2016-05-13 Parette Expert Report- Mayo Site - 05-13-16

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MATSON
ASSOCIATES
Opinions on the Appropriateness of Monitored Natural Attenuation
in Conjunction with Cap -in -Place at the Mayo Steam Station,
Roxboro, NC
Prepared for:
Southern Environmental Law Center
22 South Pack Square, Suite 700
Asheville, NC 28801
Prepared by:
Robert Parette, Ph.D., P.E.
May 13, 2016

Table of Contents
I. Qualifications...................................................................................................................................1
11. Scope of Wo k.................................................................................................................................1
III. Basis of Opinion...........................................................................................................................1
IV. Methodology...............................................................................................................................1
V. Backg ound.....................................................................................................................................3
A. Coal Ash and the Mayo Site.......................................................................................................... 3
B. Monito ed Natu al Attenuation (MNA)........................................................................................4
VI. Opinion: Monito ed Natu al Attenuation is not an app op iate emedy at the Mayo site ............. 7
A. Evidence indicates that constituents in the g oundwate a e not being attenuated by adso ption
uncle cu ent conditions at the Mayo site...........................................................................................7
B. Kd values dete mined in the labo ato y cannot be eliably utilized as a means to demonst ate
site-specific attenuation fo the Mayo site...........................................................................................8
C. When MNA is based upon adso ption of COls onto i on and manganese oxides, the utilization of
MNA in combination with capping is p oblematic as conditions fo MNA a e less favo able following
capping................................................................................................................................................ 9
D. MNA based upon adso ption is not an app op iate emedy fo a senic at the Mayo site ............ 10
VII. Refe ences.................................................................................................................................12

I. Qual f cat ons
I am an Envi onmental Enginee (P.E.) at Matson & Associates, Inc. (M&A). My academic
backg ound includes a B.S. in Chemical Enginee ing f om Wo ceste Polytechnic Institute and a
M.S. and a Ph.D. in Envi onmental Enginee ing f om The Pennsylvania State Unive sity. I have
ove 10 yea s of expe ience in the emoval of va ious contaminants f om envi onmental media.
I have co-autho ed seve al pee - eviewed pape s pe taining to the emoval of a senic f om
g oundwate utilizing i on o i on-tailo ed adso bents. I have also p eviously evaluated
emedies fo a senic contaminated g oundwate (including MNA) at coal ash disposal sites, as
well as the use of va ious technologies to t eat effluent impacted by metals and othe
constituents at a coal mining site. My CV is attached in Appendix A.
II. Scope of Work
I was etained by the Southe n Envi onmental Law Cente (SELC) to evaluate whethe
Monito ed Natu al Attenuation (MNA), in conjunction with Cap -in -Place, is an app op iate
emedy fo Duke's Mayo Steam Station (Mayo site) nea Roxbo o, NC.
III. Bas s of Op n on
My opinion is based on site specific documents, as well as scientific lite atu e, and my education
and expe ience. My opinion is based on a easonable deg ee of enginee ing and scientific
ce tainty. I ese ve the ight to supplement my opinions should additional info mation become
available.
IV. Methodology
My ole in this matte was to evaluate whethe MNA, in conjunction with Cap -in -Place, is an
app op iate emedy fo the Mayo site. An evaluation of the app op iateness of MNA at a site
equi es an in-depth uncle standing of the p ocesses that constitute natu al attenuation at the
site and how the site specific envi onmental conditions impact these p ocesses. Fo the Mayo
site, knowing the constituents of inte est (COls) and that the emedial st ategy p oposed by
Duke Ene gy was based in -pa t on co -p ecipitation and adso ption, I evaluated whethe these
p ocesses we a occu ing uncle the specific conditions found at the Mayo site. My evaluation
utilized the c ite is established by the U.S. EPA fo MNA of ino ganic contaminants in
g oundwate ; the same c ite is identified by Duke's consultants in thei analysis.
My opinions a e based on conside ation of data and info mation p ovided in the Comp ehensive
Site Assessment Repo t, the Co ective Action Plan Pa t 1, and the Co ective Action Plan Pa t 2
fo the Mayo site; and on methods that I have used in othe scientific o enginee ing inqui ies
conce ning envi onmental p ocesses, which a e based upon methods and analysis widely
accepted in the published, pee - eviewed lite atu a in the fields of envi onmental science and
enginee ing. Fi st, I examine the data available to dete mine whethe a p ocess is wo king, and
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if not I then conduct esea ch to dete mine why. This esea ch gene ally involves a eview of
the elevant pee - eviewed lite atu e followed by an analysis of the applicability of the lite atu e
to the p ocess being evaluated.
In this matte I examined all of the available data fo the coal ash, the g oundwate , and the
solid-wate pai analyses to gain an uncle standing as to whethe COls we e natu ally
attenuating and to gain an uncle standing of the site conditions influencing natu al attenuation.
I then conducted a lite atu a sea ch fo studies on simila MNA applications. Since the
application of MNA as a t eatment fo COls in g oundwate at coal ash sites is new, published
lite atu a on sites whe e it has been implemented fo such pu pose is not yet available fo
assessment of MNA's pe fo mance in this capacity. The efo e, I eviewed a numbe of studies in
the pee - eviewed lite atu a that had examined the effectiveness of t eating coal ash leachate
o individual COls in othe systems with i on o manganese oxides in active o enginee ed
t eatment systems. These studies included my own publications investigating how i on and
a senic behave in g oundwate t eatment ope ations in o de to design effective t eatment
systems fo a senic emoval. Based on my knowledge, t aining, education, and yea s of
expe ience esea ching emoval by adso ption onto i on oxides, I knew that a numbe of facto s
can influence the adso ption of COls to metal oxides so I conducted an investigation to
dete mine whethe the Mayo site conditions we a impacting MNA.
My ole also involved evaluating the effectiveness of MNA uncle Duke's p oposed plan of
capping the Mayo site. The efo e, I conducted a simila analysis of MNA uncle alte ed site
conditions based on this p oposed scena io.
My analysis focused on a numbe of COls as identified in my opinion below in Section VI. Fo the
COls not discussed, I am not making a dete mination on whethe MNA is an app op iate
emedy.
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V. Background
A. Coal Ash and the Mayo Site
• Coal ash is the waste mate ial p oduced f om the bu ning of coal in coal-fi ed powe
plants. It is comp ised of a numbe of byp oducts. Fo example, fly ash is "a ve y fine
powde y mate ial comp ised mostly of silica made f om the bu ning of finely g ound
coal in a boile ." (U.S. EPA 2016). Bottom ash, is aptly named fo the ash pa ticles
that a e too la ge to be ca ied into the smoke stacks and thus collect in the bottom
of the boile (U.S. EPA 2016). Both p oducts a e commonly efe ed to as coal ash.
• Coal ash in gene al is comp ised mainly of oxides of silica, aluminum, i on and
calcium, and also contains nume ous othe elements such as a senic, bo on,
ch omium, cobalt, and vanadium. Exposu a of coal ash to wate is known to cause
the leaching and elease of coal ash constituents to g oundwate and su face wate
(Elect is Powe Resea ch Institute 2009, Liu et al. 2004, Lokeshappa et al. 2014,
Abe nethy et al. 1969).
• The Mayo Steam Station (Mayo site) is located nea the weste n bank of the Mayo
Lake, nea Roxbo o, No th Ca olina. Beginning in 1983 coal was bu ned at the site
to p oduce elect icity. (Co ective Action Plan Pa t 1, Appendix Q.
• At the Mayo site coal combustion esiduals we a disposed into an ash basin
occupying app oximately 144 ac es. The basin was c eated by impounding
C utchfield B anch, a small st eam that flows to the no th, th ough the const uction
of a 2,300 foot long ea then dam with a height of 110 feet. The ash basin (the
fo me st eam valley of C utchfield B anch), is app oximately half open wate and
half ash (as shown in Figu a ES -2 of the Co ective Action Plan Pa t 2). (Co ective
Action Plan Pa t 1, Appendix Q. Acco ding to Duke's website, the "total volume of
ash" at the Mayo site is 6.51 million tons (Duke Ene gy Ash Met ics).
• A small st eam flows into the Mayo site ash basin. Based on the wate elevation in
the ash basin (in compa ison to the elevation in wells along C utchfield B anch
(no th of the basin), Duke indicated that g oundwate gene ally flows no th-
no theast f om the ash basin, but also that site g oundwate f om the easte n side
of the site discha ges to Mayo Lake (Comp ehensive Site Assessment Repo t,
Co ective Action Plan Pa t 1 Appendix Q.
• Coal ash disposal at the Mayo site has led to a numbe of constituents in site
g oundwate that exceed applicable standa ds. Based on the Co ective Action Plan
Pa t 1, these constituents a e antimony, a senic, ba ium, bo on, ch omium, cobalt,
i on, manganese, thallium, total dissolved solids (TDS), and vanadium. These
g oundwate constituents, he ein efe ed to as constituents of inte est (COls), will
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t avel with the g oundwate unless they a e emoved (adso bed, p ecipitated, etc.)
along the g oundwate flow path.
• Duke has p oposed to utilize cap -in-place in combination with monito ed natu al
attenuation at the Mayo site. Duke indicates that cap -in-place at the Mayo site will
place "a low pe meable line ove the ash basin to contain the ash and p event
ainwate infilt ation" (Co ective Action Plan Pa t 1 Appendix Q.
B. Monito ed Natu al Attenuation (MNA)
• MNA elies solely on natu al envi onmental geochemical p ocesses to mitigate
concent ations of contaminants (no active emediation) with egula ly scheduled
monito ing to assess whethe MNA is wo king. Acco ding to the USEPA (2012):
"Monito ing typically involves collecting soil and g oundwate samples to
analyze them" fo the contaminants of conce n and othe site pa amete s. The
" ight conditions must exist uncle g ound to clean sites p ope ly and quickly
enough."
• COls at the Mayo site a e elements (ino ganics), and the efo a cannot be dest oyed.
Natu al p ocesses to immobilize ino ganics include adso ption, p ecipitation/co-
p ecipitation, and/o oxidation- eduction eactions (U.S. EPA 2007a). Duke
indicated that at the Mayo site, that "attenuation is in the fo m of dilution as
constituents flow th ough the system; so ption whe eby aqueous ions a e emoved
by chemical inte actions with a su face [adso ption]; and chemical p ecipitation
which includes homogeneous mine al p ecipitation and co -p ecipitation"
(Co ective Action Plan Pa t 2). P ocesses such as adso ption and co -p ecipitation
can potentially immobilize a COI, and evaluating the effectiveness of natu al
attenuation via these p ocesses is the focus of this epo t. While concent ations of
COls can be educed via dilution, dilution does not p event the movement o
discha ge of a COI f om a site.
• Duke is elying in -pa t upon adso ption/co-p ecipitation of COls onto hyd ous metal
oxides, such as i on and manganese in its selection of MNA as a emedy. In educed
fo ms (i on and manganese in the +2 oxidation state), i on and manganese (also
components of coal ash) have highe solubility and mobility. As these species
mig ate f om thei sou ce and encounte mo a oxidized conditions, p ecipitation
(pa ticula ly fo i on) as insoluble species (i on in the +3 oxidation state and
manganese in the +4 oxidation state) occu s c eating su faces onto which COls can
be adso bed. MNA based on these p ocesses is successful only uncle the ight
conditions, which will be discussed in mo a detail below.
• In gene al, many g oundwate constituents a e known to adso b onto i on oxide
su faces. In gene al, adso ption of g oundwate constituents onto manganese oxide
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su faces is not as well studied, though it is known that manganese oxide is not an
effective adso bent fo a senic, but has been epo ted to have high affinity fo
cobaltuncle the ight conditions (Hoffman et al. 2006, Salminen 2005).
• In gene al, the e a e a numbe of facto s that influence the effectiveness of natu al
attenuation fo ino ganics at a site. These facto s include (but a e not limited to)
the oxidation- eduction potential of the g oundwate , the pH, competition fo
adso ption sites, complexation, the elative ates of oxidation between a COI and a
potential adso bent such as i on, the amount of COls in the coal ash sou ce, and
atios of COls to adso bents.
o The speciation of a COI is dependent upon pH and the oxidation- eduction
potential of the g oundwate . Potential emoval mechanisms fo a constituent
can change depending upon the speciation of the constituent.
o In addition to COls having to compete against each othe fo adso ption sites,
othe constituents p esent in the g oundwate can also significantly impact the
adso ption of COls onto hyd ous metal oxide su faces. Fo example, silica,
phosphate, bica bonate, and dissolved o ganic ca bon can p esent competition
p oblems (Meng et al. 2002, Meng et al. 2000, Holm et al. 2008, Su and Puls
2003, Holm 2002, Mille 2001, Swedlund and Webste 1999, Chen et al. 2007,
Sa ka et al. 2014, Ma iussen et al. 2015, U.S. EPA 2007b). Based on my eview
of site data, to my knowledge, concent ations of silica and phosphate in Mayo
site g ound g oundwate have not been monito ed.
■ G oundwate typically contains silica in the ange of 3.3 to 21 mg/L (as Si)
(Holm et al. 2008, Davis et al. 2001). Silica is known to limit the adso ption
of COls onto i on oxides (Meng et al. 2000, Davis et al. 2001, Swedlund and
Webste 1999). Dissolved silica at concent ations below the typical ange
found in g oundwate has been shown to limit adso ption of the COls
(Mille 2001). Silica comp ises a majo f action of coal ash by weight
(Elect is Powe Resea ch Institute 2009), and has been found in the
g oundwate between 180 and 650 mg/L as Si at a coal ash site in the mid-
Atlantic egion.
■ Concent ations of phosphate below 1 mg/L have been shown to limit
adso ption of COls. The p esence of silica is known to magnify the impact of
phosphate. Phospho us pentaoxide (which fo ms phosphate in wate ) is a
known constituent of coal ash (Meng et al. 2002, Meng et al. 2000, Holm et
al. 2008, Su and Puls 2003, Holm 2002, Blackmo a et al. 1996, Liu et al.
2004).
■ With ega d to cobalt adso ption onto manganese oxide, othe metals such
as coppe , nickel, and zinc may outcompete it fo adso ption sites
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(Mukhe jee et al. 2013). The p esence of bo ate (bo on is a site COI) can
also significantly educe the adso ption of cobalt onto manganese oxides
(Hasany and Qu eshi 1981).
o Othe constituents in g oundwate can fo m complexes with metals which can
dec ease COI adso ption/co-p ecipitation. Fo example, vanadium, a site COI,
can fo m complexes with sulfate (Salminen 2005, U.S. EPA 2007a).
o When utilizing i on to emove COls such as a senic and vanadium, oxidation of
these ino ganics should occu simultaneously with the oxidation of i on to
achieve optimal emoval (Hoffman et al. 2006, Rocca o and Vagliasindi 2015).
• Due to the numbe of va iables that can impact MNA of ino ganics, the feasibility of
utilizing natu al attenuation fo ino ganics must be assessed on a site -by -site basis
because the effectiveness is highly site specific (Reisinge et al. 2005, Mille 2011).
• Acco ding to the U.S. EPA, dete mining the feasibility of using MNA at a site fo an
ino ganic constituent at a site is a fou -tie ed evaluation (U.S. EPA 2007a).
• The envi onmental geochemical p ocesses that constitute natu al attenuation fo
COls at the Mayo site a e ongoing, and have been ongoing since coal ash disposal
began; these p ocesses do not begin at the time MNA is app oved as a emedy fo a
site. The efo e, a Tie I evaluation establishes whethe natu al attenuation is
cu ently occu ing at the site, and if so is the fi st step in demonst ating the long
to m app op iateness of MNA as a site emedy.
• In the Tie I evaluation p ocess, concent ations of COls we a measu ed in Mayo site
wate and soil (solid) f om the same location and depth. If attenuation is occu ing
via adso ption onto aquife solids, the concent ation of the COI on the solid mate ial
should inc ease with the concent ation of the COI in the g oundwate . An example
of this type of analysis is shown below in Figu e 1 (U.S. EPA 2007a). A st ong
positive co elation between the COI concent ation in wate and solid pai s
indicates attenuation. Conve sely, acco ding to the U.S. EPA, sites whe e COI
attenuation is not obse ved "would be eliminated f om fu the conside ation of
MNA as pa t of the cleanup emedy" (U.S. EPA 2007a).
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F gure 1. Example of a sol d -water pa r analys s to
demonstrate attenuat on (adapted from U.S. EPA 2007a)
Site -Specific
Sorption Trend
(A)
AttenuationAttenuation
(B)
NoNo Attenuation
Arpuaos (Ppm)
• Simila to the elationship analysis shown in Figu e 1, a p opo tionality constant (Kd)
can be dete mined in the labo ato y by allowing site soil samples to equilib ate with
wate . Kd is defined as the concent ation of the COI in the solid divided by the
concent ation of the COI dissolved in the wate . In a solid-wate pai analysis with a
positive linea t end, Kd would be the slope of the t end line. Kd values can give an
indication of the potential fo dissolved COIs in g oundwate to adso b onto soil,
which then can be elated to the ate at which a COI moves in elation to the ate of
g oundwate movement (Co ective Action Plan Pa t 1 Appendix D).
• With ega d to the Mayo site, Duke also pe fo med geochemical modeling
(Co ective Action Plan Pa t 2). The U.S. EPA ecommended that modeling esults
be "used as seconda y lines of evidence in suppo t of site-specific measu ements
that demonst ate active so ption of the contaminant onto aquife solids" and not be
elied upon independently (U.S. EPA 2007a).
VI. Op n on: Mon tored Natural Attenuat on s not an appropr ate remedy at the Mayo
s te.
A. Evidence indicates that constituents in the g oundwate a e not being attenuated by adso ption
uncle cu ent conditions at the Mavo site
• Duke pe fo med a solid-wate pai analysis fo five COls that have been measu ed in
Mayo site wells at concent ations that have exceeded applicable standa ds. These
COls we e a senic, bo on, ch omium, i on, and manganese.
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• In its analysis, Duke stated that examination of the solid-wate pai s " eveals that
little so ption appea s to be occu ing at Mayo", "likely because g oundwate flow is
la gely th ough the t ansition zone and uppe bed ock units, whe e thei physical
p ope ties limit the amount of adso ption."
• The t end line fo the solid-wate pai analysis fo each of these COls has a negative
slope. Adso ption onto solids is not inc easing as a function of the g oundwate
concent ation, as would be the case if attenuation was occu ing via adso ption (as
shown in Figu e 1 above f om U.S. EPA 2007a).
• Fu the mo e, g oundwate will continue to flow th ough the t ansition zone and
uppe bed ock units (as shown in Figu a ES -2 of the Co ective Action Plan Pa t 1),
(even if the ash is capped in place). The efo e, the "physical p ope ties that limit
the amount of adso ption" in the t ansition zone and uppe bed ock is a pe manent
p oblem.
• In gene al, it is uncle stood that bo on is poo ly adso bed.
o Results of the labo ato y soil so ption expe iments indicate that "bo on so ption
is ve y low in Mayo site soil samples" (Co ective Action Plan Pa t 1 Appendix D).
o With ega d to coal combustion p oduct leachate, MNA pathways do not exist
fo bo on (Mille 2011).
o Bo on was not effectively emoved f om coal ash leachate by adso ption/co-
p ecipitation with i on in a settling basin at a site in Pennsylvania (Rightnou and
Hoove 1998).
B. Kd values dete mined in the labo ato v cannot be eliably utilized as a means to demonst ate
site-specific attenuation fo the Mayo site.
• Kd values dete mined in the labo ato y a e not ep esentative of site-specific Kd
values fo the Mayo site. As stated above, Kd is a pa amete to estimate the
potential fo the adso ption of the COls in the g oundwate onto soil. Fo the Mayo
site, Kd values we a dete mined expe imentally in the labo ato y using "synthetic
g oundwate ", which was ve y limited in to ms of the numbe of constituents and in
many cases the concent ation of these constituents, and the efo a was not
ep esentative of g oundwate impacted by coal ash at the Mayo site.
o Duke, in the Co ective Action Plan Pa t 1 (Appendix D) states that "a solution
intended to ep esent ae� ne is g oundwate is used as the backg ound to
which [contaminants of conce n] we a added" and that "this solution diffe s
f om the actual solution in g oundwate f om which the soil sample was
sample[d]".
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• The Kd expe iments we a conducted uncle oxic (high oxygen) conditions. In
Co ective Action Plan Pa t 2 epo is fo othe sites (Allen, Belews C eek, Buck,
Cliffside, Ma shall), Duke stated that "typically Kd expe iments a e also conducted
uncle oxic [high oxygen] conditions, which may not eflect actual site conditions.
Consequently, Kd values f om labo ato y expe iments should be inte p eted and
used with caution because they may not account fo the full ange of so ption
conditions that occu in hete ogeneous, natu al soils."
• Additionally, the "synthetic g oundwate " did not include a numbe of competing
constituents that a e known to limit adso ption of COls. These include silica and
phosphate, which can significantly impact adso ption. Silica, in pa ticula , can be
p esent at ve y high concent ations at coal ash disposal sites.
• The efo e, the Kd values dete mined in the labo ato y we e likely biased high
because the "synthetic g oundwate " did not have othe constituents competing fo
the same adso ption sites.
C. When MNA is based upon adso ption of COls onto i on and manganese oxides, the utilization of
MNA in combination with capping is p oblematic as conditions fo MNA a e less favo able
following capping.
• Even if the site is capped, much of the coal ash at the Mayo site will emain in
contact with g oundwate (Co ective Action Plan Pa t 1 Appendix E, Figu es 16 and
17a). This means that Cols can continue to leach f om the coal ash.
• Reducing infilt ation will educe the echa ge of oxygen into site g oundwate and
likely c eate mo a anoxic (less oxygen) conditions in the site g oundwate , which
can impact the mobility of constituents in the g oundwate (Schwa tz et al. 2016).
• The solubility of i on and manganese is st ongly influenced by oxidation- eduction
potential conditions, with solubility inc easing as the oxidation- eduction potential
is dec eased. Both a e eadily mobilized o esolubilized uncle anoxic conditions.
COls that had p eviously adso bed to i on o manganese will be emobilized and
potentially lead to a slug of COls ente ing the g oundwate . When i on and
manganese a e in the dissolved phase, COls cannot adso b to them. (Salminen
2005, Masscheleyn et al. 1991, Ha to et al. 2012, Schwa tz et al. 2016, U.S. EPA
2007b, Ta utis and Unz 1995).
• Though i on is eadily oxidized when it comes into contact with oxygen, ae ation
(oxygen) is not effective fo oxidizing dissolved manganese (manganese in the +2
oxidation state) to the elatively insoluble +4 oxidation state. The efo e d inking
wate t eatment plants utilize a st ong oxidant such as ozone, chlo ine dioxide, o
potassium pe manganate when manganese emoval is equi ed. Additionally, the
p esence of dissolved i on in the g oundwate inhibits the fo mation of manganese
O7

oxides. Only 14% manganese emoval was obse ved in a settling basin following
ae ation used to t eat coal ash leachate at a site in Pennsylvania (Hoffman et al.
2006, Ta utis and Unz 1995, Robinson -Lo a and B ennan 2011, Rightnou and
Hoove 1998). This is impo tant because the fo mation of manganese oxides has
been identified as a COI at the Mayo site.
• Infilt ation (and thus oxygen echa ge) would be educed ove the a ea of the Mayo
site uncle the cap, and thus i on and manganese mobility will be enhanced (less
i on and manganese oxide p ecipitation/COI adso ption occu ing within the a ea
that is capped). This inhe ently sho tens the distance to the site bounda y ove
which these MNA p ocesses can potentially occu .
D. MNA based upon adso ption is not an app op iate emedy fo a senic at the Mayo site.
• MNA fo a senic was not obse ved in the soil-wate pai analysis conducted by Duke
fo the Mayo site. The t end line had a dec easing slope. If attenuation was
obse ved, a positive co elation (positive slope) between a senic concent ation in
the wate phase and the solid phase (as shown in Figu e 1 above) should have been
obse ved.
• A senic in wate is typically p esent in the +3 oxidation state [As(III)] o the +5
oxidation state depending the oxidation- eduction potential (oxygen concent ation)
of the g oundwate . As(III) is favo ed uncle educed (low oxygen) conditions and
As(V) is favo ed uncle oxidized conditions. Compa ed to As(V), As(III) is mo a toxic,
mo a soluble, and mo e difficult to adso b (e.g. mo a mobile). The efo e the
leaching and mobility of a senic gene ally inc eases as edox potential dec eases
(Schwa tz et al. 2016, Ha to et al. 2012, Masscheleyn et al. 1991). Duke
uncle stands that a senic is gene ally less mobile uncle oxidizing conditions
(Co ective Action Plan Pa t 2 Appendix C).
• Fo a senic in g oundwate at the Mayo site, As(III) is the p edominant species of
a senic measu ed in site g oundwate samples (Co ective Action Plan Pa t 2
Appendix C).
• Capping the site will make conditions less favo able fo MNA of a senic. Capping of
the site will lead to mo a anoxic conditions in the site g oundwate (Schwa tz et al.
2016), which would likely lead to an inc ease in the atio of As(III) to As(V); thus the
addition of a cap would likely inc ease the mobility of a senic at the Mayo site.
• Conce n ove a eduction in site g oundwate oxidation- eduction potential and
enhancement of a senic solubility as a esult of closu a plans fo coal ash
impoundments that include capping, led a g oup of scientists to ecently state that
"even if no p evious g oundwate contamination issues have been epo ted,
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capping methods that might induce anae obic conditions should be avoided in the
closu a of unlined impoundments" (Schwa tz et al. 2016).
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VII. References
Abe nethy, RF; MJ Pete son and FH Gibson (1969). Spect ochemical analyses of coal ash fo t ace
elements. United States Depa tment of the Inte io , Repo t of Investigations 7281.
Blackmo e, DPT; J Ellis and PJ Riley (1996). T eatment of a vanadium -containing effluent by
adso ption/cop ecipitation with i on oxyhyd oxide. Wate Resea ch 30(10): 2512-6.
Chen, W; R Pa ette, J Zou, FS Cannon and BA Dempsey (2007). A senic emoval by i on modified
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14

APPENDIX A
D . Robe t Pa ette CV
15

ROBERT PARETTE
Matson & Assoc ates, Inc.
331 East Foster Avenue, State College, PA 16801
Phone: [phone] Ema I: bparette@matson-assoc ates.com
EDUCATIO
Doctor of Philosophy August 2005
Env ronmental Eng neer ng
The Pennsylvan a State Un vers ty, Un vers ty Park, PA
D ssertat on: The Removal of Perchlorate from Groundwater v a Quaternary
Ammon um Cat on c Surfactant Pre -Loaded GAC
Master of Science May 2004
Env ronmental Eng neer ng
The Pennsylvan a State Un vers ty, Un vers ty Park, PA
Thes s: GAC Ta lored w th Organ c Cat ons for the Removal of Perchlorate from
Groundwater and Base/Ac d Chem cal Regenerat on of the GAC
Bachelor of Science February 1999
Chem cal Eng neer ng
Worcester Polytechn c Inst tute, Worcester, MA
WORK EXPERIE CE
Matson and Associates, Inc., State College, PA
Env ronmental Eng neer (P.E.)/Env ronmental Chem st (2009-2014)
V ce Pres dent of Eng neer ng/Project Manager for Matson B ofuels (2009-2011)
The Pennsylvania State University, Dept. of Civil and Environmental Engineering
Post -Doctoral Research Assoc ate (2005-2009)
Graduate Research Ass stant (2000-2005)
Environmental Consultant
Ass stant to Penn State professor sery ng as an expert w tness (2007)
Hercules Incorporated Research Center, Wilmington, DE
Research Ass stant (1998)
REPRESE TATIVE PROJECT EXPERIE CE
• Rev ewed closure plan alternat ves for a coal ash mpoundment located n Conway, South
Carol na. Prepared wr tten comments address ng the lack of groundwater treatment (as part of
these closure plan alternat ves) and the feas b I ty of remed at ng the arsen c contam nated
groundwater.
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• Evaluated the d sposal pract ces of waste salt conta n ng arsen c at a fac I ty along the
Menom nee R ver n W scons n n relat on to waste d sposal standards and the alternat ve
d sposal opt ons ava fable. Invest gated the spec at on of arsen c n the waste salts, the
propert es of the var ous arsen c spec es, and the transformat ons these arsen c spec es would
undergo n the env ronment.
• At Penn State, 9% years of R&D on technolog es to remed ate ground water. Th s R&D resulted
n numerous publ cat ons (I sted below) on the removal of arsen c and perchlorate from water.
Des gned and produced custom adsorbents for the removal of arsen c from groundwater.
Des gned and fabr cated a p lot plant w th a capac ty n excess of one m II on gallons per year to
study the removal of arsen c by a comb nat on of act vated carbon and ron from a var ety of
d fferent sources. Respons ble for develop ng exper mental and sampl ng plans for a number of
p lot and laboratory stud es.
• Evaluated treatment technolog es, and the feas b I ty of employ ng such technolog es, n
connect on w th remed at ng a large lake contam nated w th selen um. Prepared a report to be
ut I zed for publ c comments and negot at ons w th the power company.
• Evaluated the potent al mplementat on of var ous technolog es for a number of outfalls at a
coal m n ng operat on n western Pennsylvan a. Prepared wr tten comments address ng
shortcom ngs of a consent decree perta n ng to the s te.
• Evaluated wastewater treatment pract ces of a paper m II along the Fox R ver n W scons n n
relat on to the treatment opt ons ava fable (chronolog cally) to the pulp and paper ndustry and
the removal eff c enc es ach eved by var ous treatment technolog es across the ndustry.
• Des gned and conducted laboratory exper ments to test the mpact of MTBE on the removal of
other organ c contam nants from groundwater for a case nvolv ng MTBE n Suffolk County, NY.
Ut I zed mult ple f eld data sets to assess the ab I ty of act vated carbon to remove MTBE,
ass sted n the preparat on of expert w tness reports, and performed an extens ve I terature
rev ew pert nent to the case.
• Correlated s to act v t es at an abandoned chem cal manufactur ng plant n NJ w th
contam nants found n the near offshore areas of the s te; determ ned the or g n and chem cal
react ons beh nd the presence of 2,4,6,8-tetrachlorod benzoth ophene (2,4,6,8-TCDT), a
contam nant whose source was prev ously unknown.
• Evaluated the s ngle phase eff c ency for the str pp ng of CO2 n a cool ng tower model for an
nternat onal company that spec al zes n gases. Mod f ed the model's source code to reflect the
determ ned s ngle stage eff c ency, evaluated the I qu d to gas rat o ut I zed by the model, and
compared results from the model aga nst the exper mental data.
• Invest gated groundwater qual ty and consulted w th a forester at a res dent al s to n Centre
County, PA, mpacted by a nearby hous ng development.
• D rected the R&D efforts for Matson B ofuels from 2009 through 2011. Respons ble for the
management of three b od esel projects, w th grant fund ng n excess of $250K. Developed sol d
A-2

catalysts capable of convert ng low qual ty o I feedstocks to b od esel w th no feedstock
pretreatment and no soap format on. Des gned a p lot plant, w th a capac ty to produce more
than 1 m II on gallons of b od esel annually.
PUBLICATIO 5
R Parette, R McCr ndle, KS McMahon, M Pena-Abaurrea, E Re ner, B Ch tt m, N R ddell, G Voss, FL
Dorman, WN Pearson and M Robson (2016). Response to the comment on "Halogenated nd go dyes
I kely source of 1,3,6,8-tetrabromocarbazole and some other halogenated carbazoles n the
env ronment". Chemosphere 150: 414-5.
N R ddell, UH J n, S Safe, Y Cheng, B Ch tt m, A Konstant nov, R Parette, M Pena-Abaurrea, EJ Re ner, D
Po r er, T Stefanac, AJ McAlees and R McCr ndle (2015). Character zat on and b olog cal potency of
mono- to tetra -halogenated carbazoles. Env ronmental Sc ence & Technology 49 (17): 10658-66.
R Parette, R McCr ndle, KS McMahon, M Pena-Abaurrea, E Re ner, B Ch tt m, N R ddell, G Voss, FL
Dorman and WN Pearson (2015). Halogenated nd go dyes: a I kely source of 1,3,6,8-
tetrabromocarbazole and some other halogenated carbazoles n the env ronment. Chemosphere 127:
18-26.
R Parette and WN Pearson (2014). 2,4,6,8-Tetrachlorod benzoth ophene n the Newark Bay Estuary: the
I kely source and react on pathways. Chemosphere 111: 157-63.
W Chen, R Parette and FS Cannon (2012). P lot -scale stud es of arsen c removal w th granular act vated
carbon and zero -valent ron. Env ronmental Eng neer ng Sc ence 29(9): 897-901.
K Gombotz, R Parette, G Aust c, D Kannan and J Matson (2012). MnO and T O sol d catalysts w th low-
grade feedstocks for b od esel product on. Fuel 92(1): 9-15.
MK Sel em, S Komarnen, R Parette, H Katsuk, FS Cannon, MG Shah en, AA Khal I and IM Abdel -Ga d
(2011). Perchlorate uptake by organos I cas, organo -clay m nerals and compos tes of r ce husk w th
MCM-48. Appl ed Clay Sc ence 53: 621-6.
JP Patterson, R Parette and FS Cannon (2011). Compet t on of an ons w th perchlorate for exchange s tes
on cat on c surfactant-ta lored GAC. Env ronmental Eng neer ng Sc ence 28(4): 249-56.
JY K m, S Komarnen , R Parette and FS Cannon (2011). Perchlorate uptake by synthet c layered double
hydrox des and organoclays. Appl ed Clay Sc ence 51(1-2): 158-64.
JP Patterson, R Parette and FS Cannon (2010). Ox dat on of ntermed ate sulfur spec es (th osulfate) by
free chlor ne to ncrease the bed I fe of to lored GAC to remove perchlorate. Env ronmental Eng neer ng
Sc ence 27(10): 835-43.
MK Sel em, S Komarnen, R Parette, H Katsuk, FS Cannon, MG Shah en, AA Khal I and IM Abdel -Ga d
(2010). Compos tes of MCM-41 s I ca w th r ce husk: Hydrothermal Synthes s, character zat on and
appl cat on for perchlorate separat on. Mater als Research Innovat ons 14(5): 351-4.
A-3

S Komarnen , J Y K m, R Parette and FS Cannon (2010). As -Synthes zed MCM-41 s I ca: New adsorbent for
perchlorate. Journal of Porous Mater als 17: 651-6.
MJ Jang, FS Cannon, R Parette, S Yoon and W Chen (2009). Comb ned hydrous ferr c ox de and
quaternary ammon um surfactant to for ng of granular act vated carbon for concurrent arsen c and
perchlorate removal. Water Research 43(12): 3133-43.
W Chen, R Parette and FS Cannon FS (2008). Arsen c adsorpt on v a ron preloaded act vated carbon and
zero -valent ron. Journal of Amer can Water Works Assoc at on 100(8): 96-105.
W Chen, R Parette, J Zou, FS Cannon and BA Dempsey (2007). Arsen c removal by ron-mod f ed
act vated carbon. Water Research 41(9): 1851-8.
R Parette and FS Cannon (2006). Perchlorate removal by mod f ed act vated carbon. In Perchlorate
Env ronmental Occurrence, Chem stry, Tox cology, and Remed at on Technolog es. Spr nger Publ sh ng
Company, New York.
R Parette and FS Cannon (2005). The removal of perchlorate from groundwater by act vated carbon
to lored w th cat on c surfactants. Water Research 39(16): 4020-28.
R Parette, FS Cannon and K Weeks (2005). Remov ng low ppb level perchlorate, RDX, and HMX from
groundwater w th cetyltr methylammon um chlor de (CTAC) pre -loaded act vated carbon. Water
Research 39(19): 4683-92.
A-4