Section 20.25.228. Production measurement equipment for custody transfer.

	(a)  Hydrocarbon production must be measured in accordance with this section before severance from the property or unit where produced. Crude oil sample collection, handling, and analysis in connection with production measurement must be performed in conformance with relevant parts of the API Manual of Petroleum Measurement Standards, as revised as of November 30, 1998.  
	(b)  Hydrocarbon measurement equipment must be fabricated, installed, and maintained in conformance with relevant parts of the API Manual of Petroleum Measurement Standards, as revised as of November 30, 1998. Before installing or altering hydrocarbon measurement equipment used for custody transfer purposes, the operator shall submit to the commission information demonstrating conformance and obtain commission approval of the proposed installation or alteration and the methodology proposed for determining hydrocarbon volumes. The submitted information must include sample calculations, with the underlying measured data, generated using the proposed methodology. The operator may not change an approved methodology without commission approval.  
	(c)  If a totalizer system is microprocessor-based, it must be equipped with  
		(1) a backup battery or uninterruptible power supply that provides for operation during times of system power failures; or  
		(2) a backup pulse accumulator or other approved equivalent that counts and preserves meter pulses in the event of a power or computer failure.  
	(d)  If a microprocessor totalizing system is used, the reports of net measured volumes for the custody transfer intervals must, at a minimum, show the raw or factored pulses, average temperature, pressure, relative density or gravity, meter factors, correction factors, and gross standard volumes.  
	(e)  Fluid samplers must be a probe or a slipstream type. The sampler location must be located in conformance with Chapter 8 of the API Manual of Petroleum Measurement Standards, as revised as of November 30, 1998.  
	(f)  Functional bypasses may not be connected around custody transfer or sales measurement equipment such as tanks, meters, gauges, sample containers, or gas meter runs.  
	(g)  Oil meters must be periodically proved and gas meters must be periodically calibrated in conformance with relevant parts of the API Manual of Petroleum Measurement Standards, as revised as of November 30, 1998, and on a schedule approved by the commission according to the volumes being metered and the need to quickly detect inaccuracies. In metering operations, the actual throughput or gross standard volume must be determined by multiplying the indicated volume, corrected for temperature and pressure, by the meter factor obtained during proving. If a meter factor differs by more than 0.0025 from the previously obtained meter factor, from the applicable value on the meter curve, or from a baseline factor in the absence of a meter curve, the meter must be taken out of service or corrective action performed to bring the meter factor within the required tolerance.  
	(h)  Provers used for certification of custody transfer meters must be calibrated by the waterdraw method, master meter method, or other commission-approved equivalent, in conformance with relevant parts of the API Manual of Petroleum Measurement Standards, as revised as of November 30, 1998.  
	(i)  The commission will, in its discretion, require at least 24 hours notice before the following operations so that a representative of the commission can witness the operation:  
		(1) calibration of provers used for certification of custody transfer meters;  
		(2) crude oil sample collection, handling, and analysis in connection with production measurement;  
		(3) oil meter proving and volume calculations;  
		(4) gas meter calibration and volume calculations.  
	(j)  Upon request, the commission will, in its discretion, approve a variance from the requirements of this section if the variance will result in equal or improved accuracy in measuring hydrocarbons severed from the property or unit.  
	(k)  In this section, "relevant parts of the API Manual of Petroleum Measurement Standards" means the API Manual of Petroleum Measurement Standards excluding Chapter 19 in its entirety and excluding those portions of Chapter 11 other than Chapter 11.1, Volume 1; Chapter 11.1, Volume X; Chapter 11.2.1; Chapter 11.2.2; Addendum to Section 2.2; and Chapter 11.2.3. The relevant parts of the API Manual of Petroleum Measurement Standards, as revised as of November 30, 1998, are adopted by reference.  

Authorities

31.05.030

Notes

Reference

15 AAC 55.213
20 AAC 25.245

Authority

AS 31.05.030 Editor's note: A copy of the relevant parts of the API Manual of Petroleum Measurement Standards may be reviewed during business hours at the commission's office and may be obtained from the American Petroleum Institute, Order Desk, 1220 L Street, N.W., Washington, D.C. 20005-4070.

History

Eff. 4/2/86, Register 97; am 11/7/99, Register 152; am 10/18/2009, Register 192