NCD980602163_19960924_Warren County PCB Landfill_SERB C_Response to Peer Review Comments-OCR

BF A Environmental Consultants
Barnes, Ferland and
MEMORANDUM
FAX ONLY -[phone]
TO:
FROM:
DATE:
Bill Meyer / ,?.--
Patrick Barnes ~r
September 24, 1996
SUBJECT: Response to Peer Review Comments
BFA#95-017
I have received the Peer review comments from S&ME and GEi. I am uncertain why we were
not made aware that comments would be forthcoming from individuals other than State staff In
your fax you ask for a response by today. Unfortunately, because of prior commitments that will
not be possible. I wiJI however try to fax you something by tomorrow.
P AB/psg,9-24BM 1. doc
The Hollister Building• 3535 Lawton Road• Suite 111 • Orlando. Florida 32803
Office [phone] • Fax (407} 896-1822
September 24~ 1996
To: Working Gtoup ......................................................................... by FAX
From: Joel Hirschhorn
Subject: State's peer review proce"
Today, Pat and I wer.e faxed copies of responses ftom two private engineering fums to
Bill Myer's office that represented a peer review of certain documents, primarily a submission by
Pat on the site investigation plan. My concerns are:
• Bill Myer did not inform Pat or mysel( nor the Working Group, that he was seeking
outside peer review on a very limited piece of work. I would b.ave found it more
appropriate to first complete the draft field sampling plan and then at the same time Pat
and I, and the Working Group, reviewed the draft to also send it out for external peer
review. Bill nuy be seeking a way to change and/or delay the site work.
■ The fact that Bill did this soon after the last meeting of the Working· Group, on Sept. 3,
and did oot inform us, undermines his stated explanations of why his office has not
completed a draft field sampling plan. His explanations are suspect and in.complete.
■ Th.e state manipulated the peer review process by its unilateral decisions about what it
gave the peer revieweJS and what kind of questions it wanted them to addtess. The
questions or issues were not given in writing, but may have been given informally.
• We have no way of knowing whcthe1 the firms supplying the peer reviews have business
relationships with the state, which seems likely, and, if so, have a conflict of interest. It
would be more appropriate to use e,q,erts with no such conflict, such as academics in the
state and private sector experts outside the state.
■ Because we did not know about "Miat the state was doing, we were placed in a position
where the state could have completely concealed its actions if it had received comments
that it did not like.
I recommend to the Working Group that .it formally adopt a policy on pc~ rC\iew of
documents that would:
• require the state to declare that it wants a peer review on a particular document
■ identify parties it intends to seek peer reviews from and certifies that there are oo plausible
conflicts ofinteJest for those parties, and gives an opportW11ty to us to identify others
• give an opportunity for the Science Advisors and Working Group to review any cover
letter that is used to identify what is desired of peer reviewers.
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TO:-:S
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i I I'* COVER SHEZ!r
PHONE! ----41-------
PHONE: 73.3• 996
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TOTAL NUMBER OF PAt.1£8 JNCl,UO~NCJ COVER SHEET: ~...--1-
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September 3, 1996
tJts. Ann Borden. Chairperson of the .
] Groundwater SubcomminN for the Professional
] Euglneen of North Carolina
clo S&M'E, lnc:.
3 ~ 00 Sprtna forest Road ·
Jyteigh, Nonh Carolina 27604
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l : rkar Ms.· Borden: 4. had t~od lote last woek abclll the pciss!bility or the Oroundwater Su mittee performilla
e peel' rc~iew of ~me of the groundwatet issues the State has with regard \o tht Wan-en County
PfB Lan~fill. Oµr Division Director, Mt. Bill Meyer discussed this with M . Don Carter of the
Ptofe11io~al Engineers of Nonh Carolina who offered the peer m'iew servi of this
a bcomn\iltee.
e Dtvi ·on staff had put toeether a workpJan (dated 4/26/95) <>utlining c
nitoring upgrades recommended for the Warren County landfill site. Thi
iewed by Mr. Cieor1c Bain, P. 0. who 'provlded comments in the fall of 1 95. In additjon, a
S pplcm~\al Site Investigation Plan was prepared (Summer 1996) by \he anen County
I dfill ~suhant Tbt scope of this peer review is to evaluate the reeom elations and
ndlusiohs in the State workplan, the comments provided by Mr. Bain and e site investigation
pl n prcpdred by the consultant. Attachment I to thia letter is a list of alt the ocuments included
F your peer review. lf'possfbJe. we would like to have the conclusions ofy ur peer review by
T ursday,: September J2, 1996. Please lei us know if this schedule i1 not co patibJc with your
w rk load.
ank yo~ for providing both your time and expertise to thi1 very important roject. We look
fo ard iq receivina your peer review results. If you have any queatiana pl feel free lo
c tacl n\t 8l (9J9) 733-2801 ·ext 236. :
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cc~ Bill Meyer
I P.0,9oX27687.
Sincerely,
Patridt Watters
Oivi1ion of Was
F~ l9-716-'61»
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elgh, North Caroloa 27611•7687
VolQe 9l9-7~
M f~Opport\lnl Afflrmotfve Actton Employer
S0\"9CVCltd/1 ~
woa.::1
r f\Ul1
'O"I . 41t" l -,.,.,
~ TTACHMENT I
Peer Review Document List
t'-Letter to Georce Bain, P.O. dated 917/9S v.:hich contains the 4/26195 Sta1 Workplan fol'
Ur,gradirlg the Oroundwater Monitoring-System at the Wamn Co1,111ty PCB Landfill alons with
O"e other references as noted in the 9n/95 letter.
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2~ LeUer to Geofie B11in, P. 0. dated 10/9/95 provjding suppJe1nen111l info ation es requested
~ Mr. Bain needed for his evaluation. ,
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3~ A rerits of chart, showina the aroundwater elevations taken from the 4 e istina n1onitorin1
~ells at the site ftom November 1992 throuah March I 995.
41 Letter fmm Oeorge Bain, P. G. dated f Oil 9195 documcnling the ,..vJu o hi• i--review,
5-PCB Landfill SuppJemmtel Site Jnve,tigation Plan prepared by Barnes. crland and
i•otiates, Inc. , Summer 1996.
5 d vlO~.:! l"l"tES : 0 96 6 l-17<:':-·G
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;Mr. Patrick Watters
;m.te Of North Caidlr)a . · · :
!DEHN" • DJvlelon of W.tte M1nao-m1nt
1P.o. Bo1< 21oe1 :
iR1letgh. North CeroUtia 27811•7887
Rlferenoe: Peer Rt¥lew of tht W1rren County PCI Landffll terf•1•
Dear Mr. Watter1:
Tho C!CIPENC Groundwater subciomm1ttee hu completed our nav..-of the referenced
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fnformlitlon provided to u.. We hid twa tlrmt of our committee be,-re1pond to our
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·J'9QU98t: S&M&. Inc. •nd GEi. Inc. iRath•r than combine the ntt by th••• ftrme, I ; . .
have etected to ettach their~ to thll letter. , I
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We apprecfett the opportunity to ptovfde peer rwvlew to you on th Important project. If
wt ce1ri be of further service, p~ can ue . .
i ' Slnoertly,
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Groundwater &ubcommrtt.. Chafr !
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t,1r. WNlltm Meyer · :
bk'edor, DMtlon of Weete Managtment
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Mr. Donald F. Carter, P.e. ; .
CECIPENC Envlronmentar dommlttM
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H'v'ES '0 966l-l70-C:
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l Sept~mber 20. 1eee
Me. A,ln M. Borden ·
S&Mij, Inc. :
· 3100 Spring Forw■t Ptoad
. R■lelgh, North Carolina 27818
V, • •-. I • ., , Y
Reference; Review of Warren qoumy PCB Landftll groundw r ... u,1
Dear Ann:
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A review of the Information that the· State hie provtdtd hat lead to • following comrnenta
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= and recommtndattont on the pro ••
' I NOTES FROM REVl&W OF WA~REN COUNTY LAN,DFILL PR 8AL8
1 COMMENTS:
1. Drawings In Packet~ thow monltorlng well MW-1 off
poulbly et the very heed of , twale. The BFA fig
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about ,on the rtdgiHnt. The actual location
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Interpretation of ni.t~ng and future ground-water da
potentlOmetrlc 1ulfl~.
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r of the rldgellne,
1how the well Just
Id enngly .«eat
· 2. The m~etung re1u(Ja In Paoktt #3 are clearty not raprnentatlv• of the
potentbmllCrlc 1urfac, due to lntufflcltnt date polntl. monitoring wel M'N-
. t ' 1 Is Indeed off~r, of the rld;ellne and nnr the he of a awale, much of
Ul• apparent lncontlttengy of the data could be exp lned. ' .
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S&M£. tnc. ~100 ,SprlnQ FQ!ff l\ood. ~~ Nc,nt, Co!cllrc 27604, (919) &72·2fJ60. F (919) 7Q0.9&27
Molll\Q ~P.O.~~-~~ Nonh Coron,~ 27638
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rf"ll\,lt l 7•.l't •J..J UIJ.J -•UL i V W"JIL,. "'""
: Ms. Ar,n M. Borden ·
: Septembef 20, 1996.
3. DSWM'1 proposal la to lnttan d"p well• to pair up 1hellow wella MW-2 . . .
and M'#-3, and to lnltatl. two other wen palrt on the n r1hea1t of the landflft,
I very ctoee to the 1d91 of th• landftll. Believe that th deep well• at MW-2
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and MW-3 are m•rit,d and wlll be needed but the tlon of the new well
pal11 puts too much ~ce on the exllttng landftl pping. Groundwater
flow. particularly 1haAow, around the landflll needl to be better deftntd,
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4. Georgtt Baln'a comrt'9nte are that the four mdlttng fie et the ett• appe11r
to be functioning pr~lti •nd that groundwater flo needs to be better
. I dtftned . both laterally end verttciHy. He tuggeetl • deep well at MW-4
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and three upgradlent ,hallow wells upgradlent of tt.t atte. H• refe,. to •
Figure 1 and a Svtrdrop and.PLl'C8II drawing whloh a not In the packet IO
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don't know exactly wtjere he hll In mind. Bain 1ugg te eon,truotlng • new
potentiometrtc map with the new thlhow wells tlrat, n lnttanlng lhl two
I newwefl pen. ~-We dllagree on 1ome detalll dlacuHIOn bUt egl'I• I
a, to 1~pe and ~oh. Would llke to aee 81ln'I ptt>ocnd well locatlonl.
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5. BFA g~a Into qune ti bit of dltcu .. lon and depth of
bel1eve ·their plan g~ beyond a rnaoneble extena n of the e,clatlnQ data
and ra1ie1 to • arMt extent on· 1uppoeltlon, uelt'lg enertc geologlo and
topogn11phJ0 data and lntetpretatlon to try to cover 111 onttngenclee.
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· Overall, their renonlng based on tt,eH pr1ndplea II tound, e,cwpt at I do not agree with
their ptoJeotlon of the ~ter table. ~FA'• proponl projects that th• tabla II mounded
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: M,. ~n M. Sorden
> September 20, 1998
bine•th the unit and elopes away radially. However, u•I~ the rtnctple that the water l .
table Is a 1ubdued reflection of the topographic aurfece <• pnnclple at they reference and
I I rely on), the projected wattr table ~ene•th ale before conetructlon the unit would flU off
to the north, eouth and west from the north, elnce the unit wa, bu on • ridge but not 1t
I the cre,t of the rtdg•. According ' to the topographic mapping, creet of the rldp II
located slightly •••t·of the untt. ~lther than a mound, there wo d be a 1llght gradient
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orfglnally under the tlte from eut to we1t. Since the water tabfe II arged from 1urfaol
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fnffltration end the un~ prevents lnfl~tlen In lta foOtpffrtt, the red recharge would retult
tn • allghtly lower water table und•r the unit, lncraa■lng th• gradle t from the eut to the
unit. 1h11 would 1llghtly 1ncrea,, U-,. gradltrrt from the ea,t part of e ridge to the unit and
• very 1Ught ~-In gradient f~ the unit to the wett. Tht:f'II It It a flattening of the
: water'table. not a mound. I
Some 1paotftc comrrlentt to tM B~A r.port
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Do not aee a need at thla tf:m• for PCB/dioxin an1lyale of • ii eamplea above the
wtater table.
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Agrn with ln♦tallatlon of ~II palra 1(A,B), 5(A), and 7(A). Mly uttlmltely need
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5(8) and t(B) but not yet demonstrated, ,o I lilt them at " •vbe'•"· Do need •
1hallow well on the weat tide 11 wen.
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H'7SS '0 966l-t7C:-C:
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' Ms. Ann M. Borden ·
September 20, 1998
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Rethtr than J,ut In deep wells at e1cl1tlng well• MW~3 and MW◄ and label them
I MM·3A and MW-'A, al d•ep welft ahould have tho 11me nomenclature 1yetem:
1hat II, the deep w.tte sh,ould be ''S" well, and U,t thal w "A" wella, •• BFA
auggett9 for ~ew wen pal1·
Do not bellava that new ~lie MW-e or MW~ art Juetlft et this ttme. If MW~
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were lnatalled, lt ,hould be' located further up the draw.
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Do not Uke baekground we)I, on 1noth1r ridge. Don't 1ee t e need for 3
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background weU. on tha1 ridge. Believe that further • y111 wm tho'N that . I ,
upgrldlent wtU 11 p011lble ;to 1he east of the unit on thff • ridge.
With the choice, would p~r 1everal eluo tette In this
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i During drffllns, of tftt borlnO• for new wtlla MW-1, MW-S, d MW-7, 1ol111hould
be 1ampted from 1urfaee. ~ot wait until get to bue elevatl of unit.
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BFA que1t10.,_ function of ~lltlni well MW• 1, llnee It '""' , I
Yet Bain looked at ,ame dale and 1te1n that au wtlla appe to be qu"9 fundoflal, . I
Need more Info, auch •• h~ don the well rech1rg• when b•lled for 1ampHng?
HOcl.:l H'1SS 0 966L-li'<3-G
Me. ~nn M. Borden :
September 20, 1&9G
MY RECOMMENDATIONS;
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I believe that we have tc learn how groundwater la ffowtn; In the I mediate vicinity of the
unit first, then we can extend the ~ystem based on that underatan Ing. hlatortcal record•
from the exlttlng wells, and umtetltandlng cf th• 1lte geology a topo;rephy.
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My reeommendatlon is to ln1tll T SMllow well at th• ■pproxlm• mid-point of the four
,Ides of the unit. Oeep WIiia ahou~ be lnltllled paired with the ,hallow well along the
eaatem elde or the unit and at exl.tlng welll MW-2, MW-3, end ... vu.-, Thia •v-tem of new
wells WiU eatabHlh thtn well rowa ~dialing ~m the p91r along the utem edge of 1he unit
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In the cfl1'9Ctton of tt,e thret main •waf• to the welt of tht Nate ridge.
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It wm alto provide a •et of four d8fJP w•II• covering th• ••me •r• . ! '
Water tev•t reading, wlll have to' be modelled to evelulte grou water flow dfrecllont
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around tht unit. Toll 1hould n~ b1 done with a 11mp1e co ting progr1m but be
modelled In fight of exl1tt,g topographic and geologlo concllttona. After thl1 modafflng It
· comp~te. en analysll can be. don~ to 1v,1u1te whether 1ddtt1onal 111a are needed (and
whtrt) and Which wtlls should be: 1ampled,
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' ' If there 11 any furth■r dl1ou11lon, I an, av11Jable 1t 872-zee<).
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SJncen,fy,
~ ~~ ~~no::l, c;;;E./
~ !mle iP•~r. P .E.,
Vice Prnldent
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{p GEi Consultan~, Inc.
$c,ptembef 16, 1996
MI.AanM, Borden
s•ME. lDc.
3190 Sprizas F~ ROid Rai,ip. North CarbllDI 27604
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Rt: Petr Rnt• or Work Pka Materlala
Warren Cftaae:y PCB i..d.tlll
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nnei.PomR...t
ffuflt1 .M
IWttall. NC Z76IS•901i
flP•e76•0de9
I In reply w your Jett,r io Steve Wht~idt dated September ◄, l 996, \i,e ollowia, lfll oonuuai.
on the mazeria11 you provided oli lbt Wan,a County PCB -~· I have eombmld Ill)' ~ on tho Stm't plan with~ 011 the Bamel, Ferllnd lDll Al~ltel plua_lO llallltall
~OAI. :
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Collll/fMU of~• L 111111 {Odpbtr /9, l99S ltnf~) .
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I qree thd' the ~ ~r src,undwater low in 1bt ma da laadftll Ollmot be
edtqua11ly evaluated wltll ~ exltdq well network. Addld momtorlaa MUI 1n
n11cleil tbr 1!lil purpoae. EvllUllioD uaa, ~ hn me.tltiq weUI
&Dd the uw wella lllly ~• 1he appumt OODIIUial n befflllG CU S•'•
In~ of'the dlrecti of wllow pomdwtiler ftow (to nonb IDd llOltbetlt)
ud ihe 1uriic1 topocr1J1h7 , the._ which dralnt pmnn, dillly from lbe landtlll.
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I b1ve DOI 'located •'Sheet 3, S~ri'1P • P.wi. 8112/IJ'" cited J.D hrm 2 of tho
lteaommtn4ed Ahemllo PltD. c~. J am Q01 le to comment cm tho
~om. !
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Statt Dr4'f JVarl:pld,,Jbr U~ rhl Ornnd Wat1r Monltorm, "" at rlr, ,Cl Lontllill
(.4prll 16, 1995) Oltt/ aam,,, F1rl(Md Md bloelall1, Int. '1 PCB . 11 Supp/1,,,,,,,aJ SIii
lmt1,,,,.lon Plt111 /s,mu,,,r 19H) ·
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The BPA plan refers"!:~"' S-.,1.ina P11A clla.d July 2. 1994." I bellev9 tblt plan wu aot lnduded m matlrial& provided. Con.,oquad1 I may saot ha~ tfm fi&ll
COllt•t of Pie woik by IFA. J 1111 om.tq ffll1IOll1I baed on ID)'
,m~I vf the ,t~ hill Iba ffllterillt provided.
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(Y) c... a a:: u. ~ <i r---11) (S) (.D (J) (J) ~ I q (\J I (\J . . < • ~ ! -( • • • < ' ' i' !s.il (l1lli" i.~i 61"i' frS-jlS-gl I . l ~~lI!! t!ill I! li,111111 l:ill!1!iJi!t; I r fl(il! f1rH 1: f1'ifif1fJJ l{l:iJ;JiJ,(J~~ ' .. .. u. , •0rr _ -as Ii s-• al!:-• ~r~I ~ -Jfss,a•1 la-l 1~i t I t~•~~1-. i~i!i!a!lllil ~ • ~,a~e J~lt ~ -~~&f~f-JI ''1·i:l"fifii; s.J~ r~~ ! r!r!~ -'~ ~, ~--1 f,e!: f r ltf 11w1 i gq•~1w,~1 1•·1r1s1111,~ ; tl ,, ,r( · I rllt ,,it 1fl fa.!-.talif I ( . • • . . . (
M1. A.1111 M. Borden
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Beca\UO it is more eomprebemlvi. tbe BPA pl8G will allO lit more QO to implemc,at. Olm1
the aoncn about the IOamWladon ol lnftllrldola water la the lan"1W cell IDd the rwuldq
c:oaOWD about the efrect oa ~WIier Q\llllty, Cb, coll of Cht on, ooqnbalve pl&
~ to be ~tlld tor~~~. n. 8FA plen pmvldes ,----·-probability of aly
~-of•toW&ehmthe~ Allo,lbmtomeconoena the&tata•splDclepeDIII
Oft me IAteq,rttatioa of the dinctfou of arounctwater flow bued oft level& ID ODly four
IDODitoria&welb; lt1beie ue~ oflballow pOllldwstcr D in diR•u atMl'daJD
north and no111san, work ~ ~ BPA'I plan 1, mare Ubly to oblaw tbtle
coq,cma.rs tbaa ~ work UDdlr,dle St&tt'tplu.
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I wallld be a1ad '°; ctilo1111 my~ wltll you or 'Mlb 1ba St1111.
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GIi CONSULT4NTS. IMC. !
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K9vlA lt Boyer, ~..E. I
~DtvbbaM~
KJ\B:ct
o: S11Ye Whlie.lde
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Joint Warren County/Sate PCB Landfill Working Group
draft August 27, 1996 Meeting Minutes
The regular meeting of the Joint Warren County/State PCB Landfill Working Group was called to
order at 4:45 P. M. Thursday, August 27, 1996 by Ms. Dollie Burwell. The meeting was held at
the Warren County Office and was co-chaired by Ms. Dollie B. Burwell and Mr. Ken Ferruccio.
A generic agenda was distributed.
READING AND APPROVAL OF MINUTES
Two corrections were made to the-April 25, 1996 meeting minutes. The approval of these minutes
were tabled pending those corrections.
Ms. Bobbie Riley moved the the minutes from the June 20, 1996 meeting be aproved with the
amendment that the April 25, 1996 meeting was tabled pending corrections. The motion was
seconded and carried.
UNFINISHED BUSINESS
Status of Sampling Plan
A report from the State was deliverd by Bill Meyer. Mr. Meyer reported that there are several
matters requiring agreement before the sampling plan can be completed. The three main issues
are: 1) increasing the number of monitoring wells, 2) the location of these new monitoring wells,
and 3) the parameters to analyze for. Mr. Meyer provided a document illustrating the locations of
proposed new ground-water monitoring wells, surface and sediment sampling locations, and one
area that will be hydropunched. (See figure 1.) This is the base of what the sampling plan
consists of and if the Working Group can agree on this, the project can move forward. Mr.
Meyer said that he has a draft sampling plan that can be put in place, then a lab can be selected
and sampling can begin.
Ms. Ferruccio said that the Technical Committee was expecting a meeting with the State and the
Science Advisors. At this meeting the State and the Science Advisors were to iron out all their
differences. After which, the Technical Committee was to receive a plan that they had all agreed
upon. She then asked if this was just the work of Mr. Meyer and the State. Mr. Meyer
responded that this is a consensus document that locates, new sampling points and existing
sampling points. A combination of the two plans will consist of what the sampling plan will
address. In addition we have consensus or. the location of new and existing points and what they
will be analyzed for. (See figures 2 and 3.) He explained that this is the object of the sampling
plan. How it is to be carried out is to be a~.dressed in another document. Tbat document will
discuss all issues of quality control, quality assurance, decontamination, and personnel protection.
Mr. Meyer said that when he spoke with some members of Working Group, he heard some
disagreement about doing additional sampling. With this in mind, he thought that the first step
would be to get the Working Group to approve these issues and the sequence of how things
would go, then a full sampling plan would be developed. Mr. Ferruccio asked Mr. Meyer if what
draft August 27, 1996 Meeting Minutes
Page 2
he was saying was that he wants input from the full group in the formulation of the full sampling
plan. Mr. Meyer said that what we need from the Working Group is approval of the sampling
locations, the number of new wells, and the parameters to test for. Once we have that, we will
know what the market is and how to draft documents needed to get a lab to assist in
implementing the sampling plan.
Ms. Burwell then said that the Technical Committee was set up for a purpose and that purpose
was to be a liaison between the Science Advisors and the State. The Technical Committee is to
review, inform, and bring recommendations to the full Working Group. They are to share with
the full Working Group the discussions that they had with the Science Advisors as justification for
their recommendations. On the matter of a disagreement with additional sampling, there was no
disagreement because the Technical Committee knew nothing about additional sampling. They
had not received information that the State and the Science Advisors had agreed on a plan. If the
process had been followed that Technical Committee would have had time to discuss this plan
with the Science Advisors and bring a recommendation to the Working Group. Then the
Working Group could vote on the plan. Ms. Holcomb asked how much of the Science Advisors
input went into this plan. Mr. Meyer advised that meetings were held and a consensus was met.
Ms. Ferruccio said that the Technical Committee had a conference call with the Science Advisors.
What she understood from that call was that they had given their portions of the plan to Mr.
Meyer and was waiting on him. The Technical Committee did not realize that a consensus had
been met and all that they wanted was to see what that consensus was. Mr. Hirschhorn stated
that the Science Advisors had a meeting with the State on July 3, 1996. At that meeting a
consensus was met on many basic key issues. Those issues included a general frame of work,
security system to be used rather than split samples, procedures and protocols that are important,
and division of work. All of this was done to create a document that would be brought to the
Working Group for approval. Mr. Barnes advised that this portion of the work was to be to Mr.
Meyer by the 17 July and was faxed to Mr. Meyer on the 18 July. A few weeks later Mr. Barnes
got a response from Mr. Meyer advising that more work was needed on his portion. The results
of this were given to Mr. Meyer this morning. Mr. Barnes said that he feels that was his final
input and that the final document would come from Mr. Meyer. From the conference call with
the Technical Committee, Mr. Barnes said, there were concerns that the Technical Committee
was being left out of the loop of communication. Therefore, Mr. Barnes has put together what he
has done and will give to the Technical Committee along with the State. Ms. Ferruccio voiced
concern that we are not sticking to the schedule of the Master Plan. Because of this she feels that
things are not moving forward. The Technical Committee thought that things would move along
concurrently. Ms. Burwell said that we need to come back to this because nothing is being
resolved. She went on the say that this was the focus of the conference calls. Reports were
promised and not delivered and no explanation was given about why the reports were not
available. Ms. Riley said that the whole purpose of this meeting was to vote on the sampling plan.
She said it is true that the Technical Committee was to have this report ahead of time. Since the
plan does not look complicated and since the Science Advisors are here, the Working Group
should hear their input and advise. Ms. Riley asked if this is what we are to look at to say yes or
no to and then the full document is done. As explained by Mr. Barnes, this is the base for the
plan. Then Mr. Meyer added that the other part is process. Ms. Holcomb asked Mr. Meyer if
draft August 27, 1996 Meeting Minutes
Page 3
the locations of the new wells were on the document that he had provided. He responded yes and
explained that monitoring wells 16, 17, and 18 are off-site background wells. He also said that
we have to negotiate with the property owners to allow us to put wells on private property. Next,
Ms. Burwell asked to hear from the Science Advisors. Mr. Hirschhorn recommended that the
Working Group approve the plan so that the Working Group can move forward. Ms. Riley asked
the Science Advisors if the plan looked like what they had agreed to and Mr. Barnes said yes.
Also discussed was the fact that the Working Group is continually being asked to approve things
that have just been presented to them. Then they are made to feel guilty if they do not. Mr.
Barnes said that he understands the concerns. He did get that impression from the last conference
call, so he has put together three (3) notebooks on the project. These notebooks include his part
of the sampling plan and are for information only. He advised that the Technical Committee can
use the notebooks to gain information the Working Group needs to help them make decisions, so
the next time they can feel that they are making an informed decision. Mr. Barnes noted that the
only thing that had not been mentioned was the Master Plan. He advised that he and Mr.
Hirschhorn spoke and decided to work on the Master Plan. Mr. Barnes said this is a draft, but it
would give an idea of how they recommend the project proceed. These notebooks will include
rationale why the monitoring wells were placed in specific locations. Mr. Hirschhorn added that
the Master Plan was discussed, presented, and given approval. He said that then the Science
Advisors were told to fill in the details and that is what happened at the meeting with Mr. Meyer
and his staff. So what the Working Group is getting is consistent with the strategy presented.
Mr. Barnes said the schedule has changed, but goals, objectives, and intent of the project had not
changed. ,
Ms. Riley asked if PCBs, dioxins, and furans are being analyzed at the same levels that the State
labs uses. Responding, Mr. Hirschhorn said that we are using the most sensitive test, EPA
method 8290. Another issue was that the EPA has developed new guidelines for drilling wells to
test for low level organics. Mr. Meyer, advised that the last time each sample cost $1150.00 and
that total was $30, 000.00. With the addition of twelve (12) more samples, the cost would be
approximately $150,000.00. Mr. Meyer said the issue here is that the test are expensive and costs .
are an important consideration. So the State may have to come to the Working Group and say
that we need to do ten (10) wells instead of twelve (12). When the Science Advisors presented
the alternate technology, part of what they explained was that it did not make economic sense to
spend money on onsite pilot technology testing. Because monies would need to be spent in ways
that would get the results that the Working Group wanted. Ms. Burwell said that when the State
and the Science Advisors came up with twelve (12) wells, cost should have been considered. She
also said that the Working Group did have some concerns with semiannual testing and the voted
to include dioxin testing. Where the money came from for this dioxin testing, she was not sure.
If all testing done to keep the landfill in compliance comes from Mr. Meyer's operating budget,
then if this was a problem, he should have said so. Mr. Meyer advised that most of the money for
the past twelve (12) years has come out of his operating budget. Money for dioxin testing came
from his department's budget. Ms. Burwell asked Mr. Meyer if there was money in his budget for
compliance testing. When he developed these new wells, did he see a problem with paying for
them. The response was that money has to come out of the million dollars appropriations. Ms.
Burwell asked why the PCB fund would be paying for semiannual testing and Mr. Meyer
draft August 27, 1996 Meeting Minutes
Page 4
responded that this is not semiannual testing. He said that this is a site investigation to determine
three (3) things: 1) the medium contaminated inside and outside the landfill, 2) the form of the
medium, whether it is liquid or sold, and 3) the volume of that medium. Again, Mr. Meyer
advised that the only part that the State does not pay for is the cost of dioxin testing. The
members of the Working Group then advised Mr. Meyer that when they told that dioxins were
present, he also told them that there was money in his department for dioxin testing. Mr. Meyer
said there was money in his budget for a one time sampling event. Ms. Holcomb then read from a
letter dated August 24, 1995. (See figure 4) Mr. Meyer advised that was a,statement of what
things cost, but no commitment for State funds to be used. After more discussion on whether
dioxin testing was to be added to compliance testing and therefore paid for by the State, Mr.
Cooper moved that the scope of the sampling plan be approved. The motion was seconded and
carried. Abstaining from voting was Mr. Ferruccio. Opposing the motion was Ms. Burwell.
NEW BUSINESS
Extraction of Material
Mr. Hirschhorn asked the status of the extraction of materials for bench-scale testing. Mr. Meyer
said that last February, eleven (11) companies showed up with specific designs based on taking
material out of the landfill. That RFP is still valid and he hopes to use the same companies. We
need approximately 2,000 pounds of sample for the bench-scale test. We can have seven six-inch
wells in landfill at twenty-four feet deep or two twelve-inch wells at twenty-four feet deep. Mr.
Hirschhorn asked if an EPA permit would be needed for this removal. Mr. Meyer said as long as
PCBs do not leave the site and that all storage requirements for toxins are met, that he has been
assured verbally that no EPA permit would be needed. However, he is not .sure if there is a time
frame associated with this storage. "The breaching of the integrity of the landfill is a major factor
and I doubt that the EPA would give approval so quickly for this," said Mr. Hirschhorn. "The
RFP had a safety measure built into it," said Mr. Meyer. Companies would have to submit a
design so that the State and the Science Advisors would be assured of no violation to protection
of the cap. Continuing, Mr. Meyer said what Mr. Hirschhorn is talking about is a regulatory issue
that may prohibit this. Ms. Burwell said that when the Working Group had a meeting with the
EPA she thought that Mr. Meyer got that approval in writing shortly after that meeting. After
more discussion on the matter of the permit, it was clear that the Working Gro11p thought Mr.
Meyer had received written approval from the EPA. Mr. Cooper said that the concerns being
voiced are legitimate and the problem is that we do not have a director, who would see that things
are done. We need a paid individual who will work with the Science Advisors and is responsible
to this committee. Mr. Hirschhorn advised that with other community group, he has had the
authority to speak for them and negotiate with government officials; however strategic issues
came for the community group. Ifwe had a director, the director would tell the Science Advisors
and the State what needs to be done. He would be speaking for the Working Group and would
be held accountable when things are not done. Ms. Burwell said that she feds if Mr. Meyer felt
that this project was more than he could handle, with his other responsibilities, than he should
have come to the Working Group or the Technical Committee and said so. Mr. Meyer stated, as
of August 20, 1996, I have a part-time person working twenty hours a week on this project. I
recognized that I do not have the time and that is why this person was hired. Questions were
draft August 27, 1996 Meeting Minutes
Page 5
asked and it was discovered that this person will work his full twenty hours on this project, that
the Science Advisors can go directly to this person and not to Mr. Meyer, that this person will be
attending the meetings along with Mr. Meyer, and that this person is now the Project Director and
will have authority to make decisions. Ms. Burwell called for a motion for a Project Director
whose purpose would be working with the Science Advisors and making decisions. Mr. Meyer
wanted it to be clear that he will not be spending less time on this project. He feels that this
project will take his time and the Project Director's time. He also wanted it clear that this person
will be the lead person and will do any leg work that needs to be done. And he, Mr. Meyer, will
be available for any assistance he can provide the Project Director. Mr. Cooper asked if the
Project Officer would be responsible to the Working Group or to the State knd therefore where
will his loyalties lie. The Project Director will be working for the State, said Mr. Meyer. Mr.
Hirschhorn said that we still have a problem, will Science Advisors have authority to tell this
Project Director what to do. After additional discussion it was apparent that the Science
Advisors are not decision makers. The Working Group will make decisions based on the advice
and recommendations of the Science Advisors. Mr. Hirschhorn voiced concern that the Working
Group wants to make every decision. He said that the people who hire him do so because they do
not have the qualifications to make decisions that need to be made, where technology is
concerned. Ms. Burwell said, when the Science Advisors were hired they knew the process by
which this work was to be done. The Science Advisors understood that the Working Group had
the power and authority to make decisions and recommendations to the State. That their role was
to help the Working Group make decisions, not to make decisions for them. Ms. Holcomb asked
Mr. Meyer if the Project Director will be paid from his department. He replied no, from the PCB
fund . There was more discussion on the source of funding for the Project Director, and to whom
he will be responsible. The Working Group feels that if they pay for the services of a Project
Director that they should have say so about who is hired. Mr. Lancaster explained that the State
has to play a role in terms of the State's property interest and liability for thJ project. So we, the
State, must have someone directly involved and right now that is Mr. Meyer. He is trying to
transfer that to someone else and requesting that you allow the money to come from the million
dollars. The State does not have the funds for a Project Director, therefore if the funds do not
come from the million dollars then this falls back in Mr. Meyer's lap. Next, the motion was made
to table the Project Director until the next meeting. Meanwhile we will get an update on what has
been spent and a projected budget. This budget will include the amount for: the Project Director,
analysis, wells, vendors, etc. The motion was seconded and carried. ·
Next, Ms. Elmore made a motion that we get in writing from the department the roles,
responsibilities, and decision making authorities of the Working Group, Mr. Meyer's department,
and the Science Advisors. This should be made available at the next meeting. The motion was
seconded and carried.
Mr. Hirschhorn said that there is another area that needs a motion. That is who is to approach the
EPA about what permits or authorities are going to be necessary to take material from the landfill.
It was motioned that Mr. Meyer's office gets in writing the EPA's requirements for excavating
material from the landfill. The motion was seconded and carried.
Vendor Technology
draft August 27, 1996 Meeting Minutes
Page 6
Ms. Ferruccio bought up the subject of vendor technology. She asked Mr. Hirschhorn what
information is needed from the sampling to continue his work with vendors. Mr. Hirschhorn
advised that there are two viable technologies with several vendors. He also advised that there
are tougher issues that need to be addressed. One issue is how to structure the RFP and that
cannot go on until Mr. Meyer works out two aspects. First, he has to get a contractor lined up to
do the extraction and second, he has to deal with regulatory issues. These are barriers for going
forward. Ms. Freeland suggested a meeting with the Science Advisors to work that out. Mr.
Meyer advised that he will contact the EPA and send correspondence to the Technical
Committee. At which time the Technical Committee can decide a date to meet based on progress
with the EPA. Mr. Hirschhorn advised that he would be sending a memo addressing some issues
and would have it available to the Technical Committee next week.
ADJOURNMENT
; The meeting was adjourned by co-chair Ms. Burwell at 7:30 P. M. The date for the next meeting
is Thursday, September 26, 1996 at 4:30 P. M .. A Technical Committee meeting was scheduled
for Thursday, September 12, 1996.
Doris R. Fleetwood
Warren County/State PCB
Working Group Secretary
),. 0 0 :r 0 n> i to ~-0 "' , ::,-s· ) to 2 0 OQ ; "' a ) s 0 :r 2. '2. 0 n> "' s· OQ ! iii \ I I I I I ', \ ,
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\ ,
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....
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', I ', ' .... ............ ....
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I I I I I I I I I ', ', ......... __ _
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(
FIGURE 2
DRAFT SAMPLING LOCATION/ANALYSIS PCB LANDFILL
ANALYSIS
SAMPLE ID
LOCATION
GROUND WATER
I MW-IA-NEW EAST
2 MW-IB-NEW EAST
3 MW 2-EXISTING NW
4 MW 3-EXISTING WEST
5 MW-3A NEW WEST
6 N2-4 EXISTING SW
7 MW-4a NEW SW
8MW-5NEWN
9MW-5aNEWN
10 MW-6 NEW S.E DRAW
11 MW-7 NEW SOUTH
12 MW-7 A NEW SOUTH
13 MW-8 NEWN. E. DRAW
14 MW-9NEWN. DRAW
15 MW-I0NEWW. DRAW
16 BACKGROUND WELL I
17 BACKGROUND WELL 2
18 BACKGROUND WELL 3
PCB
✓
✓
✓
✓
✓
✓
✓
✓
✓
✓
✓
✓
✓
✓
✓
✓
✓
✓
DIOXIN/
FURAN
✓
✓
✓
✓
✓
✓
✓
·✓
✓
✓
✓
✓
✓
✓
✓
✓
✓
✓
BN/AE
✓
✓
✓
✓
✓
✓
✓
✓
✓
✓
✓
✓
✓
✓
✓
✓
✓
✓
voe METALS OTHER
✓ ✓ ✓
✓ ✓ ✓
✓ ✓ ✓
✓ ✓ ✓
✓ ✓ ✓
·✓ ✓ ✓
✓ ✓ ✓
✓ ✓ ✓
✓ ✓ ✓
✓ ✓ ✓
✓ ✓ ✓
✓ ✓ ✓
✓ ✓ ✓
✓ ✓ ✓
✓ ✓ ✓
✓ ✓ ✓
✓ ✓ ✓
✓ ✓ ✓
Background wells located 1-2 miles off-site in NW, SW and SE quadrants. Attached is list of constituents and
detection levels for each analytical test. Wells m2-6,8,9 and 10 may require a nest if hydrogeological
conditioning warrants.
Total Samples/ Analysis
40 total; PCB 40; Dioxin/Furans 40; BN/AE 23; VOC 23; METALS 23 x7= 161 (As, Ba, Cd, Cr, Pb, Hg, Se)
DRAFT SAMPLING AND ANALYSIS PCB LANDFILL
SAMPLE ID
LOCATION
LEACHEATE
19LEACHEATE INLET
PCB
20 LEACHEATE OUTLET
SAMPLE ID
LOCATION
SURFACE WATER
21 SW-1 SOUTH UT NEW
22 SW-2 SOUTH WEST UT NEW
23 UTUS EXISTING
24 RCUS EXISTING (Below Bridge)
25 RCDS EXISTING
26 RCUS NEW (Above Bridge)
SAMPLE ID
LOCATION
SEDIMENT
27 USSS-ABOVE BRIDGE ON RD
28 BB BELOW BRIDGE ON RC
29 SS-1 SE DRAW ON UT
30 SSND N DRAW ON RC
SAMPLE ID
LOCATION
POND SOIL
31 PS-1 OVERFLOW PIPE BASE
32 PS-2 CENTER OF POND
DIOXIN/ BN/AE
✓
✓
FURAN
✓
✓
PCB
✓
✓
✓
✓
✓
✓
PCB
✓
✓
✓
✓
PCB
✓
✓
✓
✓
DIOXIN/
FURAN
✓
✓
✓
✓
✓
✓
DIOXIN/
FURAN
✓
✓
✓
✓
DIOXIN/
FURAN
✓
✓
33 PS-3 DISCHARGE PIPE OUTLET ✓ ✓
SAMPLE ID
LOCATION
BLANKS
34 TRIP 1
35 TRIP 2
36 SOIL 1
37 WATER 1
38 WATER-2
39WATER-3
40 HYDRO PA
41 LANDFILL SOILS
PCB
✓
✓
✓
✓
✓
✓
✓
✓
DIOXIN/
FURAN
✓
✓
✓
✓
✓
✓
✓
✓
voe METALS
✓
✓
BN/AE voe
✓ ✓
✓ ✓
✓ ✓
FIGUREJ
OTHER
✓ ✓
✓ ✓
METALS OTHER
✓
✓
✓ ✓
Other for landfill soils include particle size distribution engineering classification, liquid limit, plasticity index, moisture
content, organic matter, nutrients
State of North Carolina
Department of Environment,
Health and Natural Resources
Division of Solid Waste Management
James B. Hunt, Jr., Governor
Jonathan B. Howes, Secretary
William L. Meyer, Director
FIGURE4
August 24, 1995
MEMORANDUM:
TO: Members of Working Group
FROM: Bill Meyer
NA
DEHNR
SUBJECT: Expanded Groundwater Monitoring On The Landfill
Enclosed is the previously submitted proposal for additional groundwater monitoring efforts on
the landfill. I will request that George Bain (private hydrologist that I think is both an expert and
unbiased in his perspective) review and comment on the proposal. I hope George will perform
this review free of charge. I would like to have the very best input to locate and design the
monitoring system.
It may be appropriate for the Work Group to consider giving directions for implementing the
expansion of the groundwater monitoring system. EPA Region IV has offered assistance with
sampling both new monitoring wells and the existing monitoring systems.
P.O. Box 27687, Raleigh. North Carolina 27611-7687 Telephone [phone] FAX 919·715--3605
An Equal Opportunity Affirmative Action Employer 50% recycled/ 10% post-consumer paper
FIGURE4
CON'T
Workplan for Upgrading the cround Water Monitoring System at the
PCB Landfill
summary
The Solid waste Management Division <SWMD) has evaluated the current
ground water monitoring system, consisting of four wells, at the PCB
Landfill. The SWMD recommends upgrading the current system by
Installing six addltlonal wells. TWo wells would° be coupled with existing
wells MW-2 and MW-3, to form well nests. The other four wells would be
Installed north and northeast of the landfill In two well nests. Each well
nest would Include two wells Installed adjacent to one another and
screened at different Intervals. Assuming no unexpected circumstances
are encountered, the upgraded monitoring system should provide the
PCB Landfill with a better detection monitoring system.
Jntroductton
The PCB landfill ls approximately 3.7 acres In size. The landfill was
constructed such that approximately 50% of the cell was above the natural
grade and 50% below. Based on blue line drawings of the landfill, It Is
estimated that the landfill, Including the liner system, was approximately
38 feet thick and ranged from elevation 354 feet to approximately 316
feet above mean sea level.
The current ground water monitoring system at the PCB landfill was
Installed In 1982 and consists of four monitoring wells screened In the
surflclal aquifer .. These wells range In depth from 39 to 51 feet and are
completed between 10 and 17 feet below the water table.
Hydroaeotoav
The parent rock beneath the PCB landfill has been mapped as a mica schist
by the North Carolina Geologic survey. The estimated depth to
competent bedrock Is between 70 and 90 feet. saprollte and residual soils,
Including silty sand, sandy silt, and clay, overlie the bedrock.
The ground water flow direction at the site varies seasonally between
north and northeast. During the winter and spring, the flow Is generally
to the northeast and during the summer and fall the flow Is generally to
the north. Monthly water level measurements, collected over a two year
period from the four on-site monitoring wells, were used to determine
1 of 4
FIGURE4
CON'T
the trends In the ground water flow direction.
The water table extends Into the silty sand unit or the upper portion of
the saprollte. The average water table elevation varies between the
monitoring wells from a high of 319 feet In the upgradlent well to a low of
295 feet above mean sea level In the downgradlent well .
.
Piao for uograding the Ground water Monitoring system
The plan for upgrading the ground water monitoring system at the PCB
landfill has several goals Including: better definition of the lithology
underlying the site; determining the vertical component of ground water
flow; defining any variations In the ground water flow direction In the
residual soils and the saprollte; and determining the ground water flow
rate.
lnltlally, the SWMD recommends the Installation of six monitoring wells.
one well would be Installed adjacent to MW-2 and one well adjacent to
MW-3. These wells wlll probably be completed In the saprollte zone,
Immediately above the bedrock surface <auger refusal>. The saprollte Is
expected to range from 60-90 feet below land surface.
The other four wells would be Installed as two well nests, north-northeast
of the landfill and as close as technlcally feasible to the landfill. Each well
nest would Include two wells Installed adjacent to one another and
screened at different Intervals. Within each well nest one well would be
screened below the seasonally low water table and one well would be
screened In the saprollte zone. The specific screened Interval for the wells
would be selected after reviewing the lithology encountered In the boring
and the boring logs from the other wells. Figure 1 attached Illustrates the
recommended locations for the proposed wells.
After all of the wells are Installed, the SWMD recommends that aquifer
testing be performed on selected wells. Data from this testing would
provide an Indication of the hydraulic conductivity oo of the subsurface
material. The K values would enable the SWMD to develop an estimate of
the ground water flow rate.
At the conclusion of this work and assuming no unusual circumstances are
encountered, these six wells, In conjunction with the existing wells, should
provide a better ground water monitoring system for the PCB landfill.
2 of 4
Eleld work ou1ctennes
FIGURE4
CON'T
All fleld work shall be conducted In conformance with accepted
engineering and geologlc practices as well as the Groundwater section's
Guidelines for the Investigation and Remediation of Solls and Groundwater
and the Hazardous waste section's Sample Collectloh Guidance oocu,nent.
Well lnstallatlon shall be In conformance with the North carollna Well
construction standards. A site safety plan shall be developed and
followed by all fleld personnel. All appropriate decontamination
procedures documented In the references above shall be followed.
During the Installation of each boring/well, a Quallfled geologist shall be
present and a boring log completed for each well. Spilt spoon samples
shall be collected at a minimum of every five feet and where there has
been a significant change In the penetratlon/drllllng resistance. Soll
cuttings shall be containerized until the analyses of ground water samples
have been received from the laboratory. At such time, the appropriate
disposal option shall be selected.
Each well shall be constructed: a> In accordance with the attached
diagram; b> In conformance with the State's well construction standards;
and c> to be capable of yielding a ground water sample representative of
the ground water quality at that location. The well casing and screen shall
be constructed of 2 Inch diameter PVC. The manufactured well screen
shall be sized appropriately, according to the soll type. Each well shall be
completed with a s or 10 foot well screen. The annular space from the
bottom of the borehole to a distance of 2 feet above the top of the well
screen shall be filled with an appropriately sized sand pack. A two foot
bentonlte seal shall be placed on top of the sand pack. Above the
bentonlte seal the annular space wlll be fllled with a bentonlte-cement
grout. Each well shall be completed with a protective steel outer casing
and a locking cap. A sloping pad shall be constructed around the base of
the well In order to direct water away from the well.
Upon completion of the well, a water level measuring point shall be
established and the elevatlon determined to the nearest 0.01 foot.
Each monitoring well shall be developed after the seal and grout have
stabilized and no sooner than 24 hours after completion of the well. The
well shall be developed until all suspended materials are removed or a
reasonable volume of water has been removed. All well development and
purge water shall be containerized untll the analyses of ground water
samples has been received from the laboratory. Atsuch time, the
3 of 4
FIGURE4
CON'T
appropriate disposal option shall be selected.
After all wells are completed, hydraulic conductivity value<s) will be
developed for the aquifer. A minimum of six slug tests or one pumping
test shall be performed In order to develop the hydraulic conductivity
value<s). The specific wells to be used In the aquifer testing shall be
selected after an evaluation of the soll sample descriptions has been
completed.
Renart
At the conclusion of the field work a brief report will be prepared
describing the upgraded ground water monitoring system. The report
will Include: a) a narrative of the work completed; b> a generalized cross-
section and c) an updated potentlonietrlc map.
4 of 4
Steel Outer Casing
1 plastic inner casing)
Land
Neat Cement Grout
Well Casing
(2" or larger diam.)
Palletized Bentonlte ----1~
Gleen Washed
Sand or Gravel
Lockin,J Cap
FIGUR
C T
-r. ... -
N Surface
• ///--~ ... -~
IO • . . . ....
_j_
"' C1) ·-... cu >
• ... -('IJ
'
FIGURE 13.
NOTE:
1. Borehole to be
larger than outside diameter ol
casing .
2. Casing and screen to be
centered In borehole.
3 . Top of well screen should not
be above mean high seasoned
water level.
4. Casing and screen material to
be compatible with type of
contaminant being monitored .
5. Well head to be labeled with
highly visible warning saying:
•well is for monitoring and not
considered safe for drinking. ,,
6. Well to be afforded reasonable
protection against damage
after construction.
ows 10/!-4
Recommended Construction Details For A Contaminant Monitor Well
In An Unconfined, Unconsolidated Aquifer.
l\tIEMORANDUM
TO: To PCB Working Group
'
FROM: Patrick Barnes, P. G., Science Advisor
DATE: October 23, 1996
SUBJECT: Amendment to the monitoring well installation RFP
I recommend that the Drilling RFP dated September 18, 1996 oe amended as follows to include
the following language:
1. The diameter of the proposed wells will be 4 inches I. D.
2. The proposed wells will be constructed of type 316L stainless steel.
3. The depths used for bidding purposes shall be 45' for the shallow wells and 90' for
the deep wells.
4. If necessary the contractor will attempt to drill past potential shallow obstructions
a minimum of three times.
5. The supplemental sampling plan be included as a working plan for the RFP .
Ti JXI(. Cl IEM/(1\/.
Sf"fOAI 15/~
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143 Dennis Street
Rockwood, Onta{jo
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ECO LOGIC Technology Update -Oct, 1995 Pagel
The ECO LOGIC Process
A GAS-PHASE CHEMICAL l'lEDUCnON FROCESS
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INTRODUCTION
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The goal was to de\·elop a commercially-viable chemical
process that could deal with aqueous wastes and also
process concentrated organic wastes (e.g. solvenLc;, oils,
industrial wasies, pesticides and chemical warfare
agents). Other companies and agencies were focusing
their efforu p1imaril)' on incineration, and were
investigating a variety of pre-destruction cleaning or
dewatcring processe.s to deal with the problem of aqueous
wastes. The ECO LOGIC Process was de~eloped ID ·
avoid the e,cpense, technical drawbacks, and regulatory
is<;ues of incineration, while still providing high
destruction efficiencies and waste volume capabilities.
Following bench-scale testing, a !ah-scale process unit
\>.,.d.<i constrneted in 1988 and tested exte~ively. Based on
these tei:t results, a mobile demonstration-i::cale unit was
constructed and commissioned in 1991. The
demonstration-scale unit was taken to HamHton Harbour,
Om:.ario, where ECO LOGIC processed coal-tar-
contarninated harbour sediment and poly-chlorinued
biphenyls (PCBs). In 1992, the same unit was taken
through a second round of tests as pan of the United
States Environment.al Protection Agency's (USEPA)
Superfund Jnnoviition Technolo~ Evalu.!tion (SITE)
program in Bay City, Michigan. In this test program, the
demonstration-scale unit processed l'CBs in aqueous.
organic and soil matrices. Based on the operating
experience and test results jarnered during the
demonstration pha.'ies of development, c..:ommercial-scale
proces,; units have been cunstn1cted and commissioned.
The attributes of the ECO LOGIC Process C'.111 be
swnmarized as follows:
• destruction of organic conuuninants at any
concentration and in any combination,
• proven destruction and 1e1mval eflicieucies of
at least 99. 9999 % ,
• commercial-scale mobile system for on-site
treatment,
• closed-loop destruction proce:..c; with no
uncontrolled emissions.
• not an incinerator; no possibility of dioxin or
fimm formation,
• permanentl)' destroys organic conr.aminants
eliminating the need for off-site dispo~aJ of
hazardous organic residuals,
• continuous process monitoring ar.d t011uol;
permanent record of destructbn ef1icie11c.y,
• successfully demorn,tr.ned for the l!nited
States Environmental Protection Agency;
evaluation reports available,
• successfully permitted in several juris•dictioru;
in close proximity to residential propenies,
and
• reasonable processing cost.
ECO LOGIC PROPRIETARY INFORMATION
_E_C_O_L __ O_G_I_C __________ r,_ec_h_no_l...:ogy::;._U....:.JXl_at_e_-_o_cr_. _1_99_5 _______ P_...agt 1
PROCESS CHEMISTRY
The E<;O LOGIC Process utilius vapour phase chemical
reduction to reform organic conwnin.tntS into re-usable
or recyclable materials. These rtactions take place in a
hydrogen-rich reducing atmosphere at elevated
temperawres under nominal pressure. The Process
essentially breaks down any organic compound into its
constituent elements and reforms them into methane, or
natural gas. This gas product is &iphoned from the
Process, tanker~ and tested. Following the analytical
verification phase the product gas may be re-used on-&ite
10 heat various ancillary Process component$. When
chlor~ organic compow¥is such as PCB& are treated,
hydrogen chloride (HCl) i.~ also produced and is removed
as recyclable acid by an initial leg in the ga.c. scrubbing
system.
The ECO LOGIC Process also employs "steam
reforming" or •water shift~ reactions to recover the
hydrogen from the methane gas product. Methane and_
wa~ react 10 produce carbon dioxide and hydrogen, the ·
laaer of which may be recycled back into the reactor to
further faciHtatt U1e reduction of organic compounds.
The benefit of using an actively reducing hydrogen
atmo.~phcre for the d~struction of chlorinated organic
compourvis is that formation of dioxw or furans will be
eliminated. Testing has demonstrated that dioxins and
furam are actually destroyed by the ECO LOGIC
Process.
DEMONSTRATION TESTING
Following bench and Jab-scille testing a demonstration-
scaJe unit w33 constructed in 199 l. This unit was
dcmc~ted in Hamilton Harbour, Ontario, on ~iment
cont.lmill4ted with up lO 300,000 mg/kg (dry weight
basis) polyaromatic hydrocarbons (PAHs). Three test
runs were performed on the sediment with the third run
being spikoo with SOO mg/1:g PCBs. Product gas
g~nerated by the ECO LOGIC Process was routed to a
boiler to enable the calculation of deslTUction and
removal efficiencies (DREi;). A5 shown in T11ble l,
DREs of 99.9999% wer~ calculated ba.~ed on the total
organic input and the PAHs analysed in the holler st.ack
emissions[l J. The concentrations of PCBs in the air
emissions. liquid eOluent and processed solids wete all
below the dei:ect.ion limits resulting in a PCB DRE of at
least 99. 9999 ~.
The same demonsuation-scale unit was mo\-ed to Bay
City, Michigan, in 1992 for performance eYaluation
under the USE.PA'& SITE program. The wastes
processed included oily PCB-contaminated water, high
strength PCB oil, and PCB-contamina~ soil. These
media had initial PCB concentrations of 3,800 mg/kg in
water, 25 .4 9' in oil and 600 mg/kg in soil. TI1e results
of the test program, as confirmed by the USF..PA(2], are
shown in Table 2. Target DREs of 99.9999% were
achieved for all six oil and water runs. ECO LOGIC
also demonstrated the ability to compress and store the
product ga! and operate c.ontinuously for an extended
period of time,
A~ part of the SITE program, ECO LOGIC cm~trucl.f>..d
and commis.c.ioned a prototype thermal desorption unit
(TDU) for desorbing organic contaminants from soil.
This ~ of 1he demormration was intended as a H proof
of concept· and the desorption efficiencies are
summariud in Table 2. It shouJd be noted that the
performance of the TDU is independtnt of the
destruction pr~ and that DREs for the desorbed
contaminants were high for both TDU ruM.
THE SE-2S COMMERCIAL-SCALE UNIT
Following the SITE demonstration jn 1992 efforu; were
focussed on optimizing the system for commerciaJ
operations. Th~ involved scaling-up U-1e system and
modifying preprocessing equipment to handle soil arid
solid matrices. 'lbese effortc; have culminaLt:d in the SE·
25 commercial-scale unjt.
The SE-25 system ~ compo~d of a reactor and ~rub~r
unit, a thermal reduction mill (TR~f) for soils
processing, a sequencing batch Vilpourizer (SBV) for
treating bullc solids. as well a.~ proce~!-control, htboratory
and decontamination facilitie.ci, The system is fully
mobile with the indh•idual componenL~ mounted on
st.and1rd highway trailers.
The ECO LOGIC Process focusses around a now-
through reactor operaLt.-d in a clo~d-loop mode with no
uocomrolled auno~pheric emissions. ll1e various
ECO LOGIC PROPRIETARY INFORMATION
' ECO LOGIC Technology Update -Oct, 1995 rage 3
Table 1 HAMILTON HARBOUR FERFORl\l<\NCE TEST RESULTS
~ -'""·-·" 1!11 , ~ ~ ldlt"i:: ,:1 "'" • 11'1:!ll':e::!I .. • ... .,, .... , .. , . .., ... I .. 0 1 '" IU ......... ,, ... ,. 11•1t1~-
Cone.in Decant Grit Sludge Srnck.
Target Waste W~ter Cone. Cone . Cone. Gas Cnnc. DRE
R\.tr1 Analytes (mg/kg) (µg/kg) (mg/kg) (m~/kg) (µg/111~) (%) ___
Pl PAils 21,000 483 1.67 32.S 0.27 99 .999~
Pl PAJh 30,000 680 7.76 56.) 0.23 99.9999
f3 PAHs 30,000 423 0.37 4J 0.14 !-!9 .~'99?
P3 rcBs 500 ND ND ND ND 99.9999
__ t • St..,ck Emissiom) / (Total Jn@l) ~-==--·--·--··-·----·-·----·----
'I able 2 USErA SITE rROGRAM RESULTS
:a:,urn n ... ~:x.u;::w:.::,,_~..:::=:::::=:=t.;_~.--
Concemr ation Tnrge-t
Run Waste Type Contarninant (rng:/kg) DRE!J)E .'\t:ht!.:Vt d ... _____
Water/OH rcBs 4,36S 99 9999 Yt:s
Trn.cer Perchlo1 oelhene · . 4,670 99.99 Yes
2 Water/Oil f'CBs 2,217 99. 9999 Yes
Tracer Perchloroethene 2,360 99.99 Yes
3 Water/Oil PCBs 4,689 99 .9999 Ye~
Ttacer PerchloroeUlene 6,100 99.99 Ye~
4 Oil PCBs 254 ,000 99.9999 Yes
Tracer Petchlornelhen!! 33,000 99.99 Yes
5 Oil PCBs 254,000 99 .9999 Yr:s
Tracer Perchloroethene 26,000 99.99 Yes
6 Oil PCBs 254 ,000 99 .99'.)9 Ye~
Trac:er Perchloroethene 34,000 91.99 Ye~
ConcenLrat.ion Dt.'SIH pti nn Efliciem:y
Run \Vaste Type Comarnimint (mg/kg) t%)
Soil PCJh 538 9,'\
Tracer IICB )2,<100 .~,, J ...
Tracer O~DD 0.744 40
2 Soil PCBs 716 99
Tracer HCB 24,800 99.99
Tracer OCDD 1.49 99.8
-.. -···--· ·-·-··
----------------------------------------
ECO LOGIC PROPRIETARY INFOFvi1ATJON
ECO LOGIC Technolop UpdaJt -Oct, 1995 .Page 4
I
wage input streams arc injected into the react.Or thrOlJgh
several pons mounted tangentially at the top of the
chamber. Special nozzles at0mize liquid wasteS to
accelerate vap0wi.tatlon. The gas/waste mixture is
heated to about 850-C a$ is 1wirls around the outer
healing chamber. The Proce&.9 reactions take place In an
inner chamber and actually we less than one second to
complete at reaction temperature.
The product g~ exiting through an elbow at the wp of
the reactor is routed through a scrubber !iystem. Here
HCI, water, heat, fine particulates, carbon dioxide, and
oon<hlorinated aromatic compounds such as naphthalene
and benzene are removed. The resultant ~rubbed
prod~ gas is a clean dry mixture of hydrogen, methane,
carbon monoxide and other lighter hydrocarbons. This
fll.S Is then either compressed and stored, routed through
the steam reformer or used ilS a sweep gas for the TRM
andSBV.
Storagt of the product gas permits the analy.si9 of large
batches of gas prior to using it as fuel and allows the ·
operation of the system in a "stackless" mode. Should
the product ias not meet the quality criteda established,
there wiU have been no emissions to the environment,
and the gas can simply be reprocesst:d.
The product ga.c; exiting the reactor is continuously
monitored with a chemical ioniution mass spectrometer
(CIMS) as well as other gas analysers. The CIMS Is
capable of accurately monicoring up to 10 organic
compounds every few seconds at concentrations ranging
from percent l~els down to ppb levels . It is u.~d ~ part
of the ECO LOGIC Process to monitor the
concentrations of ctruin compound!i indicative of the
process destruction efficiency. The CJMS readings are
monitored by the proces~ control system and allow for
optimization of' the Process.
Bulk. solids such ~ contaminated electrical equipment,
drums, and debris are decontaminated in the SBV. In
these chambers che r.olids are htated, thereby volatilizing •
any organic contaminants on the surface. These
contaminants are then fed into the reactor in a ~as phase
by the scrubbed recirculation eas.
Liquid wastes arc simply preheated and injected directly
intO the reactor through atomizing nozzles.
Soil and decanted sediment are dee(')ntaminat.ed in the
TRM with the desorbed co1ttaminants being swept into
the reactor. The TRM opet ates as a heau:d ball mill
which vaporiies the water and organic cm11a1nir.ants in
the waste soil/sediment while mechanically worlcing the
solids into a fine granular mooure for optimum
desorption. The water vapour anti organic con'4Jnina.nt.~
are swept into the reactor by a sidest.ream of scrubbed
recirculation gas.
The TRM design currently employed by the ECO
LOGIC Process represenu a significant improvement
from the TDU demonstrated under the SlTE program.
The lab-scale TRM hli achieved exccllt:.nt re=suits and c;m
consistently desorb organic contaminanu in soils and
sediments horn high ppm levels to low ppb levels in a
slngle pas.~. The residual concentrif.tions in the trC4ted
soils are generally orders of magnitude below disposal
criteria. The results of .a number of lab-scale TRM ~
is shown in Table 3.
· CURRENT STATUS
The ECO LOGIC Process h~ been demon.~trated to be
a highly efficient alternative to incim:rntion tor die
destruction and recycling of hazardous organic Wilt.tt".S .
High water content wastes, high mength oils,
solls1sediments and bulk solids can be processed wilh
DREs of at least 99.9999%. Process outpUtS may be
recycled or re-used on-site with no huardous ortanic
residuals being formed. The ability to compre.u and
store product ga.~& me:.i.m that 110 unconuolled air
emissions can occur.
The lab-scale unit i.~ still employed hy ECO LOGIC for
performing treatability studies. This unit i~ equipped
with a TRM for processing soil as well u an SBV for
solid rn.tterials such as tlectrical equipmeri. Treatabilit)-
studies are a coSt-eft't:ctive method of determining the
applicability and effectiveness of Lhe ECO LOGIC
Process to various wastes streams.
ECO LOGIC has been developing this technology since
1986 and is currenlly able to otter the ECO LOGIC
Proccs.~ at a commercial-~e. This SE-2.5 commt:rci..d•
scale unit has a design capacity of 100 to 300 tonnes/day
of coownlnated soil or sediment and 20 to 30 tonne~/ day
of 1& pure organic wa.ue stream . A fully configured
ECO LOGIC PROPRIETARY INFOPMA.TJON
' ECO LOGIC Technology Update -Oct, 1995 Page 5
system, including TRM and SBV, requires an area 200
feet squared to operate including space for internal
roadways and ruging areas:
The first SE-25 commercia1-scale system has been
constru~d and shipped to Australia where it is being
applied to obsolete pesticide residuals and PCB
conraminatoo electrical equipment. A second SE-25 unit
wiJI be utillxed by General Motors of Canada Urnlted to
recycle roughly 300 tonne..~ of PCB contaminated
electrical equipment and 7,500 tonnes of PCS
contaminated settled solids. Dof asco Inc.. a major
Canadian steel manufacturer, ha.c; also contracted ECO
LOGIC to treat a stockpile of PCB contaminated
electrical equipment.
Tne ECO LOGIC Proces.."i is a proven technology for the
de.~truction and rccycl~ of high-scrength oily and watery
wastes as well as soils, sediments and solids.
ECO LOGIC offers a cost-effective ahernath-e to
incineration and can pro,,ride a complete en-site
destruction service for the owners of hazardous organic
wastes.
REFERENCES
[l] WTC New~letter. puhlished by the W:t!!lewaler
Technol~ Centre, Environment Canada, No.2,
March 1992. Contact: Mr. Craig Wardl.i.·N,
Project Scientific Authority . [phone].
[2] Technology Evaluation Report. SlTE Frngram
Demonstration, Risk Reduction Engineering
Laboratory, USEPA, Cincinnati, OH 45263
July 15, 1994. Contact: Mr. Gordon fa·ans,
SITE Project Manaeer. {517) 569-7684 .
Table 3 SUMMARY OF TEST RESULTS FROM THE LAB-SCALE TRM
Waste PCB Grit PCB
Concentration Concentration
Waste Type (p m) (ppm)
Soil (tarry, oily) 39 0.011
Soil (dry, sandy, PCB-spik~d) 440 0 .0039
Soil (dry, sandy, PCB-spiked) 520 0.0016
Sediment (muddy, fine, PCB-spiked) 710 0.028
Sediment (muddy, fine, PCB-spiked) 790 0.0097
Sediment (muddy, fine, PCB-spiked) 750 0.065
Sediment (muddy, tine:) 7.3 0.0029
Sediment (muddy. fine) 8.3 0.0066
Sediment (muddy, fine) 8.3 0.0013
Sediment (muddy, fine) 420 0.0017
Sediment (muddy, fine) 420 0.012
Sediment (muddy, fine) 2000 0.044
Sediment (muddy, fine) 1200 ND {0.01 I)
1
ECO LOGIC PROPRIETARY INFORMATION
.. ., United Statlils
Environmental Protection
Agency
EPA/540/MR-94/504
March 1994
Dernonstration Bulletin
The ECO Logic Thermal -Desorption Unit
Mlddleground Landfill • Bay City, Ml • ELI ECO Logic International, Inc.
Technology Description: Eoo Logie has developed a ther•
mar desorption onit [TOtJ) for th• 1r1atmtl'I! of toil!i contamtnattd
w~h ha?l!Jdou$ organic contaminants. Thi, TOU ha$ been de•
signed to be used in conjunction with Eco Logic's patented Qc\$•
pha.91 chemical reduction reactor. The Eco Logic r9actor is the
subject ol an independent SITE Demonstration (see SITE Bulle-
tin: ~PAl540/MR·931522, SeptemlxJr 1993).
The TDU (,e& Flgt1rfl 1) consists of an flxlernally-heated bath of
molten tin metal, blanketed in a hydrogen ga$ atmosphere. ECQ
Logic otters several reasons for using tin: tin and· hydrogM are
nonreactive; tin's dlilnsity allows soils to float on the s1Jrface of the
molten bath; tin's low vapor pressure prevents evaporation of the
tin lnlo the h;•drogen: mohen tin it a good fluid for heat transfer;
tin is non·to-,;io as a soil contaminant; and tin has been used as a
bath medium in the manufacture of plate glass for many years.
Contarninat~ soil Is co,wey9d Into s hopp9r where &n :!luger
fMd9 the soil into the TOIJ. The ~rew feeder provides a gas seal
Mrwun 1hg outsidlil air and the hydrogen almosphgre inside the
TOU. The auger's variable sp9ed drive provides feedrate control.
Soil insido the TDU floats on top of 1h11 molten tin and is healed
to 600•C, vaporizing the water and organic material. Oecontami•
Sire
SodtJ
H2
Pf'Dpana
Air
~ ~
D9sorbed Gss
TDU
Figvro 1, ECO lcglc lherms/ • d6so,ption imil shown with re•ctor.
I
I
nated soil is removed from the tin bath into a wator-filled quench
tank. The water In the quench tank provides a gas seat betw·,1en
ltie TDU's hydrogen atrnosph'-lre and the outsk!,. air, A scraµer
mechanism removes desorbed soil lrom lhe quench tank Into
drums.
After desorption from the soil, the 0(gani~ contnmlnnntt; are
swept inlo the companion reactor where they undergo gas·ph.i.r.e
. rgduction roactions with the hydro9@n at t11lt.vvlad h1n"lf)flraturas.
· This gas·pha$e reduction reaction tal--,0.5 place with,n Eco VJgic's
spt1eially-<lesigned reactor: a cylindrical ve>Ssel with a hollow
ceramic tube and electric glo-bar heaters. TM re:tclor op1m1!es
in a hydrogen atmosp~ere. Desorb!K1 organics from th~ TDU
enter the reactor and swirl betweon the re.ictn,s sida wall and
the ceramic tuba. By the time thQ mi><ture enters the contro.l tube,
It has been heated to at least 850•C. The reduction reac.1ions
take place as the gas travels up the central tube to the scrubber.
The scrubber removes hfdrogen chloride, hr.1.at, wnter, end fine
particulate matter from the gas strum. When processing low
organic wastes, approximately 9.5% or the hydrogon -rich g.m
recirculates back into the reactor, while tht:1 remaining 5% I~ used
as supplementary fuel for the system's propane•firad boiler. Pro•
Rodrc. G.ts j
Slvdge and Decant
W,1191 8/owdown
Clean Steam
REACTOR SYSTEM
1-/ydf'OctJrbcr:
GC$ (5:<,J
@ ~rir.ted on rtt.?cycled Plp6r
-------------------------------~-------...__, ______ _
eessing waste streams with a high organic content produces
mtJeh more excas!\ gas, which can be compr&$&ed, stor!XI, and
analyzed batore tJse as a supplementary fuel.
The TDU can be transported on a ~Ingle, standard flatbed trailer.
The companion n\actor, scrubber, boiler, and •uxiliery equipment
are mounted on two standard, drop-deck highway trailers.
Waste Applicability: The TDU, whon ~upled with it's com-
panion reactor, is guilable for m~ny wastes Including polychlori-
"at9d biphenyls (PCBs), polycyclic aromatic hydroc~rbons (PAHs),
chlorir,ated dio'Xins and diban2'.ofutans, chlorinated solvents,
chlorbenzenas, and chlorophenols. The TDU is designed to treat
most soil and sludge wastes, including those with a high water
ecntent.
Demonstration Results: The u.s. EPA's Superfund Inno-
vative Technology Evaluation (SITE) Program, in coo~ration with
Environment Canada, the Ontario Ministry c,t the Environment,
and the City of Bay Cky sponsored a demonstration or the Eco
Logic TDU In confunction with Iha Eco Logic raactor systtm at the
Middl9ground Landfill in Bay C~y. Michigan during Novemb.r and
DecembElr 1992. Previous tests of the reactor systtm conducted
during October 1992 demonstrated 99.9999o/. destrvctior'I end
rgmoval 111ffici8ncy on PCB-contaminated water (approximately
4000 ppm PCBs) and oil (24.53/e PC8s).
The TDU test plan called for lhrH analytics! test runs on soils
excavated from the landfill. The soi!s contained approxirnatflly .
1000 ppm PCBs. Tests were conducted urider a TSCA R&D
permit. Run 1, hampered by shakgdown and materiaf3 handling
problems, cauud Eco Logic lo make modifications to th8 syst&m
prior lo Run 2. fttJn 2 was c.onducted with a reduc9d teed through•
put in order to increau soil residence time on the tin bath to
United States
Environmental Protection Agency
Center for Environmental Research lniormation
Cincinnati, OH 45268
Official Business
P•nalty for Private Use
$300
EPl\'540tMR·94/504
&d~quattly hi,at clumps of soil that formed in the :.;yEilem. Run 3
was cancelled du• to TSCA permit time constraints.
The demonstration achieved thA following:
• PCB destruction and r@mova! 8flickmcies (DRE,) tor the TDU
and reactor $ystem combined were 99.9999% for Run 1. Run
2 resultg were Impacted by sarnping and analytical problGms.
• PCB concentrations in the cleaned toil ran;ed belween 8 and
30 pprn.
• Destruction eHicioocies (0Es) for hexachloroben1.ene (ad.;1ed
ag a ~urrogatowasle) rangedlrom i2o/a for Run 110 99.9!il1/. for
Run 2.
• Throughput wa., 180 lb/hr for Run 1 and 55 lb/hr for Run 2.
Er:o L.r;,gic plarlS to modify the ma1.eria!s handling cepebiliti&~ of
the T0U to eliminate clump romiation 1111d increase throughput.
The final report will address oth~r test r&sl•lts, including M
analysls of proce:s!I Input!, lnterrnediata:i, and oulput.!. Sy~tem
reliability, mass balances, costs, and safety will also be ad•
dressed.
For Further Information Contact:
SITE Project Manager:
Gordon M. Evans
U.S. EPA
Risk Reduction Englneoring Laboratory
28 W. Martin L. King Dr.
Cincinnati, OH 45268
(513)-569-7684
BULK RATE
POSTAGE 8 FEES PAID
EPA
PERMIT No. G-35
UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
OFFICE OF RESEARCH ANO oe:ve:LOPMENT
RISK RE0UC,-JON ENGINEE~ING LABORATORY
CINCIN"IATI, OMIO 45.!68
Don Butler
N.C. Superfund Section
P.O. Box 27687
Raleigh, NC 27611
Dear Mr. Butler:
June 15, 1993
A meeting was convened during week of March 8, 1993 for the purpose of
reviewing the data collected during the Agency's SITE Demonstration of the Eco
Logic Process. As a result of this rQview process, I am able to provide you
with a brief overvi~w of the preliminary conclusions as based on our project
objectives. ~ou will find these results summarized below.
Please note that at the present time the
office is experiencing a backlog in procP.ssing
involves the contract which provides technical
Until their backlog is cleared, 1'11 be unable
providing the public with formal conclusions.
following summary will suffice.
Agency's contracts management
contract actions. One action
support to this dEmonstration.
to meet my target date for
In the mean time, I hope the
These preliminary results refer exclusively to the two-part test
conducted on Eco Logic's Reactor Unit. The first group of three te,t runs
involved PCB contaminated water, while the second group of three test runs
processed PCB contaminated oils.
The primary objective of SITE demonstration was to determine the
destruct ion and removal efficiency (ORE) for PCBs. The OR£ measurement
compares the amount of PCBs in the waste input streams to the amount of PCBs
measured in the unit's propane boiler stac~ gases. The systrrn successfully
met our target of 99.9999% ORE for all six runs conducted under both t~st
conditions.
The second objective was to determine the destruction efficienc_y (DE)
for perchlorethylene 1 a predetermined tracer compound . The OE measurement
compares the amount of perchlorethy1ene in waste input streams to the amount
of p~rchlorethylene measured across all output streams. The systEm
successfully met our target of 99.99¾ 0£ for all six runs conducted under both
test conditions.
Our third objective was to examine the ultimate fate of dioxin/furan
compounds which enter the system. The demonstration showed that for each of
rKUM
the six runs under both test conditions, the system achieved a net destruct ion
of those trace amounts of dioxins and furans which were measured in the wa ste
input streams.
If you need further clarification on any of these findings, please don 't
hesitate to call me (513-569-7684).
Sincerely yours,
~~£~ / Gordon M. Evans
SITE Project Manager
Risk Reduction Engineering laboratory
U.S . Environmental Protection Agency
t·'. t U
: ;
ECO LOGIC
Media Release
Toronto, Ontario
t-1-<:UM
TSE Trading Symbol: ELI
f-'. 11
TOXIC CH~M/CllL
SPEC/ALIS rs
For Immediate Release
September 20, 1995
ELI ECO.LOGIC INC. AND GENERAL ELECTRIC CANADA INC.
ANNOUNCE l\'lULTI-PROJECT LEITER OF INTENT
General Electric Canada Inc. and ELI Eco Logic Inc. announced today that. they have em-:red into
a Letter of Intent which estaMishes the framework and key terms for ECO LOGIC to provide PCB
decontamination and processing services to GE for a series of projects.
Dr. Harvey Lee, Manager of Environment, Health and Safety, GE Power Systems C,mada,
• stated: "It is intended that a formal agreement would be entered into for each pro_iect. The formal
agreement for the first multi-million dollar project is now being prepared. We look forward to ECO
LOGIC commencing operations at one of our sites early in 1996."
"The ECO LOGIC Process is a patented mobile chemical reduction process which transforms
material~ such as PCBs into useful products," Dr. Lee said. • A closed-loop process, it p~rmanently
destroys organic contarninanLo; and eliminates uncontrolled emissions. lts development has been carefully
evaluated by GE engineers since 1989. It has also been successfully evaluated for PCB destruction by
the USEPA, the province of Ontario and other regulators and major industrial users. The ECO LOGIC
Process has been proven to meet strict environmental and saf e1y standards and has now been operated
in Canada, the USA, and Australia."
Dr. Douglas Hallett, ECO LOGIC's President, said, "There are a number of advantage~ to the
ECO LOGIC Process. including the ability to treat all types of PCBs, including contarninated soils,
equipmem, liquids and solids, as well as to contain any gases generated. It Wa!t developed to provide
high destruction efficiencies and waste volume capabilities without the e,cp-:nse, technical drawbacks or
emissions of incinerators. The GE projects will involve a variefy of PCBs and PCB~comaminated
materials and will be subject to the normal regulatory approvals process.·
"We are excited about working with ECO LOGIC,•· concluded Dr. Lee. "ECO LOGlC's
technology permits us to pennanently and economically treat toxic c-rganic rnate!"ials in an
environmentally safe manner which has received wide community support where it has been applied."
For furthel' information please contact:
Douglas J. Hallett, Ph.D.
President & CEO
143 Dennis Street
Rockwood. Ontario NOB 2KO
Telephone: [phone]
Facsimile; 519-856-9235
143 Dennis St., Rock\\,ood, Ontario, Canada, N08 2K0
Dr . Harvey R. Lee
Manager. Environment, Health & Safety
GE Power Systems Canada
General Electric Canada Inc.
2300 Meadowvale Blvd. (TPl)
Mississauga, Ontario L5N 5P9
Telephone: [phone]!8
Facsimile: 416-583-4221
Rockwood (5191 85b 95}1
F.:ix (519) 85n-9:?JS
ECO LOGIC
Media Release, ELI Eco Logic Inc.
Toronto, Ontario
TSE Trading Symbol : ELI
Tr .>XIC , '/-lf.1111( At
.,,,rcMt ,srs
For Immediate Relea~e
November 14, 1995
THE ECO LOGIC PROCESS NA.MED BY U.S. ARMY AS POTENTIAL ALTERNATE TECHNOLOGY
The U.S Army has selected ECO WGIC's patented gas-phase chemical reduction process as one ('f three new
technologies which may be capable of safely disposing of chemical agents. A technology review will be.
conducted for the Amty by the U.S . National Research Council's newly-formed Alternative Technology Panel,
The selection v.as made by the U.S. Army Chemical Stockpile Disposal Program which is respo)1sible for the
disposal of chemical agents and munitions at eight sites in the continental United States.
The information wa.s submitted as a concept design for safe disposal cf blister ageut mustard and nerve agent VX
stored !t Aberdeen Proving Ground, Maryland., and Newport Army Ammunition Plant, Indiana, respectively ,
within the time frame allotted by the Chemical We.apons Convention. Chemical demilitarization is ma11dated by
intemational treaty between the U.S .A. and Russia to be completed by the year 2004.
"We ar~ looking at processes that would enable us to do a better job of the business at hand aud do it with less
risk across the board," said Maj . Gen. Robert D. Orton, U.S. Army Program Manager for Chemical
Demilitarization . "In order to minimize the cumulative risk to the workers, public and rhe environment. i! must
be done with very little delay in terms of the current program. The challenge for all of us in this busine.~s is to
continue to look widely and broadly for better ways of doing what we're charged with doing .''
Dr . Douglas Hallett, President and CEO of ECO LOGIC. stated, "This represents a major breakthrough for
our company into Ute U.S. defense industry and the recognition by the U.S. Army of a new niche application for
the ECO LOGIC Process. "
EU Eco Logic Inc. solves toxic chemical problems in a cost-effectiv~ manner with i11novati\'e techuology. The
£CO LOGIC Process is a proprietary, mobile, chemical reduction technology for on-site conversion of organic
h&zardous wastes into reusable or disposable products. This lower-cost non-incineration process has higl1 public
and regulatory acceptability. The worldwide market includes PCBs , electrical equipment, comaminared soil-;,
chemical warfare agents, petrochemical wastes; certain radioactive mixed wastes, and municipal sludge.
For further informalion please contact:
Douglas J. Hallett, Ph.D.
President & CEO
ELI Eco Logk Inc.
143 Dennis Street
Rockwood, Ontario NOB 2KO
Telephone: [phone]
Facsimile: (S 19) 856-9235
J .l.) Ot•1",i~ S1., Rockwood, Onlario, Canacfo , NOB 1KO
Rockwood (5 1 'Ii ~~t,-~1_:;n:1 r,,>: :'> 1111 g-;;,.<J~•:;
f-f<:UM P. L3
TOXIC CHEMICAL
SFECIA.l.lSTS
ECO LOGIC
For Immediate Release
Toronto. Canada: CON Tradine Symbol: ELII April 6, 1~95
ECO LOGIC and DOFASCO INC. ANNOUNCE COl'-ITRACT
Dofasco Inc. and ELI f.co Logic Inc. announced today they have entered into a contract
for ECO LOGIC to process PCB-contaminated equipment at Sherman Mine in Northern Om.ado.
The project will consist primarily of the remediation of approximately 280 tonnes of PCB askarel
and elecuical transfonners. The ECO LOGIC Process will transform the PCBs into safe,
reusable or disposable products and permit the recycling of the transformer carcasses .
John Macnamara, of Dofasco, stated: "We arc pleased to be one of lhe first companies
to rc:tain ECO LOGIC to process PCB-contaminated material. Thi~ project will take place at
a Northern Ontario mine site and will demonstrate the ability of ECO LOGIC's iru>ovative
mobile technology to set up and operate at a remote site. The chemical reduction process from
ECO LOGl C provides complete, on-site destr\lction of hazardous organic wastes . It transforms
materials such as PCBs into useful products. It permanently destroys organjc contaminants in
a closed-loop process and eliminates uncontrolled emissions. We are in tl1e process of filing an
application with the Ontario Ministry of Environment and Energy for a technology demonstration
permit."
Douglas Hallett, ECO LOGIC's President, said, "There are a number of advantages to
the mobile ECO LOGIC Process, including the ability to treat all types of PCB wastes, including
conLDminated equipment, liquids and solids, as well as to contain any gases generated. It was
developed to provide high destruction efficiencies and waste volume capabilities without tl}e
expense, technical drawbacks or emissions of incinerators."
ELI Eco Logic Inc . is an Ontario-based corporation that soJ.ves toxic chemical problems
in a cost-effective manner through sound science and innovative technologies, such as the
ECO LOGIC Process.
For further inf onnation, please contact;
Dofasco Inc. or
P. 0. Box 2460
Hamilton, ON L8N 315
Attention: John Macnamara
TeJephonc; 905-544-3761
Facsimile: 905-548-4249
143 Dennis St., Rockwood. Ontario, Canada, NOB 2KO
ELI Eco Logic Inc.
143 Dennis Street
Rockwood, ON NOB 2KO
Anention: Dr. Douglas Hallett
Telephone: 519~856-9591
Facsimile: S 19-856-9235
Rockwood 1519) P.56-95.9!.
Fax 1519)6%-9.235
c :LEANUP .:LEYELS ro:R
:DIOXIN
· CONTAMINATED SOILS
Joel S. Hirschhorn
Hirschhorn & Associates
2401 Blueridge Ave., Suite 411
Wheaton, MD 20902
[phone]
FAX [phone]
August 1996
This paper is being submitted for publication
in a leading peer reviewed environmental journal.
Abstract
CLEANUP LEVELS FOR DIOXIN CONTAMINATED SOILS
Joel S. Hirschhorn
Hirschhorn & Associates
2401 Blueridge Ave., Suite 411
Wheaton, MD 20902
EPA's use of a 1 part per billion level for dioxin contamination in residential soils is shown
to be too high and not protective of public health. It was derived in a 1984 cancer risk assessment
by another federal agency, but it is inconsistent with risk-based levels of2 to 4 parts per trillion
obtained by using EPA's risk assessment methods. EPA has called the 1 ppb level a policy-based
leve~ which correctly distinguishes it from a risk or health-based cleanup standard. The 1984
assessment is shown to have shortcomings, and its policy recommendation of using 1 ppb was not
consistent with its scientific conclusions and caveats. For over a decade dioxins have been lefi in
soils at levels posing health risks and sometimes that EPA is legally required to address.
Moreover, noncancer effects have been ignored, but recent work has shown them to support
action at levels much lower than 1 ppb. To protect public health and be consistent with current
scientific f!owledge and other EPA policies new EPA policy guidance for dioxin soil cleanups is
needed, aj d key elements are presented.
I Key words: dioxin, risk assessment, soil cleanup, Superfund
Introduction
For soil cleanup decisions at Superfund sites, EPA has used 1 ppb of dioxin contamination
for over a decade. At issue is whether this level is protective of public health. Although given
originally as the concentration of the most toxic dioxin isomer, it now is given as toxic equivalent
(TEQ) concentration. TEQs are obtained from using toxic equivalency factors (TEFs) for ce11ain
dioxins and furans that convert or normalize concentrations to equivalents for the toxicity of
2,3, 7,8-tetrachlorodibenzo-p-dioxin (TCDD), which has a TEF of one.
Surprisingly, even though there has been remarkable attention to and publications on
dioxins, there has been no detailed examination of the widely used 1 ppb cleanup level. This
analysis provides new information about the scientific basis for the 1 ppb leve~ alternative values
obtained by using EPA's methods, new information from the Agency for Toxic Substances and
Disease Registry (ATSDR), and information on EPA's use of 1 ppb in the Superfund program
and how its use compares to other EPA policies.
1
Source of the 1 ppb value
A paper published in 1984 by Centers for Disease Control (CDC) staff presented this-
value, 1 although the figure had probably. been disseminated within government in 1983. CDC
performed a cancer risk assessment that was based on doses for 1 o-6 risk, and exposure doses for
residential exposure to contaminated soil. CDC said that 1 ppb was "a reasonable level at which
to begin consideration of action to limit human exposure for contaminated soil."
For Superfund decisions, a 1989 EPA memo has been cited by EPA as setting a policy of
using the 1 ppb figure as an action or health concern level. 2 The memo cited the CDC paper as
the source of the 1 ppb figure. The memo was for a particular Superfund site decision and was
not issued as EPA policy guidance. Importantly, the memo noted "that 1 ppb does not represent
a fine line between safe and unsafe conditions as the term 'action level' implies." But it has been
used in exactly that way. The memo did not include EPA's 1985 health assessment for dioxins3
among the references it cited. EPA still uses the cancer potency obtained in its 1985 study.
In 1987 EPA released the results ofits National Dioxin Study,4 which included soil
contamination data for some Superfund sites, but the laboratory testing detection limit was only 1
ppb for about 75% of the sites, meaning that levels below that were largely unaccounted for, as if
they were unimportant. If dioxin TEQ levels below 1 ppb are of health significance, then rather
than using EPA's method 8280 for dioxin testing which has a generic detection limit of 1 ppb,
only method 8290 with one of 1 ppt is appropriate. The continued use of 1 ppb as a cleanup
standard has sometimes resulted in the less accurate laboratory method being used, leading to
unreliable data for lower dioxin levels.
EPA risk assessment
EPA has developed risk assessment procedures and established presumptive numerical
values for key parameters. EPA Region 3 issues a widely used set of risk-based concentrations,
based on 1 o-6 risk, including values for residential soil ingestion. 5 Its value for TCDD is 4 ppt.
Changes in the parameters used in risk calculations can change this value, even for what
seems as the same basic residential exposure and risk level. For example, an EPA contractor for
the Escambia Treating Company Superfuud site, Pensacola, Florida, calculated a soil level of 2
ppt TEQ for residential exposure and 10·6 risk. This figure reflected three exposure pathways of
ingestion, inhalation, and dermal exposure, that was appropriate because soil in au adjacent
community had been contaminated by dioxin for many years. EPA's 4 ppt is for ingestion only
and is more appropriate for soils on a cleanup site. The state of Georgia publishes a value
corresponding to 4.8 ppt, following EPA risk methods, but probably with some minor change in
one or more parameters.
Another issue is exposure to other site contaminants, especially PCBs, because they are
related to dioxins in molecular structure and toxicity, but EPA has not yet determined TEFs for
2
them. EPA has said that PCBs could double or triple TEQ values, and a leading dioxin expert has
said that dioxin TEQs should be doubled to account for contributions by PCBs.6 Recent research
supports this view of PCBs. 7
Difference between EPA and CDC soil levels
All risk assessments use the same basic method. But they can and are used and presented
in different ways. EPA's value of 4 ppt was obtained by asking the question: what level of dioxin
contamination in soil corresponds to a 1 o-6 cancer risk, assuming various parameters for ingestion
from residential exposure? But CDC asked: assuming a level of 1 ppb TCDD in soil and various
exposure parameters, is this level of health concern? There are two basic components of risk
assessment: (1) determining an uptake dose from the contaminated soil, and (2) determining a 10·6
risk-based dose from toxicity data. EPA used one set of toxicity data, while CDC used that one
plus another. CDC used a range of 10·6 doses (.028 to 1.428 pg/kg-day), and the low dose came
from the toxicity data also used by EPA, but the highest doses came from the other data. Tue
dose range allowed a risk range to be calculated. The lowest cancer dose equated to a risk of 2.3
x 10·5 for 1 ppb dioxin contamination and various exposure assumptions.
However, the lower limit dose does not correspond to the value obtained in 1985 by EPA
and still used, which was .006 pg/kg-day. This smaller dose resulted from use of a higher toxicity
or cancer potency than most of the data used by CDC. This lower EPA dose, together with
CDC's exposure assumptions, results in a risk of 1.1 x 104 for 1 ppb dioxin.
CDC 's exposure model used assumptions to obtain uptake dose that merit attention. For
example, it assumed that the 1 ppb level might be in 100%, 10% or 1 % of soil, and that some soil
had no dioxin contamination. This is like assuming that 1 ppb is a maximum value, but not
necessarily the average level over an area. EPA data are normally average levels. CDC assumed
a 12 year half-life for TCDD in soil, meaning that exposure over decades would not be to the
initial level, but to much lower levels. Remarkably, the same CDC paper also said that 'The half-
life of TCDD in soil is not known." A brief discussion noted the degradation by ultraviolet light
required certain chemical circumstances, and that biodegradation would occur "at a very slow
rate." Although there is no consensus on soil half-life for dioxins, the best estimate is 25 to 100
years.8 CDC's assumptions lowered uptake dose and health risk.
CDC used higher ingestion rates of soil for children than EPA does, but the level for
adults was the same. Various assumptions were used for dermal and inhalation uptakes, not all of
which agree with EPA values. Tue overall impact of all CDC's assumptions was determined.
EPA's smaller 10·6 dose was used while maintaining the other parameters the same as CDC used.
Tue result is 9.4 ppt for TCDD in soil. Because this is greater than the 2 ppt obtained for a
similar multipath exposure by using EPA's procedures, all of CDC's data reduced total exposure
and dose, and therefore risk, as compared to EPA's method.
CDC concluded: ''the excess lifetime cancer risk for exposure to residential soil with a
3
peak TCDD contamination level of 1 ppb ranges over 4 orders of magnitude, from above 10-5 to
below 10-8." Over time, EPA and others have ignored CDC's risk range for 1 ppb and, especially,
that risks lower than 10-5 resulted from a cancer potency lower than that used by EPA and less
conservative exposure assumptions. IfEPA's cancer potency and exposure assumptions are used,
an average concentration of 1 ppb has a risk of 5 x 1 o-4, which is high. The 1 ppb level is not a
I o-6 risk based concentration. It is a value that CDC associated with a range of I o-6 risk cancer
doses, all greater than EPA' s value, and exposure conditions that in total resulted in less dioxin
uptake than with EPA's exposure parameters.
CDC's policy recommendation
The CDC statement that I ppb ''is a reasonable level at which to begin consideration of
action to limit human exposure for contaminated soil" was given in the paper's abstract. But in
the paper's summary, CDC said ''we have concluded that residential soil levels greater than I ppb
TCDD pose a level of concern." These are two very different statements. The second one was a
clear scientific conclusion that is compatible with EPA's value of 4 ppt, because it did not specify
a safe-unsafe boundary, but only an unsafe level. The abstract's statement was a policy
recommendation for government to use a I ppb level to decide whether or not to take action,
such as soil cleanup or relocation of residents, that EPA adopted. As the above analysis has
shown, the policy statement is inconsistent with EPA's scientific findings and risk assessment
procedures, is not fully supported by CDC's findings, and has resulted in the incorrect belief or
assertion that levels below I ppb are not of health concern.
The CDC paper had other related statements, including "a soil level of 1 ppb TCDD in
residential areas is a reasonable level at which to express concern about health risks." ( emphasis
added) This phrase is not equal to the policy recommendation of "at which to begin consideration
of action." Another CDC statement was "Although from these calculations levels ofTCDD
below 1 ppb are, for practical purposes, considered not to reach a level of concern, several
additional considerations related to the risk assessment calculations should be pointed out to
decision-makers involved in risk management." In fact, the paper had several critical caveats,
such as acknowledging "insufficient information about exposure of people to soil, and insufficient
information about intake ofTCDD by humans from such soil." Also, ''whether a certain level of
TCDD in soil will give rise to concern has to be evaluated on a case-by-case basis." No such
caveats accompanied the abstract's policy recommendation. Nor did they suppo1t use of I ppb as
a presumptive cleanup standard.
The CDC study had been conducted because of the highly publicized dioxin contaminated
sites in Missouri that EPA' s Super.fund program was addressing in a highly politicized
atmosphere. CDC was charged with determining ''what level represented an unacceptable risk to
the population living in these contaminated areas. "1 However, before the CDC risk assessment, at
the end of 1982, CDC had already issued a warning that Times Beach should be completely
evacuated on the basis of soil contamination data. In other words, CDC was asked to do what
ATSDR was subsequently created for. If CDC had said that contamination levels below 1 ppb
4
posed a health concern, EPA's decisions on soil cleanup would have been greatly affected, and
costs would have been much higher.
There would not have been an impact on relocation, because EPA had decided in early
1983 to buyout all residents that had been supported by the CDC warning several months earlier.
Tue Missouri buyout was seen as an attempt by EPA to "reverse the agency's tarnished image,"9
because at the time EPA was in turmoil, under intense public scrutiny, and top political appointees
were dismissed or resigned. Later, attention shifted to soil cleanup. In 1986, Syntex attempted to
get EPA to increase the soil cleanup level from 1 ppb to 10 ppb to save 65% of cleanup costs that
it and other companies were responsible for. 5 In fact, the uncertainties and caveats in the CDC
paper could be used to support such an effort, making 1 ppb seem like a political compromise.
EPA's desire to have companies pay for Superfund cleanups has conflicted with reducing the
dioxin cleanup level below the CDC figure. In 1988 EPA used the l ppb level in its decision for
Superfund cJeanup at Times Beach, Missouri. It set the stage for EPA's dioxin soil cJeanup level
becoming policy-based rather risk or health-based.
Noncancer health effects
A recent paper by ATSDR staff addressed noncancer health effects and possible levels of
dioxins for cJeanup decisions. 10 This is important, because over the past few years there has been
increasing recognition that noncancer health effects of dioxins may be more important than cancer
impacts. For example, a recent successful environmental book said "dioxin acts like a powerful
and persistent hormone that is capable of producing lasting effects at very low doses -doses
similar to levels found in the human population .... Dioxin and dioxinlike PCBs are known to affect
the immune system as well as many parts of the endocrine system."11 The ATSDR authors noted
that "recent studies suggest that noncancer end points may be more sensitive indicators of dioxin
exposure," and derived a value of 40 ppt for chronic exposure of children, which is called an
EMEG, or environmental media evaluation guide by ATSDR EPA has also used a childhood
only basis for noncarcinogenic soil contaminants. 12
The authors also concluded that: "No absolutely safe exposure (i.e., above zero) can be
identified." Tue cancer dose-response models used by EPA and CDC (i.e., linear multistage) also
assume that even one molecule can result in cancer. 13 Although a recent analysis, using EPA' s
dioxin toxicity data, showed only a 10-15 cancer risk from one TCDD molecule,14 public concerns
about dioxin exposure are increasing, in large measure because of noncancer effects.
Moreover, the ATSDR authors acknowledged the need to address incremental exposures,
resulting from multiple, background, and past sources of dioxin exposures. They noted that
"ingestion of homegrown vegetables and fruit, and dermal/dust inhalation exposure of those
working in the garden must be considered" and that "special attention must be paid to the
exposure of children playing on contaminated soil." In other words, depending on varying
background exposures for different people in different locations, an additional exposure from a
cleanup site may be more or less important in causing new or additional health effects. Also,
5
there has been recent findings of synergistic estrogenic effects among PCBs and pesticides which
strongly suggest similar interactions with dioxins. 15 All such conditions "suggest the need to
further lower the TCDD levels in soil in order to lower the total exposure," according to the
ATSDR authors. They recommended that although the 1 ppb level "may be appropriate guidance
value ... to the extent that parameters of exposure and/or human factors would suggest the
existence of at risk or wlnerable population groups, alternative values such as these outlined in
this paper should be considered."
The 1995 ATSDR Public Health Assessment for the Escambia site used an EMEG of 50
ppt for dioxin TEQ in soil. But ATSDR said ''The levels of dioxin-TEQ in off-site soil are
unlikely to cause noncarcinogenic health effects." even though the report gave the maximum level
of 950 ppt from 1992 testing. The report also said ''Because the cancer risk in people from
exposure to dioxin-TEQ is currently under scientific review, we do not know what carcinogenic
health effects are likely." But the uncompleted EPA dioxin reassessment did not nullify the EPA
cancer risk information that EPA itself has continued to use, including for the Escambia site. The
50 ppt value was ignored by EPA, which only focused on cancer risks and the l ppb level. This
author knows of no Superfund site where EPA has used noncancer effects of dioxin to set or
influence cleanup levels or other actions, such as relocation of residents.
Background levels and incremental risks
There is a critical need at Superfund sites to determine the local background level of
dioxins in soils and the level of dioxins in blood lipids in people plausibly exposed to site dioxins,
especially when contamination is found in residential soils. Background data serve two purposes.
One is to decide whether soil contamination is significant. The other to determine whether an
exposed population has prior or multiple exposures. There is no scientific support for dismissing
dioxin contamination below 1 ppb as merely background concentrations, an approach often used
by EPA, unless data are obtained from control samples at some distance from the site. Using data
from locations near a cleanup site or on it, which is sometimes done, provide overly high levels
that are not true background levels. Higher than normal background soil and blood levels for an
exposed population provide the basis for lower dioxin cleanup levels, either on the Superfund site
or offsite, or both.
Background soil levels of dioxins in North America vary widely, from 2.26 to 13 .66 ppt
TEQ, according to EPA.16 This range is not surprising, because some geographical areas, even at
significant distances from point sources, have been impacted by air deposition of dioxin
contaminated particles from waste incineration, industrial manufacturing, and other sources.
Also, EPA assumed nondetects equal to half the detection limit, which is EPA's procedure for
risk assessment,17 but is not necessarily used when data are reported. A study on dioxin
background exposures in the United States assumed only a .96 ppt TCDD soil level, compared to
EPA's average of 8 ppt TEQ.
The background level issue and paying attention to multiple exposures to dioxin were
6
examined in a 1985 EPA analysis that focused on findings of dioxin soil contamination in
Midland, Michigan, where Dow Chemical operated a plant that had produced pesticide chemicals
having dioxin contamination and incinerated chemical wastes. 18 The EPA risk assessor argued
that 1 ppb was probably not appropriate to evaluate the findings. EPA's data showed the average
level ofTCDD (TEFs were not set until 1989) to be 48 ppt in Midland residential and public
access soils, as compared to 2.4 ppt in Middleton, Ohio, a comparable industrial city. The
average level around the perimeter of the Dow Chemical plant was 327 ppt, compared to 2.2 ppt
arow1d a steel mill in Middleton. Dow Chemical had obtained its own data on soil levels in a
number of industrial cities and reported an average of 2.2 ppt. The EPA risk assessor argued that
the Midland levels were not normal background levels, and were especially significant because
many residents had been exposed as workers at the Dow Chemical plant, that people had been
exposed to soil and air dioxins for decades because of release from the facility, and that they bad
eaten homegrown vegetables and fish from a local river that were probably contaminated by
dioxins.
Here was a specific case where site specific circumstances showed the need to see levels
below 1 ppb as of health concern, and to use a lower level for cleanup and relocation decisions.
Like the Missouri situation, here too there was a political dimension, because in early 1983 tb,ere
was a controversy involving a senior EPA official, forced to resign, based in part on actions that
allowed Dow Chemical to affect EPA's decisions on dioxin contamination in Michigan.8 It is
clear that the Missouri and Midland cases were the precedents for EPA's use of the 1 ppb level as
a policy-based figure.
EPA' s actions for the Escambia site in Pensacola also illustrate problems related to
background levels. In 1995 soil sampling was done in the residential community close to the
Escambia site, part of which is adjacent to the Escambia site and part a little more distant and
even closer to another Superund site (Agrico Chemical). Samples were also taken from four
areas outside this immediate community but only slightly further away. EPA has acknowledged
levels of dioxin contamination of health concern only in a small portion adjacent to the Escambia
site, where the average level was 587 ppt TEQ, but where several locations bad levels above l
ppb. The area a little further away from the Escambia site had an average of 70 ppt, and the next
more distance area 7.3 ppt. In the neighborhood closer to the other Superfund site, that is more
distant from the Escambia site, the average was 12.4 ppt. For the four areas outside the
residential community, a school yard had 7 ppt, a baseball field 7.5 ppt, a vacant lot 22. 7 ppt, and
a residential yard 7.8 ppt.
EPA's position was that all the areas, except the one adjacent to the Escambia site (where
the 1 ppb level was exceeded) did not pose health risks and that they had not been impacted by
the Escambia site. No data were obtained, however, to determine background levels in the
Pensacola area. Nearly all dioxin levels were above the 2 ppt determined for residential exposure
and 10-6 risk, including two areas where children spent time (the baseball field and school). It
should also be noted that some residents were exposed as workers at the former Escabia
operation, that the dioxin contamination of the residential soil had initially occurred many years
7
before the site entered the Superfund program, that an EPA removal action that excavated au
enormous amount of contaminated soil and piled it on the site had probably caused some releases
of dioxin, that soils were contaminated by several other highly toxic chemicals, and there were
pervasive health problems in the community. Thus, the issue of incremental dioxin risk was
relevant as evidenced by an ATSDR Health Consultation for the Escambia site prepared in 1992
and its review by the ATSDR Health Activities Recommendation Panel. Because of "likely"
worker exposures at the operating wood treating company and because "off-site exposures may
have occuned," the panel recommended a health evaluation of residents living the site. It was to
include physical examinations and laboratory tests. These were not implemented, however. The
testing for dioxin in blood lipids would have provided important data regarding past exposures to
dioxin among residents.
A recent study revealed the proper use of offsite control soil samples to obtain
background levels. 19 Interestingly, the average background TEQ level was higher than the
cleanup site's level, and both were very low (less than 3 ppt). The backgroun.d levels were
explained as resulting from the impacts of traffic on a major highway on an otherwise rnral area.
The data supported the conclusion that the cleanup site was not contaminated by dioxins.
Prospective versus retrospective exposures
Dioxin risk assessment work has focused on prospective residential exposures and
whether residual soil levels after cleanup would pose unacceptable health risks. Oddly, however,
in many cases dioxin contamination is found in residential soils where people have already been
exposed to the levels found. While the prospective approach is valid for cleanup sites themselves,
that might become residential areas, the retrospective approach accounts for additional
incremental dioxin risk for dioxin contaminated residential areas with exposed populations.
CDC's work for Missouri was such a situation, yet its analysis was only prospective.
Instead of using a half-life to calculate lower dioxin levels for future exposures, it should have
worked backwards to obtain higher levels for the people exposed to the soil in the past. As in the
Missouri, Midland, and Pensacola cases, for many situations the retrospective approach is
necessary, and even EPA's levels of 2 to 4 ppt are not necessarily protective when additional
incremental dioxin risk is considered.
Consistency with cleanup levels for other site contaminants
At most Superfund sites, soil contaminants are designated as Contaminants of Concern,
and EPA sets cleanup levels as preliminary or final remediation goals. In many cases, these are
based on l o-6 risk and residential exposure. In those cases, when dioxins are also site
contaminants, the issue arises as how EPA can use 1 ppb when according to EPA's own risk
numbers the I o-6 risk is 2 to 4 ppt. Reasonable people question how the government can use the
l o-6 risk level for every toxic chemical except dioxin, that EPA acknowledges to be the most toxic
chemical. Moreover, if some soil with up to 1 ppb dioxin remains after cleanup, then residual
8
risks are I 0-4, negating the benefit of cleaning up the other contaminants to 1 o-6 risk levels.
EPA soil screening values
EPA has established generic soil screening levels for 110 chemicals, for use in the
Superfund program. 10 These are based on 1 o-6 risk and residential soil ingestion exposure. They
can se1ve as preliminary or final remediation goals, unless site specific information is used to
support other levels. But no value was presented for dioxin. The explanation from EPA is that a
policy decision had already selected 1 ppb, and that EPA' s dioxin reassessment is ongoing.
EPA's use of the 1 ppb level
A good example of the current problem is an EPA study in 1995 that tested residential
area surface soils in a small town, Tifton, Georgia, with a number of toxic waste sites. EPA
dismissed the findings of dioxin in all 14 samples solely on the basis that they were below 1 ppb. 20
This author's analysis of the data found that the sample locations could be divided into three
groups, based on distance away from the Marzone/Chevron Superfund site. It was found that the
5 residential soil samples closest to the site (about a quarter mile or less) had an average dioxin
TEQ level of 65.2 ppt (with a maximum of 120 ppt). For the three locations fiuther away the
average was 5.9 ppt. For the 6 locations about one-half to a mile ·away the average was 2.6 ppt.
However, the detection limits were unusually high for the 8290 method, suggesting systematic
underestimates ofTEQ dioxin. This was compounded by the procedure of ignoring all
nondetects. EPA guidance is to use onehalf the detection limit. Correcting the data resulted in
TEQs for the three zones given above of 66.8, 14.4 and 10.5 ppt, with increasing distance from
the Superfund site. This is strong evidence that dioxins had migrated from the site into the
surrounding community by means of airborne transport of dioxin contaminated soil particles (from
the cleanup site or from the original industrial operation at that site). The corrected TEQs,
moreover, indicate levels of health concern at all distances from the cleanup site.
Although ATSDR reviewed the data for EPA, it simply said that the levels found were
below health concern, without providing any explanation or analysis, and ignored the EMEG of
40 ppt for noncancer effects, exceeded at three locations near the site. No problems with the data
were noted. Neither EPA or ATSDR noted, at the time the study report was released, that no
testing of dioxins had ever taken place at the two toxic waste sites fitting categories known to
likely have dioxin contamination (pesticide and wood treating sites).
Subsequently, when testing showed widespread dioxin contamination at the
Marzone/Chevron site, where EPA had previously established pesticide cleanup levels for 10-6 risk
from residential exposure, EPA attempted to dismiss all findings below 1 ppb, choosing to focus
on one area with levels well above 1 ppb (maximum of 3 ppb ). For these test results onehalf
detection limits were used for nondetects. The position that dioxin contamination in the main
former pesticide factory surface soil was just background, and not a result of pesticides, was
inconsistent with the average level of 45 ppt TEQ (maximum of276 ppt), findings of dioxin in
9
subsurface soil (greater than surface soil levels) and chemical storage tank contents, and the lack
of measming background TEQ in the Tifton area. Where subsurface dioxin levels were
substantially greater than in surface soils, levels of site pesticides were also correspondingly
greater than in surface soils, providing additional support for concluding that dioxin
contamination was caused by some pesticides handled at the site.
In 1996, EPA Region 4 conducted an analysis of dioxin cleanup levels at Superfund sites
(unpublished). Over 12 years, 20 sites used the 1 ppb level, and 6 used levels greater than 1 ppb
and 7 less than it. In three cases the cleanup levels were low, between 4 to 7 ppt, at about the
10-6 risk level. Nevertheless, EPA officials often state that it would set a dangerous precedent if a
value less than 1 ppb was used. The "danger" is economic, namely that a lower cleanup or action
level increases the costs of cleanups and relocations, and might affect decisions already made and
cause more cleanup. New residential areas built 011 soil previously cleaned up to 1 ppb would be
vulnerable.
Legally, it is clear that the 1 ppb value is, at best, only guidance, but it was never issued by
EPA as guidance. At various times EPA has stated that the 1 ppb level is an action level, a
screening level, and a level of health concern. It is not, however, a rigid cleanup standard having
statutory or regulatory standing. Yet as concerns about Superfund costs, funding and liabilities
have increased, EPA's desire to impose the 1 ppb level has increased. The 1989 EPA memo had
cited the important caveats of the 1984 CDC paper about making decisions on the basis of site
specific circumstances. A 1992 EPA memo on the strategy to be used in the Superfund program
for addressing infonnation from the agency's dioxin reassessment made no mention of the
program's use of 1 ppb.21 Ways in which decisions could be reopened were presented and a
commitment was made to "use the best science available in making its decisions." But the proper
policy statements by EPA have not resulted in retrenchment from EPA' s use of 1 ppb as the
presumptive dioxin cleanup standard. Only a few Superfund site decisions have used lower levels,
and they were not major sites.
Data on other types of cleanup sites, federal and state, are difficult to obtain. But a
cleanup at the Naval Seabees Center, Gulfpoint, Mississippi, used a dioxin cleanup level of 5 ppt
to remove contaminated soil with about 100 ppt dioxins. And the state of Florida is using a 7 ppt
level for a 10-6 risk and asking that it be used for the cleanup of the Coleman-Evans Wood
Preserving Superfund site. If a state has some type of standard, requirement or crite1ion for a
lower dioxin cleanup level, than EPA can be compelled by statute to use it.
Legal violation
The 1 ppb level corresponds to a risk over 10-4 according to EPA's risk data. Under the
federal National Contingency Plan (NCP) governing the Superfund program, such risks require
EPA action. There is some confusion over what current risk requires EPA action versusfuture
risk and cleanup goals, because of the NCP's risk range of 10-4 to 10-6• But NCP language, EPA
guidance, and recent General Accounting Office reports made it clear that cunent risks above 10-4
10
require EPA action,22 usually by taking a removal or emergency action, or an interim remedial
action. EPA does not have to achieve future residual risks of 10·6, but under the NCP if it does
not it must ex.plain why. Usually, the reason is non-residential exposure. Using EPA's figure of 4
ppt, 10·4 risk equates to a soil level of 400 ppt (appropriate for cleanup site soils), and using 2 ppt
it is 200 ppt (appropriate for residential soils). In other words, when data reveal levels above
these, EPA is legally required to take action. Conversely, when EPA ignores levels below 1 ppb
and above these lower levels, it is not complying with the NCP.
At the Escambia, Pensacola site in 1992, after EPA had completed a removal action that
consisted of a massive excavation of contaminated soil to protect groundwater, it tested soil in a
few residential backyards immediately over the site's fenceline and found dioxin, ranging from 34
to 950 ppt TEQ with an average of 316 ppt. It used a sample for background very near these
locations and on the Escambia site itself that had 14 ppt. Three years later, EPA obtained more
dioxin data showing even higher levels in residential soils (average of 587 ppt TEQ and maximum
of 3 ppb in the area closest to the site). Four years after the original evidence of dioxin
contamination in the residential area, EPA had not taken any action, such as soil removal, soil
covering, or relocation of residents to protect public health against risks greater than 10·4_ The
residents were not helped by ATSDR's Public Health Assessment in 1995 that raised no concerns
about dioxin.
Treatment technology
It is also relevant that in 1994 EPA established w1iversal treatment standards as part of its
land disposal restrictions program under the 1984 Hazardous and Solid Waste Amendments. The
treatment standard for TCDD is 1 ppb, which apparently was taken from the policy-based level of
1 ppb for cleanups. This standard can be applied to technologies used to detoxify dioxin
contaminated soil. It provides a disincentive for achieving lower levels. It also suggests problems
because ofland disposal of soils with dioxins at lower concentrations that pose health threats.
EPA's original concerns in the 1980s about cleanup costs, especially if treatment
technology such as incineration was used, are less warranted today. There are more technologies
than ever, including BCD dechlorination developed by EPA and licensed to several companies
that have commercialized it, a Canadian technology that destroys dioxins, and several commercial
solvent separation technologies. 23 It is possible to achieve residual levels to low ppt levels.
Increasing competition has reduced unit costs. People concerned about dioxin exposure have
learned about these newer technologies.
Dioxin cleanup and risk management policy
Since the mid-l 980s EPA has used an increasingly inconsistent and technically indefensible
basis for decisions about dioxin contaminated soil. The 1 ppb level was based on a risk
assessment by CDC that had deficiencies and to some extent misrepresented its results to present
a simple policy decision rule with enormous economic implications. There was considerable
11
demand for that dioxin cleanup level in the mid-l 980s. Now, however, there is no credible
scientific, health based, or logical defense for using the 1 ppb figure. The translation of CDC's
risk assessment results into a Superfund action level and EPA's initial uses ofit occurred during
the aftermath of the 1983 backlash against the environmental policies of the Reagan
Administration. But many senior EPA managers still believed in those policies, and they
established a policy-based dioxin cleanup standard that has prevailed.
Changing to a scientifically credible health-based dioxin cleanup level has been seen by
subsequent EPA managers as threatening. Rather than focusing on health risks, they manage
bureaucratic risks. Lower dioxin soil cleanup levels could result in demands to reopen past
cleanup decisions that in combination with more stringent cleanup decisions would require higher
federal appropriations for the Superfund program at a time when they are being decreased. Yet
this problem only worsens with time as more decisions are based on 1 ppb. Concerns about
cleanup costs are valid, especially by government officials, but using 1 ppb that poses health risks
as a solution is not viable public policy.
Another concern of EPA managers is that use of a lower dioxin cleanup level could affect
regulatory permitting and public acceptance of various industrial and waste management facilities.
This raises a conflict between protection of public health and concerns about impacts on sources
of dioxin, such as industrial and municipal waste incinerators. As Silbergard and deFur observed,
"much of the continuing delay by government 111 implementing comprehensive management of
[dioxin] risk arises not only from scientific uncertainty but also from the politics and economics of
controlling specific dioxin sources."
Au attractive delay strategy for Superfund managers is waiting for EPA's final dioxin
reassessment, because it is commonly understood it will take years to complete. Their risk
management means letting successors inherit this problem. The final report is not likely to
remove the fundamental problems with the 1 ppb level. The dioxin soil cleanup issue has been
successfully kept at the Superfund program level, allowing EPA to ignore its inconsistencies with
larger agency goals and commitments. EPA's continuing use of 1 ppb, however, m1dermines its
goals of using good science, common sense, and risk management to improve decisions and
public confidence. Ultimately, there are institutional risks and penalties that can only be
minimized by taking the initiative to correct the dioxin cleanup problem. Ironically, the 1 ppb
level was a consequence of an EPA crisis in 1983 and it could precipitate another one.
EPA's inability to retreat from the 1 ppb level reveals more than bureaucratic inertia,
however. Over the past decade a climate of bureaucratic loyalty has emerged. It intimidates
lower level Superfund site managers and prevents them from departing from the "company line"
by using lower dioxin levels for cleanup and relocation decisions. This is difficult because as
front-line managers they get the demands from angry people for more effective dioxin testing and
cleanups and for relocation of residents. Defending EPA's 1 ppb is increasingly difficult.
12
Public perceptions
Policy aside, use of I ppb, rather than 2 or 4 ppt based on EPA risk methods, can only be
logically interpreted as either EPA rejecting its own risk assessment methods and results, or EPA
acting as if a dioxin cancer risk greater than I 0·4 is acceptable, which violates the law. When
cleanup levels for other contaminants are set on the basis of 10-6 risk, either by means of risk
assessment or use ofEPA's soil screening levels, use of I ppb is even more untenable. How can
EPA defend using its risk numbers for all chemicals except the more toxic dioxins?
Use of I ppb erodes public confidence in risk assessment, as revealed by advice given to
community groups addressing dioxin cleanup sites: "It doesn't matter if the risk level is one-in-a-
million, one in-one-hundred thousand, or one-ten thousand. [N]o amount of additional exposure
is acceptable and a risk assessment approach that attempts to define a negligible or acceptable risk
is irrelevant. "24
The public, now well informed (some would say in.flamed) about dioxin also knows that
noncancer health effects are now probably more significant than cancer, particularly if synergistic
interactions with pesticides and PCBs occur. For noncancer effects, ATSDR staff have shown
that dioxin levels much lower than 1 ppb are appropriate. All the available scientific information
support using low ppt dioxin TEQ for cleanup and relocation decisions. The scientific community
has sent a clear message that there is no safe level of dioxin exposure. The ubiquitous presence of
dioxins should cause cleanup decisions to recognize other exposures, not to dismiss levels of
dioxin below I ppb because "dioxin is everywhere." EPA' s use of I ppb literally adds insult to
lllJUry.
Conclusion
This risk, historical, and policy analysis provides support for new EPA Superfuud
guidance that specifies the 2 and 4 ppt levels for residential and cleanup site soils, but permits use
of different dioxin TEQ levels if they are supported by site specific information. The guidance
should clarify that chronic health effects other than cancer should be considered, that past and
other sources of dioxin and PCB exposures should be accounted for, that control samples should
be used to determine background levels, that EPA method 8290 should be routinely used, and
that non-detects should be converted to onehalftheir actual method detection limits to calculate
TEQs. The guidance should also clarify what types of sites should be tested for dioxins in soils,
because cases have arisen where either no dioxin testing was performed or where the testing was
performed very late in the Superfuud process, even though site information suppo1ted dioxin
testing. EPA could also provide a framework for evaluating past decisions and whether there are
grounds for reexamining them.
13
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