Khan Bernine I, Jambeck Jenna, Solo-Gabriele Helena M, Townsend Timothy G, Cai Yong
Department of Civil, Architectural, and Environmental Engineering, University of Miami, P.O. Box, 248294, Coral Gables, Florida 33124-0630, USA.
Environ Sci Technol. 2006 Feb 1;40(3):994-9. doi: 10.1021/es051471u.
Wood treated with chromated copper arsenate (CCA) is primarily disposed within construction and demolition (C&D) debris landfills, with wood monofills and municipal solid waste (MSW) landfills as alternative disposal options. This study evaluated the extent and speciation of arsenic leaching from landfills containing CCA-treated wood. In control lysimeters where untreated wood was used, dimethylarsinic acid (DMAA) represented the major arsenic species. The dominant arsenic species differed in the lysimeters containing CCA-treated wood, with As(V) greatest in the monofill and C&D lysimeters and As(III) greatest in the MSW lysimeters. In CCA-containing lysimeters, the organoarsenic species monomethylarsonic acid (MMAA) and DMAAwere virtually absent in the monofill lysimeter and observed in the C&D and MSW lysimeters. Overall arsenic leaching rate varied for the wood monofill (0.69% per meter of water added), C&D (0.36% per m), and MSW (0.84% per m) lysimeters. Utilizing these rates with annual disposal data, a mathematical model was developed to quantify arsenic leaching from CCA-treated wood disposed to Florida landfills. Model findings showed between 20 and 50 t of arsenic (depending on lysimeter type) had leached prior to 2000 with an expected increase between 350 and 830 t by 2040. Groundwater analysis from 21 Florida C&D landfills suspected of accepting CCA-treated wood showed that groundwater at 3 landfills was characterized by elevated arsenic concentrations with only 1 showing impacts from the C&D waste. The slow release of arsenic from disposed treated wood may account for the lack of significant impact to groundwater near most C&D facilities at this time. However, greater impacts are anticipated in the future given that the maximum releases of arsenic are expected by the year 2100.
经铬酸铜砷酸盐（CCA）处理的木材主要被处置在建筑与拆除（C&D）垃圾填埋场，木材专用填埋场和城市固体废物（MSW）填埋场则作为替代处置选项。本研究评估了含有CCA处理木材的填埋场中砷的浸出程度和形态。在使用未处理木材的对照渗漏计中，二甲基砷酸（DMAA）是主要的砷形态。在含有CCA处理木材的渗漏计中，主要的砷形态有所不同，在专用填埋场和C&D渗漏计中As(V)含量最高，而在MSW渗漏计中As(III)含量最高。在含有CCA的渗漏计中，有机砷形态一甲基砷酸（MMAA）和DMAA在专用填埋场渗漏计中几乎不存在，而在C&D和MSW渗漏计中被检测到。木材专用填埋场（每添加一米水浸出率为0.69%）、C&D（每米0.36%）和MSW（每米0.84%）渗漏计的总体砷浸出率各不相同。利用这些浸出率和年度处置数据，开发了一个数学模型来量化处置到佛罗里达填埋场的CCA处理木材中的砷浸出量。模型结果显示，在2000年之前已经有20至50吨砷（取决于渗漏计类型）浸出，预计到2040年将增加350至830吨。对21个疑似接收过CCA处理木材的佛罗里达C&D填埋场的地下水分析表明，3个填埋场的地下水中砷浓度升高，只有1个显示受到C&D废物的影响。处置的处理木材中砷的缓慢释放可能是目前大多数C&D设施附近地下水未受到重大影响的原因。然而，鉴于预计到2100年砷的释放量将达到最大值，未来预计会有更大的影响。
