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Contingencies and Commitments | 6 Months Ended
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Jun. 30, 2018
Site Contingency [Line Items] |
Contingencies and Commitments | Contingencies and Commitments CMS Energy and Consumers are involved in various matters that give rise to contingent liabilities. Depending on the specific issues, the resolution of these contingencies could negatively affect CMS Energy’s and Consumers’ liquidity, financial condition, and results of operations. In their disclosures of these matters, CMS Energy and Consumers provide an estimate of the possible loss or range of loss when such an estimate can be made. Disclosures that state that CMS Energy or Consumers cannot predict the outcome of a matter indicate that they are unable to estimate a possible loss or range of loss for the matter. CMS Energy Contingencies Gas Index Price Reporting Litigation: CMS Energy, along with CMS MST, CMS Field Services, Cantera Natural Gas, Inc., and Cantera Gas Company, were named as defendants in four class action lawsuits and one individual lawsuit arising as a result of alleged inaccurate natural gas price reporting to publications that report trade information. Allegations include price-fixing conspiracies, restraint of trade, and artificial inflation of natural gas retail prices in Kansas, Missouri, and Wisconsin. In 2016, CMS Energy entities reached a settlement with the plaintiffs in the Kansas and Missouri class action cases for an amount that was not material to CMS Energy. In August 2017, the federal district court approved the settlement. Plaintiffs are making claims for the following: treble damages, full consideration damages, exemplary damages, costs, interest, and/or attorneys’ fees. After removal to federal court, all of the cases were transferred to a single federal district court pursuant to the multidistrict litigation process. In 2010 and 2011, all claims against CMS Energy defendants were dismissed by the district court based on FERC preemption. In 2013, the U.S. Court of Appeals for the Ninth Circuit reversed the district court decision. The appellate court found that FERC preemption does not apply under the facts of these cases. The appellate court affirmed the district court’s denial of leave to amend to add federal antitrust claims. The matter was appealed to the U.S. Supreme Court, which in 2015 upheld the Ninth Circuit’s decision. The cases were remanded back to the federal district court. In 2016, the federal district court granted the defendants’ motion for summary judgment in the individual lawsuit filed in Kansas based on a release in a prior settlement involving similar allegations; the order of summary judgment was subsequently appealed. In March 2018, the U.S. Court of Appeals for the Ninth Circuit reversed the lower court’s ruling and remanded the case back to the federal district court. In March 2017, the federal district court denied plaintiffs’ motion for class certification in the two pending class action cases. The plaintiffs appealed that decision to the U.S. Court of Appeals for the Ninth Circuit, which has accepted the matter for hearing. In June 2017, an unaffiliated company that is also a defendant in these cases filed for bankruptcy, which could increase the risk of loss to CMS Energy. These cases involve complex facts, a large number of similarly situated defendants with different factual positions, and multiple jurisdictions. Presently, any estimate of liability would be highly speculative; the amount of CMS Energy’s reasonably possible loss would be based on widely varying models previously untested in this context. If the outcome after appeals is unfavorable, these cases could negatively affect CMS Energy’s liquidity, financial condition, and results of operations. Bay Harbor: CMS Land retained environmental remediation obligations for the collection and treatment of leachate, a liquid consisting of water and other substances, at Bay Harbor after selling its interests in the development in 2002. Leachate is produced when water enters into cement kiln dust piles left over from former cement plant operations at the site. In 2012, CMS Land and the MDEQ finalized an agreement that established the final remedies and the future water quality criteria at the site. CMS Land completed all construction necessary to implement the remedies required by the agreement and will continue to maintain and operate a system to discharge treated leachate into Little Traverse Bay under an NPDES permit issued in 2010 and renewed in 2016. The renewed NPDES permit is valid through September 2020. Various claims have been brought against CMS Land or its affiliates, including CMS Energy, alleging environmental damage to property, loss of property value, insufficient disclosure of environmental matters, breach of agreement relating to access, or other matters. CMS Land and other parties have received a demand for payment from the EPA in the amount of $8 million, plus interest and costs. The EPA is seeking recovery under CERCLA of response costs allegedly incurred at Bay Harbor. These costs exceed what was agreed to in a 2005 order between CMS Land and the EPA and CMS Land believes that the claim was made beyond the appropriate statute of limitations. CMS Land has communicated to the EPA that it does not believe that this is a valid claim. The EPA has filed a lawsuit to collect these costs. At June 30, 2018, CMS Energy had a recorded liability of $47 million for its remaining obligations for environmental remediation. CMS Energy calculated this liability based on discounted projected costs, using a discount rate of 4.34 percent and an inflation rate of one percent on annual operating and maintenance costs. The undiscounted amount of the remaining obligation is $58 million. CMS Energy expects to pay the following amounts for long-term liquid disposal and operating and maintenance costs during the remainder of 2018 and in each of the next five years:
In Millions |
| 2018 |  | 2019 |  | 2020 |  | 2021 |  | 2022 |  | 2023 |
CMS Energy |  |  |  |  |  |  |  |  |  |  |  |
Long-term liquid disposal and operating and maintenance costs |  | $ | 2 |  |  | $ | 4 |  |  | $ | 4 |  |  | $ | 4 |  |  | $ | 4 |  |  | $ | 4 |
CMS Energy’s estimate of response activity costs and the timing of expenditures could change if there are changes in circumstances or assumptions used in calculating the liability. Although a liability for its present estimate of remaining response activity costs has been recorded, CMS Energy cannot predict the ultimate financial impact or outcome of this matter. Equatorial Guinea Tax Claim: In 2002, CMS Energy sold its oil, gas, and methanol investments in Equatorial Guinea. The government of Equatorial Guinea claims that, in connection with the sale, CMS Energy owes $152 million in taxes, plus substantial penalties and interest that could be up to the amount of the taxes claimed. In 2015, the matter was proceeding to formal arbitration; however, since then, the government of Equatorial Guinea has stopped communicating. CMS Energy has concluded that the government’s tax claim is without merit and will continue to contest the claim, but cannot predict the financial impact or outcome of the matter. An unfavorable outcome could have a material adverse effect on CMS Energy’s liquidity, financial condition, and results of operations. Consumers Electric Utility Contingencies Electric Environmental Matters: Consumers’ operations are subject to environmental laws and regulations. Historically, Consumers has generally been able to recover, in customer rates, the costs to operate its facilities in compliance with these laws and regulations. Cleanup and Solid Waste: Consumers expects to incur remediation and other response activity costs at a number of sites under the NREPA. Consumers believes that these costs should be recoverable in rates, but cannot guarantee that outcome. Consumers estimates that its liability for NREPA sites for which it can estimate a range of loss will be between $3 million and $4 million. At June 30, 2018, Consumers had a recorded liability of $3 million, the minimum amount in the range of its estimated probable NREPA liability, as no amount in the range was considered a better estimate than any other amount. Consumers is a potentially responsible party at a number of contaminated sites administered under CERCLA. CERCLA liability is joint and several. In 2010, Consumers received official notification from the EPA that identified Consumers as a potentially responsible party for cleanup of PCBs at the Kalamazoo River CERCLA site. The notification claimed that the EPA has reason to believe that Consumers disposed of PCBs and arranged for the disposal and treatment of PCB-containing materials at portions of the site. In 2011, Consumers received a follow-up letter from the EPA requesting that Consumers agree to participate in a removal action plan along with several other companies for an area of lower Portage Creek, which is connected to the Kalamazoo River. All parties, including Consumers, that were asked to participate in the removal action plan declined to accept liability. Until further information is received from the EPA, Consumers is unable to estimate a range of potential liability for cleanup of the river. Based on its experience, Consumers estimates that its share of the total liability for known CERCLA sites will be between $3 million and $8 million. Various factors, including the number and creditworthiness of potentially responsible parties involved with each site, affect Consumers’ share of the total liability. At June 30, 2018, Consumers had a recorded liability of $3 million for its share of the total liability at these sites, the minimum amount in the range of its estimated probable CERCLA liability, as no amount in the range was considered a better estimate than any other amount. The timing of payments related to Consumers’ remediation and other response activities at its CERCLA and NREPA sites is uncertain. Consumers periodically reviews these cost estimates. A change in the underlying assumptions, such as an increase in the number of sites, different remediation techniques, the nature and extent of contamination, and legal and regulatory requirements, could affect its estimates of NREPA and CERCLA liability. Ludington PCB: In 1998, during routine maintenance activities, Consumers identified PCB as a component in certain paint, grout, and sealant materials at Ludington. Consumers removed part of the PCB material and replaced it with non‑PCB material. Consumers has had several communications with the EPA regarding this matter, but cannot predict the financial impact or outcome. MCV PPA: In December 2017, the MCV Partnership initiated arbitration against Consumers, asserting a breach of contract associated with the MCV PPA. Under this PPA, Consumers pays the MCV Partnership a fixed energy charge based on Consumers’ annual average baseload coal generating plant operating and maintenance cost, fuel inventory, and administrative and general expenses. The MCV Partnership asserts that Consumers should have installed pollution control equipment on coal-fueled electric generating units years before they were retired. The MCV Partnership also asserts that Consumers should have installed pollution control equipment earlier on its remaining coal-fueled electric generating units. The assertion claims that these changes would have increased Consumers’ costs to operate and maintain the facilities and, thereby, the fixed energy charge paid to the MCV Partnership. Additionally, the MCV Partnership claims that Consumers improperly characterized certain costs included in the calculation of the fixed energy charge. The claim estimates damages and interest in excess of $270 million, the majority of which is related to the claim on the installation of pollution control equipment. Consumers believes that the MCV Partnership’s claim is without merit, but cannot predict the financial impact or outcome of the matter. Underwater Cables in Straits of Mackinac: Consumers owns certain underwater electric cables in the Straits of Mackinac, which were de‑energized and retired in 1990. Consumers was notified that some of these cables were damaged as a result of vessel activity in April 2018. Following the notification, Consumers located, inspected, sampled, capped, and returned the retired cables to their original location on the lake bottom, and did not find any substantive evidence of environmental contamination. Consumers is collaborating with the State of Michigan, local tribes, and other stakeholders to evaluate the status of the cables and to determine if any additional action is required. Consumers cannot predict the outcome of this matter, but if Consumers is required to remove all the cables, it could incur additional costs of up to $10 million. Consumers plans to file suit against the company that owns the vessel that allegedly caused the damage. Consumers would likely seek recovery from customers of any costs incurred. Consumers Gas Utility Contingencies Gas Environmental Matters: Consumers expects to incur remediation and other response activity costs at a number of sites under the NREPA. These sites include 23 former MGP facilities. Consumers operated the facilities on these sites for some part of their operating lives. For some of these sites, Consumers has no present ownership interest or may own only a portion of the original site. At June 30, 2018, Consumers had a recorded liability of $83 million for its remaining obligations for these sites. This amount represents the present value of long-term projected costs, using a discount rate of 2.57 percent and an inflation rate of 2.5 percent. The undiscounted amount of the remaining obligation is $90 million. Consumers expects to pay the following amounts for remediation and other response activity costs during the remainder of 2018 and in each of the next five years:
In Millions |
| 2018 |  | 2019 |  | 2020 |  | 2021 |  | 2022 |  | 2023 |
Consumers |  |  |  |  |  |  |  |  |  |  |  |
Remediation and other response activity costs |  | $ | 11 |  |  | $ | 18 |  |  | $ | 10 |  |  | $ | 18 |  |  | $ | 7 |  |  | $ | 2 |
Consumers periodically reviews these cost estimates. Any significant change in the underlying assumptions, such as an increase in the number of sites, changes in remediation techniques, or legal and regulatory requirements, could affect Consumers’ estimates of annual response activity costs and the MGP liability. Pursuant to orders issued by the MPSC, Consumers defers its MGP-related remediation costs and recovers them from its customers over a ten-year period. At June 30, 2018, Consumers had a regulatory asset of $139 million related to the MGP sites. Consumers estimates that its liability to perform remediation and other response activities at NREPA sites other than the MGP sites could reach $3 million. At June 30, 2018, Consumers had a recorded liability of less than $1 million, the minimum amount in the range of its estimated probable liability, as no amount in the range was considered a better estimate than any other amount. Guarantees Presented in the following table are CMS Energy’s and Consumers’ guarantees at June 30, 2018:
In Millions |
Guarantee Description | Issue Date | Expiration Date | Maximum Obligation |  | Carrying Amount |
CMS Energy, including Consumers |  |  |  |  |  |  |  |
Indemnity obligations from stock and asset sale agreements 1 |  | Various |  | Indefinite |  | $ | 153 |  |  | $ | 3 |
Guarantees 2 |  | Various |  | Indefinite |  | 39 |  |  | — |
Consumers |  |  |  |  |  |  |  |
Guarantee 2 |  | July 2011 |  | Indefinite |  | $ | 30 |  |  | $ | — |
1 | These obligations arose from stock and asset sale agreements under which CMS Energy or a subsidiary of CMS Energy indemnified the purchaser for losses resulting from various matters, primarily claims related to taxes. CMS Energy believes the likelihood of material loss to be remote for the indemnity obligations not recorded as liabilities.
2 | At Consumers, this obligation comprises a guarantee provided to the U.S. Department of Energy in connection with a settlement agreement regarding damages resulting from the department’s failure to accept spent nuclear fuel from nuclear power plants formerly owned by Consumers. At CMS Energy, the guarantee obligations comprise Consumers’ guarantee to the U.S. Department of Energy and CMS Energy’s 1994 guarantee of non‑recourse revenue bonds issued by Genesee.
Additionally, in the normal course of business, CMS Energy, Consumers, and certain other subsidiaries of CMS Energy have entered into various agreements containing tax and other indemnity provisions for which they are unable to estimate the maximum potential obligation. The carrying value of these indemnity obligations is $1 million. CMS Energy and Consumers consider the likelihood that they would be required to perform or incur substantial losses related to these indemnities to be remote. Other Contingencies In addition to the matters disclosed in this Note and Note 2, Regulatory Matters, there are certain other lawsuits and administrative proceedings before various courts and governmental agencies arising in the ordinary course of business to which CMS Energy, Consumers, and certain other subsidiaries of CMS Energy are parties. These other lawsuits and proceedings may involve personal injury, property damage, contracts, environmental matters, federal and state taxes, rates, licensing, employment, and other matters. Further, CMS Energy and Consumers occasionally self-report certain regulatory non‑compliance matters that may or may not eventually result in administrative proceedings. CMS Energy and Consumers believe that the outcome of any one of these proceedings will not have a material negative effect on their consolidated results of operations, financial condition, or liquidity.
Consumers Energy Company |
Site Contingency [Line Items] |
Contingencies and Commitments | Contingencies and Commitments CMS Energy and Consumers are involved in various matters that give rise to contingent liabilities. Depending on the specific issues, the resolution of these contingencies could negatively affect CMS Energy’s and Consumers’ liquidity, financial condition, and results of operations. In their disclosures of these matters, CMS Energy and Consumers provide an estimate of the possible loss or range of loss when such an estimate can be made. Disclosures that state that CMS Energy or Consumers cannot predict the outcome of a matter indicate that they are unable to estimate a possible loss or range of loss for the matter. CMS Energy Contingencies Gas Index Price Reporting Litigation: CMS Energy, along with CMS MST, CMS Field Services, Cantera Natural Gas, Inc., and Cantera Gas Company, were named as defendants in four class action lawsuits and one individual lawsuit arising as a result of alleged inaccurate natural gas price reporting to publications that report trade information. Allegations include price-fixing conspiracies, restraint of trade, and artificial inflation of natural gas retail prices in Kansas, Missouri, and Wisconsin. In 2016, CMS Energy entities reached a settlement with the plaintiffs in the Kansas and Missouri class action cases for an amount that was not material to CMS Energy. In August 2017, the federal district court approved the settlement. Plaintiffs are making claims for the following: treble damages, full consideration damages, exemplary damages, costs, interest, and/or attorneys’ fees. After removal to federal court, all of the cases were transferred to a single federal district court pursuant to the multidistrict litigation process. In 2010 and 2011, all claims against CMS Energy defendants were dismissed by the district court based on FERC preemption. In 2013, the U.S. Court of Appeals for the Ninth Circuit reversed the district court decision. The appellate court found that FERC preemption does not apply under the facts of these cases. The appellate court affirmed the district court’s denial of leave to amend to add federal antitrust claims. The matter was appealed to the U.S. Supreme Court, which in 2015 upheld the Ninth Circuit’s decision. The cases were remanded back to the federal district court. In 2016, the federal district court granted the defendants’ motion for summary judgment in the individual lawsuit filed in Kansas based on a release in a prior settlement involving similar allegations; the order of summary judgment was subsequently appealed. In March 2018, the U.S. Court of Appeals for the Ninth Circuit reversed the lower court’s ruling and remanded the case back to the federal district court. In March 2017, the federal district court denied plaintiffs’ motion for class certification in the two pending class action cases. The plaintiffs appealed that decision to the U.S. Court of Appeals for the Ninth Circuit, which has accepted the matter for hearing. In June 2017, an unaffiliated company that is also a defendant in these cases filed for bankruptcy, which could increase the risk of loss to CMS Energy. These cases involve complex facts, a large number of similarly situated defendants with different factual positions, and multiple jurisdictions. Presently, any estimate of liability would be highly speculative; the amount of CMS Energy’s reasonably possible loss would be based on widely varying models previously untested in this context. If the outcome after appeals is unfavorable, these cases could negatively affect CMS Energy’s liquidity, financial condition, and results of operations. Bay Harbor: CMS Land retained environmental remediation obligations for the collection and treatment of leachate, a liquid consisting of water and other substances, at Bay Harbor after selling its interests in the development in 2002. Leachate is produced when water enters into cement kiln dust piles left over from former cement plant operations at the site. In 2012, CMS Land and the MDEQ finalized an agreement that established the final remedies and the future water quality criteria at the site. CMS Land completed all construction necessary to implement the remedies required by the agreement and will continue to maintain and operate a system to discharge treated leachate into Little Traverse Bay under an NPDES permit issued in 2010 and renewed in 2016. The renewed NPDES permit is valid through September 2020. Various claims have been brought against CMS Land or its affiliates, including CMS Energy, alleging environmental damage to property, loss of property value, insufficient disclosure of environmental matters, breach of agreement relating to access, or other matters. CMS Land and other parties have received a demand for payment from the EPA in the amount of $8 million, plus interest and costs. The EPA is seeking recovery under CERCLA of response costs allegedly incurred at Bay Harbor. These costs exceed what was agreed to in a 2005 order between CMS Land and the EPA and CMS Land believes that the claim was made beyond the appropriate statute of limitations. CMS Land has communicated to the EPA that it does not believe that this is a valid claim. The EPA has filed a lawsuit to collect these costs. At June 30, 2018, CMS Energy had a recorded liability of $47 million for its remaining obligations for environmental remediation. CMS Energy calculated this liability based on discounted projected costs, using a discount rate of 4.34 percent and an inflation rate of one percent on annual operating and maintenance costs. The undiscounted amount of the remaining obligation is $58 million. CMS Energy expects to pay the following amounts for long-term liquid disposal and operating and maintenance costs during the remainder of 2018 and in each of the next five years:
In Millions |
| 2018 |  | 2019 |  | 2020 |  | 2021 |  | 2022 |  | 2023 |
CMS Energy |  |  |  |  |  |  |  |  |  |  |  |
Long-term liquid disposal and operating and maintenance costs |  | $ | 2 |  |  | $ | 4 |  |  | $ | 4 |  |  | $ | 4 |  |  | $ | 4 |  |  | $ | 4 |
CMS Energy’s estimate of response activity costs and the timing of expenditures could change if there are changes in circumstances or assumptions used in calculating the liability. Although a liability for its present estimate of remaining response activity costs has been recorded, CMS Energy cannot predict the ultimate financial impact or outcome of this matter. Equatorial Guinea Tax Claim: In 2002, CMS Energy sold its oil, gas, and methanol investments in Equatorial Guinea. The government of Equatorial Guinea claims that, in connection with the sale, CMS Energy owes $152 million in taxes, plus substantial penalties and interest that could be up to the amount of the taxes claimed. In 2015, the matter was proceeding to formal arbitration; however, since then, the government of Equatorial Guinea has stopped communicating. CMS Energy has concluded that the government’s tax claim is without merit and will continue to contest the claim, but cannot predict the financial impact or outcome of the matter. An unfavorable outcome could have a material adverse effect on CMS Energy’s liquidity, financial condition, and results of operations. Consumers Electric Utility Contingencies Electric Environmental Matters: Consumers’ operations are subject to environmental laws and regulations. Historically, Consumers has generally been able to recover, in customer rates, the costs to operate its facilities in compliance with these laws and regulations. Cleanup and Solid Waste: Consumers expects to incur remediation and other response activity costs at a number of sites under the NREPA. Consumers believes that these costs should be recoverable in rates, but cannot guarantee that outcome. Consumers estimates that its liability for NREPA sites for which it can estimate a range of loss will be between $3 million and $4 million. At June 30, 2018, Consumers had a recorded liability of $3 million, the minimum amount in the range of its estimated probable NREPA liability, as no amount in the range was considered a better estimate than any other amount. Consumers is a potentially responsible party at a number of contaminated sites administered under CERCLA. CERCLA liability is joint and several. In 2010, Consumers received official notification from the EPA that identified Consumers as a potentially responsible party for cleanup of PCBs at the Kalamazoo River CERCLA site. The notification claimed that the EPA has reason to believe that Consumers disposed of PCBs and arranged for the disposal and treatment of PCB-containing materials at portions of the site. In 2011, Consumers received a follow-up letter from the EPA requesting that Consumers agree to participate in a removal action plan along with several other companies for an area of lower Portage Creek, which is connected to the Kalamazoo River. All parties, including Consumers, that were asked to participate in the removal action plan declined to accept liability. Until further information is received from the EPA, Consumers is unable to estimate a range of potential liability for cleanup of the river. Based on its experience, Consumers estimates that its share of the total liability for known CERCLA sites will be between $3 million and $8 million. Various factors, including the number and creditworthiness of potentially responsible parties involved with each site, affect Consumers’ share of the total liability. At June 30, 2018, Consumers had a recorded liability of $3 million for its share of the total liability at these sites, the minimum amount in the range of its estimated probable CERCLA liability, as no amount in the range was considered a better estimate than any other amount. The timing of payments related to Consumers’ remediation and other response activities at its CERCLA and NREPA sites is uncertain. Consumers periodically reviews these cost estimates. A change in the underlying assumptions, such as an increase in the number of sites, different remediation techniques, the nature and extent of contamination, and legal and regulatory requirements, could affect its estimates of NREPA and CERCLA liability. Ludington PCB: In 1998, during routine maintenance activities, Consumers identified PCB as a component in certain paint, grout, and sealant materials at Ludington. Consumers removed part of the PCB material and replaced it with non‑PCB material. Consumers has had several communications with the EPA regarding this matter, but cannot predict the financial impact or outcome. MCV PPA: In December 2017, the MCV Partnership initiated arbitration against Consumers, asserting a breach of contract associated with the MCV PPA. Under this PPA, Consumers pays the MCV Partnership a fixed energy charge based on Consumers’ annual average baseload coal generating plant operating and maintenance cost, fuel inventory, and administrative and general expenses. The MCV Partnership asserts that Consumers should have installed pollution control equipment on coal-fueled electric generating units years before they were retired. The MCV Partnership also asserts that Consumers should have installed pollution control equipment earlier on its remaining coal-fueled electric generating units. The assertion claims that these changes would have increased Consumers’ costs to operate and maintain the facilities and, thereby, the fixed energy charge paid to the MCV Partnership. Additionally, the MCV Partnership claims that Consumers improperly characterized certain costs included in the calculation of the fixed energy charge. The claim estimates damages and interest in excess of $270 million, the majority of which is related to the claim on the installation of pollution control equipment. Consumers believes that the MCV Partnership’s claim is without merit, but cannot predict the financial impact or outcome of the matter. Underwater Cables in Straits of Mackinac: Consumers owns certain underwater electric cables in the Straits of Mackinac, which were de‑energized and retired in 1990. Consumers was notified that some of these cables were damaged as a result of vessel activity in April 2018. Following the notification, Consumers located, inspected, sampled, capped, and returned the retired cables to their original location on the lake bottom, and did not find any substantive evidence of environmental contamination. Consumers is collaborating with the State of Michigan, local tribes, and other stakeholders to evaluate the status of the cables and to determine if any additional action is required. Consumers cannot predict the outcome of this matter, but if Consumers is required to remove all the cables, it could incur additional costs of up to $10 million. Consumers plans to file suit against the company that owns the vessel that allegedly caused the damage. Consumers would likely seek recovery from customers of any costs incurred. Consumers Gas Utility Contingencies Gas Environmental Matters: Consumers expects to incur remediation and other response activity costs at a number of sites under the NREPA. These sites include 23 former MGP facilities. Consumers operated the facilities on these sites for some part of their operating lives. For some of these sites, Consumers has no present ownership interest or may own only a portion of the original site. At June 30, 2018, Consumers had a recorded liability of $83 million for its remaining obligations for these sites. This amount represents the present value of long-term projected costs, using a discount rate of 2.57 percent and an inflation rate of 2.5 percent. The undiscounted amount of the remaining obligation is $90 million. Consumers expects to pay the following amounts for remediation and other response activity costs during the remainder of 2018 and in each of the next five years:
In Millions |
| 2018 |  | 2019 |  | 2020 |  | 2021 |  | 2022 |  | 2023 |
Consumers |  |  |  |  |  |  |  |  |  |  |  |
Remediation and other response activity costs |  | $ | 11 |  |  | $ | 18 |  |  | $ | 10 |  |  | $ | 18 |  |  | $ | 7 |  |  | $ | 2 |
Consumers periodically reviews these cost estimates. Any significant change in the underlying assumptions, such as an increase in the number of sites, changes in remediation techniques, or legal and regulatory requirements, could affect Consumers’ estimates of annual response activity costs and the MGP liability. Pursuant to orders issued by the MPSC, Consumers defers its MGP-related remediation costs and recovers them from its customers over a ten-year period. At June 30, 2018, Consumers had a regulatory asset of $139 million related to the MGP sites. Consumers estimates that its liability to perform remediation and other response activities at NREPA sites other than the MGP sites could reach $3 million. At June 30, 2018, Consumers had a recorded liability of less than $1 million, the minimum amount in the range of its estimated probable liability, as no amount in the range was considered a better estimate than any other amount. Guarantees Presented in the following table are CMS Energy’s and Consumers’ guarantees at June 30, 2018:
In Millions |
Guarantee Description | Issue Date | Expiration Date | Maximum Obligation |  | Carrying Amount |
CMS Energy, including Consumers |  |  |  |  |  |  |  |
Indemnity obligations from stock and asset sale agreements 1 |  | Various |  | Indefinite |  | $ | 153 |  |  | $ | 3 |
Guarantees 2 |  | Various |  | Indefinite |  | 39 |  |  | — |
Consumers |  |  |  |  |  |  |  |
Guarantee 2 |  | July 2011 |  | Indefinite |  | $ | 30 |  |  | $ | — |
1 | These obligations arose from stock and asset sale agreements under which CMS Energy or a subsidiary of CMS Energy indemnified the purchaser for losses resulting from various matters, primarily claims related to taxes. CMS Energy believes the likelihood of material loss to be remote for the indemnity obligations not recorded as liabilities.
2 | At Consumers, this obligation comprises a guarantee provided to the U.S. Department of Energy in connection with a settlement agreement regarding damages resulting from the department’s failure to accept spent nuclear fuel from nuclear power plants formerly owned by Consumers. At CMS Energy, the guarantee obligations comprise Consumers’ guarantee to the U.S. Department of Energy and CMS Energy’s 1994 guarantee of non‑recourse revenue bonds issued by Genesee.
Additionally, in the normal course of business, CMS Energy, Consumers, and certain other subsidiaries of CMS Energy have entered into various agreements containing tax and other indemnity provisions for which they are unable to estimate the maximum potential obligation. The carrying value of these indemnity obligations is $1 million. CMS Energy and Consumers consider the likelihood that they would be required to perform or incur substantial losses related to these indemnities to be remote. Other Contingencies In addition to the matters disclosed in this Note and Note 2, Regulatory Matters, there are certain other lawsuits and administrative proceedings before various courts and governmental agencies arising in the ordinary course of business to which CMS Energy, Consumers, and certain other subsidiaries of CMS Energy are parties. These other lawsuits and proceedings may involve personal injury, property damage, contracts, environmental matters, federal and state taxes, rates, licensing, employment, and other matters. Further, CMS Energy and Consumers occasionally self-report certain regulatory non‑compliance matters that may or may not eventually result in administrative proceedings. CMS Energy and Consumers believe that the outcome of any one of these proceedings will not have a material negative effect on their consolidated results of operations, financial condition, or liquidity.

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