system: You are a contract-analysis assistant performing a span-extraction task. You are given an excerpt from a commercial contract and the name of a clause type to locate within it.

Return the exact text of the requested clause, copied verbatim from the excerpt — identical wording and punctuation, with no paraphrasing, summarising, explanation, or added commentary.

The excerpt is one window of a much longer contract and often will not contain the requested clause. If the requested clause does not appear in this excerpt, respond with exactly: Not found.

Output only the extracted clause text, or the exact string `Not found.` — nothing else.

user: Contract excerpt:
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shall have absolute discretion and authority to partially or totally shutdown any and all operations and activities (and temporarily or permanently discontinue the services) contemplated hereunder at any time, if in Transporter's sole discretion, such shutdown is warranted to (i) ensure the safety of persons, property, or the environment; (ii) ensure the operational integrity of the Gathering System; or (iii) modify, inspect, maintain or repair the Gathering System. Transporter shall notify Shipper in writing in the event of any of the occurrences listed above. In such cases, Transporter shall not have any liability to Shipper for such shutdowns. 3 (b) In the event interruption of service is required, Transporter's dispatcher will advise Shipper of an interruption as soon as practicable. (c) Nothing contained herein shall preclude Transporter from taking reasonable action(s) necessary to adjust receipts or deliveries hereunder in order to maintain the operational integrity of the Gathering System. 2.5 Line Fill and Tank Bottom Inventory. (a) Either prior to or after the acceptance of Crude Petroleum for transportation, Transporter will, upon reasonable notice, require Shipper to provide a pro rata part of the volume of Crude Petroleum necessary for pipeline fill, unavailable stocks below tank connections, and reasonable additional minimum quantities required for efficient operation or to safeguard Transporter's tankage during passage of a tropical storm or hurricane. Crude Petroleum provided by Shipper for this purpose may be withdrawn after reasonable written notice of Shipper's intention to discontinue shipment in the Gathering System. Transporter may require advance payment of final transportation charges and settlement of any unpaid accounts receivable before final delivery will be made. (b) In the event Shipper's inventory balance drops below its pro rata part of the volume of Crude Petroleum necessary for pipeline fill, unavailable stocks below tank connections, and reasonable additional minimum quantities required for the efficient operation of the system, then Transporter will require Shipper to provide the necessary volume to meet its pro rata part of such volume of Crude Petroleum. (c) In the event that Shipper maintains an inventory balance after Shipper ceases movements on the Gathering System or Shipper gives written notice of its intent to cease movements over the system and Shipper is unable to schedule appropriate shipments to clear the inactive inventory balance, Shipper will be required to settle the inactive inventory balance through Transporter. In the event no such Shipper notice is given, then Transporter may require either an adjustment in Shipper's inventory balance or settlement of Shipper's inventory balance at any time after Shipper has ceased making movements under this Agreement for a period of six months. Such settlement will be based upon the fair market value of the Crude Petroleum, as published by Platts, at the time Shipper provides written notice of termination of this Agreement or if no such written notice is given, then at such time as Transporter calls for the settlement of the Shipper's inventory balance. ARTICLE 3 RATES AND CHARGES 3.1 Transportation Charges. Crude Petroleum accepted for transportation by Transporter shall be subject to the transportation rates set forth on Exhibit A plus any other applicable charges specified in this Article 3. 4 ARTICLE 4 QUALITY AND PRESSURE SPECIFICATIONS 4.1 Quality Specifications. Transporter reserves the right to reject any and all shipments of: (i) Crude Petroleum delivered by Shipper to Transporter whose gravity, viscosity, and/or other characteristics are such that it is not readily susceptible to transportation through the Transporter's existing facilities and it will damage the quality of other shipments or cause disadvantage to other shippers and/or the Transporter; (ii) Crude Petroleum containing water, sediment and other impurities totaling in excess of one per cent as determined by centrifugal test, or by such other tests as may be agreed upon by the Shipper and Transporter; or (iii) Crude Petroleum where Shipper has failed to comply with all applicable laws, rules, and regulations made by any governmental authorities regarding shipment of Crude Petroleum. 4.2 Contaminants. Transporter has the right, at its discretion, to reject crude oil containing contaminants. If Transporter determines that a Shipper has delivered to Transporter's facilities Crude Petroleum that has been contaminated by the existence of and or excess amounts of impure substances, including but not limited to chlorinated and/or oxygenated hydrocarbons, arsenic, lead and/or other metals which results in harm to other shippers, Downstream Pipelines, users of the contaminated Crude Petroleum or Transporter, such Shipper will be excluded from further entry into applicable segments of the pipeline system until such time as the quality of the Crude
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Extract the exact clause related to "Minimum Commitment" from the excerpt above.

assistant: In the event Shipper's inventory balance drops below its pro rata part of the volume of Crude Petroleum necessary for pipeline fill, unavailable stocks below tank connections, and reasonable additional minimum quantities required for the efficient operation of the system, then Transporter will require Shipper to provide the necessary volume to meet its pro rata part of such volume of Crude Petroleum.