• 한국지하수토양환경학회지:지하수토양환경
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• 제28권1호
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• pp.1-14
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• 2023

In this study, column tests using relatively uniform Jumunjin sand media were conducted to evaluate the feasibility of calcium polysulfide (CaS_x, CPS) in removing high concentration of Zn²⁺ in groundwater. The injected CPS solution reacted rapidly with Zn²⁺ in artificial groundwater and effectively reduced Zn²⁺ by more than 99% through metal sulfide precipitation. Since the density (d = 1.27 g/cm³ ) of CPS solution was greater than that of water, CPS solution settled down rapidly while capturing Zn²⁺ and formed stable CPS layer similar to dense nonaqueous phase liquid. Mass balance analysis on Zn²⁺ in CPS solution suggested that CPS solution effectively reacted with Zn²⁺ to form metal sulfide precipitates except for high groundwater seepage velocity of 400 cm/d. With greater groundwater seepage velocity, injected CPS did not completely dissolve at the CPS-water interface, but a partially-misible CPS layer continuously moved and reacted with Zn²⁺+ in the direction of groundwater flow. Since hydraulic conductivity (K_h) decreased slightly due to the generated metal precipitates in the inter-pores of media, injection of CPS solution should be optimized to prevent clogging. As evidenced by both XRF and SEM/EDS results, ZnS precipitates were clearly observed through the reaction between the CPS solution and Zn²⁺. Further study is warranted to evaluate the feasibility of CPS to remove high-concentration heavy metalcontaminated groundwater in complex and heterogeneous media.

• 농약과학회지
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• 제7권4호
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• pp.280-287
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• 2003

주요 토양 처리용 농약 (10종 원제)의 지렁이에 대한 급성독성시험을 실시하여 노출을 고려한 위해성을 평가한 결과 paraquat dichloride와 pendimethalin은 지렁이에 대한 위해성이 무시할 수 있는 수준으로, benfuracarb, cadusafos, chlorpyrifos-methyl, endosulfan, isazofos, parathion 등 6종은 위해성이 낮은 것으로 그리고 imidacloprid와 phorate는 위해성이 높은 것으로 평가하고 번식독성시험이 필요한 것으로 판단되었다. 토양중 추정농도가 높은 22종 제품농약의 경우 인공토양을 이용한 독성시험 결과 dazomet 98% GR과 metam-sodium 25 % SL은 기준량 및 배량처리구에서 모두 치사하여 지렁이에 대한 영향이 높은 것으로, calcite 95% WP, calcium polysulfide 36% CF, chlorothalonil 75% WP, daminozide 85% WP, dichlonil 6.7% GR, etridiazole 25% EC, fosetyl-Al 80% WP, glyphosate 41% SL, hymexazo1 30% SL, iprodione 50% WP, machine oil 95% EC, mancozeb 75% WP, metam-sodium 25% SL, propineb 70% WP, terbuthylazine 80% WP, triazophos 40% EC는 지렁이에 대한 영향이 없는 것으로 나타났으나, thiophanate-methyl 70% WP, copper hydroxide 77% WP, dimethoate 46% EC, tolclofos-methyl 50% WP 및 propamocarb hydrochloride 67% SL 등 5 농약은 영향여부가 불분명하여 아만성독성시험을 수행한 결과 thiophanate-methy1 70% WP는 기준량 이상 처리시 지렁이에 치사 등 영향을 나타냈으나, copper hydroxide 77% WP, dimethoate 46% EC, tolclofos-methyl 50% WP 및 propamocarb hydrochloride 67% SL는 지렁이에 대한 영향이 낮은 것으로 조사되었다.