Austin Bradley J, Scott Erin, Massey Leslie, Evans-White Michelle A, Entrekin Sally, Haggard Brian E
Biological and Agricultural Engineering Department, University of Arkansas, Fayetteville, AR, USA.
Arkansas Water Resources Center, UA Division of Agriculture, Fayetteville, AR, USA.
Environ Monit Assess. 2017 May;189(5):209. doi: 10.1007/s10661-017-5904-8. Epub 2017 Apr 6.
The Fayetteville Shale within north central Arkansas is an area of extensive unconventional natural gas (UNG) production. Recently, the Scott Henderson Gulf Mountain Wildlife Management Area (GMWMA) was leased from the state of Arkansas for NG exploration, raising concerns about potential impacts on water resources. From November 2010 through November 2014, we monitored four reaches of the South Fork Little Red River (SFLRR), within the GMWMA, establishing baseline physico-chemical characteristics prior to UNG development and assessing trends in parameters during and after UNG development. Water samples were collected monthly during baseflow conditions and analyzed for conductivity, turbidity, ions, total organic carbon (TOC), and metals. All parameters were flow-adjusted and evaluated for monotonic changes over time. The concentrations of all constituents measured in the SFLRR were generally low (e.g., nitrate ranged from <0.005 to 0.268 mg/l across all sites and sample periods), suggesting the SFLRR is of high water quality. Flow-adjusted conductivity measurements and sodium concentrations increased at site 1, while magnesium decreased across all four sites, TOC decreased at sites 1 and 3, and iron decreased at site 1 over the duration of the study. With the exception of conductivity and sodium, the physico-chemical parameters either decreased or did not change over the 4-year duration, indicating that UNG activities within the GMWMA have had minimal or no detectable impact on water quality within the SFLRR. Our study provides essential baseline information that can be used to evaluate water quality within the SFLRR in the future should UNG activity within the GMWMA expand.
阿肯色州中北部的费耶特维尔页岩气田是一个非常规天然气（UNG）广泛开采的地区。最近，斯科特·亨德森海湾山区野生动物管理区（GMWMA）被从阿肯色州租赁用于天然气勘探，这引发了人们对水资源潜在影响的担忧。从2010年11月到2014年11月，我们对GMWMA内的小红河南支流（SFLRR）的四个河段进行了监测，在非常规天然气开发之前建立了理化特征基线，并评估了非常规天然气开发期间及之后各项参数的变化趋势。在基流条件下每月采集水样，分析其电导率、浊度、离子、总有机碳（TOC）和金属含量。所有参数都进行了流量校正，并评估了随时间的单调变化。SFLRR中测量的所有成分浓度普遍较低（例如，在所有站点和采样期间，硝酸盐浓度范围为<0.005至0.268毫克/升），这表明SFLRR的水质很高。在研究期间，站点1的流量校正电导率测量值和钠浓度增加，而所有四个站点的镁含量均下降，站点1和3的TOC下降，站点1的铁含量下降。除电导率和钠外，理化参数在4年期间要么下降，要么没有变化，这表明GMWMA内的非常规天然气活动对SFLRR内的水质影响极小或未被检测到。我们的研究提供了重要的基线信息，未来如果GMWMA内的非常规天然气活动扩大，这些信息可用于评估SFLRR内的水质。
