Callaway Energy Center	6 Months Ended
Jun. 30, 2011
Callaway Energy Center	NOTE 10 - CALLAWAY ENERGY CENTER Under the Nuclear Waste Policy Act of 1982, the DOE is responsible for the permanent storage and disposal of spent nuclear fuel. The DOE currently charges one mill, or one-tenth of one cent, per nuclear-generated kilowatthour sold for future disposal of spent fuel (the NWF fee). Pursuant to this act, Ameren Missouri collects one mill from its electric customers for each kilowatthour of electricity that it generates and sells from its Callaway energy center. Electric utility rates charged to customers provide for recovery of such costs. Ameren Missouri has sufficient installed storage capacity for spent nuclear fuel at its Callaway energy center until 2020. It has the capability for additional storage capacity through the licensed life of the energy center. In March 2010, the DOE submitted a motion to withdraw the Yucca Mountain Repository license application it filed with the NRC. In anticipation of this action, the Nuclear Energy Institute (NEI) in July 2009 formally requested that DOE promptly perform the statutorily required annual fee adequacy review and immediately suspend collection of the NWF fee. The Nuclear Waste Policy Act mandates that DOE compare the revenue generated by the NWF fee with the costs of the waste disposal program and adjust the size of the NWF fee to match the cost of the program. In the past, the cost of the program reviewed by DOE for NWF fee adequacy has been the cost of constructing and operating the Yucca Mountain Repository. The DOE declined to eliminate or reduce the NWF fee. As a result, NEI and the National Association of Regulatory Utility Commissioners (NARUC) filed petitions for review in the United States Court of Appeals for the District of Columbia Circuit seeking suspension of the NWF fee due to the DOE's motion to withdraw the application. These lawsuits were consolidated, and in December 2010 the court dismissed the petitions for review as moot (with respect to asking DOE to conduct the annual fee adequacy review) and rejected the request to suspend the fee. In March 2011, NEI and 16 of its member companies filed suit in the United States Court of Appeals for the District of Columbia Circuit again challenging the continued collection of the NWF fee. The lawsuit contends that the DOE's review of the need to continue to collect the NWF fee, which resulted in the dismissal of the earlier lawsuit as moot, is inadequate and that collection of the NWF fee should be suspended. NARUC also filed suit against the DOE in the United States Court of Appeals for the District of Columbia Circuit in March 2011, questioning the veracity of the DOE's fee adequacy assessment and seeking similar relief. The DOE has established the Blue Ribbon Commission on America's Nuclear Future to conduct a comprehensive review of policies for managing certain components of the nuclear fuel cycle, including all alternatives for the storage, processing, and disposal of civilian and defense used nuclear fuel, high-level waste, and materials derived from nuclear activities. The Blue Ribbon Commission report will be only advisory and its draft report was submitted on July 29, 2011. The delayed availability of the DOE's disposal facility is not expected to adversely affect the continued operation of the Callaway energy center through its currently licensed life. In 1984, the DOE entered into a contract with Ameren Missouri to dispose of nuclear waste from its Callaway energy center. As a result of DOE's failure to build a repository for nuclear waste or otherwise fulfill its contract obligations, Ameren Missouri and other nuclear power plant owners sued DOE to recover costs incurred for ongoing storage of their spent fuel. Ameren Missouri filed suit in 2004 to recover approximately $13 million in costs that it incurred through 2009. This amount included the cost of reracking the Callaway energy center's spent fuel pool, as well as certain NRC fees, and Missouri ad valorem taxes that Ameren Missouri would not have incurred had DOE performed its contractual obligations. In December 2010, Ameren Missouri and DOE began investigating settlement options, and in June 2011 the parties reached a settlement. The terms of the settlement include payment to Ameren Missouri of approximately $11 million for spent fuel storage and related costs through 2010, and thereafter, annual payment of such costs after they are incurred through 2013 or any other mutually agreed extension. As a result of this settlement agreement, Ameren Missouri recorded a pretax reduction of $2 million and $2 million to its depreciation and amortization and other operations and maintenance line items, respectively, on its statement of income for the three and six months ended June 30, 2011. Ameren Missouri reduced its property and plant assets by $7 million. Ameren Missouri received the DOE settlement amount in July 2011. Under the settlement, Ameren Missouri's breach of contract suit will be dismissed. Ameren Missouri intends to submit a license extension application with the NRC to extend its Callaway energy center's operating license from 2024 to 2044. If the Callaway energy center's license is extended, additional spent fuel storage will be required. Ameren Missouri plans to install a dry spent fuel storage facility at its Callaway energy center and intends to begin transferring spent fuel assemblies to this facility prior to 2020. Electric utility rates charged to customers provide for the recovery of the Callaway energy center's decommissioning costs, which include decontamination, dismantling, and site restoration costs, over an assumed 40-year life of the nuclear center, ending with the expiration of the energy center's operating license in 2024. It is assumed that the Callaway energy center site will be decommissioned based on the immediate dismantlement method and removed from service. Ameren and Ameren Missouri have recorded an ARO for the Callaway energy center decommissioning costs at fair value, which represents the present value of estimated future cash outflows. Decommissioning costs are included in the costs of service used to establish electric rates for Ameren Missouri's customers. These costs amounted to $7 million in each of the years 2010, 2009, and 2008. Every three years, the MoPSC requires Ameren Missouri to file an updated cost study for decommissioning its Callaway energy center. Electric rates may be adjusted at such times to reflect changed estimates. The latest cost study filed in September 2008 included the minor tritium contamination discovered on the Callaway energy center site, which did not result in a significant increase in the decommissioning cost estimate. Ameren Missouri expects to file a new cost study in the third quarter of 2011. Amounts collected from customers are deposited in an external trust fund to provide for the Callaway energy center's decommissioning. If the assumed return on trust assets is not earned, we believe that it is probable that any such earnings deficiency will be recovered in rates. The fair value of the nuclear decommissioning trust fund for Ameren Missouri's Callaway energy center is reported as Nuclear Decommissioning Trust Fund in Ameren's Consolidated Balance Sheet and Ameren Missouri's Balance Sheet. This amount is legally restricted and may be used only to fund the costs of nuclear decommissioning. Changes in the fair value of the trust fund are recorded as an increase or decrease to the nuclear decommissioning trust fund, with an offsetting adjustment to the related regulatory asset or regulatory liability.
Union Electric Company [Member]
Callaway Energy Center	NOTE 10 - CALLAWAY ENERGY CENTER Under the Nuclear Waste Policy Act of 1982, the DOE is responsible for the permanent storage and disposal of spent nuclear fuel. The DOE currently charges one mill, or one-tenth of one cent, per nuclear-generated kilowatthour sold for future disposal of spent fuel (the NWF fee). Pursuant to this act, Ameren Missouri collects one mill from its electric customers for each kilowatthour of electricity that it generates and sells from its Callaway energy center. Electric utility rates charged to customers provide for recovery of such costs. Ameren Missouri has sufficient installed storage capacity for spent nuclear fuel at its Callaway energy center until 2020. It has the capability for additional storage capacity through the licensed life of the energy center. In March 2010, the DOE submitted a motion to withdraw the Yucca Mountain Repository license application it filed with the NRC. In anticipation of this action, the Nuclear Energy Institute (NEI) in July 2009 formally requested that DOE promptly perform the statutorily required annual fee adequacy review and immediately suspend collection of the NWF fee. The Nuclear Waste Policy Act mandates that DOE compare the revenue generated by the NWF fee with the costs of the waste disposal program and adjust the size of the NWF fee to match the cost of the program. In the past, the cost of the program reviewed by DOE for NWF fee adequacy has been the cost of constructing and operating the Yucca Mountain Repository. The DOE declined to eliminate or reduce the NWF fee. As a result, NEI and the National Association of Regulatory Utility Commissioners (NARUC) filed petitions for review in the United States Court of Appeals for the District of Columbia Circuit seeking suspension of the NWF fee due to the DOE's motion to withdraw the application. These lawsuits were consolidated, and in December 2010 the court dismissed the petitions for review as moot (with respect to asking DOE to conduct the annual fee adequacy review) and rejected the request to suspend the fee. In March 2011, NEI and 16 of its member companies filed suit in the United States Court of Appeals for the District of Columbia Circuit again challenging the continued collection of the NWF fee. The lawsuit contends that the DOE's review of the need to continue to collect the NWF fee, which resulted in the dismissal of the earlier lawsuit as moot, is inadequate and that collection of the NWF fee should be suspended. NARUC also filed suit against the DOE in the United States Court of Appeals for the District of Columbia Circuit in March 2011, questioning the veracity of the DOE's fee adequacy assessment and seeking similar relief. The DOE has established the Blue Ribbon Commission on America's Nuclear Future to conduct a comprehensive review of policies for managing certain components of the nuclear fuel cycle, including all alternatives for the storage, processing, and disposal of civilian and defense used nuclear fuel, high-level waste, and materials derived from nuclear activities. The Blue Ribbon Commission report will be only advisory and its draft report was submitted on July 29, 2011. The delayed availability of the DOE's disposal facility is not expected to adversely affect the continued operation of the Callaway energy center through its currently licensed life. In 1984, the DOE entered into a contract with Ameren Missouri to dispose of nuclear waste from its Callaway energy center. As a result of DOE's failure to build a repository for nuclear waste or otherwise fulfill its contract obligations, Ameren Missouri and other nuclear power plant owners sued DOE to recover costs incurred for ongoing storage of their spent fuel. Ameren Missouri filed suit in 2004 to recover approximately $13 million in costs that it incurred through 2009. This amount included the cost of reracking the Callaway energy center's spent fuel pool, as well as certain NRC fees, and Missouri ad valorem taxes that Ameren Missouri would not have incurred had DOE performed its contractual obligations. In December 2010, Ameren Missouri and DOE began investigating settlement options, and in June 2011 the parties reached a settlement. The terms of the settlement include payment to Ameren Missouri of approximately $11 million for spent fuel storage and related costs through 2010, and thereafter, annual payment of such costs after they are incurred through 2013 or any other mutually agreed extension. As a result of this settlement agreement, Ameren Missouri recorded a pretax reduction of $2 million and $2 million to its depreciation and amortization and other operations and maintenance line items, respectively, on its statement of income for the three and six months ended June 30, 2011. Ameren Missouri reduced its property and plant assets by $7 million. Ameren Missouri received the DOE settlement amount in July 2011. Under the settlement, Ameren Missouri's breach of contract suit will be dismissed. Ameren Missouri intends to submit a license extension application with the NRC to extend its Callaway energy center's operating license from 2024 to 2044. If the Callaway energy center's license is extended, additional spent fuel storage will be required. Ameren Missouri plans to install a dry spent fuel storage facility at its Callaway energy center and intends to begin transferring spent fuel assemblies to this facility prior to 2020. Electric utility rates charged to customers provide for the recovery of the Callaway energy center's decommissioning costs, which include decontamination, dismantling, and site restoration costs, over an assumed 40-year life of the nuclear center, ending with the expiration of the energy center's operating license in 2024. It is assumed that the Callaway energy center site will be decommissioned based on the immediate dismantlement method and removed from service. Ameren and Ameren Missouri have recorded an ARO for the Callaway energy center decommissioning costs at fair value, which represents the present value of estimated future cash outflows. Decommissioning costs are included in the costs of service used to establish electric rates for Ameren Missouri's customers. These costs amounted to $7 million in each of the years 2010, 2009, and 2008. Every three years, the MoPSC requires Ameren Missouri to file an updated cost study for decommissioning its Callaway energy center. Electric rates may be adjusted at such times to reflect changed estimates. The latest cost study filed in September 2008 included the minor tritium contamination discovered on the Callaway energy center site, which did not result in a significant increase in the decommissioning cost estimate. Ameren Missouri expects to file a new cost study in the third quarter of 2011. Amounts collected from customers are deposited in an external trust fund to provide for the Callaway energy center's decommissioning. If the assumed return on trust assets is not earned, we believe that it is probable that any such earnings deficiency will be recovered in rates. The fair value of the nuclear decommissioning trust fund for Ameren Missouri's Callaway energy center is reported as Nuclear Decommissioning Trust Fund in Ameren's Consolidated Balance Sheet and Ameren Missouri's Balance Sheet. This amount is legally restricted and may be used only to fund the costs of nuclear decommissioning. Changes in the fair value of the trust fund are recorded as an increase or decrease to the nuclear decommissioning trust fund, with an offsetting adjustment to the related regulatory asset or regulatory liability.

Callaway Energy Center

6 Months Ended

Jun. 30, 2011

NOTE 10 - CALLAWAY ENERGY CENTER

Under the Nuclear Waste Policy Act of 1982, the DOE is responsible for the permanent storage and disposal of spent nuclear fuel. The DOE currently charges one mill, or one-tenth of one cent, per nuclear-generated kilowatthour sold for future disposal of spent fuel (the NWF fee). Pursuant to this act, Ameren Missouri collects one mill from its electric customers for each kilowatthour of electricity that it generates and sells from its Callaway energy center. Electric utility rates charged to customers provide for recovery of such costs. Ameren Missouri has sufficient installed storage capacity for spent nuclear fuel at its Callaway energy center until 2020. It has the capability for additional storage capacity through the licensed life of the energy center. In March 2010, the DOE submitted a motion to withdraw the Yucca Mountain Repository license application it filed with the NRC. In anticipation of this action, the Nuclear Energy Institute (NEI) in July 2009 formally requested that DOE promptly perform the statutorily required annual fee adequacy review and immediately suspend collection of the NWF fee. The Nuclear Waste Policy Act mandates that DOE compare the revenue generated by the NWF fee with the costs of the waste disposal program and adjust the size of the NWF fee to match the cost of the program. In the past, the cost of the program reviewed by DOE for NWF fee adequacy has been the cost of constructing and operating the Yucca Mountain Repository. The DOE declined to eliminate or reduce the NWF fee. As a result, NEI and the National Association of Regulatory Utility Commissioners (NARUC) filed petitions for review in the United States Court of Appeals for the District of Columbia Circuit seeking suspension of the NWF fee due to the DOE's motion to withdraw the application. These lawsuits were consolidated, and in December 2010 the court dismissed the petitions for review as moot (with respect to asking DOE to conduct the annual fee adequacy review) and rejected the request to suspend the fee. In March 2011, NEI and 16 of its member companies filed suit in the United States Court of Appeals for the District of Columbia Circuit again challenging the continued collection of the NWF fee. The lawsuit contends that the DOE's review of the need to continue to collect the NWF fee, which resulted in the dismissal of the earlier lawsuit as moot, is inadequate and that collection of the NWF fee should be suspended. NARUC also filed suit against the DOE in the United States Court of Appeals for the District of Columbia Circuit in March 2011, questioning the veracity of the DOE's fee adequacy assessment and seeking similar relief.

The DOE has established the Blue Ribbon Commission on America's Nuclear Future to conduct a comprehensive review of policies for managing certain components of the nuclear fuel cycle, including all alternatives for the storage, processing, and disposal of civilian and defense used nuclear fuel, high-level waste, and materials derived from nuclear activities. The Blue Ribbon Commission report will be only advisory and its draft report was submitted on July 29, 2011. The delayed availability of the DOE's disposal facility is not expected to adversely affect the continued operation of the Callaway energy center through its currently licensed life.

In 1984, the DOE entered into a contract with Ameren Missouri to dispose of nuclear waste from its Callaway energy center. As a result of DOE's failure to build a repository for nuclear waste or otherwise fulfill its contract obligations, Ameren Missouri and other nuclear power plant owners sued DOE to recover costs incurred for ongoing storage of their spent fuel. Ameren Missouri filed suit in 2004 to recover approximately $13 million in costs that it incurred through 2009. This amount included the cost of reracking the Callaway energy center's spent fuel pool, as well as certain NRC fees, and Missouri ad valorem taxes that Ameren Missouri would not have incurred had DOE performed its contractual obligations. In December 2010, Ameren Missouri and DOE began investigating settlement options, and in June 2011 the parties reached a settlement. The terms of the settlement include payment to Ameren Missouri of approximately $11 million for spent fuel storage and related costs through 2010, and thereafter, annual payment of such costs after they are incurred through 2013 or any other mutually agreed extension. As a result of this settlement agreement, Ameren Missouri recorded a pretax reduction of $2 million and $2 million to its depreciation and amortization and other operations and maintenance line items, respectively, on its statement of income for the three and six months ended June 30, 2011. Ameren Missouri reduced its property and plant assets by $7 million. Ameren Missouri received the DOE settlement amount in July 2011. Under the settlement, Ameren Missouri's breach of contract suit will be dismissed.

Ameren Missouri intends to submit a license extension application with the NRC to extend its Callaway energy center's operating license from 2024 to 2044. If the Callaway energy center's license is extended, additional spent fuel storage will be required. Ameren Missouri plans to install a dry spent fuel storage facility at its Callaway energy center and intends to begin transferring spent fuel assemblies to this facility prior to 2020.

Electric utility rates charged to customers provide for the recovery of the Callaway energy center's decommissioning costs, which include decontamination, dismantling, and site restoration costs, over an assumed 40-year life of the nuclear center, ending with the expiration of the energy center's operating license in 2024. It is assumed that the Callaway energy center site will be decommissioned based on the immediate dismantlement method and removed from service. Ameren and Ameren Missouri have recorded an ARO for the Callaway energy center decommissioning costs at fair value, which represents the present value of estimated future cash outflows. Decommissioning costs are included in the costs of service used to establish electric rates for Ameren Missouri's customers. These costs amounted to $7 million in each of the years 2010, 2009, and 2008. Every three years, the MoPSC requires Ameren Missouri to file an updated cost study for decommissioning its Callaway energy center. Electric rates may be adjusted at such times to reflect changed estimates. The latest cost study filed in September 2008 included the minor tritium contamination discovered on the Callaway energy center site, which did not result in a significant increase in the decommissioning cost estimate. Ameren Missouri expects to file a new cost study in the third quarter of 2011. Amounts collected from customers are deposited in an external trust fund to provide for the Callaway energy center's decommissioning. If the assumed return on trust assets is not earned, we believe that it is probable that any such earnings deficiency will be recovered in rates. The fair value of the nuclear decommissioning trust fund for Ameren Missouri's Callaway energy center is reported as Nuclear Decommissioning Trust Fund in Ameren's Consolidated Balance Sheet and Ameren Missouri's Balance Sheet. This amount is legally restricted and may be used only to fund the costs of nuclear decommissioning. Changes in the fair value of the trust fund are recorded as an increase or decrease to the nuclear decommissioning trust fund, with an offsetting adjustment to the related regulatory asset or regulatory liability.

Union Electric Company [Member]

Callaway Energy Center

NOTE 10 - CALLAWAY ENERGY CENTER