The Company has operating and capital leases, mainly for locomotives, freight cars and intermodal equipment. Of the capital leases, many provide the option to purchase the leased items at fixed values during or at the end of the lease term. As at December 31, 2011, the Company's commitments under these operating and capital leases were $665 million and $1,254 million, respectively. Minimum rental payments for operating leases having initial non-cancelable lease terms of more than one year and minimum lease payments for capital leases in each of the next five years and thereafter are as follows:

In millions		Operating		Capital

2012	$	128	$	99
2013		103		151
2014		76		270
2015		61		109
2016		45		297
2017 and thereafter		252		328
	$	665		1,254
Less: imputed interest on capital leases at rates ranging from approximately 0.7% to 11.8%				299
Present value of minimum lease payments included in debt			$	955

The Company also has operating lease agreements for its automotive fleet with one-year non-cancelable terms for which its practice is to renew monthly thereafter. The estimated annual rental payments for such leases are approximately $30 million and generally extend over five years.

Rent expense for all operating leases was $143 million, $176 million and $213 million for the years ended December 31, 2011, 2010 and 2009, respectively. Contingent rentals and sublease rentals were not significant.

As at December 31, 2011, the Company had commitments to acquire railroad ties, rail, freight cars, locomotives, and other equipment and services, as well as outstanding information technology service contracts and licenses, at an aggregate cost of $727 million ($740 million as at December 31, 2010). The Company also has remaining estimated commitments in relation to the acquisition of the principal lines of the former Elgin, Joliet and Eastern Railway Company of approximately $130 million to be spent over the next few years for railroad infrastructure improvements, grade separation projects, as well as commitments under a series of agreements with individual communities and a comprehensive voluntary mitigation program established to address surrounding municipalities' concerns. The commitment for the grade separation projects is based on estimated costs provided by the STB at the time of acquisition and could be subject to adjustment. In addition, remaining implementation costs associated with the U.S. federal government legislative requirement to implement positive train control (PTC) by 2015 are estimated to be approximately $193 million (US$190 million). The Company also has agreements with fuel suppliers to purchase approximately 61% of its estimated 2012 volume, 41% of its anticipated 2013 volume and 11% of its anticipated 2014 volume at market prices prevailing on the date of the purchase.

In the normal course of business, the Company becomes involved in various legal actions seeking compensatory and occasionally punitive damages, including actions brought on behalf of various purported classes of claimants and claims relating to employee and third-party personal injuries, occupational disease and property damage, arising out of harm to individuals or property allegedly caused by, but not limited to, derailments or other accidents.

Employee injuries are governed by the workers' compensation legislation in each province whereby employees may be awarded either a lump sum or future stream of payments depending on the nature and severity of the injury. As such, the provision for employee injury claims is discounted. In the provinces where the Company is self-insured, costs related to employee work-related injuries are accounted for based on actuarially developed estimates of the ultimate cost associated with such injuries, including compensation, health care and third-party administration costs. A comprehensive actuarial study is generally performed at least on a triennial basis. For all other legal actions, the Company maintains, and regularly updates on a case-by-case basis, provisions for such items when the expected loss is both probable and can be reasonably estimated based on currently available information.

As at December 31, 2011, 2010 and 2009, the Company's provision for personal injury and other claims in Canada was as follows:

In millions		2011		2010		2009
Balance January 1	$	200	$	178	$	189
Accruals and other		31		59		48
Payments		(32)		(37)		(59)
Balance December 31	$	199	$	200	$	178

Current portion - Balance December 31	$	39	$	39	$	34

Personal injury claims by the Company's employees, including claims alleging occupational disease and work-related injuries, are subject to the provisions of the Federal Employers' Liability Act (FELA). Employees are compensated under FELA for damages assessed based on a finding of fault through the U.S. jury system or through individual settlements. As such, the provision is undiscounted. With limited exceptions where claims are evaluated on a case-by-case basis, the Company follows an actuarial-based approach and accrues the expected cost for personal injury, including asserted and unasserted occupational disease claims, and property damage claims, based on actuarial estimates of their ultimate cost. A comprehensive actuarial study is performed annually.

For employee work-related injuries, including asserted occupational disease claims, and third-party claims, including grade crossing, trespasser and property damage claims, the actuarial valuation considers, among other factors, CN's historical patterns of claims filings and payments. For unasserted occupational disease claims, the actuarial study includes the projection of CN's experience into the future considering the potentially exposed population. The Company adjusts its liability based upon management's assessment and the results of the study. On an ongoing basis, management reviews and compares the assumptions inherent in the latest actuarial study with the current claim experience and, if required, adjustments to the liability are recorded.

Due to the inherent uncertainty involved in projecting future events, including events related to occupational diseases, which include but are not limited to, the timing and number of actual claims, the average cost per claim and the legislative and judicial environment, the Company's future payments may differ from current amounts recorded.

External actuarial studies reflecting favorable claims development over recent years have supported net reductions to the Company's provision for U.S. personal injury and other claims of $6 million, $19 million and $60 million in 2011, 2010 and 2009, respectively. The reductions were mainly attributable to decreases in the Company's estimates of unasserted claims and costs related to asserted claims as a result of its ongoing risk mitigation strategy focused on reducing the frequency and severity of claims through injury prevention and containment; mitigation of claims; and lower settlements for existing claims.

As at December 31, 2011, 2010 and 2009, the Company's provision for personal injury and other claims in the U.S. was as follows:

In millions		2011		2010		2009
Balance January 1	$	146	$	166	$	265
Accruals and other		30		7		(46)
Payments		(65)		(27)		(53)
Balance December 31	$	111	$	146	$	166

Current portion - Balance December 31	$	45	$	44	$	72

Although the Company considers such provisions to be adequate for all its outstanding and pending claims, the final outcome with respect to actions outstanding or pending at December 31, 2011, or with respect to future claims, cannot be reasonably determined. When establishing provisions for contingent litigation, the Company considers, where a probable loss estimate cannot be made with reasonable certainty, a range of potential probable losses for each such matter, and records the amount it considers the most reasonable estimate within the range. However, when no amount within the range is a better estimate than any other amount, the minimum amount in the range is accrued. For matters where a loss is reasonably possible but not probable, a range of potential losses could not be estimated due to various factors which may include the limited availability of facts, the lack of demand for specific damages and the fact that proceedings were at an early stage. Based on information currently available, the Company believes that the eventual outcome of the actions against the Company will not, individually or in the aggregate, have a material adverse effect on the Company's consolidated financial position. However, due to the inherent inability to predict with certainty unforeseeable future developments, there can be no assurance that the ultimate resolution of these actions will not have a material adverse effect on the Company's results of operations, financial position or liquidity in a particular quarter or fiscal year.

The Company's operations are subject to numerous federal, provincial, state, municipal and local environmental laws and regulations in Canada and the United States concerning, among other things, emissions into the air; discharges into waters; the generation, handling, storage, transportation, treatment and disposal of waste, hazardous substances, and other materials; decommissioning of underground and aboveground storage tanks; and soil and groundwater contamination. A risk of environmental liability is inherent in railroad and related transportation operations; real estate ownership, operation or control; and other commercial activities of the Company with respect to both current and past operations.

The Company has identified approximately 310 sites at which it is or may be liable for remediation costs, in some cases along with other potentially responsible parties, associated with alleged contamination and is subject to environmental clean-up and enforcement actions, including those imposed by the United States Federal Comprehensive Environmental Response, Compensation and Liability Act of 1980 (CERCLA), also known as the Superfund law, or analogous state laws. CERCLA and similar state laws, in addition to other similar Canadian and U.S. laws, generally impose joint and several liability for clean-up and enforcement costs on current and former owners and operators of a site, as well as those whose waste is disposed of at the site, without regard to fault or the legality of the original conduct. The Company has been notified that it is a potentially responsible party for study and clean-up costs at approximately 10 sites governed by the Superfund law (and analogous state laws) for which investigation and remediation payments are or will be made or are yet to be determined and, in many instances, is one of several potentially responsible parties.

The ultimate cost of addressing these known contaminated sites cannot be definitely established given that the estimated environmental liability for any given site may vary depending on the nature and extent of the contamination; the nature of anticipated response actions, taking into account the available clean-up techniques; evolving regulatory standards governing environmental liability; and the number of potentially responsible parties and their financial viability. As a result, liabilities are recorded based on the results of a four-phase assessment conducted on a site-by-site basis. A liability is initially recorded when environmental assessments occur, remedial efforts are probable, and when the costs, based on a specific plan of action in terms of the technology to be used and the extent of the corrective action required, can be reasonably estimated. The Company estimates the costs related to a particular site using cost scenarios established by external consultants based on the extent of contamination and expected costs for remedial efforts. In the case of multiple parties, the Company accrues its allocable share of liability taking into account the Company's alleged responsibility, the number of potentially responsible parties and their ability to pay their respective share of the liability. Adjustments to initial estimates are recorded as additional information becomes available.

The Company's provision for specific environmental sites is undiscounted and includes costs for remediation and restoration of sites, as well as monitoring costs. Environmental accruals, which are classified as Casualty and other in the Consolidated Statement of Income, include amounts for newly identified sites or contaminants as well as adjustments to initial estimates. Recoveries of environmental remediation costs from other parties are recorded as assets when their receipt is deemed probable.

As at December 31, 2011, 2010 and 2009, the Company's provision for specific environmental sites was as follows:

In millions			2011		2010		2009
Balance January 1		$	150	$	103	$	125
	Accruals and other		17		67		(7)
	Payments		(15)		(20)		(15)
Balance December 31		$	152	$	150	$	103

Current portion - Balance December 31		$	63	$	34	$	38

The Company anticipates that the majority of the liability at December 31, 2011 will be paid out over the next five years. However, some costs may be paid out over a longer period. The Company expects to partly recover certain accrued remediation costs associated with alleged contamination and has recorded a receivable in Intangible and other assets for such recoverable amounts. Based on the information currently available, the Company considers its provisions to be adequate.

While the Company believes that it has identified the costs likely to be incurred for environmental matters in the next several years based on known information, the discovery of new facts, future changes in laws, the possibility of releases of hazardous materials into the environment and the Company's ongoing efforts to identify potential environmental liabilities that may be associated with its properties may result in the identification of additional environmental liabilities and related costs. The magnitude of such additional liabilities and the costs of complying with future environmental laws and containing or remediating contamination cannot be reasonably estimated due to many factors, including:

(i) the lack of specific technical information available with respect to many sites;

(ii) the absence of any government authority, third-party orders, or claims with respect to particular sites;

(iii) the potential for new or changed laws and regulations and for development of new remediation technologies and uncertainty regarding the timing of the work with respect to particular sites; and

(iv) the determination of the Company's liability in proportion to other potentially responsible parties and the ability to recover costs from any third parties with respect to particular sites.

Therefore, the likelihood of any such costs being incurred or whether such costs would be material to the Company cannot be determined at this time. There can thus be no assurance that liabilities or costs related to environmental matters will not be incurred in the future, or will not have a material adverse effect on the Company's financial position or results of operations in a particular quarter or fiscal year, or that the Company's liquidity will not be adversely impacted by such liabilities or costs, although management believes, based on current information, that the costs to address environmental matters will not have a material adverse effect on the Company's financial position or liquidity. Costs related to any unknown existing or future contamination will be accrued in the period in which they become probable and reasonably estimable.

In railroad and related transportation operations, it is possible that derailments or other accidents, including spills and releases of hazardous materials, may occur that could cause harm to human health or to the environment. As a result, the Company may incur costs in the future, which may be material, to address any such harm, compliance with laws and other risks, including costs relating to the performance of clean-ups, payment of environmental penalties and remediation obligations, and damages relating to harm to individuals or property.

The Company may incur significant capital and operating costs associated with environmental regulatory compliance and clean-up requirements, in its railroad operations and relating to its past and present ownership, operation or control of real property. Operating expenses for environmental matters amounted to $4 million in 2011, $23 million in 2010 and $11 million in 2009. In addition based on the results of its operations and maintenance programs, as well as ongoing environmental audits and other factors, the Company plans for specific capital improvements on an annual basis. Certain of these improvements help ensure facilities, such as fuelling stations and waste water and storm water treatment systems, comply with environmental standards and include new construction and the updating of existing systems and/or processes. Other capital expenditures relate to assessing and remediating certain impaired properties. The Company's environmental capital expenditures amounted to $11 million in 2011, $14 million in 2010 and $9 million in 2009.

In the normal course of business, the Company, including certain of its subsidiaries, enters into agreements that may involve providing guarantees or indemnifications to third parties and others, which may extend beyond the term of the agreements. These include, but are not limited to, residual value guarantees on operating leases, standby letters of credit and surety and other bonds, and indemnifications that are customary for the type of transaction or for the railway business.

The Company is required to recognize a liability for the fair value of the obligation undertaken in issuing certain guarantees on the date the guarantee is issued or modified. In addition, where the Company expects to make a payment in respect of a guarantee, a liability will be recognized to the extent that one has not yet been recognized.

The Company has guaranteed a portion of the residual values of certain of its assets under operating leases with expiry dates between 2012 and 2022, for the benefit of the lessor. If the fair value of the assets, at the end of their respective lease term, is less than the fair value, as estimated at the inception of the lease, then the Company must, under certain conditions, compensate the lessor for the shortfall. At December 31, 2011, the maximum exposure in respect of these guarantees was $112 million. There are no recourse provisions to recover any amounts from third parties.

As at December 31, 2011, the Company, including certain of its subsidiaries, has granted $499 million of irrevocable standby letters of credit and $10 million of surety and other bonds, issued by highly rated financial institutions, to third parties to indemnify them in the event the Company does not perform its contractual obligations. As at December 31, 2011, the maximum potential liability under these guarantee instruments was $509 million, of which $439 million related to workers' compensation and other employee benefit liabilities and $70 million related to equipment under leases and other liabilities. The letters of credit were drawn on the Company's bilateral letter of credit facilities. The Company has not recorded a liability in respect of these guarantee instruments as they relate to the Company's future performance. In addition, as the Company does not expect to make any payments under these guarantee instruments, the Company has not recorded an additional liability at December 31, 2011 with respect to such guarantees as they relate to the Company's future performance. The majority of the guarantee instruments mature at various dates between 2012 and 2014.

In the normal course of business, the Company has provided indemnifications, customary for the type of transaction or for the railway business, in various agreements with third parties, including indemnification provisions where the Company would be required to indemnify third parties and others. Indemnifications are found in various types of contracts with third parties which include, but are not limited to:

To the extent of any actual claims under these agreements, the Company maintains provisions for such items, which it considers to be adequate. Due to the nature of the indemnification clauses, the maximum exposure for future payments may be material. However, such exposure cannot be reasonably determined.

During the year, the Company entered into various indemnification contracts with third parties for which the maximum exposure for future payments cannot be reasonably determined. As a result, the Company was unable to determine the fair value of these guarantees and accordingly, no liability was recorded. There are no recourse provisions to recover any amounts from third parties.