Groundwater最新文献

{"title":"Modeling the Influence of Coastal Site Characteristics on PFAS in Situ Remediation","authors":"Grant R. Carey,&nbsp;Anthony Danko,&nbsp;Anh Le-Tuan Pham,&nbsp;Keir Soderberg,&nbsp;Beth Hoagland,&nbsp;Brent Sleep","doi":"10.1111/gwat.13456","DOIUrl":"10.1111/gwat.13456","url":null,"abstract":"<p>The potential performance of a hypothetical colloidal-activated carbon (CAC) in situ remedy for perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS) in groundwater in coastal zones was evaluated using estimated hydrogeologic and geochemical parameters for a coastal site in the United States. With these parameters, a reactive transport model (ISR-MT3DMS) was used to assess the effects of tidal fluctuations and near-shore geochemistry on CAC performance. The average near-shore ionic strength of 84 mM at the site was conservatively estimated to result in an increase in the adsorption of PFOA to CAC by about 50% relative to non-coastal sites with ionic strength &lt;10 mM. The modeling also confirmed the hypothesis that tidally induced groundwater flow reversals near the shore would result in the accumulation of PFOA at the downgradient edge of the CAC zone. Slow desorption of PFOA from this downgradient CAC boundary may sustain downgradient plume concentrations above a strict cleanup criterion (e.g., USEPA MCL of 0.004 μg/L), for decades; however, there was still a large PFOA mass flux reduction (&gt;99.9%) achieved after several decades at the shore. CAC longevity was substantially greater for PFOS with a similar source concentration; however, the higher PFOS distribution coefficient (<i>K</i>_<i>d</i>) in soil downgradient from the CAC zone resulted in substantially longer flushing times. It is recommended that short-term remedial action objectives for CAC remedies at coastal sites be based on mass flux reduction targets over a period of several decades, given the demonstrated challenges in trying to achieve very low cleanup criteria downgradient of a CAC zone in the short term.</p>","PeriodicalId":12866,"journal":{"name":"Groundwater","volume":"63 2","pages":"175-191"},"PeriodicalIF":2.0,"publicationDate":"2024-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/gwat.13456","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142808971","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Federal Role in Addressing Groundwater Depletion","authors":"William M. Alley,&nbsp;Sharon B. Megdal,&nbsp;Thomas Harter","doi":"10.1111/gwat.13454","DOIUrl":"10.1111/gwat.13454","url":null,"abstract":"&lt;p&gt;Groundwater depletion has been brought to the public's attention lately, beginning with a series of high-profile articles in the &lt;i&gt;New York Times&lt;/i&gt;. The articles infer the need for greater federal involvement and control over the nation's groundwater. Separately, the President's Council of Advisors on Science and Technology (PCAST) formed a working group and solicited input on “America's Groundwater Challenges.” The PCAST request suggested federal actions were needed. However, many responses raised questions and concerns about the nature and scope of such actions (PCAST &lt;span&gt;2024a&lt;/span&gt;).&lt;/p&gt;&lt;p&gt;While safeguarding groundwater is a global challenge, the most effective solutions are found at the local or regional aquifer system level. Groundwater occurs in aquifers that are highly variable in size, geology, climate, overlying land use, water quality, and water uses. The response times of groundwater systems to pumping, connections to surface water, recharge characteristics, and environmental functions also vary widely. Each groundwater system requires individual attention.&lt;/p&gt;&lt;p&gt;Most critically, effective groundwater management and governance require meaningful and continuing engagement of numerous local stakeholders in the decision-making process. People's diverse values about the environment, property rights, livelihood, individual and community economic gains, and current and intergenerational equity come into play, as do diverse perspectives and passions on how to balance the often-competing demands around groundwater use and protection. Communication and facilitation among stakeholders, decisionmakers, scientists, technical experts, and groundwater users play critical roles in structuring informed and productive conversations.&lt;/p&gt;&lt;p&gt;Consideration of these key attributes is central to achieving sustainable groundwater management. It is also important to recognize that States and Tribes have authority over the allocation and administration of rights to the use of groundwater within their borders. States and Tribes also administer groundwater quality rules, as well as federal water-quality standards if they have achieved federal delegation. As indicated by several responses to the PCAST query, any effort to impose federal oversight on groundwater pumping would face fierce opposition from states, agricultural groups, and others.&lt;/p&gt;&lt;p&gt;Indeed, PCAST in their final recommendations acknowledged that the federal government does not manage groundwater (PCAST &lt;span&gt;2024b&lt;/span&gt;). The question becomes what is the role of the federal government among a host of partners, including state, federal, tribal, regional, and local entities; nonprofits and community-based organizations; university and private researchers; water districts; industry; and landowners?&lt;/p&gt;&lt;p&gt;Among the multiple ways the federal government can help are financial assistance for managed aquifer recharge, research and support for new technology for desalination, treatment, and water ","PeriodicalId":12866,"journal":{"name":"Groundwater","volume":"63 1","pages":"4-5"},"PeriodicalIF":2.0,"publicationDate":"2024-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/gwat.13454","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142775944","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mapping the Hydrogeological Structure of a Small Danish Island Using Transient Electromagnetic Methods","authors":"Paul McLachlan,&nbsp;Mathias Ø. Vang,&nbsp;Jesper B. Pedersen,&nbsp;Rune Kraghede,&nbsp;Anders V. Christiansen","doi":"10.1111/gwat.13452","DOIUrl":"10.1111/gwat.13452","url":null,"abstract":"<p>Small island communities often rely on groundwater as their primary source of fresh water. However, the limited land area and high proportion of coastal zones pose unique challenges to groundwater management. A detailed understanding of the subsurface structure can provide valuable insights into aquifer structure, groundwater vulnerability, saltwater intrusion, and the location of water resources. These insights can guide groundwater management strategies, for example, pollution regulation, promotion of sustainable agriculture, establishment of coastal buffer zones, and re-naturalization of land cover. Ordinarily, structural characterization relies on geological mapping and boreholes, however, such approaches can have insufficient spatial resolution to aid groundwater management. In this study, transient electromagnetic (TEM) methods are used to map the subsurface of a small, 13.2 km², Danish Island. The approach successfully identified two previously unknown paleochannels, where the interface between Quaternary aquifer units and an underlying Paleogene Clay aquiclude had maximum depths of 100 and 160 m below sea level. Before this, the interface was assumed to be 15 to 25 m below sea level: therefore, these paleochannels present substantial potential groundwater resources. Resolving geological heterogeneity within the Quaternary deposits was less successful and future work will focus on addressing these limitations. Nonetheless, in several locations, evidence of saltwater intrusion was observed within the Quaternary units. This work demonstrates how TEM mapping can identify water resources, define aquifer boundaries, and aid water management decisions. Such approaches could be applied in other areas, particularly small islands, where similar groundwater challenges exist.</p>","PeriodicalId":12866,"journal":{"name":"Groundwater","volume":"63 2","pages":"280-290"},"PeriodicalIF":2.0,"publicationDate":"2024-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142635084","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Jupyter Notebooks for Parameter Estimation, Uncertainty Analysis, and Optimization with PEST++","authors":"Chanse Ford,&nbsp;Wonsook Ha,&nbsp;Katherine Markovich,&nbsp;Johanna Zwinger","doi":"10.1111/gwat.13447","DOIUrl":"10.1111/gwat.13447","url":null,"abstract":"","PeriodicalId":12866,"journal":{"name":"Groundwater","volume":"62 6","pages":"825-829"},"PeriodicalIF":2.0,"publicationDate":"2024-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142585410","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Three Ages of Water: Prehistoric Past, Imperiled Present, and a Hope for the Future","authors":"Alan E. Fryar","doi":"10.1111/gwat.13453","DOIUrl":"https://doi.org/10.1111/gwat.13453","url":null,"abstract":"","PeriodicalId":12866,"journal":{"name":"Groundwater","volume":"63 2","pages":"143-144"},"PeriodicalIF":2.0,"publicationDate":"2024-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143533611","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Interpreting Step-Drawdown Pumping Test Undergoing Confined-Unconfined Conversion with Well Loss","authors":"Lu Zhang,&nbsp;Hua Zhao,&nbsp;Ling Wang,&nbsp;Jianmei Liu,&nbsp;Qi Zhu,&nbsp;Na Li,&nbsp;Zhang Wen,&nbsp;Yizhao Wang,&nbsp;Dian Wang","doi":"10.1111/gwat.13450","DOIUrl":"10.1111/gwat.13450","url":null,"abstract":"<p>The step-drawdown pumping test often experiences a transition from confined to unconfined conditions due to the continuously increasing pumping rate. However, the current well hydraulics model has not accurately interpreted this phenomenon. In this study, we developed an analytical solution to address the confined-unconfined conversion in step-drawdown pumping tests based on Girinskii's potential and superposition theory. Additionally, a field step-drawdown pumping test featuring confined-unconfined conversion was conducted to apply the proposed analytical solution. The particle swarm optimization algorithm was employed to simultaneously estimate multiple parameters. The results demonstrate that the newly proposed solution provides a better fit to the observed drawdown in the pumping well compared to previous models. The hydrogeological parameters (<i>K</i>, <i>S</i>), well loss coefficient (<i>B</i>), and critical time for confined-unconfined conversion (<i>t</i>_<i>c</i>) were estimated to be <i>K</i> = 7.15 m/d, <i>S</i> = 6.65 × 10⁻⁵, <i>B</i> = 7.48 × 10⁻⁶, and <i>t</i>_<i>c</i> = 1152 min, respectively. Neglecting the confined-unconfined conversion in step-drawdown pumping tests leads to underestimation of drawdown inside the pumping well due to an overestimation of the aquifer thickness. After the conversion from confined to unconfined conditions, the estimated well loss coefficient decreased by 88% compared to its pre-conversion value. This highlights the necessity of adjusting the well loss coefficient in the step-drawdown pumping test model to account for confined-unconfined conversion. In summary, this study introduces a new method for interpreting parameters in step-drawdown pumping tests and provides field validation for its effectiveness.</p>","PeriodicalId":12866,"journal":{"name":"Groundwater","volume":"63 2","pages":"248-255"},"PeriodicalIF":2.0,"publicationDate":"2024-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142570799","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Remembering the Big Picture","authors":"Kenneth R. Bradbury","doi":"10.1111/gwat.13451","DOIUrl":"10.1111/gwat.13451","url":null,"abstract":"&lt;p&gt;As a practicing hydrogeologist, I have assisted many people and communities who have problem wells or water shortages. But when I recently experienced my own water shortage, I realized how much we in developed countries depend on and take for granted that the water will just be there, and will be fit to drink, when we turn on the tap. In late May of this year, thunderstorms and a few tornados rumbled across the midwestern United States, including our home in southern Wisconsin. My wife and I live in a rural area and are accustomed to thunderstorms in the spring. We are also used to occasional electric power outages, which happen three or four times a year and usually last from 15 min to an hour. So, we weren't especially surprised or worried when our lights went out during the storm. Suddenly, our home was silent except for the rain on the windows—no TV, no radio, no internet, no refrigerator, no lights—and no water, because we depend on our domestic well and pump. Our system usually holds enough water and pressure for a couple of toilet flushes and face washes, but that's it. When the blackout lasts 1 to 2 h, no problem. But when it lasts for 24, then 48, then 60 h, as it did this time, we realize how much we take our well, and our water, for granted. We had no water stockpiled. Fortunately, I was able to drive to a convenience store and purchase a few gallons of “pure spring water” to get us through the requisite drinking, face washing, and tooth brushing, but flushing the toilets was a more complicated matter. Our older home has standard toilets, which require about 7 gal per flush (unlike the newer low-flow toilets). I found myself lugging buckets of water up a hill from a nearby stream (and 7 gal weighs around 58 pounds) for flushing toilets and watering our neighbors' horses.&lt;/p&gt;&lt;p&gt;Obviously, my power outage was just a minor inconvenience compared to the problems of billions of people faced with real disasters and perpetual water shortages. Based on research by Mekonnen and Hoekstra (&lt;span&gt;2016&lt;/span&gt;), UNICEF reports that “…four billion people—almost two thirds of the world's population—experience severe water scarcity for at least one month each year, and over two billion people live in countries where water supply is inadequate (https://www.unicef.org/wash/water-scarcity).” This experience made me contemplate the scope of groundwater science and wonder if we are emphasizing the right things in our work and ignoring the big picture while we focus on the small stuff.&lt;/p&gt;&lt;p&gt;&lt;i&gt;Groundwater's&lt;/i&gt; publisher, Wiley, lists the top four issue categories addressed by papers in the journal during the past year as, (1) groundwater flow models; (2) groundwater/aquifer recharge; (3) flow/solute transport simulation; and (4) groundwater solute composition and concentrations. These are all important and interesting topics but may not directly address one of the fundamental issues of our time—global water supply and sustainability, the topic of a rece","PeriodicalId":12866,"journal":{"name":"Groundwater","volume":"62 6","pages":"820-821"},"PeriodicalIF":2.0,"publicationDate":"2024-10-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/gwat.13451","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142515291","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Exploring Freshwater Beneath the Ocean Floor","authors":"Jeeban Panthi,&nbsp;Rachel Spinti","doi":"10.1111/gwat.13446","DOIUrl":"https://doi.org/10.1111/gwat.13446","url":null,"abstract":"","PeriodicalId":12866,"journal":{"name":"Groundwater","volume":"62 6","pages":"830-831"},"PeriodicalIF":2.0,"publicationDate":"2024-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142642427","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Integrating ERT and SP Techniques for Characterizing Aquifers and Surface-Groundwater Interactions","authors":"Md Lal Mamud,&nbsp;Robert M. Holt,&nbsp;Craig J. Hickey,&nbsp;Andrew M. O'Reilly,&nbsp;Leti T. Wodajo,&nbsp;Parsa Bakhtiari Rad,&nbsp;Md Abdus Samad","doi":"10.1111/gwat.13444","DOIUrl":"10.1111/gwat.13444","url":null,"abstract":"<p>This study enhances the understanding of riverbank filtration and improves management of the Mississippi River valley alluvial (MRVA) aquifer during a managed aquifer recharge (MAR) pilot project at Shellmound, MS. Using high-resolution electrical resistivity tomography (ERT) and self-potential (SP) geophysical methods, we characterized the heterogeneous MRVA aquifer and monitored groundwater flow near a pumping well. ERT was used to provide detailed spatial characterization, filling gaps left by airborne electromagnetic (AEM) data and soil boring logs, while SP techniques were used to monitor groundwater flow, predict drawdown trends, and investigate surface-groundwater interactions. Results showed that SP signals were influenced by groundwater flow, river infiltration, and water mixing due to pumping disturbance of natural geochemical stratification, with significant river interaction observed after 1 h of pumping. The integration of ERT and SP methods revealed lithologic heterogeneity, explaining greater drawdowns on the northern side of the well and increased flow from the riverside. This comprehensive approach offers valuable insights into aquifer management and sustainability.</p>","PeriodicalId":12866,"journal":{"name":"Groundwater","volume":"63 2","pages":"265-279"},"PeriodicalIF":2.0,"publicationDate":"2024-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142515290","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Artesian Wells of Batavia, Dutch East-Indies 1872 to 1878","authors":"Paul Whincup,&nbsp;Arjen van Schaijk","doi":"10.1111/gwat.13449","DOIUrl":"10.1111/gwat.13449","url":null,"abstract":"","PeriodicalId":12866,"journal":{"name":"Groundwater","volume":"63 1","pages":"130-136"},"PeriodicalIF":2.0,"publicationDate":"2024-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/gwat.13449","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142484115","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}