Investigation-Procedure

 

1. Routine Investigations
   Routine investigations will be initiated when:
1. Any affected RA reports the lack of a timely/clear response from the implementing RA, or
2. TLR Level 5 is initiated.
2. Requested Investigations
Requested investigations will be initiated:
1. For any single TLR event, when requested by three entities (CA, PSE, RA, TP),
2. For TLR events recurring on the same flowgate and requested by three entities, not necessarily from the same TLR event, or
3. When the Reliability Authority did not receive the relief expected and requests an investigation.

Requests for investigation must be received within 30 days of the TLR event.

1. When TLR 3 or higher is called three times or more, within a seven-day period, on the same flowgate, or
2. When TLR 2 is called six times or more, within a 30-day period, on the same flowgate, or
3. For any reason, as deemed by the Operating Reliability Subcommittee (ORS) Chair, the Reliability Authority Working Group Chair (RAWG), or NERC director of Compliance.

• Description of purpose or cause of hold/curtailment;
• Facility or flowgate limitations and flows at the time the TLR was initiated;
• TLR levels, timing, and relief requested amounts;
• Transmission and generation outages or changes from prediction that may have contributed;
• Procedures implemented prior to hold/curtailment;
• List of known transactions not in the IDC with Transaction Contribution Factors greater than the curtailment threshold and actions taken to curtail such transactions;
• Excerpts from the RA Operations Log containing information relevant to the TLR event;
• Flowgate limitations as identified by security analysis processes conducted by the Reliability Authority for the day prior to the TLR event;
• State Estimator snapshots and security analysis, including any contingency analysis or stability analysis, along with any other recorded data indicating need for TLR;
• ATC limitations before, during, and after the TLR event;
• Description of actions taken to avoid future hold/curtailments;
• Provide IDC-generated Congestion Management Reports showing transaction curtailment list and Control Area NNL (network and native load) curtailment responsibility; and
• Redispatch actions taken.

The initial investigation shall compare all transaction curtailment lists as generated by the IDC with the list of transactions flowing as determined by the IDC (Whole Transaction Lists) both before and after curtailment. The reasons for any transactions that were excluded from curtailment shall be provided. For those transactions not curtailed, the Reliability Authority will identify those entities and any affiliation with said entities.

1. Posting of the initial investigation report, or
2. Completion of the detailed investigation report, if requested.

Once the initial investigation has been completed, it may be necessary to complete a more detailed audit of the TLR event. This would come at the request of the NERC director of Compliance, the original parties who requested the audit, the NERC ORS or RAWG Chairs, or the NERC Operating Committee Chair. Any such request must be made within 30 days subsequent to the posting of the report resulting from the initial investigation. The purpose of this investigation will be to review in detail all aspects of the TLR process from beginning to end. A team comprised of one person from compliance staff of an unaffected Region, one unaffected Reliability Authority, and one person from NERC compliance staff will carry out this detailed investigation. Additionally, at the request of the Operating Committee Chair, it may be necessary to secure the services of an independent auditor to carry out such an investigation. Such a complete investigation will require significant resources and time to complete. In such an investigation, it is not the intent to collect the same information as included in the initial report. There may be a need for additional data and information, as well as a site visit. However, all aspects of the initial report will be reviewed. Additionally, staff members will:  

• Review the stated purpose or cause of hold/curtailment and the validity of purpose;
• Review facility/flowgate limitations for accuracy and actual flows;
• Investigate the system topology model utilized and compare to the actual system topology for accuracy;
• Review SDX data and actual outages to determine if all relevant outages were submitted in order to produce accurate IDC results;
• Review other options or procedures considered and any others that may have been available before or during to avoid hold/curtailment;
• Check Reliability Authority Operational Logs for the period for consistency with stated actions;
• Review previous day system studies and any current day system studies for accuracy with known outages, limitations, generation patterns, and load expectations;
• Review any state estimator output, loading trends, etc., to determine if earlier corrective action was warranted;
• Review Transaction Curtailment Lists generated by the IDC for accuracy of the data and the calculations performed;
• Survey Control Areas for the actual time of curtailment of transactions and compare to Reliability Authority requests;
• Review whole transaction lists from the IDC both before and after curtailment and compare to curtailment list. Also, determine if new transactions were initiated in restricted directions;
• Collect actual schedules from sink Control Areas and compare to whole transaction lists from the IDC to determine if all schedules were entered and, hence, subject to curtailment;
• Review transaction list from the IDC indicating upcoming higher priority transactions and actions taken to adjust current schedules;
• Review RAIS system messages for consistency and other methods of communication;
• Review TLR levels, timing, and relief-requested amounts;
• Review ATC limitations before, during, and after the TLR event and OASIS reservations related to the flowgate;
• Review and analyze actions taken to avoid future hold/curtailments for expected effectiveness; and 
• Identify of any NERC policies violated.

1. Review of the initial report and identification of key issues to be investigated;
2. Identification of additional information required (This should be completed as quickly as possible to allow reasonable time for the parties involved to respond and to include the data in the report.);
3. Collection of additional data and information (Reliability Authorities and other parties are to provide items requested within 10 business days of the request.);
4. Initial review and findings developed by the review team;
5. Review of findings of fact with Reliability Authority who initiated the TLR;
6. Development of findings and recommendation of the investigation;
7. Development and submission of final report;
8. Appeals by the affected Reliability Authority (if in disagreement with findings); and  
9. Possible dispute resolution.