This document analyzes the potential ecological impacts of a leak from a natural gas liquids (NGL) pipeline running beneath Lake Herrington on the white bass population. A leak could introduce NGLs like ethane, propane and butane into the lake surface where white bass mate and feed in spring. Studies show hydrocarbons like these can cause fish death, disrupt behaviors, and harm biological functions. A spring leak in particular could drastically reduce white bass numbers through impacts on mating and food availability. This could disrupt the food chain by reducing a top predator and allowing overpopulation of smaller fish normally eaten by white bass. While impacts are difficult to predict precisely, a leak appears likely to negatively affect the local economy by reducing pri

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Mariah Harrod
Professor Anne Lubbers
ENS 270
28 April 2016
Population Regulation and Food Chain Impacts of NGLs on White Bass in Lake Herrington
In August 2013, Kinder Morgan Energy Partners announced plans to repurpose an
existing natural gas pipeline with natural gas liquids for plastic manufacturing (“The Utica
Marcellus Texas Pipeline Project”). Natural gas liquids (NGLs) are the denser hydrocarbons of
natural gas including ethane, propane, butane, isobutene, pentanes, and naphtha (Keller 6). Due
to the higher density of natural gas liquids, the conversion necessitates that the pipeline be
lowered beneath Lake Herrington (over which it is currently suspended) to maintain high
pressure, low temperature, and stable support to prevent ruptures (Kocher; Keller 27).
Underlying concerns for adding pressure to the pipeline and reversing the flow, some worry that
the 70 year old pipeline is dilapidated. Indeed, pipeline age positively correlates with corrosion
and leaking (Kiefner and Rosenfald 21). Due to the relatively high probability of a leak, it is
important to estimate the ecological ramifications of NGL exposure before deciding how our
community should react to this imposition.
In an environmental impact statement, the Bureau of Land Management hastily dismissed
concerns over NGLs affecting aquatic organisms with the explanation that these chemicals are
volatile and thus ephemeral; however, others believe that the heavier components of natural gas
will pool at Herrington’s surface and only gradually dissolve (Bennett 11; Miles). Local chemist
Preston Miles predicts that the NGLs transported in the pipe will predominantly include ethane,
propane, and butane, with smaller percentages of pentanes and denser hydrocarbons in which the
heavier components’ high boiling points foretell that a leak will result in largely insoluble liquid

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hydrocarbons lingering for years to come in Lake Herrington. Accordingly both the immediate
aftermath and lasting influence of these substances on aquatic organisms should be considered.
Fortunately (or perhaps unfortunately, as this may merely point to insufficient research), Lake
Herrington does not house any listed endangered or threatened species. However, this body of
water provides habitat for prized sport fish which provide profitable tourism, recreation, and
food for the community (“Herrington Lake”). One such fish is the white bass, Morone chrysops,
whose population is currently K-selected but in the case of an NGL spill may become r-selected
and produce a trophic cascade.
The impact of natural gas liquids on biological functions has been largely neglected by
research (Patin). Therefore, an ecological analysis of an NGL leak relies heavily on extrapolating
from studies and experiments performed in regard to related hydrocarbons. A bio-assay and
chemical analysis in Texas found that synthetic rubber production using hydrocarbons such as
butane created a waste detrimental to aquatic life (Marek 1-7). At just 2% concentration, all fish
test subjects died within three hours (4). Additionally, natural gas (comprising ethane, propane,
butane, etc.) spills in water—as in the Sea of Asov—caused “mass mortality” of fish and other
aquatic organisms (Patin). These deaths can be attributed to characteristics of hydrocarbons in
conjunction with biological attributes of fish. Gas—as much of these leaked NGLs will become
upon leaking into the water—is quickly absorbed by fish and damages the nervous and endocrine
systems as well as blood production (Patin). Marek and Patin both observed that moderate
hydrocarbon concentration exposure produced evident discomfort, loss of equilibrium, twitching,
leaping out of the water, faster respiration, and dispersal behavior (Marek 7; Patin). In addition,
more gradual reactions occur from repeated exposure as might be the case if the fish did not at
the time of the leak absorb sufficient levels of slowly dissolving NGLs to perish. To discern how

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these morbid results translate into an ecological impact in Lake Herrington, the behaviors and
functional role of the white bass must be evaluated.
White bass are schooling fish who mate in spring by darting to the surface and feed by
driving prey upward (“White Bass”). Thus, what pools on the water could severely impact the
ability of the population to reproduce and gain food for survival. NGLs have lower density than
water, and so a leak beneath Herrington would push ethane, propane, butane, and the heavier
hydrocarbons to the surface where—left untouched by humans—they would either evaporate or
form a pool and gradually dissolve (Miles). Thus, the white bass population density would be
most tragically affected during the spring if surface mating aggregation was interrupted (in the
case of low NGL concentration causing dispersal) or if extensive death produced an Allee effect.
In the latter case, the few remaining survivors in the population would be hard-pressed to find
mates and restore the original population density. A leak during the spring—when warm
temperatures promote reproduction and accelerate metabolism causing higher poison
consumption—would drastically reduce bass numbers more so than a leak another time of year.
The white bass was once the top open water predator in Kentucky reservoirs but has since
been supplanted by two introduced relatives—the striped and hybrid striped bass—whose
competition regulates white bass population densities (“White Bass”). The current population
regulation of white bass is K-selection because the environment provides accessible resources
and minimal stress, and competition for prey limits the white bass numbers through negative
feedback loops (Krebs 145). The population rises above carrying capacity, and fish unable to
access food die and decrease the population density to gradually creep back above this threshold
in a fluctuating cycle. If the Kinder Morgan pipeline broke beneath Lake Herrington, it is
probable that many fish would immediately die as a result. The lingering, gradually dissolving

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hydrocarbons would continue poisoning the bass populations to disrupt nervous, cardiovascular,
and endocrine systems vital for survival and reproductive behavior. Without restocking the lake,
white bass will likely remain below-carrying capacity densities. Accordingly, competition would
no longer be a regulating factor; the density independent factor of toxic stress tolerance would
limit the extent to which the white bass could survive and reproduce. If this selection were to
continue over several reproductive cycles, this stress tolerance rather than superior competitive
ability would likely become more pronounced in the population.
Gizzard shad is the primary food source of white bass, the latter who supplement their
diets with shiners, chubs, worms, insects, mollusks, and plankton in accordance with life stage
and seasonal prey availability (“White Bass”). Unlike white bass and its closely related surface
competitors, gizzard shad primarily feed at the bottom of bodies of water, as evidenced by sand
found in their stomachs (“Habitat Suitability Model Index” 13). Additionally, they filter feed
zooplankton in the limnetic zone (13). This predatory consumption regulates populations of these
plankton, the latter which many larval sport fishes—including white and striped bass—consume
(Dettmers and Stein 12). If the pipeline leaked and NGLs floated to the surface where bass and
not gizzard shad predominantly feed and mate, it is possible that these top predators would suffer
greater population losses. Conversely, it might also be true that the gradual dissolution of these
hydrocarbons will be superlatively toxic to smaller fish—such as the gizzard shad—due to lower
tolerance limits. The production of either outcome depends upon the season, the concentration of
NGLs, and whether the surface NGLs are treated (such as through burning) or left untreated. If
the former prediction is the case and the bass suffer greater proportional population losses than
the gizzard shad, a trophic cascade would occur in which virtually predator-free small fish
normally eaten by bass may maintain abnormally high populations. In this case, gizzard shad’s

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prey, zooplankton, would be overexploited to the detriment of bass young sharing that food
source and compound the already severe losses of these top predator fish if the leak occurs
following spring spawning (Dettmers and Stein 12).
Ecosystems are complex, and science is intentionally narrow. In predicting the effects of
an NGL spill on white bass in Lake Herrington, we operate under the premises that the NGLs in
the pipeline will be of a particular composition, that the pipeline will break in a certain location
(though this may be unlikely), that timing will produce highly different results due to variable
species behavior, and that other factors might not counteract the projected outcome. If a leak
does occur, I believe that sport fish populations will plummet to the detriment of the local
economy. State-funded restocking programs previously employed in low bass population periods
will likely be reinstated, expending heavily contested tax revenue. But the likelihood of such an
incident happening at a particular time as to truly devastate this ecosystem is probably low, and
other factors such as gas flammability and the absence of economic benefit to the community
should be granted greater consideration in deciding to oppose this pipeline transition.

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Works Cited
Bennett, Robert A. “Final: Overland Pass Natural Gas Liquids Pipeline Environmental
Impact Statement.” Bureau of Land Management 1 (2002). N.p., Web. 23 Apr. 2016.
Dettmers, John M., and Roy A. Stein. “Food Consumption by Larval Gizzard Shad:
Zooplankton Effects and Implications for Reservoir Communities.” Transactions of the
American Fisheries Society 121.4 (1992): 494-507. Web. 25 April 2016.
“Habitat Suitability Index Model and Instream Flow Suitability Curves: Gizzard Shad.” U.S.
Geological Survey National Wetlands Research Center. U.S. Department of the Interior
Fish and Wildlife Service, Sep. 1985. Web. 25 April 2016.
“Herrington Lake.” Kentucky Tourism. Kentucky Department of Travel, 2016. Web. 23 April
2016.
Keller, Anne B. “NGL 101- The Basics.” U.S. Energy Information Administration.
Midstream Energy Group, 6 Jun. 2012. Web. 21 Apr. 2016.
Kiefner, John F., and Michael J. Rosenfeld. “The Role of Pipeline Age in Pipeline Safety.”
INGAA. INGAA Foundation, Inc., 8 Nov. 2012. Web. 21 Apr. 2016.
Kocher, Greg. “Pipeline Would Carry Natural Gas Liquids through 18 Kentucky Counties
under Controversial Plan.” Marcellus. The Lexington Herald-Leader, 2015. Web. 23
Apr. 2016.
Krebs, Charles J. The Ecological World View. Berkeley: University of California Press,
2008. Print.
Marek, R., Jr. “Job Report: Bio-assay and Chemical Analysis of Jefferson Chemical, Texas-
U.S. Chemical Goodrich Gulf, and Neches Butane Waste Waters, Port Neches, Texas.”
Texas Digital Library Repositories. Texas Game and Fish Commission, n.d. Web. 21
Apr. 2016.
Miles, Preston. Personal Interview. 24 Apr. 2016.
Patin, Stanislav. “Natural Gas in the Marine Environment.” Offshore-Environment.
EcoMonitor Publishing, n.d. Web. 23 Apr. 2016.
“The Utica Marcellus Texas Pipeline Project.” Kentuckians for the Commonwealth. N.p.,
2016. Web. 23 Apr. 2016.
“White Bass.” Office for Environmental Programs Outreach Services. University of
Kentucky, 1 Apr. 2016. Web. 23 Apr. 2016.