COMMITMENTS AND CONTINGENCIES

We are involved in legal, tax, and regulatory proceedings before various courts, regulatory commissions, authorities, and governmental agencies with respect to matters that arise in the ordinary course of business, some of which involve substantial amounts of money. We believe that the final disposition of these proceedings, except as otherwise disclosed in these notes to our financial statements, will not have a material adverse effect on our results of operations, financial position, or liquidity.

See also Note 1 – Summary of Significant Accounting Policies, Note 2 – Rate and Regulatory Matters, Note 10 – Callaway Energy Center, and Note 14 – Related Party Transactions in this report.

Callaway Energy Center

The following table presents insurance coverage at Ameren Missouri’s Callaway energy center at December 31, 2015. The property coverage and the nuclear liability coverage must be renewed on April 1 and January 1, respectively, of each year.



Type and Source of Coverage	Maximum Coverages			Maximum Assessments
Public liability and nuclear worker liability:
American Nuclear Insurers	$	375		$	—
Pool participation	13,114		^(a)	127		^(b)
	$	13,489	^(c)	$	127
Property damage:
Nuclear Electric Insurance Limited	$	2,750	^(d)	$	27	^(e)
European Mutual Association for Nuclear Insurance	500		^(f)	—
	$	3,250		$	27
Replacement power:
Nuclear Electric Insurance Limited	$	490	^(g)	$	10	^(e)


(a)	Provided through mandatory participation in an industrywide retrospective premium assessment program.


(b)	Retrospective premium under the Price-Anderson Act. This is subject to retrospective assessment with respect to a covered loss in excess of $375 million in the event of an incident at any licensed United States commercial reactor, payable at $19 million per year.

(c)

Limit of liability for each incident under the Price-Anderson liability provisions of the Atomic Energy Act of 1954, as amended. A company could be assessed up to $127 million per incident for each licensed reactor it operates, with a maximum of $19 million per incident to be paid in a calendar year for each reactor. This limit is subject to change to account for the effects of inflation and changes in the number of licensed reactors.


(d)	NEIL provides $2.25 billion in property damage, decontamination, and premature decommissioning insurance for both radiation and nonradiation events. An additional $500 million is provided for radiation events only for a total of $2.75 billion.


(e)	All NEIL-insured plants could be subject to assessments should losses exceed the accumulated funds from NEIL.


(f)	European Mutual Association for Nuclear Insurance provides $500 million in excess of the $2.75 billion and $2.25 billion property coverage for radiation and nonradiation events, respectively, provided by NEIL.


(g)	Provides replacement power cost insurance in the event of a prolonged accidental outage. Weekly indemnity is up to $4.5 million for 52 weeks, which commences after the first twelve weeks of an outage, plus up to $3.6 million per week for a minimum of 71 weeks thereafter, for a total not exceeding the policy limit of $490 million. Nonradiation events are sub-limited to $328 million.

The Price-Anderson Act is a federal law that limits the liability for claims from an incident involving any licensed United States commercial nuclear energy center. The limit is based on the number of licensed reactors. The limit of liability and the maximum potential annual payments are adjusted at least every five years for inflation to reflect changes in the Consumer Price Index. The most recent five-year inflationary adjustment became effective in September 2013. Owners of a nuclear reactor cover this exposure through a combination of private insurance and mandatory participation in a financial protection pool, as established by the Price-Anderson Act.

Losses resulting from terrorist attacks on nuclear facilities are covered under NEIL’s policies, subject to an industrywide aggregate policy coverage limit of $3.24 billion within a 12-month period, or $1.83 billion for events not involving radiation contamination.

If losses from a nuclear incident at the Callaway energy center exceed the limits of, or are not covered by, insurance or if coverage is unavailable, Ameren Missouri is at risk for any uninsured losses. If a serious nuclear incident were to occur, it could have a material adverse effect on Ameren’s and Ameren Missouri’s results of operations, financial position, and liquidity.

Leases

We lease various facilities, office equipment, plant equipment, and rail cars under capital and operating leases. The following table presents our lease obligations at December 31, 2015:



	2016		2017		2018		2019		2020		After 5 Years		Total
Ameren:^(a)
Minimum capital lease payments^(b)	$	33	$	33	$	32	$	32	$	32	$	329	$	491
Less amount representing interest	27		27		26		25		25		73		203
Present value of minimum capital lease payments	$	6	$	6	$	6	$	7	$	7	$	256	$	288
Operating leases^(c)	14		13		12		12		11		30		92
Total lease obligations	$	20	$	19	$	18	$	19	$	18	$	286	$	380
Ameren Missouri:
Minimum capital lease payments^(b)	$	33	$	33	$	32	$	32	$	32	$	329	$	491
Less amount representing interest	27		27		26		25		25		73		203
Present value of minimum capital lease payments	$	6	$	6	$	6	$	7	$	7	$	256	$	288
Operating leases^(c)	12		11		11		11		10		29		84
Total lease obligations	$	18	$	17	$	17	$	18	$	17	$	285	$	372
Ameren Illinois:
Operating leases^(c)	$	1	$	1	$	1	$	1	$	1	$	1	$	6


(a)	Includes amounts for Ameren registrant and nonregistrant subsidiaries and intercompany eliminations.


(b)	See Properties under Part I, Item 2, and Note 3 – Property and Plant, Net, of this report for additional information.


(c)	Amounts related to certain land-related leases have indefinite payment periods. The annual obligations of $3 million, $2 million, and $1 million for Ameren, Ameren Missouri, and Ameren Illinois for these items are included in the 2016 through 2020 columns, respectively.

The following table presents total rental expense included in operating expenses for the years ended December 31, 2015, 2014, and 2013:



	2015		2014		2013
Ameren^(a)	$	36	$	37	$	32
Ameren Missouri	34		32		29
Ameren Illinois	28		25		21


(a)	Includes amounts for Ameren registrant and nonregistrant subsidiaries and intercompany eliminations.

Other Obligations

To supply a portion of the fuel requirements of our energy centers, we have entered into various long-term commitments for the procurement of coal, natural gas, nuclear fuel, and methane gas. We also have entered into various long-term commitments for purchased power and natural gas for distribution. The table below presents our estimated fuel, purchased power, and other commitments for fuel at December 31, 2015. Ameren’s and Ameren Missouri’s purchased power commitments include a 102-megawatt power purchase agreement with a wind farm operator, which expires in 2024. Ameren’s and Ameren Illinois’ purchased power commitments include the Ameren Illinois power purchase agreements entered into as part of the IPA-administered power procurement process. Included in the Other column are minimum purchase commitments under contracts for equipment, design and construction, and meter reading services at December 31, 2015.



	Coal		Natural Gas^(a)		Nuclear Fuel		Purchased Power^(b)		Methane Gas		Other		Total
Ameren:^(c)
2016	$	664	$	249	$	51	$	241	$	3	$	115	$	1,323
2017	685		190		46		147		4		73		1,145
2018	204		127		68		72		5		55		531
2019	110		89		24		58		5		56		342
2020	—		43		51		58		6		57		215
Thereafter	—		60		108		539		71		350		1,128
Total	$	1,663	$	758	$	348	$	1,115	$	94	$	706	$	4,684
Ameren Missouri:
2016	$	664	$	46	$	51	$	23	$	3	$	46	$	833
2017	685		36		46		23		4		32		826
2018	204		24		68		23		5		28		352
2019	110		14		24		23		5		29		205
2020	—		10		51		23		6		30		120
Thereafter	—		23		108		84		71		183		469
Total	$	1,663	$	153	$	348	$	199	$	94	$	348	$	2,805
Ameren Illinois:
2016	$	—	$	203	$	—	$	218	$	—	$	31	$	452
2017	—		154		—		124		—		25		303
2018	—		103		—		49		—		24		176
2019	—		75		—		35		—		27		137
2020	—		33		—		35		—		27		95
Thereafter	—		37		—		455		—		167		659
Total	$	—	$	605	$	—	$	916	$	—	$	301	$	1,822


(a)	Includes amounts for generation and for distribution.


(b)	The purchased power amounts for Ameren and Ameren Illinois include agreements through 2032 for renewable energy credits with various renewable energy suppliers. The agreements contain a provision that allows Ameren Illinois to reduce the quantity purchased in the event that Ameren Illinois would not be able to recover the costs associated with the renewable energy credits.


(c)	Includes amounts for Ameren registrant and nonregistrant subsidiaries.

Environmental Matters

We are subject to various environmental laws and regulations enforced by federal, state, and local authorities. From the beginning phases of siting and development to the operation of electric generation, transmission, and distribution facilities and natural gas storage, transmission, and distribution facilities, our activities involve compliance with diverse environmental laws and regulations. These laws and regulations address emissions, discharges to water, water usage, impacts to air, land, and water, and chemical and waste handling. Complex and lengthy processes are required to obtain and renew approvals, permits, and licenses for new, existing or modified facilities. Additionally, the use and handling of various chemicals or hazardous materials require release prevention plans and emergency response procedures.

The EPA has promulgated several environmental regulations that will have a significant impact on the electric utility industry. Over time, compliance with these regulations could be costly for certain companies, including Ameren Missouri, that operate coal-fired power plants. Significant new rules include the regulation of CO₂ emissions from existing power plants through the Clean Power Plan and from new power plants through the revised NSPS; the CSAPR, which requires further reductions of SO₂ emissions and NO_x emissions from power plants; a regulation governing management and storage of CCR; the MATS, which require reduction of emissions of mercury, toxic metals, and acid gases from power plants; revised NSPS for particulate matter, SO₂, and NO_x emissions from new sources; new effluent standards applicable to wastewater discharges from power plants and new regulations under the Clean Water Act that could require significant capital expenditures, such as modifications to water intake structures or new cooling towers at Ameren Missouri’s energy centers. The EPA also periodically reviews and revises national ambient air quality standards, including those standards associated with emissions from power plants, such as particulate matter, ozone, SO₂and NO_x. Certain of these new regulations are being or are likely to be challenged through litigation, so their ultimate implementation, as well as the timing of any such implementation, is uncertain. Although many details of future regulations are unknown, individually or the combined effects of new environmental regulations could result in significant capital expenditures and increased operating costs for Ameren and Ameren Missouri. Compliance with all of these environmental laws and regulations could be prohibitively expensive, result in the closure or alteration of the operation of some of Ameren Missouri’s energy centers, or require capital investment. Ameren and Ameren Missouri expect that these costs would be recoverable through rates, subject to MoPSC prudence review, but the nature and timing of costs could result in regulatory lag.

Ameren Missouri's current plan for compliance with existing environmental regulations for air emissions includes burning ultra-low-sulfur coal and installing new or optimizing existing pollution control equipment. Ameren and Ameren Missouri estimate that they will need to make capital expenditures of $600 million to $700 million in the aggregate from 2016 through 2020 in order to comply with existing environmental regulations. Ameren Missouri may be required to install additional air emissions controls within the next six to 10 years. This estimate includes our capital expenditures required for the CCR regulations that were published in 2015, the rule applicable to cooling water intake structures at existing power plants under the Clean Water Act, and the effluent limitation guidelines applicable to steam electric generating units under the Clean Water Act, all of which are discussed below. These estimates do not include the impacts of the Clean Power Plan discussed below. Considerable uncertainty remains in these estimates. The actual amount of capital expenditures required to comply with existing environmental regulations may vary substantially from the above estimate due to uncertainty as to the precise compliance strategies that will be used and their ultimate cost, among other things.

The following sections describe the more significant new environmental laws and rules and environmental enforcement and remediation matters that affect or could affect our operations.

Clean Air Act

Federal and state laws require significant reductions in SO₂and NO_x through either emission source reductions or the use and retirement of emission allowances. The CSAPR became effective in 2015. There will be further emission reduction requirements in 2017 and potentially more in subsequent years. To achieve compliance with CSAPR, Ameren Missouri burns ultra-low-sulfur coal and operates two scrubbers at its Sioux energy center. Ameren Missouri does not expect to make additional capital investments to comply with the current CSAPR requirements. However, Ameren Missouri expects to incur additional costs as it lowers its emissions at one or more of its energy centers to comply with the CSAPR in future years. These higher costs are expected to be collected from customers through the FAC or higher base rates.

In December 2011, the EPA issued the MATS under the Clean Air Act, which requires reductions in emissions of mercury and other hazardous air pollutants, such as acid gases, trace metals, and hydrogen chloride. The MATS do not require a specific control technology to achieve the emission reductions. The MATS apply to each unit at a coal-fired power plant. However, in certain cases, compliance can be achieved by averaging emissions from similar units at the same power plant. Compliance was required by April 2015 or, with a case-by-case extension, by April 2016. All of Ameren Missouri's coal-fired power plants will be in compliance before the required due dates. As part of Ameren Missouri's compliance plan, the Meramec energy center will burn natural gas at two of its units beginning in April 2016, thereby excluding such units from the MATS. In addition, Ameren Missouri is incurring additional costs to comply with the MATS. These higher costs are being collected from customers through the FAC or higher base rates.

CO₂ Emissions Standards

The Clean Power Plan, which sets forth CO₂emissions standards applicable to existing power plants, was issued by the EPA but stayed by the United States Supreme Court pending the outcome of various appeals, as discussed below.

If the Clean Power Plan is ultimately upheld as issued, Ameren Missouri expects to incur increased fuel and operating costs, and make new or accelerated capital expenditures, in addition to the costs of making modifications to existing operations in order to achieve compliance. The Clean Power Plan required Missouri and Illinois to reduce CO₂ emissions from power plants within their states significantly below 2005 levels by 2030. The rule contains interim compliance periods commencing in 2022 that require each state to demonstrate progress in achieving its CO₂ reduction target. Ameren is evaluating the Clean Power Plan's potential impacts to its operations, including those related to electric system reliability, and to its level of investment in customer energy efficiency programs, renewable energy, and other forms of generation investment. Significant uncertainty exists regarding the impact of the Clean Power Plan, as its implementation will depend upon plans to be developed by the states. Numerous legal challenges are pending, which could result in the rule being declared invalid or the nature and timing of CO₂ emissions reductions being revised. In February 2016, the United States Supreme Court stayed the Clean Power Plan and all implementation requirements until such time as legal appeals are concluded. The District of Columbia Circuit Court of Appeals has scheduled hearings for June 2016 on the legality of the rule. A decision by the District of Columbia Circuit Court of Appeals is expected to be issued later this year and additional appeals before the United States Supreme Court are likely. Appeals are not expected to conclude prior to 2018. We cannot predict the outcome of such legal challenges or their impact on our results of operations, financial position, or liquidity. If the rule is ultimately upheld and implemented in substantially similar form to the rule when issued, compliance measures could result in the closure or alteration of the operation of some of Ameren Missouri’s coal and natural-gas-fired energy centers, which could result in increased operating costs. Ameren Missouri expects substantially all of these increased costs to be recoverable, subject to MoPSC prudence review, through higher rates to customers, which could be significant.

Also, in August 2015, the EPA issued final regulations that set CO₂ emissions standards for new power plants. These new standards establish separate emissions limits for new natural-gas-fired combined cycle plants and new coal-fired plants.

Federal and state legislation or regulations that mandate limits on the emission of CO₂ may result in significant increases in capital expenditures and operating costs, which could lead to increased liquidity needs and higher financing costs. Mandatory limits on the emission of CO₂ could increase costs for Ameren Missouri’s customers or have a material adverse effect on Ameren's and Ameren Missouri's results of operations, financial position, and liquidity if regulators delay or deny recovery in rates of these compliance costs. The cost of Ameren Illinois’ purchased power and gas purchased for resale could increase. However, Ameren Illinois expects these costs would be recovered from customers with no material adverse effect on its results of operations, financial position, or liquidity. Ameren's and Ameren Missouri's earnings might benefit from increased investment to comply with CO₂ emission limitations to the extent that the investments are reflected and recovered on a timely basis in rates charged to customers.

NSR and Clean Air Litigation

In January 2011, the Department of Justice, on behalf of the EPA, filed a complaint against Ameren Missouri in the United States District Court for the Eastern District of Missouri. The EPA's complaint, as amended in October 2013, alleges that in performing projects at its Rush Island coal-fired energy center in 2007 and 2010, Ameren Missouri violated provisions of the Clean Air Act and Missouri law. Ameren Missouri anticipates that a trial of this case could occur as early as 2016. Ameren Missouri believes its defenses are meritorious and is defending itself vigorously. However, there can be no assurances that it will be successful in its efforts.

The ultimate resolution of this matter could have a material adverse effect on the results of operations, financial position, and liquidity of Ameren and Ameren Missouri. A resolution of this matter could result in increased capital expenditures for the installation of pollution control equipment and increased operations and maintenance expenses. We are unable to predict the ultimate resolution of these matters or the costs that might be incurred.

Clean Water Act

In August 2014, the EPA issued its final rule applicable to cooling water intake structures at existing power plants. The rule requires a case-by-case evaluation and plan for reducing aquatic organisms impinged on the facility’s intake screens or entrained through the plant's cooling water system. All of Ameren Missouri’s coal-fired and nuclear energy centers are subject to this rule. Each of Ameren Missouri’s affected energy centers will become subject to the revised limitations when it renews its water discharge permit. These permits are scheduled to be renewed between 2018 and 2023. The rule could have an adverse effect on Ameren’s and Ameren Missouri’s results of operations, financial position, and liquidity if its implementation requires the installation of cooling towers or extensive modifications to the cooling water systems at our energy centers and if those investments are not recovered on a timely basis in electric rates charged to Ameren Missouri's customers.

In September 2015, the EPA issued its final rule under the Clean Water Act to revise the effluent limitation guidelines applicable to steam electric generating units. Effluent limitation guidelines are national standards for water discharges that are based on the effectiveness of available control technology. The EPA's rule prohibits effluent discharges of certain, but not all, waste streams and imposes more stringent limitations on certain components in water discharges from power plants. All of Ameren Missouri’s coal-fired energy centers are subject to this rule and its implementation will be consistent with the water discharge permit process described above beginning as early as 2018. Ameren Missouri is evaluating the final rule, which became effective in January 2016, and the possible effects on its operations.

Ash Management

In 2015, the EPA issued regulations regarding the management and disposal of CCR, that will affect future CCR disposal and handling costs at Ameren Missouri's energy centers. The regulations allow for the management of CCR as a solid waste, as well as for its continued beneficial uses, such as recycling, which could reduce the amount to be disposed. The regulations also establish criteria regarding the structural integrity, location, and operation of CCR impoundments and landfills. They require groundwater monitoring and closure of impoundments if the groundwater standards are not achieved. During 2015, Ameren and Ameren Missouri recorded an increase to their AROs associated with CCR storage facilities and accelerated the closure of certain CCR storage facilities at its energy centers as a result of the new regulations. Ameren Missouri plans to close these CCR storage facilities between 2018 and 2023. See Note 1 – Summary of Significant Accounting Policies in this report for additional information. Ameren Missouri's capital expenditure plan includes the cost of constructing landfills as part of its environmental compliance plan.

The new regulations do not apply to ash ponds at plants no longer in operation, such as Ameren’s Meredosia and Hutsonville energy centers.

Remediation

The Ameren Companies are involved in a number of remediation actions to clean up sites affected by hazardous substances, as required by federal and state law. Such laws require that responsible parties fund remediation actions regardless of their degree of fault, the legality of original disposal, or the ownership of a disposal site. Ameren Missouri and Ameren Illinois have each been identified by federal or state governments as a potentially responsible party at several contaminated sites.

As of December 31, 2015, Ameren Illinois owned or was otherwise responsible for 44 former MGP sites in Illinois, which are in various stages of investigation, evaluation, remediation, and closure. Ameren Illinois estimates it could substantially conclude remediation efforts by 2025. The ICC allows Ameren Illinois to recover remediation and litigation costs associated with its former MGP sites from its electric and natural gas utility customers through environmental adjustment rate riders. Costs are subject to annual prudence review by the ICC. As of December 31, 2015, Ameren Illinois estimated the obligation related to these former MGP sites at $232 million to $313 million. Ameren and Ameren Illinois recorded a liability of $232 million to represent their estimated minimum obligation for these sites, as no other amount within the range was a better estimate.

The scope and extent to which these former MGP sites are remediated may increase as remediation efforts continue. Considerable uncertainty remains in these estimates, as many factors can influence the ultimate actual costs, including site-specific unanticipated underground structures, the degree to which groundwater is encountered, regulatory changes, local ordinances, and site accessibility. The actual costs may vary substantially from these estimates.

Ameren Illinois formerly used an off-site landfill, which Ameren Illinois did not own, in connection with the operation of a previously owned energy center. Ameren Illinois could be required to perform certain maintenance activities at that landfill, which is now closed. As of December 31, 2015, Ameren Illinois estimated the obligation related to this site at $0.5 million to $6 million. Ameren Illinois recorded a liability of $0.5 million to represent its estimated minimum obligation for this site, as no other amount within the range was a better estimate. Ameren Illinois is also responsible for the cleanup of some underground storage tanks and a water treatment plant in Illinois. As of December 31, 2015, Ameren Illinois recorded a liability of $0.7 million to represent its best estimate of the obligation for these sites.

In 2008, the EPA issued an administrative order to Ameren Missouri pertaining to a former coal tar distillery in St. Louis, Missouri, operated by Koppers Company or its predecessor and successor companies. While Ameren Missouri is the current owner of the site, it did not conduct any of the manufacturing operations involving coal tar or its byproducts. Ameren Missouri, along with two other potentially responsible parties, have completed site investigation activities and have submitted their findings to the EPA. As of December 31, 2015, Ameren Missouri estimated its obligation at $2 million to $5 million. Ameren Missouri recorded a liability of $2 million to represent its estimated minimum obligation, as no other amount within the range was a better estimate.

Ameren Missouri also participated in the investigation of several sites located in Sauget, Illinois. In 2000, the EPA notified Ameren Missouri and numerous other companies, including Solutia, Inc., that former landfills and lagoons at those sites may contain soil and groundwater contamination. These sites are known as Sauget Area 2. From about 1926 until 1976, Ameren Missouri operated an energy center adjacent to Sauget Area 2. Ameren Missouri currently owns a parcel of property at Sauget Area 2 that was once used as a landfill.

In December 2013, the EPA issued its record of decision for Sauget Area 2 approving the investigation and the remediation alternatives recommended by the potentially responsible parties. Further negotiation among the potentially responsible parties will determine how to fund the implementation of the EPA-approved cleanup remedies. As of December 31, 2015, Ameren Missouri estimated its obligation related to Sauget Area 2 at $1 million to $2.5 million. Ameren Missouri recorded a liability of $1 million to represent its estimated minimum obligation, as no other amount within the range was a better estimate.

In December 2012, Ameren Missouri signed an administrative order with the EPA and agreed to investigate soil and groundwater conditions at an Ameren Missouri-owned substation in St. Charles, Missouri. As of December 31, 2015, Ameren Missouri estimated and recorded a $0.6 million liability related to the site. Although monitoring will continue for some time, no significant additional remediation measures are anticipated.

Our operations or those of our predecessor companies involve the use of, disposal of, and in appropriate circumstances, the cleanup of substances regulated under environmental laws. We are unable to determine whether such practices will result in future environmental commitments or will affect our results of operations, financial position, or liquidity.

Pumped-storage Hydroelectric Facility Breach

In December 2005, there was a breach of the upper reservoir at Ameren Missouri's Taum Sauk pumped-storage hydroelectric energy center. The breach resulted in significant flooding in the local area, which damaged a state park. Ameren Missouri had liability insurance coverage for the Taum Sauk incident, subject to certain limits and deductibles.

As of December 31, 2015, Ameren Missouri had an insurance receivable of $41 million. In February 2016, Ameren Missouri and an insurer that was providing Ameren Missouri with liability coverage on the date of the Taum Sauk incident reached a settlement that resulted in Ameren Missouri receiving $42 million. As a result of this settlement, the receivable was included in “Miscellaneous accounts and notes receivable” on Ameren’s and Ameren Missouri’s balance sheets as of December 31, 2015 whereas previously this receivable was included in “Other assets” on their respective balance sheets as of December 31, 2014.

Asbestos-related Litigation

Ameren, Ameren Missouri, and Ameren Illinois have been named, along with numerous other parties, in a number of lawsuits filed by plaintiffs claiming varying degrees of injury from asbestos exposure at our present or former energy centers. Most have been filed in the Circuit Court of Madison County, Illinois. The total number of defendants named in each case varies, with 75 as the average number of parties as of December 31, 2015. Each lawsuit seeks unspecified damages that, if awarded at trial, typically would be shared among the various defendants.

The following table presents the pending asbestos-related lawsuits filed against Ameren Missouri and Ameren Illinois as of December 31, 2015:



Ameren Missouri	Ameren Illinois	Total^(a)
26	38	48


(a)	Total does not equal the sum of the subsidiary unit lawsuits because some of the lawsuits name multiple Ameren entities as defendants.

At December 31, 2015, Ameren, Ameren Missouri, and Ameren Illinois had liabilities of $8 million, $3 million, and $5 million, respectively, recorded to represent their best estimates of their obligations related to asbestos claims.

Ameren Illinois has a tariff rider to recover the costs of IP asbestos-related litigation claims, subject to the following terms: 90% of the cash expenditures in excess of the amount included in base electric rates is to be recovered from a trust fund that was established when Ameren acquired IP. At December 31, 2015, the trust fund balance was $22 million, including accumulated interest. If cash expenditures are less than the amount in base rates, Ameren Illinois will contribute 90% of the difference to the trust fund. Once the trust fund is depleted, 90% of allowed cash expenditures in excess of base rates will be recovered through charges assessed to customers under the tariff rider. The rider will permit recovery from electric customers within IP’s historical service territory.

Ameren Missouri Municipal Taxes

The cities of Creve Coeur and Winchester, Missouri, on behalf of themselves and other municipalities in Ameren Missouri’s service area, filed a class action lawsuit in November 2011 against Ameren Missouri in the Circuit Court of St. Louis County, Missouri. The lawsuit alleges that Ameren Missouri failed to collect and pay gross receipts taxes or license fees on certain revenues. Ameren and Ameren Missouri recorded immaterial liabilities on their respective balance sheets as of December 31, 2015, representing their estimate of taxes and fees due as a result of this lawsuit. The ultimate resolution of any unpaid municipal tax or fees could have a material adverse effect on the results of operations, financial position, and liquidity of Ameren and Ameren Missouri. Ameren Missouri believes its defenses are meritorious and is defending itself vigorously; however, there can be no assurances that Ameren Missouri will be successful in its efforts.