• Data Overload – Part 2

  • In my last article I discussed some of the research requirements for conducting a Phase 1 Environmental Site Assessment (ESA), in particular the use of environmental databases to confirm the history and development of a particular property, and to assist in determining potential environmental concerns that may impact the Site. One of the research tools I employ for every Phase 1 ESA I undertake is an environmental database report from Environmental Risk Information Services (ERIS).

    Common Problems with Environmental Databases
    I have observed a number of problems with environmental databases in general, and database managers like ERIS have also run into these issues; which can include:

    • Incorrectly entered original data (e.g. incorrect GIS coordinates).
    • Insufficient or inaccurate original data (e.g. incomplete provincial well records).
    • Wrong municipal address is used for the data search (e.g. Main St North vs. Main Street South).
    • Historical changes in Street names (e.g. Main Street formerly called King Street), or changes in municipal address numbering.
    • Too many databases and too much data can lead to possible data conflicts (e.g. data reported in a private database; but not in a regulatory database).
    • Missing reference data (i.e. what do certain codes signify).
    • Duplicate records, or out-of-date records that have not been updated at the source.
    • Missing Unique Identifier for records - this makes it difficult to match records and identify records.
    • Data still in paper copy or PDF which makes it difficult to extract the information.
    • Absence of relevant data for the Site does not always mean there are no records, sometime you have to double check in several databases.
    • When no data is returned for a database search or information request; nil results are still reportable.

    Data! Data! I can’t make bricks without clay!” Sir Arthur Conan Doyle

    Avoiding Database Pitfalls
    I asked Mike Chester and Carolyn Inglis of ERIS to walk me through the steps ERIS takes to confirm data and vet their information prior to plotting and reporting, and to avoid some of the problems noted above. Data is analyzed when first received by ERIS to understand the data model and to ensure all records requested have been provided from the source database. This includes confirming the accuracy and usability of the supplied coordinates, checking for missing data fields, and any available updates. All database information (particularly coordinates) is dependent on the accuracy and validity of the original data entry in the source database. Procedures and techniques such as address cleansing software, geocoding and manually reviewing data sets are employed to screen for incorrect addresses, alternate and historical street names or other potential errors. As a last step the Report Analyst looks at all records within a report to ensure all data is plotted correctly.

    “True genius resides in the capacity for evaluation of uncertain, hazardous, and conflicting information.” Winston Churchill

    A great deal of professional judgement is required to accurately assess the data and determine the reliability and relevance of the reported data with regards to the ESA property. Incorrectly interpreted data can sometimes lead to serious implications for the consultant and for ESA proponents and other stakeholders. In a future article I will discuss how you can properly interpret the data, and steps you can take to confirm the validity of your information when confusing or conflicting data is encountered.

    Bill Leedham, P. Geo., CESA, QPesa

    Bill is the Head Instructor and Course Developer for the Associated Environmental Site Assessors of Canada (www.aesac.ca); and the founder and President of Down 2 Earth Environmental Services Inc. You can contact Bill at info@down2earthenvironmental.ca