exceed 9,000 CFU/g dry wt. High C.
perfringens concentrations were also found at other
sewage release sites, e.g., Massachusetts Bay (USGS
Open-File Report 01-356).
The post-Hurricane Katrina sampling results did not
exceed the highest C. perfringens concentrations
found from regular Mussel Watch sediment sampling
that occurred in the same region in 1996. Further,
the post-hurricane samples were well below the levels
measured in other parts of the U.S. directly exposed to
sewage, including the concentrations found from the
106-Mile Sewage Disposal Site and the C. perfringens
concentrations found at the Boston Sewage Outfall.
When the Mussel Watch sites that were sampled in
the 1990s were compared to the post-hurricane results
from the same sites, the 1990s data were usually
higher. Sites sampled by the OS V Bold cruise and the
Nancy Foster cruise generally exhibited lower concen-
trations of C. perfringens than did the Mussel Watch
sites. The most likely reason for this is that those sites
were further removed from human influence. While
numerous wastewater treatment facilities were flooded
during the hurricanes and raw sewage was released
into the environment, the amount of water introduced
both through rainfall and storm surge in all likelihood
diluted the sewage inputs and may have contributed to
a rapid flushing of the system.
The passage of the hurricanes does not appear to have
increased the concentration of C. perfringens in the
sediments of the hurricane-affected sites sampled.
5. Summary and Conclusions
Wave action, rainfall and runoff, collectively, contrib-
uted to the increased turbidity in the near coastal
waters affected by Katrina. Increases in dissolved
oxygen concentrations were attributed to these same
factors. Chlorophyll a concentrations increased
following the storm. Runoff and re-suspension may
have increased nutrient concentrations in these waters
resulting in a temporary increase in primary produc-
tion (Conner et al., 1989).
There were no exceedances of the ERM sediment
quality guideline values for chemical contaminants
for any of the sediments collected from Lake
Pontchartrain or Mississippi Sound. Lower threshold
ERL values were exceeded for arsenic, cadmium, and
nickel at several sites from both areas. Similar results
were obtained for samples collected prior to the hurri-
cane indicating very little change in the concentrations
and type of contaminants due to Katrina. The insec-
ticide Fipronil® was detected in post-hurricane sedi-
ments from both Lake Pontchartrain and Mississippi
Sound and appears to have been in a potential toxic
range at a few sites. However, no sediment quality
guidance value for, or pre-hurricane data on, Fipronil®
concentrations are available for comparison. When
the concentrations of contaminants were normalized
to aluminum concentrations, it was determined that
there was little risk to benthos for metals, PAHs, and
29
-------
pesticides, with the possible exception of Fipronil®.
There are insufficient data on the toxicity of Fipronil®
to determine potential risk to benthos. Two post-
Katrina stations in Mississippi Sound where Fipronil®
concentrations were highest did show some signs of
degraded benthic condition.
There were notable changes in several benthic
community characteristics between the pre- and post-
hurricane periods that are suggestive of storm-related
effects in both Lake Pontchartrain and the more open
waters of Mississippi Sound. These included shifts
in the composition and ranking of dominant taxa and
reductions in number of taxa, H' diversity, and total
faunal abundance. The benthic index in general did
not reveal such effects, though there was a slight
decline in the percentage of Lake Pontchartrain waters
with healthy benthic assemblages after the hurricane
than before. Any potential storm-related effects on
the benthos did not appear to be linked to chemical
contamination, organic enrichment of sediments, or to
lowered DO, at least as predominant causes. While
increased mobilization of contaminants may have
contributed to such effects (e.g., the possible case of
Fipronil®), storm-related changes in salinity were a
more likely cause of the observed benthic effects in
both survey areas. Storm-induced scouring of sedi-
ments could have contributed as well.
There were no differences in the concentrations of
C. perfringens in sediments prior to and following
the storm. Concentrations found following the storm
were well below those measured from sites throughout
the country which are exposed to sewage. Results
for samples collected from Mississippi Sound were
less than those collected at the in-shore sites used by
Mussel Watch. The low abundance of the organisms
was likely due to dilution and flushing of the systems
by Katrina.
The results from this study represent a snapshot
of ecological condition in coastal waters of Lake
Pontchartrain and Lake Borgne-Mississippi Sound
two months after the passing of Hurricane Katrina.
The comparison of ecological indicators before vs.
after the hurricane suggests considerable stability
of these systems with respect to short-term impacts.
While some ecological changes could be detected
(e.g., effects on benthic communities associated with
shifts in salinity), there was no consistent evidence to
suggest widespread ecological damage. These coastal
ecosystems in general appeared to have absorbed
much of the physical impact of the storm along with
any anthropogenic materials that may have been
mobilized by the floodwater and storm surge. Yet,
it must be noted that the present study, conducted
shortly after the hurricane, was not designed to assess
potential long-term chronic environmental effects.
Follow-up studies are recommended to evaluate such
impacts.
There are limitations associated with the data
presented in this report. The indicators used for
pre- versus post-storm comparisons are appropriate
for making estimates about the populations within
the geographic area studied, with known confidence.
Individual site-to-site comparisons are not supported
by this design. The study was logistically limited to a
45-day post storm response. Ideally the study would
have commenced within a few days or weeks follow-
ing the event, followed by a re-assessment during a
scheduled period later. Several of the indicators, i.e.,
waterborne contaminants and pathogens, have short
half lives and may not have been present 45 days
post-storm. There was still some public concern for
the presence of these materials in the estuaries. Our
study provided data to alleviate some of the concerns.
The data presented indicate that the coastal
ecosystems associated with Lake Pontchartrain and
Mississippi Sound responded to the stress created
by Hurricane Katrina much better than any of the
human-based systems. There may have in fact, been
some improvements to coastal ecosystem due to the
"flushing" provided by the storm surge and subsequent
freshwater inflow. Although, the loss of property and
life associated with Hurricane Katrina was devastat-
ing, this report demonstrates the resiliency of coastal
ecosystems in responding to extreme storm events.
30
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6. References
APHA 1998. Standard Methods for the Examination
of Water and Wastewater, 20th edition. American
Public Health Association, Washington, DC.
Balthis, W.L., J.L. Hyland, and D.W. Bearden. In
Press. Ecosystem responses to extreme natural
events: Impacts of three sequential hurricanes
in fall 1999 on sediment quality and condition of
benthic fauna in the Neuse River estuary, North
Carolina. Environ. Monitor. & Assess., 119: 367
-389.
Boesch, D.R, M.L. Wass, and R.W. Virnstein. 1976.
Effects of tropical storm Agnes on soft-bottom
macrobenthic communities of the James and York
estuaries and the Lower Chesapeake Bay. Ches.
Sci., 17(4): 246-259.
Chandler, G.T., T.L. Carey, D.C. Volz, S.S. Walse,
J.L. Ferry, and S.L. Klosterhaus. 2004a. Fipronil®
effects on estuarine copepod (Amphiascus tenui-
remis), development, fertility, and reproduction: a
rapid life-cycle assay in 96-well microplate format.
Environ. Toxicol. and Chem. 23:117-124.
Chandler, G.T., T.L. Carey, A.C. Bejarano, J. Fender,
and J.L. Ferry. 2004b. Population consequences
of Fipronil® and degradates to copepods at field
concentrations: an integration of life cycle testing
with Leslie matrix population modeling. Environ.
Sci. Technol. 38:6407-6414.
Cochran, W.G. 1977. Sampling Techniques. John
Wiley and Sons. 448pp.
Conner, W.H., Day Jr, J.W., Baumann, R. H, and J.M.
Randall. 1989. Influence of hurricanes on coastal
ecosystems along the northern Gulf of Mexico.
Wetlands Ecology and Management, 1(1): 45-56.
Diaz, R.J., and R. Rosenberg. 1995. Marine benthic
hypoxia: A review of its ecological effects and
the behavioral responses of benthic macrofauna.
Ocean. & Mar. Biol.: Ann. Rev., 33: 245-303.
Diaz-Ramos, S., Stevens, D.L., Jr and Olsen, A.R.,
1996. EMAP Statistical Methods Manual. Rep.
EPA/620/R-96/002, U.S. Environmental Protection
Agency, Office of Research and Development,
NHEERL-WED, Corvallis, Oregon.
Draxler, A.F.J., V. Zdanowicz, A.D. Deshpande, T
Finneran, L. Arlen and D. Packed. 1996. Physical,
chemical and microbial properties of sediments at
the 106-mile sewage sludge dumpsite. J. Marine
Env. Eng. 2:343-368.
Emerson, D.J. and V.J. Cabelli. 1982. Extraction
of Clostridium perfringens spores from bottom
sediment samples. Applied and Environmental
Microbiology 44(5) 144-1149.
Engle, V.D., J.K. Summers, and G.R. Gaston. 1994. A
benthic index of environmental condition of Gulf
of Mexico estuaries. Estuaries, 17(2): 372-384.
Engle, V.D. and J.K. Summers. 1998. Determining the
cause of benthic condition. Environ. Monitor. &
Assess., 51:381-397.
Engle, V.D. and J.K. Summers. 1999. Refinement,
validation, and application of a benthic condition
index for northern Gulf of Mexico estuaries.
Estuaries, 22(3A): 624-635.
FDA (Food and Drug Administration). 2006. Bad Bug
Book - Clostridium perfringens. http://www.cfsan.
fda.gov/~mow/chapll.html/April 5, 2006.
Hilal, S.H., L.A. Carreira, and S.W. Karikhoff. 2004.
Prediction of the solubility, activity coefficient,
gas/liquid and liquid/liquid distribution coef-
ficients of organic compounds. QSAR Comb. Sci.
23:709-720.
Hill, R.T., IT Knight, M.S. Anikis, and R.R.
Colwell. 1993. Benthic distribution of sewage
sludge indicated by Clostridium perfringens at a
deep-ocean dump site. Applied and Environmental
Microbiology 59(1) 47-51.
Hyland, J.L., W.L. Balthis, V.D. Engle, E.R. Long, J.F
Paul, J.K. Summers, and R.F. Van Dolah. 2003.
Incidence of stress in benthic communities along
the U.S. Atlantic and Gulf of Mexico coasts within
different ranges of sediment contamination from
chemical mixtures. Environ. Monitor. & Assess.,
81(1-3): 149-161.
Hyland, J.L., L. Balthis, I. Karakassis, P. Magni,
A.N. Petrov, J.P Shine, O. Vestergaard, and R.M.
Warwick. 2005. Organic carbon content of
sediments as an indicator of stress in the marine
benthos. MarEcol. Progr. Sen, 295: 91-103.
31
-------
IDEXX. 2004. Enterolert Test System Operations
Procedure. IDEXX Laboratories Inc. One IDEXX
Drive, Westbrook, Maine. 04092
Karickhoff, S.W. and J.M. Long. 1995. Internal
report on summary of measured, calculated, and
recommended log KQW values. Internal Report.
U.S. Environmental Protection Agency, Athens,
GA.
Latimer, J. S., W. S. Boothman, C. E. Pesch, G. L.
Chmura, V. Pospelova, and S. Jayaraman. 2003.
Environmental stress and recovery: the geochemi-
cal record of human disturbance in New Bedford
Harbor and Apponagansett Bay, Massachusetts
(USA). The Science of The Total Environment,
313:153-176.
Long, E.R., D.D. MacDonald, S.L. Smith, and ED.
Calder, 1995. Incidence of adverse biological
effects within ranges of chemical concentrations in
marine and estuarine sediments. Environ. Manage.,
19: 81-97.
MacDonald, D.D., R.S. Carr, ED. Calder, E.R.
Long, and C.G. Ingersoll. 1996. Development
and Evaluation of Sediment Quality Guidelines
for Florida Coastal Waters. Ecotoxicology 5:
253-278.
Mallin, M.A., M.H. Posey, G.C. Shank, M.R. Mclver,
S.H. Ensign, and T.D. Alphin. 2002. Impacts and
recovery from multiple hurricanes in a piedmont-
coastal plain river system. BioScience, 52(11):
999-1010.
NOAA/NCDC 2005. Climate of 2005. Summary of
Hurricane Katrina. NOAA National Climatic Data
Center (NCDC) http://www.ncdc.noaa.gov/oa/
climate/research/2005/katrina.html.
Pearson, T.H. and R. Rosenberg. 1978. Macrobenthic
succession in relation to organic enrichment and
pollution of the marine environment. Oceanogr.
Mar. Biol. Ann. Rev., 16: 229-311.
Ringwood, A. H, M. E. DeLorenzo, P. E. Ross, and
A. F. Holland. 1997. Interpretation of Microtox®
Solid Phase Toxicity Tests: The Effect of Sediment
Composition. Environmental Toxicology and
Chemistry 16 (No. 6): 1135-1140.
Shannon, C. E., Weaver, W. 1949. The mathematical
theory of communication. University of Illinois
Press, Urbana, Illinois. 117 p.
Smith, VH. 2006. Responses of estuarine and coastal
marine phytoplankton to nitrogen and phosphorus
enrichment. Limnology And Oceanography,
Volume: 51 , Number: 1,2 (JAN) , Page: 377-384.
Strobel, C.J., H.W. Buffum, S.J. Benyi, E.A.
Petrocelli, D.R. Reifsteck and DJ. Keith.
1995. Statistical Summary: EMAP-Estuaries
Virginian Province - 1990 To 1993. EPA/620/R-
94/026. U.S. Environmental Protection Agency,
National Health and Environmental Effects
Research Laboratory, Atlantic Ecology Division,
Narragansett, RI.
Summers, J.K. T.L. Wade, VD. Engle, and Z.A.
Maleab. 1996. Normalization of metal
concentrations in the Gulf of Mexico. Estuaries.
19:581-594.
USEPA. 1986. Ambient Water Quality Criteria
for Bacteria. United States Environmental
Protection Agency, Office of Water, Criteria and
Standards Division, Washington DC, 20460.
EPA/440/5-84-002.
USEPA. 1996. Fipronil®: New Pesticide Fact Sheet.
EPA-737-F-96-005. Office of Prevention,
Pesticides, and Toxic Substances, Washington, DC.
USEPA. 1999. Ecological Condition of estuaries in
the Gulf of Mexico. EPA 620-R-98-004. U.S.
Environmental Protection Agency, Office of
Research and Development, National Health and
Environmental Effects Research Laboratory, Gulf
Ecology Division, Gulf Breeze, FL.
USEPA. 2001. National Coastal Assessment: Field
Operations Manual. EPA/620/R-01/003. United
States Environmental Protection Agency, Office of
Research and Development, National Health and
Environmental Effects Research Laboratory, Gulf
Ecology Division, Gulf Breeze, FL. pp72.
USEPA. 2001. Environmental Monitoring and
Assessment Program (EMAP). National Coastal
Assessment Quality Assurance Project Plan 2001-
2004. United States Environmental Protection
Agency, Office of Research and Development,
32
-------
National Health and Environmental Effects
Research Laboratory, Gulf Ecology Division, Gulf
Breeze, FL. EPA/620/R-01/002.
USEPA. 2001. Protocol for developing pathogen
TMDLs. United States Environmental Protection
Agency, Office of Water, 4503F, Washington DC,
20460. EPA/84l/R-00/002.
USEPA. 2002. Research Strategy, Environmental
Monitoring and Assessment Program. EPA 620/R-
02/002. U.S. Environmental Protection Agency,
Office of Research and Development, National
Health and Environmental Effects Research
Laboratory, Research Triangle Park, NC.
USEPA. 2003a. Procedures for Deriving Equilibrium
Partitioning Sediment Guidelines (ESGs) for the
Protection of Benthic Organisms: PAH Mixtures.
EPA-600-R-02-013. Office of Research and
Development, Washington, DC.
USEPA. 2003b. Procedures for Deriving Equilibrium
Partitioning Sediment Guidelines (ESGs) for
the Protection of Benthic Organisms: Dieldrin.
EPA-600-R-02-010. Office of Research and
Development, Washington, DC.
USEPA. 2003c. Procedures for Deriving Equilibrium
Partitioning Sediment Guidelines (ESGs) for
the Protection of Benthic Organisms: Endrin.
EPA-600-R-02-009. Office of Research and
Development, Washington, DC.
USEPA. 2005. Procedures for Deriving Equilibrium
Partitioning Sediment Guidelines (ESGs) for the
Protection of Benthic Organisms: Metal Mixtures
(Cadmium, Copper, Lead, Nickel, Silver, and
Zinc). EPA-600-R-02-011. Office of Research and
Development, Washington, DC.
USEPA. Draft. Procedures for Deriving Equilibrium
Partitioning Sediment Guidelines (ESGs) for
the Protection of Benthic Organisms: Nonionics
Compendium. EPA-600-R-02-016. Office of
Research and Development, Washington, DC.
U.S. Geological Survey. 2003. Fipronil® and
degradation products in the rice-producing areas of
the Mermentau River Basin, Louisiana, February-
September 2000. USGS Fact Sheet FS-010-03.
March 2003.
USGS Open-File Report 01-356, Version 1.0. 2001.
Concentrations of Metals and Bacterial Spores
in Sediments near the Massachusetts Bay Outfall
before and after Discharge Began, http://pubs.usgs.
gov/of/2001/of01-356/July 17, 2006.
Van Dolah, R.F. and G.S. Anderson. 1991. Effects of
Hurricane Hugo on salinity and dissolved oxygen
conditions in the Charleston Harbor estuary. J.
Coastal Res. Special Issue No. 8: 83-94.
Walse, S.S., PL. Pennington, G.I. Scott, and J.L.
Ferry. 2004. The fate of Fipronil® in modular
aquatic mesocosms. J. Environ. Monit. 6:58-64.
33
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34
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Appendix 1
35
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Appendix 1.
Threshold/Guidance Values for Evaluating Water Quality*
Parameter
Good
Fair
Poor
Dissolved Oxygen
5mg/L
2-5 mg/L
<2 mg/L
Chlorophyll a
=5 ug/L
5-20 ug/L
>20 ug/L
Dissolved Inorganic Nitrogen
:0.1 mg/L
0.1-0.5 mg/L
'0.5 mg/L
Dissolved Inorganic Phosphorus
'-0.01 mg/L
0.01-0.05
mg/L
>0.05 mg/L
Water Clarity (% light transmission @ 1m)
>20%
10-20%
Water Quality
£ 1 indicator
scored fair
2 or more
indicators
scored fair or
1 indicator
scored poor
2 or more
indicators
scored poor
* U.S. Environmental Protection Agency(USEPA): 2004, 'National Coastal Condition Report II,' EPA-620/R-03/002. U.S.
Environmental Protection Agency, Office of Water, Washington, D. C.
36
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Appendix 2
37
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Appendix 2-1: Metal-aluminum regression parameters derived from EMAP Louisianan and
Virginian Provinces (1990-1994)
Element
AS
As
Cd
Cr
Cu
Fe
HS
Mn
Ni
Pb
Sb
Se
Sn
Zn
Province
Louisianan
Virginian
Louisianan
Virginian
Louisianan
Virginian
Louisianan
Virginian
Louisianan
Virginian
Louisianan
Virginian
Louisianan
Virginian
Louisianan
Virginian
Louisianan
Virginian
Louisianan
Virginian
Louisianan
Virginian
Louisianan
Virginian
Louisianan
Virginian
Louisianan
Virginian
Intercept
0.034
0.010
0.92
1.33
0.037
0.032
5.01
-1.53
-0.33
-2.37
-187
-738
0.010
0.004
21.3
75.9
-0.16
-2.70
1.51
2.47
0.16
0.05
0.053
0.060
0.16
0.22
3.53
0.07
0.0748
0.0117
1.00
1.08
0.1139
0.0275
7.73
10.03
2.14
3.96
4044
5655
0.0067
0.0094
53.8
51.4
3.75
4.62
2.49
4.99
0.0777
0.0659
0.0462
0.0672
0.172
0.377
11.4
16.5
277
181
239
469
180
273
234
465
266
368
266
525
265
329
203
288
306
476
198
430
275
334
263
400
178
330
252
350
0.559
0.431
0.801
0.491
0.444
0.470
0.850
0.794
0.821
0.703
0.874
0.855
0.538
0.500
0.813
0.686
0.811
0.744
0.947
0.644
0.462
0.503
0.475
0.475
0.709
0.730
0.892
0.782
Bold: normal distribution of residuals not obtained
38
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Appendix 2-2a: Metals chemistry data (dry weight) from Mississippi Sound samples.
STA_NAME
KAT-0001
KAT-0002
KAT-0003
KAT-0004
KAT-0005
KAT-0006
KAT-0007
KAT-0008
KAT-0009
KAT-0010
KAT-0011
KAT-0012
KAT-0013
KAT-0014
KAT-0015
KAT-0016
KAT-0017
KAT-0018
KAT-0019
KAT-0020
KAT-0021
KAT-0022
KAT-0023
KAT-0024
KAT-0025
KAT-0026
KAT-0027
KAT-0028
KAT-0029
KAT-0030
AS
UC/C
0.16
0.19
0.17
0.18
0.19
0.046
0.16
0.21
0.046
0.046
0.13
0.17
0.16
0.058
0.17
0.046
0.14
0.1
0.15
0.065
0.12
0.12
0.15
0.16
0.11
0.17
0.046
0.15
0.15
0.072
Cd
UC/C
1.4
1.5
1.2
1.3
1.5
0.14
1.1
1.4
0.14
0.14
0.74
1.2
0.97
0.19
1.2
0.14
1
0.62
0.84
0.4
0.62
0.71
0.87
1
0.78
1
0.14
1
1.2
0.42
Cu
UC/C
14
10.2
6.2
14.5
11
2.9
11.8
18.1
0.25
0.51
8.5
12.9
8.1
3.4
15.6
0.45
12.3
7
6.7
4.8
4
6
9.9
10.5
9.5
9
0.62
9.4
10.9
2.3
Ni
UC/C
28.7
18.3
13.7
26.9
20
4.3
18.8
33.2
0.28
0.57
15.9
23.3
14.3
6.6
25.1
0.4
22.2
12.4
13.7
9.4
11.1
10.2
16.5
19
20.7
16.1
0.69
18.2
20.2
3.5
Pb
UC/C
29.6
17.5
14.5
29.4
19.4
5.5
17.5
37.5
1.4
2.4
15
27.5
14.9
8.3
18.6
1
24.9
13
14
11.3
11.8
15.4
20
25.1
22.1
18.5
1.7
21.3
15.8
5.3
In
UC/C
114
58.4
45
102
65.1
17.9
61.1
126
2
3.4
54.5
95
49.2
28.3
77.7
2.7
100
45.4
47.6
37.8
34.4
48.9
59
80.7
86.3
62
2.9
74.1
59.5
12.6
39
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Appendix 2-2b: Metals chemistry data (dry weight) from Lake Pontchartrain samples
STA_NAME
LP-0001
LP-0002
LP-0003
LP-0004
LP-0005
LP-0006
LP-0008
LP-0009
LP-0010
LP-0011
LP-0012
LP-0013
LP-0014
LP-0015
LP-0017
LP-0018
LP-0019
LP-0020
LP-0021
LP-0022
LP-0023
LP-0024
LP-0025
LP-0026
LP-0027
LP-0028
LP-0029
LP-0030
LPALT-0058
AS
W/S
0.2
0.046
0.24
0.19
0.17
0.22
0.23
0.23
0.19
0.24
0.23
0.29
0.23
0.092
0.22
0.17
0.24
0.22
0.25
0.18
0.14
0.27
0.37
0.2
0.36
0.23
0.33
0.26
0.23
Cd
W/S
1.3
0.14
1.7
1.2
1.1
1.3
1.8
1.9
0.95
1.4
1.3
2.1
1.5
0.62
1.6
1.1
1.8
1.3
1.2
1.1
0.64
1.9
2.6
1.3
2.6
1.5
2
1.6
1.5
Cu
W/S
16.2
1.1
22.1
18.6
13.8
16.3
15.6
18.8
11.2
22.9
18
25.4
15.6
1.7
13.7
10.5
22.9
17.5
18.3
5.6
3.9
18.8
28.1
18
29.1
13.9
25.5
21.4
15.2
Ni
/'S/S
25.6
1.6
32.7
25.4
20.9
26.5
23.5
29.4
18.4
34.6
28.8
38.5
24.2
4
20.7
16.9
34.4
27.8
27.6
9.4
8.5
29.9
42.3
28.2
45.5
21
38.7
34.1
24.3
Pb
W/S
25.3
4
27.5
21.4
18.9
23.4
20.8
26.4
19.7
27.7
25.3
36.4
23.5
8.4
20.4
16.8
28.3
25.6
27.7
14
12.2
27.1
41.8
22.9
42.4
21.7
40.6
33.4
23
In
W/S
94.6
5.9
107
83.3
70.3
86.8
73.4
95.3
63.6
110
93.2
126
82.4
13.1
69.2
57.9
113
97.4
100
36.4
28.1
91.4
142
92.4
152
69
129
118
80.4
40
-------
Appendix 2-3a: Metals data (dry weight) from Mississippi stations
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47
-------
Appendix 2-3b: Metals data (dry weight) from Lake Pontchartrain stations
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42
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43
-------
Appendix 2-5: Equilibrium partitioning derived sediment benchmarks for eight pesticides.
Dieldrin
Alpha endosulfan
Beta endosulfan
Endrin
Heptachlor
Heptachlor epoxide
Toxaphene
Fipronil®*
Fipronil®*
FCV (us/L)
0.0019
0.0087
0.0087
0.0023
0.0036
0.0036
0.0002
0.005
0.005
Los KOW
6.26
5
5.5
4.01
4.68
Los KOC
6.15
4.92
5.41
3.94
4.60
ESB (us/sOC)
28
0.05
0.24
0.44
5.13
0.30
0.05
0.0438
0.20
U.S. EPA 2003 b.
(Dieldrin ESB.)
U.S. EPA draft.
(Compendium ESB.)
U.S. EPA draft.
(Compendium ESB.)
U.S. EPA2003c.
(Endrin ESB.)
Karickhoff and Long
1995. (KOW)
Karickhoff and Long
1995. (KOW)
Karickhoff and Long
1995. (KOW)
USEPA, 1996. (KOW and
mysid data)
SPARC and Mysid data
*A Fipronil® FCV is not available. The mysid chronic value (< 5 ng/L) was used for the computation.
** KOC calculated using the formula KOC = KOW x 0.983 + 0.00028 (USEPA, Draft)
44
-------
Appendix 2-6a: Fipronil® data from Mississippi stations.
STA_NAME
KAT-0001
KAT-0002
KAT-0003
KAT-0004
KAT-0005
KAT-0006
KAT-0007
KAT-0008
KAT-0009
KAT-0010
KAT-0011
KAT-0012
KAT-0013
KAT-0014
KAT-0015
KAT-0016
KAT-0017
KAT-0018
KAT-0019
KAT-0020
KAT-0021
KAT-0022
KAT-0023
KAT-0024
KAT-0025
KAT-0026
KAT-0027
KAT-0028
KAT-0029
KAT-0030
Fipronil®
(ng/g)
0.47
0
0
0
0
0
0
0
1.4
0
0
0
0.77
0
0
0.61
0
0
0.53
0
0
0
0
0
0
0.36
0
0
0
0.79
Fipronil®
(pg/ft)
0.00047
0
0
0
0
0
0
0
0.0014
0
0
0
0.00077
0
0
0.00061
0
0
0.00053
0
0
0
0
0
0
0.00036
0
0
0
0.00079
TOC
1.36
0.78
0.34
1.11
0.74
0.20
NA
1.42
0.03
0.04
0.46
1.11
0.82
0.32
0.87
0.02
1.88
0.66
0.19
0.44
0.19
0.72
0.65
1.06
0.83
0.79
0.03
0.96
0.54
0.22
Fipronil®
(p^/goc^)
0.03461
0
0
0
0
0
NA
0
4.087591
0
0
0
0.094052
0
0
2.935515
0
0
0.276618
0
0
0
0
0
0
0.045842
0
0
0
0.358114
45
-------
Appendix 2-6b: Fipronil® data from Lake Pontchartrain stations.
STA_NAME
LP-0001
LP-0002
LP-0003
LP-0004
LP-0005
LP-0006
LP-0008
LP-0009
LP-0010
LP-0011
LP-0012
LP-0013
LP-0014
LP-0015
LP-0017
LP-0018
LP-0019
LP-0020
LP-0021
LP-0022
LP-0023
LP-0024
LP-0025
LP-0026
LP-0027
LP-0028
LP-0029
LP-0030
LPALT-0058
Fipronil®
(ns/S)
0
0
0.96
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0.55
0
0
0
Fipronil®
(P?7?^
0
0
0.00096
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0.00055
0
0
0
roc
7.04
0.07
7.77
7.98
0.76
7.70
0.82
7.26
7.09
7.00
0.96
7.32
7.76
0.72
0.97
0.74
7.27
0.84
7.05
0.72
0.27
0.96
0.94
0.89
7.68
7.27
7.32
7.47
7.09
Fipronil®
(p£/£OC^)
0
0
0.086878
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0.043478
0
0
0
46
-------
Appendix 3
47
-------
Appendix 3-1: Summary of benthic variables by station in Mississippi Sound and Lake Borgne
before (n=172) and after (n=30) Hurricane Katrina.
Station
Taxa
Richness
(#/Srab)
Total
Abundance
(#/Srab)
Shannon-
Wiener H'
(Ios2)
Density
(#lm2)
Benthic Index
Mississippi Sound - pre-Katrina (n = 172)
ALOO-0020
ALOO-0022
ALOO-0023
ALOO-0024
ALOO-0025
ALOO-0038
ALOO-0044
AL0 1-0020
ALO 1-0022
AL0 1-0023
AL0 1-0024
AL0 1-0025
AL01-0038
ALO 1-0044
AL02-0020
AL02-0022
AL02-0023
AL02-0024
AL02-0025
AL02-0038
AL02-0044
AL03-0020
AL03-0022
AL03-0023
AL03-0024
AL03-0025
AL03-0038
AL03-0044
LAOO-0001
LAOO-0003
LAOO-0033
LAOO-0034
LA0 1-00 18
LA01-0026
LA0 1-0027
31
43
34
40
22
23
17
19
49
35
23
36
20
12
36
21
18
18
41
21
22
30
21
27
8
18
16
7
33
19
17
19
3
18
10
152
145
82
260
225
116
36
68
195
132
61
518
59
56
165
37
54
32
508
83
73
170
75
59
12
65
66
11
420
42
106
71
8
524
39
3.98
5.00
4.76
3.60
2.48
3.62
3.78
3.49
4.53
4.50
3.85
2.82
3.55
2.17
3.91
3.88
3.76
3.54
3.11
3.43
3.14
3.49
3.40
4.37
2.86
3.37
3.00
2.55
3.33
3.92
1.92
3.79
1.06
2.51
3.07
3040
2900
1640
5200
4500
2320
720
1360
3900
2640
1220
10360
1180
1120
3300
740
1080
640
10160
1660
1460
3400
1500
1180
240
1300
1320
220
10500
1050
2650
1775
200
13100
975
6.88
8.19
7.76
-1.73
4.22
-0.16
7.25
6.75
2.72
3.54
6.14
4.85
6.27
5.18
3.46
7.16
6.88
5.86
5.80
0.89
1.87
4.31
6.87
10.12
6.94
7.22
-0.75
7.05
1.82
11.04
5.81
9.83
1.52
10.59
1.78
48
-------
Stat/on
LA0 1-003 3
LA0 1-0042
LA02-0008
LA02-0013
LA02-0014
LA02-0015
LA03-0003
LA03-0010
LA03-0014
LA03-0015
LA03-0016
LA03-0018
MSOO-0013
LA04-0008
LA04-0010
LA04-0014
LA04-0015
LA04-0016
MSOO-0014
MSOO-0016
MSOO-0017
MSOO-0022
MSOO-0023
MSOO-0024
MSOO-0025
MSOO-0026
MSOO-0027
MSOO-0028
MSOO-0029
MSOO-0030
MSOO-0031
MSOO-0032
MSOO-0033
MSOO-0034
MSOO-0035
MS01-0026
MS01-0027
MS0 1-0028
Taxa
Richness
(#/Srab)
12
17
2
21
1
5
4
3
2
3
7
11
22
8
21
2
7
1
22
10
49
16
30
18
34
21
28
21
19
36
12
9
17
22
23
22
30
30
Total
Abundance
(#/Srab)
29
218
2
279
11
13
6
11
4
23
14
54
72
132
68
3
22
2
69
39
340
39
142
98
100
109
109
77
74
181
29
100
63
83
54
73
98
157
Shannon-
Wiener H'
(Ios2)
2.79
2.69
1.00
2.60
0.00
1.89
1.79
1.49
0.81
0.81
2.61
2.57
3.87
1.06
3.79
0.92
2.28
0.00
3.73
2.70
4.74
3.13
4.08
3.86
4.60
3.00
3.86
3.61
3.18
3.47
2.93
2.16
3.08
4.10
4.06
3.54
4.32
3.76
Density
(ff/m2)
725
5450
50
6975
275
325
150
275
100
575
350
1350
1440
3300
1700
75
550
50
1380
780
6800
780
2840
1960
2000
2180
2180
1540
1480
3620
580
2000
1260
1660
1080
1460
1960
3140
Benthic Index
1.98
9.22
-0.74
8.77
1.82
5.39
3.94
3.63
1.90
1.73
1.90
5.71
6.89
2.29
3.05
2.58
0.18
-1.22
7.10
5.39
-2.70
5.83
6.87
6.79
7.41
5.81
6.65
5.95
4.68
4.66
6.15
3.25
5.03
7.29
7.73
7.31
7.74
2.67
49
-------
Stat/on
AISO 7 -0029
MSO 7 -0030
A1S0 1 -003 1
AIS0 1 -0032
AIS0 1 -0033
AIS0 1 -0034
AIS0 1 -0035
AIS0 1 -003 6
AIS0 1 -003 7
AIS0 1 -0038
AIS0 1 -003 9
AIS0 1 -0040
MS0 1-0041
MS0 1-0042
AIS0 1 -0043
MS0 1-0044
MS0 1-0045
AIS0 1 -0046
MS01-0047
MS0 1-0048
AIS0 1 -0049
MS02-0018
MS02-0019
MS02-0021
MS02-0022
MS02-0023
MS02-0024
MS02-0027
MS02-0031
MS02-0032
MS02-0033
MS02-0035
MS02-0036
MS02-0037
MS02-0038
MS02-0039
MS02-0040
MS02-0041
Taxa
Richness
(#/Srab)
15
19
20
25
31
24
9
27
28
32
35
65
8
19
31
29
52
36
20
9
27
20
25
29
19
31
23
21
17
35
17
33
18
17
68
23
13
18
Total
Abundance
(#/Srab)
64
46
120
86
151
83
12
67
94
133
116
332
22
65
170
196
400
164
81
31
133
87
164
113
108
97
198
192
117
121
332
215
67
147
394
260
188
369
Shannon-
Wiener H'
(Ios2)
2.64
3.38
3.40
4.20
3.78
4.15
3.08
4.32
3.95
3.20
4.24
5.12
2.70
3.65
4.36
3.68
4.20
4.23
3.35
1.95
3.57
3.50
3.05
3.83
3.53
4.16
3.12
2.30
3.17
4.12
1.98
3.66
3.30
2.82
5.08
1.83
2.18
2.23
Density
(ff/m2)
1280
920
2400
1720
3020
1660
240
1340
1880
2660
2320
6640
440
1300
3400
3920
8000
3280
1620
620
2660
1740
3280
2260
2160
1940
3960
3840
2340
2420
6640
4300
1340
2940
7880
5200
3760
7380
Benthic Index
6.55
2.15
6.76
7.54
2.00
7.65
2.04
7.91
7.05
-0.81
8.67
2.99
7.83
7.33
8.16
5.91
-1.62
8.15
6.61
5.05
7.22
6.83
4.89
7.29
6.31
7.13
5.05
3.23
6.53
7.19
2.48
-0.75
3.28
4.31
8.24
2.72
3.58
4.66
50
-------
Stat/on
MS02-0042
MS02-0043
MS02-0044
MS02-0045
MS02-0046
MS02-0048
MS03-0010
MS03-0016
MS03-0018
MS03-0019
MS03-0023
MS03-0024
MS03-0028
MS03-0029
MS03-0031
MS03-0033
MS03-0034
MS03-0035
MS03-0036
MS03-0037
MS03-0038
MS03-0039
MS03-0040
MS03-0041
MS03-0042
MS03-0043
MS03-0044
MS03-0045
MS03-0046
MS03-0048
MS04-0016
MS04-0017
MS04-0018
MS04-0020
MS04-0021
MS04-0022
MS04-0027
MS04-0029
Taxa
Richness
(#/Srab)
32
18
21
14
22
11
11
11
14
31
24
25
16
16
34
25
34
41
8
14
28
22
14
35
21
11
7
32
26
10
25
40
14
21
26
19
28
29
Total
Abundance
(#/Srab)
620
60
197
126
125
49
132
14
58
263
126
117
27
122
96
92
291
206
20
59
57
170
64
210
87
20
15
204
178
61
122
415
110
94
133
114
177
153
Shannon-
Wiener H'
(Ios2)
2.57
3.52
2.96
1.60
3.07
2.54
1.40
3.38
3.45
3.05
3.57
3.86
3.75
2.84
4.54
3.81
2.79
4.34
2.32
2.77
4.45
3.60
2.65
3.99
3.88
3.28
2.52
3.97
3.66
2.37
3.47
3.32
2.05
3.82
3.77
3.29
3.83
3.41
Density
(ff/m2)
12400
1200
3940
2520
2500
980
2640
280
1160
5260
2520
2340
540
2440
1920
1840
5820
4120
400
1180
1140
3400
1280
4200
1740
400
300
4080
3560
1220
2440
8300
2200
1880
2660
2280
3540
3060
Benthic Index
-0.38
8.29
5.22
7.18
5.60
4.56
1.57
8.13
7.20
0.83
-0.36
7.26
7.75
5.65
7.92
7.26
4.30
8.04
5.34
4.49
8.55
6.56
4.97
7.29
7.89
2.54
5.61
7.22
7.80
-1.60
6.03
-3.98
4.81
6.77
6.36
6.48
6.50
5.70
Environmental Conditions in Northern Gulf of Mexico Coastal Waters Following Hurricane Katrina
51
-------
Stat/on
MS04-0030
MS04-0032
MS04-0033
MS04-0034
MS04-0036
MS04-0037
MS04-0038
MS04-0039
MS04-0040
MS04-0041
MS04-0042
MS04-0043
MS04-0044
MS04-0046
MS04-0047
MS04-0048
Taxa
Richness
(#/Srab)
14
23
67
13
27
23
13
13
51
14
34
15
56
23
46
17
Total
Abundance
(#/Srab)
33
120
589
44
159
136
33
30
749
58
353
58
955
290
501
112
Shannon-
Wiener H'
(Ios2)
3.22
3.85
3.70
3.06
4.01
3.66
3.33
3.30
3.58
3.10
3.12
2.92
3.75
3.47
3.79
1.92
Density
(ff/m2)
660
2400
11780
880
3180
2720
660
600
14980
1160
7060
1160
19100
5800
10020
2240
Benthic Index
6.93
6.98
-3.61
6.05
2.79
6.55
6.55
6.94
-1.31
5.85
6.00
6.36
5.77
2.73
6.28
2.58
Mississippi Sound - post-Katrina (n = 30)
KAT-0001
KAT-0002
KAT-0003
KAT-0004
KAT-0005
KAT-0006
KAT-0007
KAT-0008
KAT-0009
KAT-0010
KAT-0011
KAT-0012
KAT-0013
KAT-0014
KAT-0015
KAT-0016
KAT-0017
KAT-0018
KAT-0019
KAT-0020
KAT-0021
15
8
9
21
8
27
9
7
12
6
11
13
6
28
11
5
19
7
6
17
9
64
22
45
97
46
110
18
16
159
90
37
66
15
63
26
15
126
25
48
60
22
3.17
2.57
2.31
3.14
1.91
3.58
2.63
1.92
2.06
0.67
2.54
2.93
1.69
4.44
2.79
1.93
2.58
2.07
1.96
3.50
2.80
1600
550
1125
2425
1150
2750
450
400
3975
2250
925
1650
375
1575
650
375
3150
625
1200
1500
550
5.02
6.43
4.53
5.32
3.94
6.09
5.17
5.43
2.48
6.35
5.87
5.05
5.49
7.08
6.55
3.77
4.78
5.11
2.54
6.20
7.47
52
-------
Stat/on
KAT-0022
KAT-0023
KAT-0024
KAT-0025
KAT-0026
KAT-0027
KAT-0028
KAT-0029
KAT-0030
Taxa
Richness
(#/Srab)
21
3
13
20
7
18
18
17
9
Total
Abundance
(#/Srab)
101
10
40
64
52
45
81
94
37
Shannon-
Wiener H'
(Ios2)
3.52
1.30
3.06
3.84
2.12
3.55
3.56
3.69
2.30
Density
(ff/m2)
2525
250
1000
1600
1300
1125
2025
2350
925
Benthic Index
4.27
4.33
5.87
6.29
3.48
8.47
6.36
8.91
6.03
Environmental Conditions in Northern Gulf of Mexico Coastal Waters Following Hurricane Katrina
53
-------
Appendix 3-2: Appendix 3-2: Summary of benthic variables by station in Lake Pontchartrain
before (n=47) and after (n=30) Hurricane Katrina.
Station
Taxa
Richness
(#/Srab)
Total
Abundance
(#/Srab)
Shannon-
Wiener H'
(Ios2)
Density
(ff/m2)
Benthic Index
Lake Pontchartrain - pre-Katrina (n = 47)
LAOO-0023
LAOO-0024
LAOO-0025
LAOO-0030
LAOO-0031
LAOO-0032
LA0 1-00 13
LA0 1-00 14
LA0 1-00 15
LA0 1-00 16
LA0 1-00 17
LA0 1-0041
LA01-0047
LA0 1-0048
LA02-0001
LA02-0002
LA02-0003
LA02-0004
LA02-0005
LA02-0006
LA02-0007
LA02-0009
LA02-0011
LA02-0012
LA03-0001
LA03-0006
LA03-0008
LA03-0011
LA03-0012
LA03-0013
LA03-0017
LA03-0019
7
13
8
4
16
14
5
11
2
10
4
6
5
9
4
2
10
1
2
1
8
3
0
7
4
5
0
12
3
1
1
3
15
104
41
6
61
140
15
39
11
24
11
10
10
23
6
2
24
1
2
1
35
11
0
115
39
28
0
279
25
3
11
6
2.42
2.85
2.35
1.79
3.37
2.08
1.77
2.83
0.44
3.12
1.28
2.45
2.17
2.63
1.92
1.00
2.94
0.00
1.00
0.00
2.43
1.10
0.00
1.94
1.00
1.59
2.08
1.27
0.00
0.00
1.46
375
2600
1025
150
1525
3500
375
975
275
600
275
250
250
575
150
50
600
25
50
25
875
275
0
2875
975
700
0
6975
625
75
275
150
4.36
4.74
5.69
5.87
8.04
3.03
4.10
7.03
-0.79
6.27
2.56
6.48
5.71
7.34
8.10
3.20
8.16
1.82
3.26
-1.22
7.12
4.49
1.82
4.22
1.67
3.48
1.82
4.86
2.87
-1.22
-1.22
4.39
54
-------
Stat/on
LA03-0020
LA03-0022
LA03-0023
LA03-0024
LA03-STR03-01
LA04-0001
LA04-0002
LA04-0003
LA04-0005
LA04-0006
LA04-0007
LA04-0011
LA04-0012
LA04-0013
Taxa
Richness
(#/Srab)
2
2
3
8
1
4
7
17
1
11
2
8
3
15
Total
Abundance
(#/Srab)
6
21
44
37
4
12
50
802
3
57
35
206
6
246
Shannon-
Wiener H'
(Ios2)
0.65
0.45
0.31
2.10
0.00
1.73
1.93
2.18
0.00
2.43
0.42
2.05
1.25
2.97
Density
(#lrrf)
150
525
1100
925
100
300
1250
20050
75
1425
875
5150
150
6150
Bent hie Index
1.51
-0.11
0.13
6.67
-1.22
-1.56
-1.24
1.97
-1.22
1.26
0.63
6.48
1.85
4.40
Lake Pontchartrain post-Katrina (=29)
LP-0001
LP-0002
LP-0003
LP-0004
LP-0005
LP-0006
LP-0008
LP-0009
LP-0010
LP-0011
LP-0012
LP-0013
LP-0014
LP-0015
LP-0017
LP-0018
LP-0019
LP-0020
LP-0021
LP-0022
1
2
1
3
4
2
0
3
2
2
1
1
4
10
3
4
0
3
3
2
1
2
1
27
6
4
0
3
2
2
3
2
11
16
3
10
0
3
8
5
0.00
1.00
0.00
1.12
1.79
0.81
1.58
1.00
1.00
0.00
0.00
1.28
3.02
1.58
2.17
1.58
1.56
0.72
25
50
25
675
150
100
0
75
50
50
75
50
275
400
75
250
0
75
200
125
-3.01
3.18
-3.01
2.23
4.43
3.31
1.82
5.53
4.19
3.18
1.82
1.82
4.90
6.96
4.47
1.82
1.82
5.62
4.29
1.80
Environmental Conditions in Northern Gulf of Mexico Coastal Waters Following Hurricane Katrina
55
-------
Stat/on
LP-0023
LP-0024
LP-0025
LP-0026
LP-0027
LP-0028
LP-0029
LP-0030
LPALT-0058
Taxa
Richness
(#/Srab)
9
2
2
2
2
6
3
2
4
Total
Abundance
(#/Srab)
37
2
3
2
11
20
4
8
7
Shannon-
Wiener H'
(Ios2)
2.30
1.00
0.92
1.00
0.44
2.32
1.50
0.95
1.84
Density
(#lrrf)
925
50
75
50
275
500
100
200
175
Bent hie Index
7.36
4.24
2.92
3.24
2.59
6.77
4.58
2.82
6.25
56
-------
57
-------
&EPA
United States
Environmental Protection
Agency
Office of Research and Development
Washington DC 20460
Official Business
Penalty for Private Use
$300
Recvcled/Recyclable
Printed with vegetable-based ink on
paper that contains a minimum of
50% post-consumer fiber content
processed chlorine free
------- |