PLANT GROWTH EFFECTS OF COAL COMBUSTION PRODUCT AMENDMENT TO MINE SPOILS AND ASSOCIATED LEACHING POTENTIALS 1

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1 PLANT GROWTH EFFECTS OF COAL COMBUSTION PRODUCT AMENDMENT TO MINE SPOILS AND ASSOCIATED LEACHING POTENTIALS 1 Michel A. Beck 2, W. Lee Dniels nd Mtt J. Eick Astrct: Reserch on the eneficil utiliztion of col comustion products (CCPs) s surfce mendments in mining environments hs focused upon ulk cid-se lnces nd hevy metl (Cu, Zn, Fe, Al, Mn, etc.) moility to locl groundwter. Currently, the pulic nd regultory communities re plcing greter focus on the potentil of As, B nd Se moility from CCP utiliztion. Five CCPs were selected from regionl set of 28 mterils following complete chemicl chrcteriztion for greenhouse iossy trils. Acidic sndstone mine spoil ws mended t 0, 10, nd 20% (v:v) with the CCPs. The iossy tril ws designed to test the presumed effectiveness of CCPs s surfce-pplied mendments to mine soils for improving ph nd wter holding cpcity. The procedures were modified to include pour-through protocol where we leched greenhouse pots with excess wter strting one month fter estlishment of the tril, nd then collected lechtes for nlyses of ph, EC, As, B, Se nd other prmeters. The tril ws conducted using soyen (Glycine mx) s n indictor plnt sensitive to sustrte chemicl conditions (EC, ph, elementl toxicity) nd tll fescue (Festuc rundincee) s species exhiiting reltive tolernce to low ph, metls, nd slts. Tll fescue dry mtter yield tended to increse with incresing CCP rte s long s the ulk soil ph remined t ph 8.0 or less. Depending on the liming cpcity (s mesured y clcium cronte equivlence - CCE) of the CCP pplied, the 20% ppliction hd the gretest positive effect on plnt yield (e.g. t CCE = 7.7). However, in cse of CCP with high liming potentil (CCE = 47.7), 5% ppliction ws most eneficil to dry mtter yield. The EC nd ph from vrious mixes relted well to CCE of the respective CCP nd the loding rte. Leching of oxynion forming elements (As, Mo, Se) under these soil conditions nd loding rtes does not pper to e concern, lthough some Se ws oserved in the first lechtes. As expected, B long with S (s SO 4 2- ) were the two elements t highest concentrtion in the lechtes. However, correltion nd stepwise regression nlysis of yield dt with the elementl concentrtions from the pour-through solutions indicted these two elements did not negtively ffect fescue yield. However, stepwise regression nlysis did show tht fescue yield ws ffected y ph (p > ). Our comined results indicte tht few reltively simple l mesurements (ph, EC, CCE) coupled with simple soyen iossy such s reported here cn redily predict oth the reltive effectiveness nd potentil toxicity of given CCP when used s either ulk mine soil mendment or n lkline dditive for mine soil cidity control. Additionl Key Words: Fly sh, flue gs desulfuriztion sludge, eneficil use, phytotoxicity. 1 Pper ws presented t the 2008 Ntionl Meeting of the Americn Society of Mining nd Reclmtion, Richmond, VA, New Opportunities to Apply Our Science June 14-19, R.I. Brnhisel (Ed.) Pulished y ASMR, 3134 Montvest Rd., Lexington, KY M.A. Beck, Senior Reserch Associte, W.L. Dniels, Professor, nd Mtt Eick, Assoc. Professor, respectively, Dept. of Crop & Soil Env. Sci., 0404, Virgini Tech, Blcksurg, VA Emil: mikeeck@vt.edu. 112

2 Introduction Utiliztion of col fly sh nd flue gs desulfuriztion (FGD) mterils s soil mendments is limited y their vriility in chemicl properties nd interction with soils. Development of utiliztion guidnce for one-time or multiple pplictions of col comustion products (CCPs) to different soils/sustrtes (griculturl soil, mine spoil, or col refuse) would e eneficil for the utiliztion of vst quntities of fly sh creted y col-fired power plnts. Previous work y our group on CCPs (Dniels et l., 1996 & 2002; Stewrt et l., 1997) focused primrily on potentil wter qulity enefits nd risks of fly sh utiliztion in vrious mine environments, with principl focus upon ulk cid-se lnces nd hevy metl (Cu, Zn, Fe, Al, Mn, etc.) moility to locl groundwter. However, the possiility of As, Mo, nd Se moility in sh/mine spoil lechtes were not evluted minly ecuse of lck of regultory concern t the time. Currently, the pulic nd the environmentl regultory community re plcing much greter focus on the potentil for As, B, Mo nd Se moility from CCP utiliztion on/in ctive col mines, long with strong emphsis on defining Hg levels nd moility in col comustion products in generl. As n exmple, the USEPA recently reffirmed its 1993 position exempting CCPs from regultion s Resource Conservtion nd Recovery Act (RCRA) sutitle C (toxic) wstes, ut specificlly reserved judgment on the use of CCPs in col mining environments. In April of 2006, in response to citizen nd regultory concerns over wter qulity issues, the Ntionl Acdemy of Sciences relesed its detiled report (NRC, 2006) on potentil mine site impcts of CCP utiliztion. While the report did offer overll support for eneficil utiliztion of CCPs in mining environments, it specificlly cutioned potentil permittees to: (1) Crefully chrcterize the geochemicl properties of the CCP to e utilized; (2) understnd nd predict long-term rections nd contminnt relese ptterns; nd (3) fully chrcterize potentil site hydrologic impcts. Thus, the prediction of the reltive moility of As, B, Mo, Se, nd other potentilly wter solule trce ions is the current focus of our continuing coopertive reserch progrm. As prt of our erlier coopertive efforts with the Virgini Division of Mined Lnd Reclmtion (VDMLR), nd the Virgini Deprtment of Environmentl Qulity (DEQ) in the 1990 s (see Dniels et l., 2002), we developed routine nd inexpensive greenhouse iossy pproch to screening plnt growth effects of vrious lnd pplied residuls. The protocol uses soyens nd tll fescue grown in mine spoil or ntive soil sustrte which is mended with 113

3 vrious rtes of the CCP proposed for eneficil use. Therefore, the overll ojectives of this study were: 1. To predict the reltive iovilility/leching risk of As, Se, nd B in common southwestern Virgini col mining/ccp utiliztion environments. 2. To test comined lortory nd greenhouse screening technique to predict the eneficil use potentil of CCPs when used s topicl mine soil mendments nd ulklended tretments for cidic mine spoil. Mterils nd Methods We worked with industry coopertors nd collected 28 representtive composite smples of their current CCP strems from regionl utilities urning Virgini cols. The 28 primry composite smples were sujected to suite of chemicl nlyses nd chrcteriztion. Bsed on these results, five CCPs were selected for the greenhouse iossy study on the plnt growth effects of lnd-ppliction of the vrious CCPs to mined lnds. Full results on chemicl nlyses of ll 28 CCPs re ville in Dniels et l. (2006). Acidic sndstone mine spoil ws collected t n ctive Powell River/Red River surfce col mine in Wise County, Virgini (lortory ph = 4.75, with liming requirement of 4.5 Mg/h). The mine spoil ws ir dried nd sieved to pss 2 mm sieve. Col Comustion Products nd Mine Spoil Anlyses All nlyses were conducted in triplicte except for the Toxicity Chrcteristic Lechte Procedure (TCLP) which is conducted on lrge (50 g) ulk smple s indicted y USEPA. ph nd Electricl Conductnce (EC, n indirect mesurement of slt content; Rhodes, 1982) were determined on sturted pste extrcts of CCPs. The CCP ws mixed with distilled DI wter until it formed glistening pste. The pste ws filtered fter 1 hr equilirtion nd the filtrte nlyzed for ph nd EC. Hot CCl 2 extrctle B (Binghm, 1982) ws determined y oiling 20ml 0.01M CCl 2 with 10g sh for 10 minutes. The filtrte ws nlyzed y ICPES for totl B. Totl elementl nlysis ws determined y microwve digestion of 0.5 g CCP with 3 ml concentrted HCl nd 9 ml concentrted HNO 3. The extrct ws rought up to 50 ml volume with distilled DI wter nd nlyzed y ICPES (U.S. EPA, 1996). 114

4 We used the TCLP test for priority elements (U.S. EPA, 1992). Mehlich-1 extrction (0.05M HCl M H 2 SO 4 ) ws utilized for extrctle P, C, B, nd Fe (Mehlich, 1953) followed y ICPES (Type FTMOA85D, Spectro Anlyticl Instruments, Inc). We completed nlyses of the primry composite smples of 28 CCPs s outlined ove. The overll results re discussed elow long with our rtionle for selection of five CCPs (4 fly shes nd 1 FGD) tht we felt est represented the overll nlyzed smple set. These five mterils were then used in the greenhouse plnt growth iossy tril nd pot leching procedure. Methods for Greenhouse Biossy Tril Generl design, methods, nd techniques used for our greenhouse iossy (mine soil mendment scenrio) re fully documented nd cited y Dniels et l. (2002 nd 2006). The procedures were modified to include pour-through protocol (Wright, 1986) where we eluted greenhouse pots with excess leching wters pproximtely one month fter estlishment of the tril, nd then collected the lechtes for nlyses including ph, EC, As, B, Cr, Mo, nd Se. The tril ws conducted using soyens (Glycine mx) s n indictor plnt sensitive to sustrte chemicl conditions (EC, ph, elementl toxicity) nd tll fescue (Festuc rundincee) s test crop exhiiting reltive tolernce to low ph, metls, nd slts. Experimentl Design & Tretments: Trils were conducted seprtely for fescue nd soyens. The sttisticl design ws completely rndomized lock (CRB) with 4 replictions per tretment comintion. CCP rtes: 5%, 10%, 20% (v:v sis, ut mesured on weight sis to reduce vriility) s well s 100% mine spoil control pots for ech crop Volume of sustrte / pot = 700 ml / pot (900 g pot -1 ) 3 sh rtes X 5 CCP s X 2 crops X 4 replictions Control pots: Control (-) no-lime mine spoil only (4 per crop) Limed control (+) pots (4.5 Mg h -1 equivlent) Highly limed control (++) pots (9 Mg h -1 equivlent) 115

5 Approximtely every month, pots were llowed to equilirte t field cpcity for 24 hours nd then eluted with excess wter to otin 50 ml (± 5 ml) of lechte. This is modifiction of the pour-through technique of Wright (1986). Soyen pots were seeded (4 seeds per pot) nd susequently thinned to the helthiest plnt of ech pot 1 month fter seeding. Fescue ws cut, dried, nd weighed pproximtely every 3 weeks. Overll fertility ws mintined with periodic fertigtion using Peter s liquid fertilizer t 75 µg N ml -1. Results nd Discussion CCP Chemicl Properties We otined set of 28 CCPs with wide rnge of importnt chemicl properties s detiled y Dniels et l. (2006). While the rnge in ph ws 3.57 to 12.35, only 3 CCPs hd ph elow 7. Solule slt content of CCPs lso vried gretly with rnge of EC of 0.66 to ds m -1 ; however, the distriution ws more uniform cross the rnge thn for ph. The liming cpcity of the CCPs rnged from 0 to 52% CCE, nd tended to e either low (<10%) or high (>30%), with only 6 CCPs in the 10 to 30% rnge. Of the 28 CCPs tested, 14 hd CCE of <5%. Using the dt sets discussed ove, we ctegorized the 28 mterils into somewht modified 2 X 2 mtrix of As levels (low nd high) y CCE (levels low nd high). Electricl conductnce (EC) ws strong covrite. Low CCE shes exist with high nd low EC, nd high CCE mterils exist with high nd low EC. Five CCPs were selected from the lrger smple set for greenhouse iossy study. The selection criteri for the 5 CCPs chosen for the greenhouse iossy tril re given in Tle 1. Results of the TCLP nlysis (dt not shown) on the five CCPs indicted tht ll elements of concerns were elow EPA criticl limits y fctor of 10 or greter. Mercury ws elow detection limits in the TCLP test extrcts. However, mjor limittion to most l tests (like TCLP) designed to simulte element relese (leching) is tht these tests do not provide informtion on ctul relese under wide rnge of expected disposl or lnd ppliction geochemicl environments (NRC, 2006). In the cse of highly lkline fly sh or non-cidic col refuse, for exmple, the TCLP procedure tests these mterils in modertely cidic (glcil cetic cid) environment. This extrction environment my e drsticlly different from the conditions governing lechility under ctul co-disposl conditions, nd we hve previously 116

6 reported (Stewrt et l., 2001) significnt metl leching from fly sh mterils tht esily pssed the TCLP test. Tle 1. CCPs selected for greenhouse iossy tril. Ash # Type of Ash Ash properties 11 Fly sh High As, low CCE, low EC, high extr. B. 28 Fly sh High As, low CCE, mod. high EC, low extr. B. 16 Fly sh Low As, high CCE, low EC, low extr. B. 27 Fly sh Low As, high CCE, high EC, low extr. B. 7 FGD Rel. low As, high CCE, mod. EC, med. extr. B. Generl chemicl properties nd totl elementl concentrtions of As, Se, Cr, nd Mo otined y totl digestion of the five selected CCPs re presented in Tle 2. The dt show mjor differences in liming cpcity (CCE) nd slt contents of the CCPs nd revel some implictions of these properties upon mixing with slightly cidic mine spoil. While CCP #11 hs sustntilly higher totl As content thn the other CCPs, the mixing of these shes t the reltively low mendment rtes will result in only very low levels of As dditions, nd even lower levels of ioville As. In seprte study (Dniels et l., 2006) on the chemicl properties of the 28 CCPs we found tht in generl, < 30% of totl As is in exchngele nd cronte forms which re considered ioville (Tessier et l., 1979). The results of the soil test nlysis y Mehlich-1 extrction of the vrious lends of mine spoil mended with the respective CCPs re presented in Tle 3. Ashes # 16 nd 27 hd very strong liming effect on the mine spoil. Even the 5% mendment rte rised the soil ph to >10. Depending on the plnt species, this could hve very negtive effect on plnt growth. However, from plnt nutrition stndpoint, the CCP mendments did not pper to ffect sustrtes to the point where ny element ws clerly phytotoxic. 117

7 Tle 2. Chemicl properties of five CCPs selected for use in greenhouse iossy experiments. Sturted Pste Totl Elementl Anlysis CCP Bd ph EC CCE Extr. B Totl B As Se Cr Mo # g cm -3 ds m -1 % mg L -1 mg kg -1 mg kg -1 mg kg -1 mg kg -1 mg kg Bd = Dry ulk density Tle 3. Selected Mehlich-1 extrctle chemicl properties of CCPs, mine spoil, nd CCP mended mine spoil t the onset of the iossy greenhouse tril. Mine spoil + 2 : mg kg % of CCP ph Zn Mn B Cu Fe P Mg Mine spoil #7 100% #11 100% #16 100% #27 100% #28 100% #7 5% #7 10% #7 20% #11 5% #11 10% #11 20% #16 5% #16 10% #16 20% #27 5% #27 10% #27 20% #28 5% #28 10% #28 20% Greenhouse Biossy Experiment Dry mtter yields from the first cutting (30 dys) of tll fescue, long with corresponding lechte EC nd ph from the pots t tht time, re presented in Fig. 1 nd Tle 4,. Dry mtter yield tended to increse with incresing CCP rte s long s the ulk soil ph remined t ph 8.0 or less. Depending on the liming cpcity (s indicted y CCE) of the CCP pplied, the 20% ppliction hd the gretest positive effect on plnt yield (e.g. see CCP # 28 with CCE of 7.7). 118

8 Dry mtter (g/pot) A. Effect of CCP type nd rte on fescue yield (cutting # 1) Control CCP # 5% CCP 10% CCP 20% CCP Lechte ph B. Effect of CCP type nd rte on lechte ph from fescue pots c c Control CCP # 5% CCP 10% CCP 20% CCP Lechte EC (ds m-1) C. Effect of CCP type nd rte on lechte EC from fescue pots Control CCP # 5% CCP 10% CCP 20% CCP Figure 1. Tll fescue dry mtter yield nd corresponding ph nd EC from pot lechtes. Note: for Controls, the 5% corresponds to no-lime, 10% to low lime (4.5 Mg/h), nd 20% to high lime (9 Mg/h). For ech CCP #, rs with differing letters for ech CCP re different t p <

9 However, in cse of CCPs with high liming potentil (e.g. #27, CCE = 47.7), 5% ppliction ws most eneficil to dry mtter yield. Higher mendment rtes (10 & 20%) of CCPs with high liming cpcities elevted the sustrte ph ove 8.0 which limited or decresed plnt yield. The limited CCE of CCP #11 nd #28 ws reflected in the limited liming effect nd lower ph of the pour-through lechte solutions. Results from the soyen tril re given in Fig. 2 nd indicte similr overll response to the vried CCP mendments fter 32 dys of growth. Yields incresed with incresing mendment rtes for CCPs # 11 nd 28, ut there were either no effect, or ctul yield decreses for ll other CCPs nd for the highest liming rte in the control pots. Results of the nlysis of vrince (ANOVA) of the fescue nd soyen yield dt reveled highly significnt effects of oth CCP source nd ppliction rte (Tle 5). The sme highly significnt effects were oserved for EC nd ph, except tht for these two vriles, the CCP source y ppliction rte interction (CCP x rte) ws lso highly significnt (ANOVA results not shown). Pour-through dt for the soyen pots (not shown) indicted tht EC vlues significntly exceeded the criticl limit (for slt sensitive species) of 2 ds m -1 in pots treted with CCP # 7, nd, slightly exceeded the limit for CCP # s 11, 16 nd 28. While the CCPs differed widely in their totl elementl composition (Tle 2), the dominnt chemicl property with wide rnging effect ws CCE. This property (CCE) through its effect on ph controls the soluility nd/or relese of the elements of interest, either from the dded CCP or from the mended mine spoil. This is most evident for the Cr nd Mo from the pour-through dt of the tll fescue pots (Tle 4). Once the sustrte ph exceeds 8, greter concentrtions of these elements re oserved in the lechte solutions. Yield reductions nd plnt stress symptoms re likely due to fctors such s exceedingly high ph nd EC (reduced yield with highest liming rte in control pots), high concentrtions of B, Se, nd Mo, nd/or comintions of these fctors. 120

10 A. Effect of CCP type nd rte on soyen yield Dry mtter (g/pot) % CCP 10% CCP 20% CCP Control CCP # B. Effect of CCP type nd rte on lechte ph from soyen pots Lechte ph % CCP 10% CCP 20% CCP Control CCP # Lechte EC (ds m-1) C. Effect of CCP type nd rte on lechte EC from soyen pots Control CCP # 5% CCP 10% CCP 20% CCP Figure 2. Soyen dry mtter yield nd corresponding ph nd EC from pot lechtes. Note: for Controls, the 5% corresponds to no-lime, 10% to low lime (4.5 Mg/h), nd 20% to high lime (9 Mg/h). For ech CCP #, rs with different letters re different t p <

11 Tle 4. Fescue grss clipping yields (g pot -1 ) nd pour-through lechte ph, EC (ds m -1 ), nd As (mg L -1 ) from cidic mine spoil mended with vrious CCPs t 0, 5, 10, or 20% (v:v) nd seeded to tll fescue. Oservtions from 3 pour-through events nd ssocited hrvest of grss clippings Yield ph EC As CCP# CCP rte % <0.024 <0.024 < % <0.024 < % <0.024 <0.024 < % <0.024 < % <0.024 < % <0.024 <0.024 < % <0.024 < % <0.024 < % <0.024 <0.024 < % <0.024 <0.024 < % <0.024 < % <0.024 <0.024 < % <0.024 <0.024 < % <0.024 <0.024 < % <0.024 <0.024 <0.024 Control <0.024 <0.024 <0.024 Control <0.024 <0.024 <0.024 Control <0.024 <0.024 <0.024 Denotes pour-through events 1 3. Note: Vlues listed s < denote detection limit for prmeter/instrument employed. 122

12 Tle 4. Pour-through lechte concentrtions (mg L -1 ) of selected elements from cidic mine spoil mended with vrious CCPs t 0, 5, 10, or 20% (v:v) nd seeded to tll fescue. Oservtions from 3 pour-through events nd ssocited hrvest of grss clippings Cr Mo B Se CCP# CCP rte % <0.004 < <0.008 <0.010 < <0.024 < % <0.004 < <0.024 < % < <0.024 < % <0.004 <0.004 < < <0.024 < % <0.004 <0.004 < <0.024 < % <0.004 <0.004 < <0.024 < % <0.004 <0.004 <0.002 <0.008 <0.010 < <0.024 < % <0.004 <0.002 <0.008 <0.010 < < % <0.004 <0.004 <0.002 <0.008 < <0.024 < % <0.024 < % % <0.024 < % <0.024 < % <0.024 < % <0.024 <0.024 Control - 0 <0.004 <0.004 <0.002 <0.008 <0.010 < <0.024 <0.024 <0.024 Control + 0 <0.004 < <0.008 <0.010 <0.018 < < <0.024 <0.024 Control++ 0 <0.004 < <0.008 <0.010 <0.018 < <0.024 <0.024 Note: Vlues listed s < denote detection limit for prmeter/instrument employed. 123

13 Tle 5. Anlysis of vrince (ANOVA) of dry mtter yield for tll fescue (cuttings # 1-3) nd soyens from iossy trils Source df Fescue 1 Fescue 2 Fescue 3 Soyen Pr > F vlue Rep 3 ns ns ns ns CCP 7*.001 <.0001 < Rte 3 ns ns CCP x rte 8 ns ns ns.02 * df (n-1) = 5 for CCPs nd 3 control tretments Visul symptoms of stress nd phytotoxicity (Figs. 3 nd 4) on plnts due to different CCPs nd mendment rtes confirmed the susceptiility of soyens versus tll fescue. Soyens showed moderte to severe chlorosis nd necrosis in ll tretments other thn the 5% rte of CCPs # 11 (low in CCE) nd #16 (low extrctle B). Overll, ffected soyen plnts looked very unhelthy nd stunted in growth in the 10% nd 20% tretments. Tll fescue, on the other hnd, displyed symptoms of chlorosis nd necrosis on the tips (Fig. 5) for only the 10 nd 20% rtes of high CCE shes (# 16 nd 27). Furthermore, those symptoms disppered over time nd were not noticele fter the third hrvest. Figure 3. Soyen plnt growing in cidic mine soil mended with 5% of CCP # 28. Note mrginl necrosis nd chlorosis of lower leves; typicl of comined solule slt + B dmge. 124

14 Figure 4. Soyen plnt growing in cidic mine soil mended with 10% of CCP # 16. Note hevy stunting nd complete loss/drop of lower leves; typicl of hevy solule slt + B dmge. Also note dropped leves in pot tht were totled in yield estimtes for Fig. 4. Figure 5. Tll fescue growing in cidic mine soil mended with 20% of CCP # 27 fter 30 dys. Note slight tip urn due to comined slts+b effect. Solule slt effects were not noticed t lter smpling dtes. 125

15 Comined plnt yield nd lechte dt from control smples confirmed tht the sndstonederived mine soil utilized ws reltively inert sustrte with respect the relese or leching of the elements of interest. The slight rise in ph of no-lime control smples (likely due to the irrigtion wter nd fertilizer solution) indictes its very low uffering cpcity. The qurtzitic composition of this cidic sndstone mine spoil indictes there will e little relese of ny element of concern even with drstic ph chnges due to hevy mendment with CCPs. Any relese of elements of concern would presumly come from the mending CCP. Overll, fescue nd soyen growth dt reveled highly significnt effects of oth CCP type nd ppliction rte, nd the two species (soyens vs. fescue) exhiited cler differences in tolernce to growth sustrte chemicl properties. Using lechte pour-through dt from soyen pots long with the dt from pre- nd post-hrvest nlysis of the growth sustrtes, we could not single out ny individul element s directly limiting overll soyen yield. Sustrte ph, s function of CCE ws the dominnt chemicl property ffecting reltive plnt growth. CCE directly controls the sustrte ph nd consequently the soluility nd/or relese of the elements of interest, e it from the CCP or the mended mine spoil. Plnt ppernce nd visul toxicity symptoms, prticulrly on soyens, were very good nd consistent indictor of pprent stress to the plnts, while overll iomss yield ws not s good of n indictor. Conclusions The vrious components of this study represent multi fceted ttempt to predict reltive lechility/iovilility of As, Cr, Mo, Se, nd B from CCPs s mine soil mendments nd their effect on plnt growth. The pproch includes lortory nlyses nd greenhouse iossy method for screening of CCPs s potentil mendments. Results indicte tht net CCE is the most importnt chrcteristic of CCPs tht ffects iovilility or lechility for most elements of concern. The CCE is the criticl property tht determines the ulk ph of the CCPs, ut lso ffects the ph of the mended mine soil nd therey hs predominnt impct on plnt growth nd the iovililty/lechility of vrious oxynions nd hevy metls. The importnce of predicting nd dding dequte totl lklinity (CCE) to completely offset ulk cidifiction of CCP/mine spoil lends ws demonstrted here with decresed plnt growth when the sustrte ph exceeded 8.0. The criticl issue is whether or not sufficient nd/or pproprite totl lklinity is loded into the system for long-term nd permnent cid control. Our 126

16 comined results indicte tht few reltively simple l mesurements (ph, EC, CCE) coupled with simple soyen iossy such s reported here cn redily predict oth the reltive effectiveness nd potentil toxicity of given CCP when used s either ulk mine soil mendment or n lkline dditive for cid control. Acknowledgments This work ws generously supported y the USDI-OSM Applied Reserch Progrm nd y Virgini Tech s Powell River Project. Butch Lmert with VDMLR nd Kim Vories nd Lois Urnowski with OSM were ctive supporters of this project. The ssistnce of W.T. Price nd Julie Burger in the l nd the field is grtefully cknowledged. We lso pprecite our collegues in t regionl electric utilities nd other col-fired plnts who provided CCP smples for nlysis. Literture Cited Binghm, F.T Boron. In Methods of soil nlysis, Prt 2. Chemicl nd Microiologicl Properties. ASA-SSSA. Dniels, W.L., B.R. Stewrt, nd D. Dove Powell River Project Reclmtion Guidelines for surfce-mined lnd in Southwest Virgini. Reclmtion of col refuse disposl res. Virgini Coop. Ext. Pu Aville on-line t html. Dniels, W.L., B.R. Stewrt, K.C. Hering nd C.E. Zipper The Potentil for Beneficil Reuse of Col Fly Ash in Southwest Virgini Mining Environments. Puliction Numer , V. Coop. Extension Service, Blcksurg. Dniels W.L., M. Beck, nd M. Eick Development of Rpid Assessment Protocols for Beneficil Use of Post-2000 Col Comustion Products in Virgini Col Mines. 57 p. Description: Finl report to USDI OSM for Applied Science Progrm. USDI OSM, Prkwy Center, Pittsurgh. Mehlich, A Determintion of P, C, Mg, K, N, nd NH 4. North Crolin Soil Test Division (Mimeo 1953). 127

17 NRC, Mnging Col Comustion Residues in Mines, Ntionl Reserch Council, Ntionl Acdemy Press, Wshington, D.C. ( html). Rhodes, J.D Solule slts. In Methods of soil nlysis, Prt 2: Chemicl nd microiologicl properties - Agronomy Mono. No. 9. ASA-SSSA, Mdison, WI, USA. Stewrt, B.R., W.L. Dniels nd M.L. Jckson Evlution of lechte qulity from the codisposl of col fly sh nd col refuse. J. Env. Qulity 26; Stewrt, B.R., W.L. Dniels, L.W. Zelzny nd M.L. Jckson Evlution of lechtes from col refuse lended with fly sh t different rtes. J. Env. Qul. 30: Tessier, A., P.G.C. Cmpell, nd M. Bisson Sequentil extrction procedure for the specition of prticulte trce metls. Anl. Chem. 51:7, U.S. EPA Toxicity chrcteristic leching procedure. Method 1311, Test Methods for Evluting Solid Wste: Physicl/Chemicl Methods (SW-846), 35pp. U.S.EPA, SW-846 Acid Digestion of Sediments, Sludges, nd Soils, Method 3050B. Wright, R.D The pour-through nutrient extrction procedure. HortScience 21: