composting of explosives and propellant contaminated soils under

8/8/2019 Composting of Explosives and Propellant Contaminated Soils Under

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Jou rnal o f Indu strial Microbiology, 9 (1992) 137-144Elsevier 13 7SIM 00400C o m p o s t i n g of exp los ives and prope l lant contaminated so i l s underthermophi l i c and mesophi l i c cond i t ions

R i c h a r d T . W i l li a m s a, p . S c o t t Z i e g e n f u s s 1 a n d W a y n e E . Sisk 2t Roy F. Weston, Inc., West Chester, Pennsylvania and 2 U.S. Army Toxic and Hazardous Materials Agency, Aberdeen Proving Ground,

Maryland, U.S.A.(Received 23 Janu ary 1991; accep ted 26 No vem ber 1991)

Key words: Com post ing; Explosives; Prop el lants ; Thermo phi l ic; Mesophil ic; Biorem ediat ion

S U M M A R YComposting was investigated as a bioremediation technology for clean-up of sediments c ontaminated with explosives and propellants. Two field

demon strations we re co nducted, the first us ing 2,4,6-trinitrotoluene (TNT), octahydro-l,3,5,7-tetranitro-l,3,5,7-tetraazocine (HM X), hexahydro-1,3,5-trinitro-l,3,5-triazine (RD X), and N-me thyl-N,2,4,6-tetranitroaniline (tetryl) contam inated sedime nt, and the seco nd using nitrocellulose (NC )contaminated soil. Tests w ere conducted n thermophilic and m esophilic aerated static piles. Extractable TNT was reduced from 11840 mg/kg o 3 mg/kg,and NC from 13 090 mg/kg to 16 mg/kg under thermophilic conditions. Unde r m esophilic conditions, TNT was reduced from 11 190 mg/kg o 50 mg/kg.The thermophilic and me sophilic half-lives we re 11.9 and 21.9 clays or TN T, 17.3 and 30.1 day s for RD X, and 22.8 and 42.0 days for H M X, respectively.Known nitroaromatic ransformation products ncreased n concentrationover he first several weeks of he test period, but decreased o low concentrationsthereafter.

I N T R O D U C T I O NT h e m a n u f a c t u r e a n d h a n d l i n g o f e x p lo s iv e s a n d p r o -

p e l l a n t s h a s r e s u l t e d i n s o i l a n d s e d i m e n t c o n t a m i n a t i o na t U . S . A r m y m u n i t i o n s f a c il it ie s . T h e U n i t e d S t a t e sA r m y is in v e s t i g a ti n g b i o r e m e d i a t i o n u s i n g c o m p o s t i n g a sa c a n d i d a t e t e c h n o l o g y fo r d e c o n t a m i n a t i n g t h e s e c o n -t a m i n a t e d s o il s. I n a d d i t i o n , c o m p o s t i n g i s b e in g i n v e st i-g a t e d a s a d i s p o s a l t e c h n o l o g y fo r t h e s i g n i f i c a n t q u a n t i -t ie s o f n o n - s p e c i f i c a t i o n g r a d e n i t ro c e l l u lo s e ( N C ) t h a th a v e a c c u m u l a t e d a t p r o d u c t i o n f a c i l i t i e s .

C o m p o s t i n g i s a b i o l o g i c a l p r o c e s s i n w h i c h o r g a n i cm a t e r i a l s a r e b i o d e g r a d e d b y m i c r o o r g a n i s m s , r e s u l ti n gi n t h e p r o d u c t i o n o f o r g a n i c a n d i n o r g a n i c b y - p r o d u c t sa n d h e a t . T h is h e a t e n e r g y is t r a p p e d w i t h in t h e c o m p o s t -i n g m a t r i x , l e a d i n g t o t h e s e l f - h e a t i n g t h a t i s a c h a r a c -t e r is t ic o f c o m p o s t i n g . F o r b i o r e m e d i a t i o n p u r p o s e s , e l e-v a t e d t e m p e r a t u r e c o m p o s t i n g r e q u i re s m i x i n g r e a d i lyb i o d e g r a d a b l e o r g a n i c m a t t e r ( s u c h a s a g r ic u l t u ra lw a s t e s ) w i t h t h e c o n t a m i n a t e d m a t r i x . B u l k i n g a g e n t ss u c h a s w o o d c h i p s m a y a l s o b e r e q u ir e d t o e n h a n c e t h ep o r o s i ty a n d a e r a t io n o f t h e m i x tu r e t o b e c o m p o s t e d .

T h e m i x t u r e t o b e c o m p o s t e d i s t y p i c a l l y s h a p e d i n t oa p i l e o r p l a c e d i n a v e s s e l t o f a c i l i t a t e h e a t r e t e n t i o n a n dp r o c e s s c o n t r o l . C o m p o s t i n g is i m p l e m e n t e d a t o n e o f

Correspondence: R.T. Wil l iams, Roy F. Weston, Inc. , OneWeston Way, West Chester , Pennsylvania 19380, U.S.A.

t h r e e g e n e r a l l e ve l s & t e c h n o l o g y ; w i n d r o w , a e r a t e d s t a t i cp il e , a n d m e c h a n i c a l i n -v e s s el . P i le s ( o r w i n d o w s ) o f th em i x t u re t o b e c o m p o s t e d m a y b e c o n s t ru c t e d . U n m a n i p u -l a t e d p il e s, h o w e v e r , a r e s u b j e c t t o p o o r p r o c e s s c o n t r o l .T u r n i n g ( m i x i n g ) o f t h e p i l e s i n c r e a s e s t h e a b i l i t y t o c o n -t r o l t e m p e r a t u r e , o x y g e n , a n d m o i s t u r e . A e r a t e d s t a t i cp i le s h a v e a n e t w o r k o f p i p e u n d e r n e a t h t h e m i x t u re t o b ec o m p o s t e d t o f a c il it a te t e m p e r a t u r e a n d o x y g e n c o n t r o lb y v e n ti l a ti v e m e a n s . M e c h a n i c a l i n - v e s s e l sy s t e m s p r o -v i d e t h e g r e a t e s t p r o c e s s c o n t r o l , b u t r e q u i r e c o s t l y fa c i li -t i e s . A l t h o u g h c o m p o s t i n g i s t y p i c a l l y a n a e r o b ~ 6 p r o c e s s ,a n a e r o b i c m i c r o e n v i r o n m e n t s l ik e ly f o r m w i t h i n th e c e n -t r a l r e g io n s o f p a r t i c le s i n a c o m p o s t i n g m i x t u re .

C o m p o s t i n g i s w i d e l y u s e d t o t r e a t w a s t e w a t e rs l u d g e s , p r o c e s s i n g w a s t e s , a n d m u n i c i p a l r e f u s e . T h ea d v a n t a g e s o f c o m p o s t i n g as a b i o r e m e d i a ti o n m e t h o dh a v e b e e n d i s c u s s e d p r e v i o u s l y [ 1 ]. T h e y i n c l u d e : 1 ) e le -v a t e d t e m p e r a t u r e s t h a t f a c i l i t a t e a h i g h e r c o n t a m i n a n td e g r a d a t i o n r a t e ; 2 ) e n h a n c e d o p p o r t u n i t i e s f o r c o m e t a -b o l i s m ; 3 ) c h a n g i n g p h y s i c a l / c h e m i c a l m i c r o e n v i r o n -m e n t s w i t h i n a c o m p o s t i n g m a s s t h a t r e s u l t in a d iv e r s i tyo f m i c r o b i a l c o m m u n i t i e s a n d m e t a b o l i c a c t i v it y ; a n d4 ) g r e a t e r c o n t a m i n a n t a v a i la b i li ty d u e t o h i g h e r c o n t a m i -n a n t s o l u b i l i t y a n d m a s s t r a n s f e r a t e l e v a t e d t e m p e r a -t u res .

C o m p o s t i n g o f e x p l o s iv e s a n d p r o p e l l a n t s , e s p e c i a l ly2 , 4 , 6 - t r i n i t r o t o l u e n e ( T N T ) , h a s b e e n i n v e s t i g a t e d b ys e v e r a l r e s e a r c h e r s . O s m o n a n d A n r [2 ] a n d

0169-4146/92/$03.50 9 1992 Society for Indust r ial Microbiology


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138K l a u s m e i e r e t a l. [ 3] b o t h o b s e r v e d b i o t r a n s f o r m a t i o n o fT N T i n l a b o r a t o r y - s c a l e c o m p o s t s y s t e m s . K a p l a n a n dK a p l an [4 ] s t u d i ed t h e d eg r ad a t i o n o f 1 4C - T N T i n a l ab o -r a t o r y - s ca l e s y s t em , b u t d i d n o t d e t ec t t h e r e l ea s e o f1 4C O 2. T h ey d i d , h o w ev e r , o b s e r v e t h e f o r m a t i o n o fr ed u c t i o n p r o d u c t s an d t h e b i n d i n g o f 14C t o t h e o r g an i cm a t t e r f r a c ti o n . T h e p e r c e n t a g e o f 14C t h a t w a s b o u n d t ot h e o r g a n i c m a t t e r i n c o m p o s t i n c re a s e d w i t h i n c re a s i n gco m p o s t ag e an d s t ab i l i t y .

I s b i s t e r e t a l . [ 5 ] ev a l u a t ed t h e d eg r ad a t i o n o f1 4 C - T N T a n d 1 4 C - h ex ah y d r o - 1 ,3 ,5 - t ri n i t ro - l , 3 ,5 - t r ia z i n e( R D X ) i n l a b o r a t o r y - s c a l e c o m p o s t s y s t e m s , a s w e l l a st h e d e g r a d a ti o n o f u n la b e ll e d T N T a n d R D X i ng r e e n h o u s e - s c a l e s y s t e m s . B o t h s t u d i e s d e m o n s t r a t e dt h a t R D X a n d T N T c o n c e n t r a t i o n s r a p i d l y d e c l i n e d d u r -i ng s ix w e e k s o f c o m p o s t in g , a 4 C - R D X w a s c o n v e r t e d t o14CO2, b u t n o e v i d e n c e o f 1 4 C O 2 p r o d u c t i o n f r o m1 4 C - T N T w a s o b s e r v e d . C o n t r a r y t o K a p l a n a n d K a p l a n[ 4] , I s b i s t e r e t a l. [ 5 ] f o u n d o n l y m i n o r am o u n t s o f T N Tr ed u c t i o n p r o d u c t s . A f t e r ad d i t i o n a l w o r k , I s b i s t e r e t a l.[5 ] co n c l u d e d t h a t t h e r e a s o n f o r th i s d i s c r ep an cy w ase i t h e r t h a t K a p l a n a n d K a p l a n d i d n o t a c h i e v e c o m p o s t -i n g i n t h e i r l ab o r a t o r y - s ca l e s y s t em an d / o r t h a t t h eyf o r m e d t h e r e d u c t i o n p r o d u c t s d u r i n g th e i r d r y i n g o re x t r a c t io n p r o c e d u r e s .

D o y l e e t al . [6 ] co n d u c t e d l ab o r a t o r y - (1 4 C ) an d p i l o t-s c a l e ( u n l a b e l l e d ) s t u d i e s w i t h T N T , R D X , o c t a h y d r o -1 , 3 , 5 , 7 - t e t r a n i t r o - l , 3 , 5 , 7 - t e t r a a z o c i n e ( H M X ) , a n d N -m e t h y l - N ,2 ,4 ,6 - t e t r an i t r o an i l i n e ( t e t r y l ) , an d N C . I n t h el ab o r a t o r y s t u d y , 14C f r o m 1 4 C - T N T w as r eco v e r ed p r i -m a r i l y i n t h e u n e x t r a c t e d r e s id u e . E x t r a c t a b l e T N T a l s ow a s r ed u c ed t o l o w l ev e l s i n t h e p i l o t - s ca l e s tu d i e s . R D X ,H M X , t e tr y l, a n d N C w e r e m i n e r a l i z e d t o v a r y in g e x te n t s .R e c e n t l a b o r a t o r y s tu d i e s [7 , 8 ] h a v e d e m o n s t r a t e d t h a tT N T c a n b e e x t e n s i ve l y m i n e r a l i z e d a n d s e r v e a s th e s o l es o u r c e o f c a r b o n a n d e n e rg y .

T h e p r i m a r y o b j e c t i v e o f t h e p r e s e n t s t u di e s w a s t oev a l u a t e t h e t ech n i ca l f ea s i b i l it y o f ae r a t ed s t a t i c p i leco m p o s t i n g a s a t e ch n o l o g y f o r r em ed i a t i n g s o i l s an ds e d im e n t s c o n t a m i n a t e d w i th t h e e x p l o si v es T N T , H M X ,R D X , a n d t e t r y l , a n d t h e p r o p e l l a n t N C . T h e e x p l o s i v e sw e r e p r e s e n t a s c o n t a m i n a n t s i n l a g o o n s e d i m e n t s a s ar e s u lt o f t h e d i s p o s a l o f ' p i n k w a t e r ' , w h i c h w a s g e n e r a t e dd u r i n g m u n i t i o n s p a c k i n g a n d l o a d i n g o p e r a t i o n s a t t h eL o u i s ia n a A r m y A m m u n i t i o n P l a n t ( L A A P ) . T h e p r o p e l -l a n t N C w a s p r e s e n t a s a s o il c o n t a m i n a n t a s a r e su l t o fd i s p o s a l o f N C p r o d u c t i o n w a s t e w a t e r a t th e B a d g e rA r m y A m m u n i t i o n P l an t ( B A A P ) , B a r a b o o , W I . N Cw a s t e ( 'f i ne s ') h a d a l s o a c c u m u l a t e d i n l a g o o n s a t B A A P .S e c o n d a r y o b j e c t i v e s i n cl u d e d e v a l u a t i n g t r a n s f o r m a t i o nu n d e r t h e r m o p h i l i c v s . m e s o p h i l i c t e m p e r a t u r e s , t h ec h a n g e i n m i c r o b ia l n u m b e r s , a n d t h e p r o d u c t i o n o f t r a n s -f o r m a t i o n p r o d u c t s w h e n S t a n d a r d A n a l y t i c a l R e f e r e n c eM a t e r i a l s ( S A R M s ) w e r e a v a i l a b l e .

V a l u es f o r r e l ev an t p h y s i ca l an d ch e m i ca l p r o p e r t i e s o fT N T [ 9 ], H M X [ 10 ], an d R D X [ 11 ], r e s p ec t i v e l y a r e :w ate r so lub i l i ty a t 20 ~ 0 .013 g /100 g , 6 .63 mg/1, and42 .3 mg/ l ; mel t ing po in t , 80 .1 to 81 .6 ~ 276 to 280 ~an d 2 0 4 .1 ~ v ap o r p r e s s u r e , 0 .05 3 m m H g a t 8 5 ~3 x 1 0 - 9 m m H g a t 10 0 ~ ( d a t a n o t av a i l a b le f o r R D X ) .I n f o r m a t i o n o n s o r p t i o n co e f f i c ien t s an d H e n r y ' s lawd e t e r m i n a t i o n s co u l d n o t b e l o ca t ed . A l l t h r ee ex p l o s i v esan d N C a r e g en e r a l l y co n s i d e r ed t o b e n o n v o l a t i l e .M A T E R IA L S A N D M E T H O D S

C o n c r e t e t e s t p a d s w e r e c o n s t r u c t e d a t b o t h B A A Pa n d L A A P w i t h d r a i n a g e c h a n n e l s t h a t c o n n e c t e d t o as u m p l o c a t e d b e l o w g r a de . W a t e r f r o m t h e s u m p w a s

T A B L E 1Materials balance o f mixture to be compostedMaterial Volume Mass Percent(m 3) (kg)

V o l u m e M as sLAAP piles 1 and 2Sedim ent 0.8 1040 3 24Alfalfa 10.0 430 38 10Straw /Ma nure 12.4 1120 47 25H ors e feed 3.4 1810 12 41

To tal 26 .6 4400 100 100BAAP piles 1 and 2So il 1.9 1836 9 19A lfalfa 10.5 1072 49 11M anure 4.6 4318 21 45H orse feed 2.3 1550 ll 17W ood chips 2.1 727 10 8

Total 21 .4 9503 100 100BAAP pile 3So il 1.2 1155 12 22Alfalfa 4.0 410 41 8M anure 2.8 2630 29 51H ors e feed 1.2 805 13 16W ood chips 0.5 171 5 3

To tal 9.7 5171 100 100BAAP pile 4Soil 2.0 1925 19 33Alfalfa 3.1 317 30 5M anu re 2.9 2724 28 44H ors e feed 1.2 805 12 13W ood chip s 1.1 376 11 5

To tal 10.3 6147 100 100


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r e - a p p l i e d t o t h e c o m p o s t p i l e s w h e n m o i s t u r e w a sr e q u ir e d . T h e p a d s w e r e i n d i v id u a l ly c o v e r e d b y a n o p e n -s i d ed s t r u c t u r e .

T h e m i x t u r e to b e c o m p o s t e d a t L A A P ( T a b le 1) w a sp r e p a r e d u s i n g h o r se m a n u r e a n d s o i l e d b e d d i n g ( s t ra w ) ,a l f a lf a , h o r s e f eed ( P u r i n a B a l an c ed B l en d 1 4 ), an d co n -t a m i n a t e d s e d i m e n t . S l u r r ie d c o w m a n u r e w a s u s e d inp l a c e o f h o r s e m a n u r e a t B A A P ( T a b l e 1 ). T h e L A A Ps e d i m e n t c o n t a i n e d T N T ( 56 8 00 m g / k g ) , R D X ( 17 9 00 r ag /k g ) , H M X ( 23 9 0 m g / k g ) , a n d t e t r y l (6 5 0 m g / k g ) ; B A A Ps o il co n t a i n e d o n l y N C ( 18 8 0 0 m g / k g ) . S aw d u s t , w o o dc h i p s , a n d b a l e d s t r a w w e r e u s e d t o c o n s t r u c t t h e c o m -p o s t p i l e b a s e an d i n s u l a t i n g co v e r . A m ech an i ca l f eeds y s t e m , d e v e l o p e d i ni ti a ll y t o m e t e r e x p l o s i v e s - c o n t a m i -n a t e d s o il i n to a n i n c i n e ra t o r , w a s u s e d t o h o m o g e n i z es e d i m e n t a n d t o m i x t h e m a t e r i a l t o b e c o m p o s t e d a tL A A P . A R e e l A u g g ie ( K n i g h t M a n u f a c t u r i n g C o r p . ) w a su s e d t o m i x t h e m a t e r i a l t o b e c o m p o s t e d a t B A A P .

T w o l a n d fi ll t h e r m o c o u p l e p r o b e s ( A t k i n s T e c h n i c a l )p e r p i l e w e r e u s ed t o co n t i n u o u s l y m o n i t o r i n t e r n a l p i l et e m p e r a t u r e s a t L A A P . O n e p r o b e w a s p l a c e d 6 0 c mi n s i d e t h e p i le , 9 0 cm ab o v e p a d l ev e l , an d 6 0 cm f r o m t h eb l o w e r e n d o f t h e p i le . T h e o t h e r p r o b e w a s i n s e r te d i n t ot h e cen t e r o f t h e p i l e ad j ac en t t o t h e t h e r m i s t o r co n t r o l l i n gt h e o p e r a t i o n o f t h e b l o w er . A l an d f il l p r o b e eq u i p p edw i t h a h a n d - h e l d d i g it a l t h e r m o m e t e r w a s u s e d t o m a n u -a ll y m o n i t o r t e m p e r a t u r e s o n a d a i l y b a s is . A t B A A P , s ixt h e r m o c o u p l e s p e r p i l e w e r e u s e d .

T h e m i x t u r e t o b e c o m p o s t e d w a s p l a c e d o n a b a s et h a t c o n t a i n e d a s y s t e m o f p e r f o r a t e d A D S p o l y e th y l e n ed r a i n a g e t u b i n g ( 1 0 - c m d i a m e t e r ) p l a c e d w i t h i n a w o o dc h i p b a s e a n d c o n n e c t e d ( n o n p e r f o r a t e d t u b i n g ) t o a ne x p l o s i o n - p r o o f r a d i a l -b l a d e b l o w e r . T h e b l o w e r w a s u s e dt o p u l l a i r t h r o u g h t h e co m p o s t p i l e . B l o w er cy c l i n g an dp i le t e m p e r a t u r e w e r e c o n t r o ll e d b y b o t h t i m e r ( s t a r t - u pp e r i o d ) a n d t e m p e r a t u r e f e e d b a c k s y s t e m s . T h e t e m p e r a -t u r e f e e d b a c k s y s t e m c o n s i s t e d o f s oi l t h e r m i s t o r s t h a tm e a s u r e d c o m p o s t t e m p e r a t u r e a n d p a n e l -m o u n t e dF e n w a l s e ri e s 55 1 th e r m i s t o r - s e n s i n g te m p e r a t u r e c o n -t ro l l er s . T h e m e s o p h i l i c se t p o i n t ( L A A P a n d B A A P p i le1 ) w as 3 5 ~ an d t h e t h e r m o p h i l i c s e t p o i n t ( L A A P p i l e2 , B A A P p i l e s 2 , 3, an d 4 ) w as 5 5 ~

T h e m i x t u r e s t o b e c o m p o s t e d w e r e p r e p a r e d a s f o l -l o w s. S e d i m e n t o r s o il w a s h o m o g e n i z e d a n d a n a l y z e d f o rex p l o s i v es o r p r o p e l l an t co n cen t r a t i o n s . S o i l , am en d -m e n t s , a n d 8 k g o f f e r ti l iz e r ( n i t r o g en , p o t a s s i u m , p h o s -p h o r u s , 1 3 : 1 3 : 1 3) f o r each p i l e w e r e t h en b l en d ed . T h em a t e r i a l b a l a n c e o f t h e m i x t u r e s i s p r e s e n t e d i n T a b l e 1.M i x t u r e s w e r e d e v e l o p e d b a s e d o n C : N r a t i o , w i t h a g o a lo f 3 0 : 1 , a n d t h e p r e s e n c e o f a b u n d a n t d e g r a d a b l eb i o m as s . S o i l w as ad d ed a t a l ev e l s u f f i c i en t t o r e s u l t i ns ig n i fi c an t d e t e c t a b l e c o n t a m i n a t i o n . E a c h l o a d o f c o m -p o s t a t L A A P w a s m o i s t e n e d w i t h w a t e r a s i t w a sd e l i v e r ed t o t h e p i l e b a s e . A p p r o x i m a t e l y 1 5 0 0 l i te r s o f

13 9w a t e r w e r e a p p l i e d p e r p il e. N o a d d i t io n a l m o i s t u r e w a sr e q u i r e d a t t h e s t a r t o f t h e B A A P t e s t s .

N C p r o d u c t i o n w a s t e f r o m a s t o r a g e b a s i n a t B A A Pw a s b l e n d e d w i t h t h e p i l e 4 m i x t u r e t o b e c o m p o s t e d t of o r m n o m i n a l co n cen t r a t i o n s o f 5 , 1 5 , 3 0 , 6 0, an d 8 0 ~o b yw e i g h t . F o u r s e t s o f t r i p l ica t e s am p l e s f o r each c o n cen -t r a t i o n w e r e p r e p a r e d . T h r e e s e t s w e r e i n d iv i d u al ly p l a c e di n n y lo n b a g s t h a t w e r e t h e n p l a c e d i n p o ly e t h y l e ne m e s hs l eev es . T h e t h r ee b ag g ed s e t s w e r e p l aced i n t h e m i d d l eo f p i l e 4 an d r e m o v e d a t d e s i g n a t ed t i m es f o r an a ly s i s . T h ef o u r t h s e t w a s a n a l y z e d a s a t i m e z e r o s a m p l e .

P i l e c o n s t r u c t i o n a t L A A P w a s c o m p l e t e d a n d t h et e m p e r a t u r e c o n t r o l s y s t e m a n d re c o r d e r w e r e s t a r t e d o n2 5 F e b r u a r y 1 9 8 8 . S a m p l e s w e r e t a k e n w i t h a 3 - in c hd i am e t e r s o i l au g e r f r o m t h e ce n t r a l r eg i o n o f t h e p i l e f r o ma t l e a s t t h r ee l o ca t i o n s a l o n g t h e l en g t h o f t h e p i l e fo r eachs a m p l i n g t im e . T h e i n s ul a t in g c o v e r w a s r e m o v e d p r i o r t ot a k i n g s a m p l e s . S a m p l e s w e r e m i x e d b y h a n d p r i o r t os u b s a m p l i n g f o r e x t r a c ti o n a n d a n a ly s i s. S a m p l e s ( a t l e a s tt h r e e p e r s a m p l i n g t i m e ) w e r e a n a l y z e d f o r c o n t a m i n a n tco n c en t r a t i o n n i n e t i m es o v e r a 1 5 3 - d ay t e s t p e r i o d .

M o i s t u r e w a s a d d e d w h e n t e m p e r a t u r e s s t a r t e d t o fa ll.T h i s g en e r a l l y o ccu r r ed w h en p e r cen t m o i s t u r e f e l l b e l o wa p p r o x i m a t e l y 4 0~ o. T h e L A A P c o m p o s t p i le s w e r e in d i-v i d u a ll y d is m a n t l e d a n d t h e c o m p o s t i n g m i x t u r e r e m i x e dan d r em o i s t en ed o n d ay s 3 3 , 60 , an d 1 1 1 . P i le s 1 an d 2 a tB A A P w e r e m o n i t o r ed f o r 1 51 d ay s s t a r t in g o n 2 9 A p r i l1 9 88 . P i l e s 3 an d 4 w er e m o n i t o r ed f o r 1 12 d ay s s t a r t i n go n 2 8 S e p t e m b e r 1 9 88 . T h e B A A P p i le s w e r e i n d iv i d u al l yd i s m a n t l e d a n d t h e c o m p o s t i n g m i x t u r e re m i x e d a n dr em o i s t en ed a t w eek 6 ( p i le s 1 an d 2 ) o r w e ek 7 ( p il e s 3an d 4 ) .

A n a l y s e s f o r m e t a l s w e r e c o n d u c t e d b y p r o c e d u r e sd e s c r i b e d in S t a n d a r d M e t h o d s f o r C h e m i c a l A n a l y s i s o fW at e r an d W as t e s ( U .S . E P A 6 0 0 / 4 - 7 9 - 0 2 0 , 1 9 7 9 ) . C o m -p o s t s a m p l e s w e r e a n a l y z ed f o r T N T , R D X , H M X , t e tr y l,a n d t r a n s f o r m a t i o n p r o d u c t s b y U . S . A r m y T o x i c a n dH a z a r d o u s M a t er ia l s A g en c y ( U S A T H A M A ) M e t h o dL W 0 2 , m o d i f i e d fo r t he e x t r a c t i o n a n d a n a l y si s o f c o m -p o s t . T h e h i g h a b s o r p t i v e c a p a c i t y o f c o m p o s t r e q u i r e d ah i g h e r v o l u m e o f s o l v en t ( 40 m l p e r 1 0 g ) t h an s p ec i f ied i nM e t h o d L W 0 2 . E x p l o s i v e s a n d t r a n s f o r m a t i o n p r o d u c t sw e r e e x t r a c t e d u s i n g a ce t o n it r il e a n d a n a l y z e d b y H P L C .N C w a s a n a l y z e d s p e c t r o p h o t o m e t r i c a l l y u s i n g U S A -T H A M A M e t h o d L Y 0 2 . N C w a s e x t r a c te d w it h a c e t o n eu s i n g u l t r a s o n i c ag i t a t i o n . T h e ex t r ac t w as d r i ed , w as h edi n m e t h a n o l / w a t e r , d i s s o lv e d i n a c e t o n e , a n d h y d r o l y z e dw i t h p o t a s s i u m h y d r o x i d e . N i t r a t e w a s t h e n a n a l y z e d . Am e t h o d b l a n k a n d s t a n d a r d s p i k e s fo r e a c h a n a l y t e w e r ea n a l y z e d w i t h e a c h b a t c h o f s a m p l e s . S p i k e r e c o v e r i e sco n s i s t en t l y ex ceed ed 9 0 ~o i n s t an d a r d s o i l s . U S A -T H A M A s t a n d a r d s o il w a s u s e d f o r r e c o v e r i e s s in c e as t a n d a r d c o m p o s t c o u l d n o t b e d e f i n e d .

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ag a r b y s e r ia l l y d i l u ti n g a 1 0 ~o ( w / v ) co m p o s t / p h o s p h a t eb u f fe r m i x tu r e , w h i c h h a d b e e n v i g o r o u sl y s h a k e n f o r2 r a i n. L a r g e p a r t i c l e s w e r e a l l o w ed t o s e t t le p r i o r t o d i lu t -i n g t h e m i x t u re 9 P l a t e s w e r e i n cu b a t ed i n t h e d a r k a t e i t h e r3 5 o r 55 ~ a n d c o l o n ie s w e r e e n u m e r a t e d a t d a y 2 a n dd ay 5 . S am p l es w e r e d r i ed a t 9 5 ~ f o r 2 4 h f o r m o i s t u r ed e t e r m i n a t i o n s .R E S U L T SLAAP data

T h e p e r c e n t a g e o f m o i s t u re o f L A A P c o m p o s t s a m p l e sd u r i n g t h e t e s t p e r i o d v a r i ed f r o m 2 5 t o 5 6 w e i g h t p e r cen t .A t t e s t i n i t i a ti o n an d f o l l o w i n g r em o i s t en i n g , m o i s t u r ec o n t e n t w a s a p p r o x i m a t e l y 5 0 w e i g h t p e r c e n t . M o i s t u r ec o n t e n t d r o p p e d t o t h e 2 5 - 3 5 ~ o r a n g e o v e r a p e r io d o f 3 0t o 4 0 d a y s . M o i s t u r e d a t a f o r L A A P p i le 1 a r e s h o w n i nF ig . 1. A v e r a g e t e m p e r a t u r e s w i t h in L A A P p i l e s 1 a n d 2a r e p r e s e n t ed i n F i g. 2 . T e m p er a t u r e s d r o p p ed s ig n if i-can t l y w h en t h e p e r cen t m o i s t u r e f e ll b e l o w 3 5 w e i g h tp e r cen t .

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T o t a l ex p l o s i v es i n t h e t h e r m o p h i l i c an d m es o p h i l i cp i le s a t L A A P w e r e r ed u ce d f r o m 1 7 8 7 0 an d 1 6 4 6 0 r ag /k g t o 7 4 an d 3 2 6 m g / k g , r e s p ec t i v e l y d u r i n g t h e 1 5 3 - d ayt es t. T h e c o n c e n t ra t io n o f T N T , H M X , a n d R D X w i th int h e t h e r m o p h i l i c p i l e a t L A A P i s p r e s en t ed i n F i g . 3 . N od a t a a r e p r e s e n t e d f o r t e t ry l s in c e th e c o m p o u n d w a sb e l o w d e t ec t i o n l i m i t s i n a l l co m p o s t s am p l e s ( i n c l u d i n gt i m e 0 ) a n a ly z e d . T h e m e a n a n d s t a n d a r d d e v i a t io n ( e r r o rb a r s f o r F i g . 3 , 4 , an d 6 ) a t e ach t i m e p o i n t r ep r e s en t a tl e a s t th r e e a n d a s m a n y a s n in e s a m p l e s . C a l c u l a t e d h a lf -l i ve s ( d ay s ) w e r e 1 2 f o r T N T , 1 7 f o r R D X , an d 2 3 f o rH M X u n d e r t h e r m o p h i l i c c o n d it i o n s a n d 2 2 f o r T N T , 3 0f o r R D X , a n d 4 2 fo r H M X u n d e r m e s o p h i li c c o n di t io n s .

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o b t a i n ed (2 - ami n o -4 , 6 -d i n i t r o t o l u en e ; 4 - ami n o -2 , 6 -d i n j -t r o t o l u en e ; 2 , 4 -d i ami n o -6 -n i t r o t o l u en e ; an d 2 , 6 -d iami n o -4 -n i t r o to l u en e ) . I n i ti a l co n cen t r a t i o n s o f t r an s fo rm a t i o np ro d u c t s i n t h e s e s amp l es r an g ed f ro m n o n d e t ec t ab l e t o2 5 0 mg / k g . T h es e i n d i v id u a l co n ce n t r a t i o n s i n c r eas edo v e r t h e f i r s t s ev e ra l w eek s o f t h e t e s t p e r i o d t o a h i g h o fap p ro x i m a t e l y 1 5 0 0 mg / k g , an d t h en d ec re as ed t o l o wmg / k g l ev e ls th e r ea f t e r . A t d ay 1 53 , t h e co n cen t r a t i o n o feach t r an s fo rma t i o n p ro d u c t w as l e s s t h an 2 2 mg / k g an di n m a n y c a s e s n o n d e t e c t a b l e . T r a n s f o r m a t i o n p r o d u c td a t a fo r L A A P p i l e 2 a r e p r e s en t ed i n F i g . 4 .

S a m p l e s o f w a t e r f r o m t h e s u m p w e r e a n a l y z e d f o rex p l o s iv es an d t r an s fo rm a t i o n p ro d u c t s o n d ay s 0 , 1 6 , 2 2an d 1 5 3 . T h e an a l y t e s w ere b e l o w d e t ec t i o n l i mit s in a l ls u m p w a t e r s a m p le s . S a m p l e s o f s u m p w a t e r w e r e a n a -l y zed fo r me t a l s a t d ay 1 5 3 . Po t a s s i u m , m ag n es i u m,

141s o d i u m, a l u mi n i u m, i r o n , an d ca l c i u m w ere t h e o n l yme t a l s d e t ec t ed a t co n ce n t r a t i o n s g r ea t e r t h an 1 r ag /1 . N omet a l s w e re d e t ec t ed in ex t r ac t s o f co m p o s t s amp l esob ta ined us ing the E PA Tox ic i ty Ch arac ter i s t i c Leachi r~g~P r o c e d u r e ( T C L P ) .

T h e a p p e a r a n c e o f t h e L A A P c o m p o s t c h a n g e d c on -s i d e r ab l y o v e r t h e 1 5 3 -day te s t p e r i o d . W h e n t h e ma t e r i a l st o b e c o m p o s t ed w ere i n it ia l ly mi x ed , t h e mi x t u re h ad ah i g h ly fi b ro u s ap p ea ran ce , a r o u g h t ex t u r e , an d i t s me l l edco n s p i cu o u s l y o f t h e ma t e r i a l s u s ed t o p r ep a re i t. A f t e ra p p r o x i m a t e l y 1 00 d a y s, t h e c o m p o s t h a d b e c o m e m o ~ eso i l- l ike and l ess f ib rous in app earan ce . A t the e nd o f thet e s t p e r i o d , t h e c o m p o s t h a d b o t h t h e a p p e a r a n c e a n dsmel l o f loam y soi l. Al though non qua n t i t a t ive , v i sualex am i n a t i o n o f b o t h cen t r a l an d p e r i p h e ra l s amp l es i n d i-ca t ed t h a t f u n g a l g ro w t h w as c o n s i d e rab l y h eav i e r in t h emes o p h i l ic t h an i n th e t h e rm o p h i l i c pi le a t L A A P. Fu n g a lg ro w t h p en e t r a t ed i n t o t h e cen t r a l r eg i o n s o f a ll p a r t ic l e sex ami n ed .

T h e p r e s e n c e o f m i c r o o r g a n is m s c a p a b l e o f g ro w i ng a t3 5 an d 5 5 ~ w as ev a l u a t ed . P l a t e co u n t s w e re p e r fo rm edu s i n g ex t r ac t s o f s amp l es f ro m t h e mes o p h i l i c an d t h et h e rmo p h i l i c p il e. T w o s e t s o f p la t e s w e re p r ep a red fo reach ex t r ac t . O n e s e t w as i n cu b a t ed a t 3 5 ~ an d t h es eco n d a t 55 ~ A s s h o w n i n F ig . 5 , t h e ma i n t en an c e o f

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14 2t h e co m p o s t p i le t em p er a t u r e a t 35 ~ l ed t o a s e l ec t iv ei n c r e a s e i n t h e n u m b e r o f m i c r o o r g a n i s m s c a p a b l e o fg r o w t h a t 35 ~ a n d a d e c re a s e i n t h e n u m b e r c a p a b l e o fg r o w t h a t 5 5 ~ C . M a i n t e n a n c e o f t e m p e r a t u r e a t 55 ~ i nt h e t h e r m o p h i l i c p i le r e s u l t ed i n an i n c r ea s e i n t h e n u m b ero f m i c r o o r g a n i s m s c a p a b l e o f g r o w t h a t 5 5 ~ a n d ad e c r e a s e i n t h e p o p u l a t i o n c a p a b l e o f g r o w t h a t 3 5 ~BAAP data

T h e p e r c e n t a g e o f m o i s t u re o f B A A P c o m p o s t s a m p l e sv a r i ed f r o m 2 7 t o 6 5 w e i g h t p e r cen t . T h e m o i s t u r e a t t e s ti n i t i a t i o n an d f o l l o w i n g r em o i s t en i n g w as i n t h e 5 5 - 6 5w e i g h t p e r c e n t r a n g e . M o i s t u r e d r o p p e d t o t h e 3 0 - 4 0w e i g h t p e r c e n t r a n g e a f t e r 2 0 - 3 0 d a y s .

T e m p e r a t u r e i n B A A P p i le s 2, 3, a n d 4 r e a c h e d 5 5 t o6 5 ~ w i t h i n f iv e d ay s o f t e s t i n i t ia t i o n . T h e r m o p h i l i ct e m p e r a t u r e s t h e n w e r e m a i n t a i n e d u n t il a p p r o x i m a t e l yd ay 65 , w h en t em p er a t u r e s b eg an a g r ad u a l d ec l i n e in t ot h e m e s o p h i l i c r a n g e. B A A P p i l e 1 m a i n t a i n e d am e s o p h i l i c t e m p e r a t u r e o f a p p r o x i m a t e l y 35 ~ u n t ila p p r o x i m a t e l y d a y 5 7 . A f te r t h is t i m e , t e m p e r a t u r e sc l i m b e d i nt o t h e t h e r m o p h i l ic r a n g e , a n d w e r e b e t w e e n 6 0a n d 6 5 ~ b e t w e e n d a y 7 5 a n d 9 4. T e m p e r a t u r e s t h e ng r ad u a l l y d ec li n ed t o ap p r o x i m a t e l y 30 ~ a t d ay 1 5 0.T e m p er a t u r e co n t r o l i n p il e 1 b ec am e i n e ff ec t iv e a f te rap p r o x i m a t e l y d ay 5 5 , p r e s u m a b l y r e fl ec t in g th e i n ab i l i t yo f a i r t o f lo w w e l l t h r o u g h t h e co m p ac t i n g m i x t u r e .

N C w as s i g n i f i can t l y d e s t r o y ed i n a l l t e s t s co n d u c t eda t B A A P . I n p i le s 1 a n d 2 , N C w a s r e d u c e d i n s a m p l e st ak en f r o m s ev e r a l l o ca t i o n s i n t h e p i l e f r o m a h i g h o f4 93 3 m g / k g an d 3 03 9 m g / k g t o 1 33 m g / k g an d 5 4 m g / k g ,r e s p ec t i v e l y . C o m p o s t f o r t i f i ed w i t h n o m i n a l co n cen t r a -t i o n s o f 3 , 5 , 7 .5 , an d 1 0 % N C w as p l a ced i n m es h b ag sl o ca t ed i n t h e cen t r a l r eg i o n o f p i l e s 1 an d 2 . A f t e r 9 8 d ay s ,N C w a s r e d u c e d f r o m 2 3 6 0 0 m g / k g t o 6 1 m g / k g i n t h e1 0 % N C b a g g e d c o m p o s t s a m p l e p l a c e d in p il e 2. E x t e n -s i v e N C r e d u c t i o n w a s o b s e r v e d i n a l l o t h e r b a g g e ds am p l es p l aced i n p i l es 1 an d 2 .

T h e s o il f ra c t i o n u s e d i n th e m i x t u r e t o b e c o m p o s t e dw a s i n c r e a s e d f r o m 1 9 % ( b y m a s s ) u s e d i n p i le s 1 a n d 2t o 2 2 an d 3 3 % f o r p i le s 3 an d 4 , r e s p ec t i v e ly . I n ad d i t i o n ,N C w a s a d d e d t o c o m p o s t a t h i g h e r c o n c e n t r a t i o n s( n o m i n a l o f 5 , 3 0, an d 6 0 % ) f o r s am p l e s co n t a i n ed i nm e s h b a g s a n d p l a c e d i n p il e 3. R e s u lt s f r o m a m i n i m u mo f f iv e s am p l e s t ak e n f r o m s ev e r a l l o ca t i o n s i n p i le s 3 an d4 f o r each t i m e p o i n t a r e p r e s e n t ed i n Fi g. 6 . N C c o n cen -t r a t i o n i n c o m p o s t c o n t a i n e d i n m e s h b a g s w a s r e d u c e df r o m 1 4 3 1 0 + 3 0 68 m g / k g t o 1 6 62 + 1 4 0 5 m g / k g ; f r o m114500 + 26 160 m g/kg to 2455 + 1028 mg /kg ; a nd f rom218 600 + 23 570 mg/k g to 68 800 + 12190 m g/kg ove r the1 0 1 - d ay t e s t p e r i o d .

S a m p l e s o f s u m p w a t e r w e r e a n a l y z e d f o r N C a t th een d o f t h e t e s t p e r i o d s f o r p i l es 1 an d 2 an d p i l e s 3 an d

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i ~ i i i i t i i F2 0 4 0 6 0 8 0 I O 0Time (days)Fig. 6. C oncentration of nitrocellulose in BAA P piles 3 and 4(error bars represent standard deviation).

4 . N C w as b e l o w t h e d e t ec t i o n l i m i t f o r a l l s u m p s am p l e s .T h e a p p e a r a n c e o f t h e B A A P c o m p o s t c h a n g e d s im i la rl yt o t he L A A P c o m p o s t o v e r t h e t e st p e ri o d . E n u m e r a t i o no f m i c r o o r g a n i s m s i n a ll f o u r p i le s a t B A A P c o n s i s te n t l yd e m o n s t r a t e d p o p u l a t i o n d e n s i ti e s b e t w e e n 106 a n d10 7 cfu/g.D I S C U S S I O N

C o n c e n t r a ti o n s o f so l v e n t- e x tr a c ta b l e T N T , R D X ,a n d H M X i n L A A P p i l e s a n d N C i n B A A P p i l e s w e r es i g n if i can tl y r ed u c ed d u r i n g t h e f i e ld te s t s . F a t e m e ch a -n i s m s t h a t m a y h a v e b e e n r e s p o n s ib l e f o r c o n t a m i n a n tr ed u c t i o n i n c l u d e s o r p t i o n o f ex p l o s i v es an d t r an s f o r -m a t i o n p r o d u c t s t o t h e c o m p o s t m a t r i x , i n c o r p o r a t i o n o fe x p l o s i v e s a n d t r a n s f o r m a t i o n p r o d u c t s i n t o e n v i r o n -m e n t a l l y s t a b le m o l e c u l e s s u c h a s h u m i c a c i d s , a n d m i n -e r a l i za t i o n o f ex p l o s i v es to ca r b o n d i o x i d e , w a t e r , an do t h e r i n o r g an i c s . V o l a t i l i z a t i o n w as u n l i k e l y s i n ce t h ee x p l o s i v e s a n d t h e i r t r a n s f o r m a t i o n p r o d u c t s a r e n o n -vo la t i l e .

T h e f i e l d d e m o n s t r a t i o n u s i n g e x p l o s i v e s - c o n t a m i -n a t e d s o il a t L A A P d e m o n s t r a t e s t h e s i g n if ic a n t t r a n s f o r-m a t i o n p o t e n t i a l (f o r e x a m p l e , e x t r a c t a b l e T N T r e d u c t io n


7/8

f r o m 11 8 40 m g / k g t o 3 m g / k g ) o f t h e e o m p o s t i n g p r o c es s .C o n s e q u e n t l y , c o m p o s t i n g m a y b e a s u i t a b l e te c h n o l o g yf o r r e m e d i a t i n g e x p l o s i v e s - o r p r o p e l l a n t - c o n t a m i n a t e ds o i l an d s ed i m en t , a s w e l l a s s o l i d m a t r i ce s co n t am i n a t edw i t h o t h e r b i o d e g r a d a b l e c o m p o u n d s . T h e d e g r a d a t i o n o fh i gh c o n c e n t r a t i o n s o f N C e n c l o s e d i n m e s h b a g s i n d i -c a t e s t h a t c o m p o s t i n g m a y p r o v e s u i ta b l e f o r t h e d e s t r u c -t i on o f N C p r o d u c t i o n w a s t e . C a u t i o n s h o u l d b e u s e d i ni n t e r p r e t i n g t h es e m es h b ag s r e s u l t s , h o w ev e r , s i n ce anen t i r e ( : o m p o s t p i le co n t a i n i n g a h i g h N C c o n c en t r a t i o nm a y e x h ib i t m u c h d i f fe r e n t c o m p o s t i n g a n d N C d e g r a d a -t i o n ch a r ac t e r i s t i c s t h an t h e s m a l l q u an t i t i e s s t u d i ed i nb ag s i n t h i s p r o g r am .

T h e u t il it y o f c o m p o s t i n g f o r e x p l o s i v e s - c o n t a m i n a t e dm a t r i ce s i s s t i l l i n d o u b t d u e t o t h e n eed f o r ad d i t i o n a ld a t a o n t h e f i na l t r a n s f o r m a t i o n p r o d u c t s a n d t o x i c i ty o ft h e c o m p o s t r e s id u e . A n i n v e s t i g a t io n o f t h e L A A P c o m -p o s t r e s i d u e [ 1 2 ] h a s r e v e a l e d l o w ( # g / m l ) l e v el s o fl e a c h a b l e T N T , H M X , R D X , a n d t w o m o n o a m i n o d i -n i t r o t o l u e n e s . L e a c h a t e s f r o m t h e m e s o p h i l i c c o m p o s tr e s i d u e w er e s l i g h t l y m o r e t o x i c t h an t h o s e f r o m t h et h e r m o p h i l i c co m p o s t r e s i d u e . T h e b as i s f o r t h i s d i f f e r -en ce i s u n k n o w n .

T h e L A A P p r o g r a m d e m o n s t r a t e d s u p e r i o r c o n t a m i -n an t d e s t r u c t i o n u n d e r t h e r m o p h i l i c co n d i t i o n s . T h i s d i f -f e r en ce co u l d a r i s e f r o m g r ea t e r co n t am i n an t s o l u b i l i t y ,h i g h e r r a t e s o f r eac t i o n , o r t h e n a t u r e o f t h e r m o p h i l i c v s .m e s o p h i l i c m i c r o b i a l c o m m u n i t i e s . B o t h v i s u a l o b s e r v a -t i on o f t h e c o m p o s t a n d e n u m e r a t i o n o f m i c r o o r g a n i s m si n d i ca t e t h a t d i f f e r en ces ex i s t b e t w een t h es e m i c r o b i a lc o m m u n i t i e s .

T h e m i c r o b i a l p o p u l a t i o n s i ze d a t a p r e s e n t e d i n F ig . 5a r e s u g g es t i v e o f t h e s e l ec t i v e e f f ec t t em p er a t u r e h as o nt h e o v e r a l l c h a r a c t e r o f t h e m i c r o b i a l c o m m u n i t y . T h ee f fe c t o f th e s e c o m m u n i t y c h a n g e s o n t h e a c t iv i ty o rf u n c t i o n o f i n d i v i d u a l p o p u l a t i o n s , h o w ev e r , i s u n k n o w n .I t i s l i k e l y t h a t t h e s i g n i f i can t ac t i v i t y o f ae r o b i c m i c r o -o r g a n i s m s w i t h in c o m p o s t r e s u l t s in s o m e l o c a l iz e d a r e a so f o x y g e n d e p le t i o n a n d t h u s i n t h e o c c u r r e n c e o fa n a e r o b i c m i c r o s i te s . I n p a r t i c u l a r , t h is w o u l d b e e x p e c t -ed w i t h i n t h e cen t r a l r eg i o n o f p a r t i c l e s g r ea t e r t h an1 - 2 c m , o r in r e g io n s w h e r e t h e m o i s t u r e c o n t e n t e x c e e d sa p p r o x i m a t e l y 6 0~ o o f t h e w a t e r h o l d in g c a p a c i ty .

T h e h i g h v a r i a t i o n o b s e r v e d i n c o n t a m i n a n t l e v e l sb e t w een i n d i v i d u a l s am p l es f r o m d i f f e r en t s am p l i n gp o i n t s e a r l y i n th e t e s t p e r i o d i s re a s o n a b l e a n d m o s tl ike ly r ef lec t s d i f f er ences in microb ia l ac t iv i ty a t d i f f er en tl o ca t i o n s w i t h i n t h e p i l e s . W i t h i n an y o n e o f t h e s ev e r a ls am p l es co l l ec t ed a t o n e t i m e , v a r i a t i o n w as l o w , a s d em -o n s t r a t e d b y t h e a n a l ys i s o f s e v e r a l s u b s a m p l e s . T h e h i g hv a r i a t i o n o b s e r v e d in N C c o n t e n t w i t h i n t h e B A A P m e s hbag s tud ies r ef lec t s the d i f f icu l ty in ob ta in ing a un i fo rmN C d i s t r i b u t i o n w i t h i n a m i x t u r e t o b e c o m p o s t e d .

14 3A co s t an a l y s i s [ 1 3 ] h as i n d i ca t ed t h a t t h e ab i l it y t o

eco n o m i ca l l y p r o ces s s i g n if i can t q u an t i t i v e s o f s o i l u s i n gc o m p o s t i n g i s s e n si t iv e t o t h e k i n e ti c r a t e o f c o n t a m i n a n td es t r u c t i o n an d , t o a g r ea t e r ex t en t , s o i l co n cen t r a t i o n i nt h e m i x t u r e t o b e c o m p o s t e d . T h e B A A P s t u d y d e m o n -s t r a t ed t h a t s o il l o ad i n g s a s h i g h a s 3 3 ~o b y m a s s co u l db e i n co r p o r a t ed w i t h o u t d i m i n i s h i n g t h e ab i l i t y t o g en -e r a t e h e a t a n d m a i n t a i n t h e r m o p h i l i c t e m p e r a t u r e s d u r -i n g w i n t e r i n Wi s co n s i n . Fo r B A A P p i l e s 3 an d 4 , m o r et h a n h a l f o f t h e d a i l y lo w t e m p e r a t u r e s w e r e b e l o w 0 ~C ,w i th a m a x i m u m lo w t e m p e r a t u r e o f - 2 0 ~ F o r m a n yd a y s , t h e d a i l y h i g h t e m p e r a t u r e w a s a l so b e l o w 0 ~C . I fe f fe c ti v e c o m p o s t i n g a n d c o n t a m i n a n t d e s t r u c t io n c a n b each i ev e d w i t h a s o il v o l u m e o f 2 0 ~o a n d a t o t a l am en d -m e n t c o s t o f $ 5 0 / to n , c o m p o s t i n g c a n c o m p e t e w i t hi n c i n e r a t i o n a s a co s t - e f f ec t i v e r em ed i a l a l t e r n a t i v e .

W h i l e c o m p o s t i n g i s a f e a s i b l e b i o r e m e d i a t i o na p p r o a c h , c e r t a i n c a u t i o n s m u s t b e k e p t i n m i nd . V o l a t il ec o n t a m i n a n t s m a y b e r e le a s e d d u r i n g c o m p o s t i n g r e q u ir -i n g a d d i t i o n a l t r e a t m e n t e q u i p m e n t a n d s u b s e q u e n ti n c r eas e d co s t s . M i c r o o r g an i s m s h av e y e t t o b e e ff ec t iv e l yu t i li z e d f o r t h e t r e a t m e n t o f m o s t h e a v y m e t a l s . C o n -s eq u en t l y , a ca r e f u l ev a l u a t i o n i s r eq u i r ed w h en h aza r d -o u s co n c en t r a t i o n s o f m e t a l s o r v o l a t il e o r g an i cc o m p o u n d s a r e p re s e n t . A l t h o u g h c o m p o s t i n g is a w a t e r -c o n s u m i n g p r o c e s s , t h e p o t e n t i a l f o r l e a c h a t e f o r m a t i o ns h o u l d b e co n s i d e r ed . F i n a l l y , i t i s c r u c i a l t o u n d e r s t an dt h e f i n a l f a t e an d t o x i c i t y o f t h e co n t am i n an t s p r i o r t oi m p l e m e n t i n g c o m p o s t i n g f o r h a z a r d o u s s u b s t a n c e d e -s t r u c t i o n . T r ea t ab i l i t y s t u d i e s s h o u l d b e co n d u c t ed t oe n s u r e t h a t a c c e p t a b l e d e c o n t a m i n a t i o n c a n b e a c h i e v ed .A C K N O W L E D G E M E N T S

T h e a u t h o r s t h an k W. Sn i ff en , W. L o w e , L. M o r s e , E .S c h a e f e r , a n d E . M c G o v e r n f o r t e c h n i c a l s u p p o r t . T h i sw o r k w a s s p o n s o r e d b y t h e U . S . A r m y ( c o n t r a c t p u r c h a s eo r d e r N o . D A A K 1 1 -8 5 - D -0 0 0 7 ). T h i s p u b l i ca t i o n r e f l ec t st h e p e r s o n a l v i e w s o f t h e a u t h o r s a n d d o e s n o t s u g g e s t o rr e f l ec t t h e p o l i cy , p r ac t i ce s , o r d o c t r i n e o f t h e U .S . A r m yo r g o v e r n m e n t o f t h e U n i t e d S t a t e s.R E F E R E N C E S

1 W illiams, R.T . and C.A. Myler. 1990. Bioremediation usingcomposting. Biocycle. No vem ber, 1990.20 sm an , J i . and C.C. Andrews . 1978 . The b iodegradation o fTN T in enhanced soil and c omp ost systems. In: U.S. ArmyArm ame nt Research and Development Com man d Rep or tARLD-TR-77032: Do ver , New Jersey, U .S.A.3 Klausmeier, R .E., E.I . Jam ison and A . Tatyrek. 1982. Corn-posting of TN T: Airborne Products and Toxicity. In: U.S.Armament Research and Development Command Repor tAD-E400-744: Dover , N ew Jersey, U.S.A.


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14 44 K a p l a n , D . L . a n d A . M . K a p l a n . 1 9 8 2 . T h e r m o p h i l ic

b io t r a n s fo rm a t io n s o f 2 ,4 ,6 - tr i n i t ro to lu e n e u n d e r s im u la t e dc o m p o s t in g c o n d i t i o n s . Ap p l . En v i ro n . Mic ro b io l . 4 4 :7 4 7 -7 6 0 .

5 I sb i s t e r , J .D . , G .L . An sp a c h , J .F . Ki t c h e n s a n d R .C . Do y le .1 9 8 4 . Co m p o s t in g fo r d e c o n ta m in a t io n o f so i l s c o n t a in in ge x p lo s iv e s. M ic ro b io lo g ie s . 7 : 4 7 -7 3 .6 Do y le , R .C ., J .D . I sb i s t e r , G .L . An sp a c h a n d J .F . Ki t c h e n s .1 98 6. Co m p o s t in g o f e x p lo s iv e s /o rg a n i c s c o n t a m in a t e d so i l s.I n : U . S . A r m y R e p o r t A M X T H - T E - C R - 8 6 0 7 7 : A b e r d e e nP r o v i ng G r o u n d , M a r y l a n d , U . S . A .

7 Tu d o r , F . , J .A . Bu m p u s a n d S .D. Au s t . 1 9 90 . B io d e g ra d a t io no f TNT (2 ,4 ,6 - t r i n i t ro to lu e n e ) b y Phanerochaete chryso-sporium. Appl . Environ . Microbio l . 56 : 1666-1671.

8 Un k e fe r , P . J . , M.A . Alv a re z , J .L . H a n n e r s , C . J. Un k e fe r , M.S te n g e r a n d E .A. M a rg io t t a . 1 9 90 . B io re m e d ia t i o n o f Ex p lo -s iv e s. P re se n t e d a t t h e W o rk sh o p o n Al t e rn a t i v e s t o Op e nB u r n i n g /O p e n D e t o n a t i o n o f P r o p e l le n t s a n d E x p l o s iv e s ,T y n d a l l A i r F o r c e B as e , P a n a m a C i ty , F l o r i d a , U . S . A , 2 7 - 2 8M a r c h 1990.

9 G o r d o n , L . a n d W . R . H a r t l ey . 1 9 8 9 . H e a l t h A d v i s o r y o n2 ,4 ,6 -Tr in i t ro to lu e n e . Pu b l i sh e d b y U.S . EPA Of f i c e o fDr in k in g Wa te r , Wa sh in g to n , D.C . 2 0 4 60 , U.S .A.

1 0 Mc Le l l a n , W.L . , W.R. Ha r t l e y a n d M.E . Bro we r . 1 9 8 8 .He a l th Ad v i so ry fo r He x a h y d ro - 1 ,3 ,5 - t ri n o t ro - 1 ,3 ,5 -t r ia z in e( R D X ) . P u b l i s h e d b y U . S . E P A O f fi ce o f D r i n k i n g W a t e r ,Wa sh in g to n , D.C . 2 0 4 6 0 , U.S .A.11 M c Le l l a n , W.L . , W.R. H a r t l e y a n d M.E . Bro we r . 1 9 88 .He a l th A d v i so ry fo r Oc ta h y d ro - l ,3 ,5 ,7 - t e t r a n i t ro 1 ,3 ,5,7-t e t r a z o c in e (HM X) . Pu b l i sh e d b y U.S . EPA Of f ic e o f Dr in k -in g W a te r , Wa sh in g to n , D.C . 2 0 46 0 , U.S .A.

1 2 Gr i e s t , W.H, , A J . S t e wa r t , R .L . Ty n d a l , C .H. Ho a n d E . Ta n .1 9 9 0 . Ch a ra c t e r i z a t i o n o f e x p lo s iv e s p ro c e ss in g wa s t e d e -c o m p o s i t i o n d u e t o c o m p o s t in g . In : R e p o r t N o . D O E I A C1 0 1 6 -B1 2 3 -A1 .

1 3 Lo w e , W. , R . Wi l l i a m s a n d P . Ma rk s . 1 9 89 . Co m p o s t in g o fEx p lo s iv e -Co n ta m in a t e d So i l Te c h n o lo g y . In : U .S . Arm yT o x i c a n d H a z a r d o u s M a t e r i a l s A g e n c y R e p o r t N o .C E T H A - T E - C R - 9 0 0 2 7 , U S A T H A M A , A b e r d e e n P r o v i n gG r o u n d , M a r y l a n d , U . S . A .

composting of explosives and propellant contaminated soils under

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