Defect and Enhancement Severities Levels Severity 1: Critical - Defects or Enhancements that cause or resolve the following: Environment or System Outage: one or more systems, or a function within a system, are rendered inaccessible or stop functioning all together (e.g. Markets UI, Outage) Environment or System Instability: one or more systems are experiencing uncontrolled data loss, memory leakage, component locking ,or similar error resulting in intermittent volatility of the system (e.g. Markets Settlements unexpectedly “dumps” all data older than seven operating days) Impacts to key Participant Milestones: a systems issue which impacts our ability to meet SPP milestone obligations to Participants (e.g. Conduct Annual TCR Auction Milestones, Onboarding dates for new Market Participants, Conduct Phase II Market Participant Testing Milestones). Business Owners, Project Managers, and/or Testing Leads should be prepared to escalate these issues to Program Leadership with the recommendation to potentially defer the external Milestone if the issue is not resolved prior to the target date Risk to meeting SAE16 or CIP Standards (e.g., logs not updating, lack of logging where expected, system monitoring failure, etc.) or Risk to meeting SPP Tariff and Protocols High Risk Vulnerabilities such as unauthorized access, revealing of data to improper Participant or external party, revealing of sensitive system information (e.g., passwords, authentication inoperable) In general, there are no options to manually mitigate (workaround) a Severity 1 Issue Severity 1 Issues are not eligible for deferral. In the event a Severity 1 Issue is deemed deferred, the severity level must be reduced.

Defect and Enhancement Severities Levels Severity 2: High - Defects or Enhancements that do not meet the Severity 1 definition that cause or resolve the following: Impair SPP’s ability to manage the reliability of the SPP footprint or perform daily operations functions Significantly impacts more than two-thirds (66%) of SPP’s participants as measured by the number of participants, or either 90% of SPP’s generational capacity or load served Result in an incorrect calculation of Participants’ financial position or the validity of an SPP Settlement Statement / Invoice (e.g., calculation of Market / Auction results, pre- Settlements Staging/POPS calculations, core Settlements calculations, data published via Statement/Invoice) Impact closing an internal SPP Test Stage: While a single Issue would likely not have such an impact, analysis of Severity 2 Defects is part of the Exit Criteria for each Stage. Business Owners, Project Managers, and Testing Leads should be prepared to escalate these Issues to Program Leadership if the probability of missing a Test Stage closure date due to one or more Severity 2 Issues becomes greater than 50%. There may be options to manually mitigate Severity 2 Issues, but generally these workarounds are likely only sustainable for a short term.

Defect and Enhancement Severities Levels Severity 3: Medium - Defects or Enhancements that do not meet the Severity 1 or Severity 2 definitions that cause or resolve the following: The impact to SPP reliability and/or markets capabilities is manageable The Issue generally impacts less than two-thirds of SPP’s Participants or less than 90% of SPP’s generational capacity or load served The Issue impacts a non-critical software component or business function The Issue is deemed to only impact rare or low priority business conditions / scenarios There should be options to manually mitigate Severity 3 Issues with the ability to sustain such workarounds with existing SPP or Participant resources The Issue should not impact closing an internal SPP Test Stage. Individual Severity 3 Issues do not require specific analysis; however, a combination of several related Severity 3 Issues may be evaluated in the Test Stage closure discussion if the overall impact of those Issues, specifically the manual mitigation options, is considered unsustainable. The benefits (improved reliability, market efficiency, reduced risk) are moderate to significant when compared to the implementation costs and time.

Defect and Enhancement Severities Levels Severity 4: Low - Defects or Enhancements that do not meet the Severity 1, Severity 2 or Severity 3 definitions that cause or resolve the following: Do not have any reliability or operations impact The item is considered cosmetic or “nice to have” and do not materially alter system functionality Impact documentation/training deliverables These Issues likely do not require a manual workaround The benefits (improved reliability, market efficiency, reduced risk) are minimal to low when compared to the implementation costs and time.