People in the UCSC Hydrogeology Research Group

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This is a partial list of folks who have been involved in some way with the UCSC Hydrogeology group. Please let me know if I left anyone out!


grad students


Would you like me to write you a letter of recommendation? Please read and follow these instructions carefully!

Postdoctoral Researchers

Tess Weathers (2016-18), Ph.D. from Colorado School of Mines, worked on marine hydrogeology, coupled modeling, geothermal field studies, and coupled hydrologic-biogeochemical-microbial processes during groundwater recharge. Dr. Weathers is now on the faculty of Chabot College.

Rachel Lauer (2013-16), Ph.D. from Pennsylvania State University, worked on marine hydrogeology, coupled modeling, geothermal field studies, and geotechnical characteristics of sediments from seepage areas. This postdoc was funded through the Center for Dark Energy Biosphere Investigations. Dr. Lauer is now on the faculty of the University of Calgary.

Jared Kluesner (2014), worked with me briefly in Winter 2014 on a seismic reflection processing project, soon after finishing a longer postdoc with Eli Silver. Dr. Kluesner now works for the U. S. Geological Survey in Santa Cruz.

Abdellah Cherkaoui (2000-02), Ph. D. from University of Washington (2000), participated in RetroFlux (2000) and first TicoFlux (2001) expeditions, crafted graphically-driven software for processing heat flow data using MATLAB. Dr. Cherkaooui works for Volta Charging in San Francisco.

Philip Stauffer (1999), Ph. D. from UCSC (with B. Bekins and C. Moore), worked with extensively with FEHM to model heat-fluids-solutes-gas transport in a range of hydrogeologic environments, modified the UCSC version of the code to handle a broader P-T range than the stock code, made other improvements, now on staff at Los Alamos National Laboratory, NM.

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Graduate Student Researchers

I am NOT recruiting graduate students for the 2020-21 admissions cycle.

Please read about recent and ongoing research activities here, and contact me for more information.

Current students: Galen Gorski (Ph.D. candidate), Araceli Serrano (Ph.D. student), Adam Price (Ph.D. student), Jenny Pensky (Ph.D. student). ...more info to be added soon...

E. Teo (M.S., 2019), BA in History (Applied Mathematics minor) from NJ Tech, MS in Sustainability Science from Montclair State University, research at UCSC involved developing a GIS-based assessment of suitability for managed recharge.

Sarah Beganskas (PhD, 2018), BS from Amherst College, worked on managed aquifer recharge, vadose zone processes and modeling, real-time environmental sensor networks. NSF Graduate Fellow! Dr. Beganskas took a Postdoctoral position at Temple University.

Kyle Young (MS, 2017), BS in Mechanical Engineering from the U.S. Coast Guard Academy, completed a rigorous set of courses in physics, mathematics, and earth sciences, and a research project on runoff and groundwater recharge, in preparation for teaching at the U.S. Coast Guard Academy. He is now on the faculty of the CGA.

Dustin Winslow (PhD, 2015), BS from UC Berkeley in Astrophysics, joined hydrogeology group to do marine hydrogeology research. NSF Graduate Fellow! Published first first three-dimensional models of an outcrop-to-outcrop hydrothermal siphon. Dr. Winslow took a position in data science with GrowthIntel in London, UK, and has since moved to Citymapper, also in London.

Bruce Daniels (PhD, 2015), BS from MIT in Computer Engineering, worked on models of precipitation and impacts on surface water and groundwater conditions under conditions of climate change. Dr. Daniels is applying his expertise as President of the Board of Directors of the Soquel Creek Water District.

Alanna Lecher (PhD, 2015 co-supervised with Adina Paytan), BS from USF, studied submarine groundwater discharge, nutrient cycling, and methane destabilization. Dr. Lecher is a member of the faculty with Lynn University in Boca Raton, FL.

Andrew Racz (MS, 2014), two BS degrees from Lehigh University in Civil and Environmental Engineering and Earth and Environmental Science, UCSC STEPS Fellow, thesis on the physics of managed aquifer recharge. Andrew is a Professional Engineer with Marina Coast Water District.

Priya Ganguli (PhD 2013, co-supervised with Russ Flegal and Peter Swarzenski - USGS), BS from Indiana University, MS from UCSC, explored mercury speciation and fate in association with submarine groundwater discharge. She was a postdoc at WHOI, now a faculty member at Cal State Northridge.

Tess Russo (PhD, 2012), BS from Tufts University in Mechanical Engineering, and considerable additional coursework from Portland State University in Environmental Science, interested in surface water - groundwater interactions, managed recharge, riparian wetlands, and extreme precipitation. NSF Graduate Fellow. Tess finished in Summer 2012, took a Postdoc with the Earth Institute at Columbia University, to study managed recharge in northern India. She then became a faculty member at Pennsylvania State Univeristy, before decamping for Denmark where she works as a research scientist for Global Good.

Calla Schmidt (PhD, 2011), BS from University of Oregon, Keck Fellow studied seismology with folks at UO and U Washington, interested in surface water - groundwater interactions and influence of managed aquifer recharge on water supply and quality. EPA-STAR Graduate Fellow! Sea Grant Delta Science post-doc with USGS, Menlo Park, CA and UCSC through calendar 2012, then joined the faculty of the University of San Francisco.

Robert Sigler (MS, 2007), BS from the Ohio State University, focusing on dynamics and geochemistry of surface water - groundwater interactions. Lab and field technician at CSUMB.

Christine Hatch (PhD, 2007), BA from Amherst College, joined UCSC Hydrogeology group after a few years of consulting, working on surface water - groundwater interactions with an emphasis on thermal methods, also worked at the USGS. Post-doc at UNR with Scott Tyler, now Assistant Professor at University of Massachusetts, Amherst.

Mike Hutnak (PhD 2007), BS from U Washington, worked for several years as a seagoing marine technician, built numerous oceanographic and lab instruments, research on marine hydrogeology, field work and numerical modeling, JOI/USSAC graduate fellow and IGPP Young Fellow. Post-doc at USGS with Shaul Hurwitz and Steve Ingebritsen, now runs his own hydrogeologic consulting company (RightOnQ) in Santa Cruz, CA.

Greg Stemler (coursework MS, 2005), BS from UCSC, research project focused on geology of the Pajaro Valley and maintenance, calibration and functioning of the Corralitos Creek and Pajaro River stream gauge network, now working for AMEC-Geomatrix in Oakland, CA.

Chris Ruehl (MS, 2004), BS in Chemical Engineering from Rice, worked on biogeochemical cycling and surface water - groundwater interactions. NSF graduate fellow, worked with P. Chuang (UCSC) on Ph. D. in atmospheric chemistry, post-doc at UC Davis then UC Berkeley. Now works for California Air Resources Board.

Patrice Friedmann (MS, 2003) - after completing BS in Earth Sciences (Highest Honors in the major!), stayed around for a 5th year MS through Ocean Sciences, co-advised by C. Geoff Wheat (U Alaska) and Peggy Delaney (Ocean Sciences). Patrice's thesis was on seafloor hydrothermal seepage offshore of the Nicoya Peninsula, near the Middle America Trench, Costa Rica.

Glenn Spinelli (PhD, 2002), - BS from Penn State, researched groundwater/estuarine interactions and sediment transport and geotechnical properties in Spring 2002, field work, lab work and modeling, faculty at New Mexico Tech.

Jonathan Cook (MS, 2002), primary advisor: Slawek Tulaczyk, studied landsliding in the Holister Hills area, has taught courses in UCSC Earth Sciences.

Nicole Beck (PhD, 2001), BS and MS from UCSC (Earth Sciences and ETOX), primary PhD advisor: Ken Bruland, researched biogechemical cycling and the physical and chemical dynamics of estuaries, principal at 2nd Nature.

Emily Giambalvo (PhD, 2001), BA, Amherst, PhD research on seafloor hydrogeology and reactive transport, involving laboratory and field measurements and numerical modeling, NSF graduate fellow. Currently staff (on leave) from Sandia National Laboratory.

Joshua Stein (PhD, 2000), B. A. Middlebury, MS Wesleyan, researched seafloor hydrogeology at the ridge crest and on ridge flanks, field measurements and numerical modeling. Currently on staff at Sandia National Laboratory.

Jonathan Lear (MS by coursework, 2000), BS UCSC, emphasized organic chemistry and field methods for his coursework MS, Hydrologist with the Pajaro Valley Water Management Agency in Watsonville, CA; now consultant with Balance Hydrologics.

Danielle Widemann (MS by coursework, 2000), working as a geology instructor at Solano Community College.

Demian Saffer (PhD, 1999), defended his PhD (primary advisors: Casey Moore and Barb Bekins, USGS) on coupled flows in accretionary systems, NSF fellow, took a post-doc at the USGS with Bekins and Steve Ingebritsen, became a faculty member at University of Wyoming, moved to Penn State a few years later.

Jon Erskine (MS, 1998), BS Occidental College, worked in consulting for a few years, based on his MS research on hydrogeology, geostatistics and sea level change in southern Monterey Bay. Worked for several years at Geomatrix, Inc. in Oakland, CA, then Senior Hydrogeologist with Northgate Environmental Management, Inc. Now Senior Geologist with Graniterock.

Deb Underwood (MS, 1998), primary advisor: Eli Silver, based on her research on shallow seismic stratigraphy, hydrogeology, and sea level change in southern Monterey Bay, now working at Geometrics, in Colorado.

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Undergraduate Student Researchers

Ryan Harmon (BS student), senior thesis on GIS analysis of MAR suitability and runoff

Eric Lujan (BS student), senior thesis on sediment texture in a stormwater capture and MAR system

Tyler Sproule (BS student), senior thesis on calibration and use of autonomous thermal instrumentation

Emily Edwards (BS 2013), senior thesis on infiltration testing of a potential managed recharge site

Barbara Taylor (BS 2013), senior thesis on managed recharge through stormwater capture

Amalia Slovacek (BS 2012), senior thesis on marine hydrogeology

Christina Richardson (BA, 2011), research internship in Environmental Studies on water quality

Katie Earp (BS, 2011), senior thesis on surface water - groundwater interactions

Susanna Bird (BS, 2011), senior thesis in Environmental Chemistry on water quality during MAR

Devin Stewart (BS, 2011), undergraduate researcher on MAR and soil characterization

Richard Ednie (BS, 2010) senior thesis on soil texture and MAR

Joanna Hoffman (BS, 2010), undergraduate researcher on water quality during MAR

Nicolas Massetani (BS, 2010), undergraduate researcher on MAR and soil characterization

Jared Mednick (BS, 2008), capstone in Electrical Engineering on instrumentation for using heat as a tracer of groundwater recharge

Chung Lem (BS, 2008), capstone in Electrical Engineering on instrumentation for using heat as a tracer of groundwater recharge

Rosie Saldana (BS, 2008), capstone in Computer Engineering on instrumentation for using heat as a tracer of groundwater recharge

Mark Esguerra (BS, 2008), capstone in Computer Engineering on instrumentation for using heat as a tracer of groundwater recharge

Juan Golzales (BS, 2008), capstone in Electrical Engineering on instrumentation for using heat as a tracer of groundwater recharge

Andrew Rich (BS, 2007), senior thesis on stream seepage.

Jennifer Loeffler (BS, 2007), senior thesis on stream and groundwater geochemistry.

Guttierez, Maria (BS, 2007), CAMP research project on surface water - groundwater interactions and nutrient cycling.

Iris DeSerio (BS, 2005), double major in Earth Science and Environmental Studies. senior thesis on stream and groundwater geochemistry.

Andrew Shriver (BS, 2005), senior thesis on stream seepage.

Brian Spear (BS, 2005), senior thesis calibrating deep sea temperature measurement and logging tools.

Brett Walker (BS 2004), senior thesis on geochemistry and age of ridge-flank hydrothermal fluids (co-supervised by M. McCarthy, Ocean Sciences)

Nicole Alkov (BS, 2004), senior thesis on sediment properties above a hydrothermal seepage zone, NSF-REU scholar.

Laura Roll (BS, 2004), senior thesis on stream chemistry.

Bob MacKnight (BS, 2004), senior thesis on thermal state of the upper lithosphere, offshore of Nicoya Peninsula, Costa Rica. NSF-REU scholar, worked with Eli Silver on MS on remote sensing.

Emily Underwood (BS, 2003), senior thesis on stream seepage.

Bowen Jenkins-Warrick (BS, 2003), senior thesis on stream chemistry.

Gerhart Epke (BS, 2003), senior thesis on stream seepage.

Brian Hernandez (BS, 2002), research on physical properties of marine sediments, NSF-REU scholar.

Remy Nelson (BS, 2002), senior thesis on stream seepage.

Robert Cleary (BS, 2002), senior thesis work on seafloor hydrothermal systems (NSF-REU scholar).

Patrice Friedmann (BS, 2002), senior thesis on sediment geochemistry offshore of the Nicoya Peninsula, Costa Rica, co-supervised by Geoff Wheat, NSF-REU scholar, highest honors in the major.

Raanan Badzin (BS, 2002) senior thesis in plate flexure associated with subduction offshore of the Nicoya Peninsula, Costa Rica, NSF-REU scholar, stayed at UCSC for MS with Eli Silver.

Day Frostensen (BS, 2001), senior thesis on sediment thermal conductivity.

Jenni Taylor (BS, 2000), double BA/BS in Environmental Studies and Earth Sciences, including senior thesis (Honors!) on base flow conditions in coastal California streams. Co-supervised by Brent Haddad, Environmental Studies.

Naomi Marks (BS, 2000), senior thesis on the geotechnical properties of sediments from the Mariana Forearc, and implications for a possible diapiric origin, worked in biotech for a while, went back to grad school.

Amanda Gorman (BS, 2000), senior thesis on comparison of velocity-area and tracer discharge methods for assessing groundwater seepage into and out of streams.

Carrie Graham (BS, 2000), conducted senior thesis research on base flow measurements and variations on Soquel Creek.

Brian Magee (BS, 2000), senior thesis on sediment provonance within reef systems offshore Molokai.

Lisa Darty (BS 1998), completed senior thesis on the magnetic properties and sediment fabric of materials from a hydrothermal upflow, graduated with honors.

Instructions for Those Who Would Like Me to Write Letters of RecommendationHot!

Last updated: 13-Jul-2020
Link to a PDF file containing these instructions.

So you have decided to apply to graduate school or need a letter of recommendation for a job. Good for you! I would like to do anything I can to help. But in order for me to write you a letter or provide a phone recommendation that will actually help you, you need to plan ahead and do some additional preparation. Before we get to specific instructions, please consider the following:

* Letter writers should have something constructive to say beyond observing that you are capable of following instructions or completing assignments on time. Virtually all letters of recommendation are positive, so a generically positive letter will not help you (and faint praise might even be considered to be negative). If you did not do very well in one or more of my classes, please consider carefully whether or not you want me to write a letter of recommendation. I will do my best to emphasize your talents and achievements, but I have to be honest when asked to compare you to other students, assess your readiness for graduate-level work, and discuss your ability to find novel solutions to difficult problems. I am also likely to be asked to comment on weaknesses.

* The strongest letters for admission to a graduate program generally will be from faculty, not from professional supervisors. This is because faculty know what words and phrases other faculty want to hear about prospective graduate students. Hopefully, you made a point of doing well in courses taught by faculty who can comment on your determination, creativity, maturity, and technical acumen.

* I and other faculty who may write your letters of recommendation are likely to be very busy, particularly during the time when your letters are due. In order for us to write positive letters and get them submitted on time, you need to plan ahead, provide clear and concise instructions, and follow up to make sure that the process moves smoothly.

With the above in mind, here are some guidelines and instructions, including information on timing. If you are not prepared to follow the guidelines and schedule below, please don't ask me for a letter of recommendation. When you contact me asking for letters, you will be asked to confirm that you have read the guidelines below and are prepared them. Please take your time to read this information carefully. This information (or something close to it) is likely to apply to other letter writers as well.

The information below is focused on applications to graduate school, but many of the concepts also apply to applications for professional employment.

(1) When you contact me to ask me for a letter or letters of recommendation, please tell me your full name (remind me of your last name when you were a student if it has changed), which class(es) you took with me, quarter and year when you were enrolled in my class(es), and when you graduated from UCSC. Applications for graduate school are generally due in late December to early February. You should begin talking to me and other potential recommenders no later than October or early November in order to assess who will be available to write the most positive letters. It would be much better if you checked in during the spring or summer before letters are due, so that you can plan your schedule accordingly.


* If you want to talk to me about what schools to apply to, please suggest several days/times when we might speak in person or by phone, or show up during regular office hours. This will be a conversation, not a list of programs in response to an email. This conversation will be most useful if we have it 3+ months ahead of the date when you ask me for letters of recommendation, so you have a chance to do some research, consider your academic and career goals, make initial contacts by email and phone, etc.

* Please do some preparation before you contact me. Look into several potential graduate programs, find out about entrance requirements, which faculty are doing what kind of research, coursework requirements, TA opportunities, etc. You should have some ideas about what kind(s) of program you might be looking for. Your approach should be simultaneously ambitious and realistic. For example, if you plan to apply to an engineering program, you should have taken (or plan to take) additional math, physics, programming or other technical courses, as engineering programs will expect. Be ready to talk about this with me and in preparing your application(s). Think about whether you want a M.S. or a Ph.D., whether you want a "science" program or a "studies" program, etc.

* If you want to list me as a reference on a job application, please give me an updated CV/resume, and tell me about each job to which you are applying so that I am not surprised by getting a phone call from someone in Human Resources.

(2) If you have been out of school for some time, you should tell me what you have been doing since you were enrolled as a student. In general, your application will be stronger if what you have been doing since graduation includes some technically and/or academically challenging work or studies. Please don't just send me a resume - please tell me what skills or expertise you have acquired that have helped you to prepare for graduate or professional work. Many former students stay in touch with prospective recommenders - a brief note once a year goes a long way towards demonstrating focus and a goal orientation, and it gives us something to talk about in letters that can be helpful in showing your commitment, determination, and ability to plan ahead.

(3) Once you have narrowed your list of schools (probably 4 to 8, 5-6 is common), you are ready to send a detailed request for letters of recommendation. At this point, I will have already agreed to write your letters (see step 1 above), and the next step is to provide information I'll need to get your letters written and submitted on time to the right programs. Please send me a neatly written list of programs for which letters are required. For each program, please indicate: (a) full name of school, (b) full name of program (department, school, etc) and degree desired, (c) names of any faculty or other potential sponsors with whom you have corresponded or spoken, (d) date when your complete application is due, (e) date when my letter should be received, (f) explanation as to whether my letter will be submitted electronically or as hard copy, (g) complete address for each institution (even if electronic letter/form is to be used, as I'll need to put the address on letterhead). You should provide this information at least four (4) weeks in advance of your letter submission deadline(s).


* Send all of the above in a single email, either as text or as a single attachment. Please don't make me slog through multiple emails to find all of your materials. Also, please name any files you send as attachments in a way that makes them readily identifiable. A file called, "Letters.pdf" is not much help. Better to name the file, "LastName_RecLetterInfo_YYMMDD.pdf."

* I will be preparing a custom letter for each institution, sent directly from me, so please don't ask me to send you a single letter that you can use for all applications. Generic letters are virtually worthless, as are letters that originate with the applicant.

* I don't need stamped envelopes for hard copy letters; just be sure to provide the complete mailing address, including name of person to whom letter should be directed, if any.

* Some institutions have a hard copy form that must be completed, so be sure to provide this if necessary. Others want letters on letterhead with answers to specific questions. Make sure I know about what questions should be addressed.

(4) I will be able to write better letters if you give me copies of your (draft) application materials. Ideally these will be attached to the email discussed in step (3), but you could also follow up with a (single) additonal email/letter contining this information. Your draft application will help me to focus my letter, using words that connect your achievements and goals to the specific programs to which you are applying. One draft application will usually be sufficient, unless you are applying to widely varying programs (e.g., M.S. in Hydrology and Ph.D. in Ecology). You can send me a resume if you think I need to see it to write a proper letter, but I really should have a look at your draft application. You can send me other documents as well, as you wish, but please avoid sending multi-megabyte attachments unless there is a very good reason. You should provide this information at least three (3) weeks in advance of your letter submission deadline(s).


* Unless I have a lot of lead time and am unusually unobligated, I am not likely to be able to comment on your application (edit, provide suggestions). Of course, the more I know about you prior to receiving your request (e.g., as a lab assistant, having had you in multiple classes, you being a frequent visitor during office hours, etc.), the more likely I am to find time to comment on your application essays. But you can always ask.

(5) Many institutions that use electronic submission systems will send an email prompt to your recommenders. However, this prompt will not be sent out in some cases until your application is complete, or until you reach a point in the application process where recommendation letters are requeseted (e.g., might require that you upload draft application materials). This can create a problem for your letter writers if you attempt to submit your applicaiton at the last minute and need your recommenders to follow up immediately with their letters. Many faculty set aside blocks of time, perhaps 1-2 times per week, for preparation of letters of recommendation and other administrative tasks. If your application is submitted at the last minute, sparking an electronic request for a letter of recommendation for which there is little time available, there is a good chance that I and your other recommenders will not submit your letters in time. This can result in rejection of your application! You may not worry about meeting the application deadline at the last minute, but I may be trying to prepare many other letters (I did >60 in the last round of applications) and have other deadlines that require my immediate attention. Because application deadlines often occur close to AGU, near the end of the Fall quarter, close to the winter vacation period, and/or near the start of Winter quarter, there is the real possibility that I may be unable to meet your deadline even if you warn me well in advance. In order to avoid a scheduling problem, I should receive the electronic prompt to submit your letters (having already received all other information needed to do so) at least two (2) weeks in advance of the letter submission deadline. In fact, it would be better if I had the prompt and all necessary information three (3) or four (4) weeks in advance, particularly if this occurs over the holiday break.

(6) Please follow up by reminding me, perhaps 3-4 days ahead of each deadline for letter submission, that a letter is due. I don't mind being reminded. I generally put letters of recommendation on my calendar/to-do list, with several days of buffer in case I run into scheduling problems. But sometimes I forget or there is confusion about dates. For electronic submission of letters, you should receive confirmation when my letter is submitted.


* There may be a good reason why you need to request an "emergency" letter with just a few days notice. Being unprepared until the last minute is not a good reason. You can ask for a rapid letter, but I may be unable to comply, and you might get a nasty-gram in response.

If, after reading all of the above, you would like me to write you a letter of recommendation (or several), please get to work identifying programs of potential interest and make your initial request to me, step (1) in the list above.

Please include this phrase in your email to me requesting letters:

"I have read the information on letters of recommendation at your web site and will follow the instructions carefully, paying particular attention to providing complete information in a timely way."

A final note: You are not asking for a "favor" when you request a letter of recommendation. Writing these letters is part of my job, and I get genuine pleasure in helping former students to find the right graduate program or get going with their careers.

I'm looking forward to helping you to achieve your academic and professional goals. Please be sure to let me know how it all works out!

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this page last updated: 13-Jul-2020