R Programmer / Data Scientist

Resume posted by fristachi

Desired position type: Freelance
Location: Santa Fe New Mexico, United States

Contact fristachi


With over 15 years experience conducting human health and ecological risk assessments and analyzing environmental data for public sector(tribal and state, federal) and private sector (gas & oil and transportation), my strong understanding of the relationships among the different facets of an environmental investigation allows me to quickly develop practical and efficient approaches to problem definition, sampling design and data analysis implemented through strong statistical computing skills in R, SQL, SAS and ArcGIS.


BS, Environmental Health Science, University of Georgia, 2000

BS, Statistics, University of Georgia, 2000

MS, Environmental Health Science/ Risk Sciences and Public Policy, Johns Hopkins University Bloomberg School of Public Health, 2004



New Mexico Department of Health, Epidemiology & Response Division, Environmental Health Epidemiology Bureau, Santa Fe, NM.  Environmental Health Epidemiologist. 2016 to present

  • Provides leadership for Environmental Public Health Tracking (EPHT) blood-lead levels indicators and nationally consistent data and measures (NCDMs) for children and adults.
  • Provides epidemiological support for biomonitoring projects for chemicals (other than lead), including project design and planning; data collection, management, analysis, interpretation, and reporting.
  • Manages the bureau’s notifiable conditions database.
  • Provides data management and epidemiological support for the drinking water quality NCDMs development, including community water system and private well datasets
  • Maintains ambient air quality indicators and measures for particulate matter and ozone
  • Develops in coordination with the New Mexico Environment Department and New Mexico Game and Fish on fish consumption advisories for New Mexico
  • Serves as a staff member on CDC Lead Content Workgroup, Drinking Water Content Workgroup, Biomonitoring and Private Wells Technical Advisory Group (TAG), for the Tracking Program. Assist with grant and report writing.

Fristachi Scientific Consulting, LLC, Los Alamos, NM. President. 2010 to 2016

Founder of a multi-disciplinary environmental consultancy providing innovative solutions for determining the nature and extent of soil and groundwater contamination, fate and transport modeling, human health and ecological risk assessment, environmental statistics, remedial alternatives evaluation and feasibility studies in support of environmental remediation and compliance monitoring activities. Projects include:

Los Alamos National Laboratory. Senior consulting risk assessor providing risk assessment and statistical support for human health and ecological assessments for the S-Site Aggregate Area Investigation Reports and Potrillo/Fence Canyon Aggregate Area Supplemental Investigation Reports.

US Department of Energy. Senior consulting risk assessor for human health and ecological assessments for chemicals and radionuclides in soil and rock via multiple scenarios, including vapor intrusion modeling at the Miamisburg, Ohio closure project.

Rocky Mountain Oilfield Testing Center (RMOTC) Provided data validation support for landfill groundwater sampling program.

Gary/Chicago International Airport. Developed a sampling plan to assess pollution on airport property and form plans for cleanup activities in support of the upcoming airport expansion project.

NuWest North Maybe Mines. Calculated bioaccumulation factors for plant tissue in support of ecological risk assessments at East Mill Dump and North and South Open pit mines. Developed a sampling plan to define the distribution of concentrations representative of background for the area and specified methods for development of site-specific background threshold values

Magnablend, Inc, Mills, WY site. Related to the presence of arsenic and selenium in soil and selenium in groundwater in excess of default criteria, developed a background sampling design that utilizes use of background soil data collected previously as part of a remedial investigation at the nearby BP/Amoco Former Refinery North Properties. BP North Properties

Lower Passaic River Study Area. Developed distributions of exposure durations for residents in the LPRSA, based on the probability of a resident moving out of the study area during a 5-year age group and the probability that a person will die during that period using U.S Census Bureau data and N.J. Department of Health (NJDH), Center for Health Statistics Bergen, Essex, Hudson and Passaic county mortality data for 2000-09.

NAVFAC Bangor. Performed a cluster analysis in support of the sampling plan for the Nearshore Functional Assessment Tool calibration area in Puget Sound. A total of 4770 potential sampling locations were selected based on 14 Biology, 14 engineering and 29 hydrological clustering variables. And were analyzed using a Gaussian finite mixture EEE model.

FE Warren AFB Landfill-C501/Landfill 8 long‐term monitoring: The goals of the assessment were to determine the presence of any statistically significant concentration increases (SSI) for any analyzed constituents and statistically evaluate inter-well and intra-well concentrations to characterize concentration plume fate and transport and evaluate the potential for an SSI using a non-parametric prediction limit statistical test for future median.


New Mexico Environment Department, Air Quality Bureau, Santa, Fe, NM, Enforcement Specialist. 2014 to 2015

Resolved areas of noncompliance with air quality regulations and permit conditions through reviewing inspection reports, affirming areas of concern, drafting notices of violation, developing corrective actions, evaluating corrective action verifications and participating in settlement discussions for assigned cases.

Battelle, Statistics and Information Analysis Product Line, Columbus, OH. Research Scientist. 2007 to 2009

Senior risk assessor for the dose- response modeling effort and calculation of benchmark dose values for numerous chemicals identified by USEPA in the Integrated Risk Information System (IRIS) program. Critically evaluated data from key mammalian and human toxicology studies for the development and modeling of benchmark dose values for the endpoint(s) of concern along with quantification of any uncertainties.

Developed R scripts to parse data into a Department of Homeland Security Biological Threat Risk Assessment (BTRA) model that estimated the risks associated with the intentional release of 26 biological agents and the parameters associated with incubation time, treatment availability and human behavior with the intention of prioritizing countermeasures.

Technical leader for development of a statistical methodology for calculating estimates and bootstrap confidence intervals based on the multistage cancer model for trichloroethene using data from pharmacokinetic (PBPK) Bioassay model Data. Collaborating with toxicologists, mathematicians and programmers, algorithms and scripts in R were written to calculate bootstrap confidence intervals from the output of multistage polynomial cancer model written in C++.

Employed mixed model analyses using SAS to test the stability of disinfectant by-products (DBPs) mixtures in treated drinking water used for rodent bioassays resulting in presentations at national toxicology conferences. [09/2007-09/2009]

U.S. Environmental Protection Agency, National Center for Environmental Assessment, Cincinnati, OH. Environmental Health Scientist/ORISE Fellow. 2004 to 2007

Conducted quantitative analyses of environmental exposure data, with an emphasis on chemical mixtures, including exposure modeling, linear regression modeling, uncertainty analysis, descriptive statistics, and the compilation and analysis of large datasets. Prepared work plans; reviewed toxicological and human exposure data; data management; data interpretation; model development; preparation of studies reports.

Principal investigator for probabilistic exposure assessments of several contaminants typically found in treated drinking water or source water, including mixtures of organotins, nitrosamines, cyanobacterial toxins and drinking water disinfection byproducts for use in developing drinking water regulatory guidelines. Published four journal publications (three as first author), a book chapter and contributed to an important EPA report on cumulative risk assessment. The work on organotins and nitrosamines a have become important to the US Environmental Protection Agency for use in developing drinking water regulatory guidelines

U.S. Environmental Protection Agency, Office of Science Coordination and Policy, Washington, DC. Graduate Student Researcher. 2003 to 2004

Researched endocrine disruption-related health effects from exposure to metals, ultimately focusing on the effects of cadmium on measures of skeletal health using NHANES data. Provided statistical support for studies on the spatial distribution of dietary intake of mercury via fish and shellfish in the US using spatial statistical methods and geographic information systems.

State of Georgia Department of Natural Resources, Environmental Protection Division, Athens, GA. Environmental Data Analyst.

Developed a relational database using Microsoft Access to analyze toxicological data on levels of metals, PCBs, dioxins, and pesticides in edible fish tissue collected from 1991 to 2001 in support of the Fish Consumption Advisory program. Developed queries and produced maps with ArcView and developed shapefile-based directories linked to geodatabases anchored in the Access database.


  • R
  • SAS
  • Matlab
  • Stata
  • SQL
  • Microsoft Excel and Access
  • Statistics
  • Probabilistic analysis
  • Mixed models
  • Survey data analysis
  • Time series modeling
  • Uncertainty/sensitivity analysis
  • Critical evaluation of toxicology studies; Dose-response modeling; Environmental Exposure modeling
  • Fate and transport modeling
  • Risk assessment