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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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 Petroleum is to the satisfaction of the Transporter. Transporter is not responsible for monitoring receipts or deliveries for contaminants. Further, Transporter reserves the right to dispose of any contaminated Crude Petroleum blocking its pipeline system. Disposal thereof may be made in any reasonable manner including but not limited to commercial sales, and any liability associated with the contamination or disposal of any Crude Petroleum shall be borne by the Shipper introducing the contaminated Crude Petroleum into Transporter's system. Shipper liability includes, but is not limited to, claims from other shippers, carriers, or users of the contaminated Crude Petroleum and the costs of any regulatory or judicial proceeding. 4.3 Periodic Samples. Transporter reserves the right to periodically sample and test the quality of the Crude Petroleum delivered by Shipper at any Receipt Point. Transporter shall be responsible for all costs attributable to such periodic sampling and testing. If at any time Shipper's Crude Petroleum triggers any of the rejection rights set forth in Section 4.1, Shipper shall pay for any tests performed thereafter to establish that such Crude Petroleum no longer triggers such provisions. 4.4 Pressure. The present maximum operating pressure at all reception points is 1440 psig. Shipper's injection pressure shall be maintained within this stated maximum limit and shall conform, as near as possible, to the hydraulic gradient. Transporter reserves the right to reduce the maximum operating pressure by written notice to Shipper. Shipper shall furnish, or cause the producer from which Crude Petroleum is purchased to furnish, install, calibrate, and maintain continuous pressure recording devices at or near injection points to monitor pipeline operating pressures. Copies of the recording charts taken from these recording devices shall be furnished to Transporter on a weekly basis by Shipper. Shipper shall also furnish Transporter copies of annual calibration certificates for recording devices. Transporter reserves the right to witness calibration of these devices, and Shipper shall notify Transporter at least 48 hours prior to the initiation of such calibration procedures. Circumstances may arise which in Transporter's judgment require the Gathering System, or any part thereof, be shut down. Following such shutdown periods, Shippers shall obtain authorization from Transporter prior to the resumption of injections. 5 4.5 Excess Water, Sediment and Other Impurities. If during any monthly accounting period, the weighted average of the BS&W on all meter tickets covering Crude Petroleum delivered to Transporter by Shipper reflects a water, sediment and other impurities content which exceeds 1%, Shipper shall pay to Transporter a handling charge as specified in the table in Exhibit A on such excess water, sediment, and other impurities to cover the treating, separation and other aspects of handling such excess water, sediment and other impurities delivered to Transporter. This explicitly excludes disposal. Transporter shall accept excess water for handling only when Shipper has made the necessary arrangements for disposal of such excess water. Shipper may dispose of its excess water by method acceptable to Transporter such as barging or trucking subject to a mutually agreed upon schedule for excess water removal by Shipper from Transporter's Grand Isle tankage. As an alternative, Shipper may request Transporter to dispose of Shipper's excess water by use of Transporter's onshore disposal wells. The fees for disposal are set forth in Exhibit A. In any event, Shipper must contact Transporter in advance at 713-351-3000 to schedule means by which BS&W will be disposed. Where no meter tickets are available or meter tickets are in Transporter's opinion unreliable, water, sediment and other impurities in the system in excess of that reported on acceptable meter tickets will be allocated in a fair and equitable manner by
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Extract the exact clause related to "Change Of Control" from the excerpt above.

assistant: Not found.