LANDFILL AND ENVIRONMENTAL COSTS

As of March 31, 2013, we owned or operated 191 active solid waste landfills with total available disposal capacity of approximately 4.8 billion in-place cubic yards. Additionally, we have post-closure responsibility for 128 closed landfills.

Accrued Landfill and Environmental Costs

A summary of landfill and environmental liabilities as of March 31, 2013 and December 31, 2012 follows:



	2013			2012
Final capping, closure and post-closure liabilities	$	1,053.4		$	1,052.4
Remediation	557.3			563.7
Total accrued landfill and environmental costs	1,610.7			1,616.1
Less: Current portion	(189.4		)	(195.5		)
Long-term portion	$	1,421.3		$	1,420.6

Final Capping, Closure and Post-Closure Costs

The following table summarizes the activity in our asset retirement obligation liabilities, which include liabilities for final capping, closure and post-closure, for the three months ended March 31:



	2013			2012
Asset retirement obligation liabilities, beginning of year	$	1,052.4		$	1,037.0
Non-cash additions	8.1			8.2
Acquisitions/divestitures and other adjustments	—			(2.5		)
Asset retirement obligation adjustments	0.4			4.6
Payments	(26.7		)	(11.8		)
Accretion expense	19.2			19.7
Asset retirement obligation liabilities, end of period	1,053.4			1,055.2
Less: Current portion	(107.7		)	(89.0		)
Long-term portion	$	945.7		$	966.2

Annually, in the fourth quarter, we review, and update as necessary, our estimates of asset retirement obligations. However, if there are significant changes in the facts and circumstances related to a site during the year, we will update our assumptions prospectively in the period that we know all the relevant facts and circumstances.

The fair value of assets that are legally restricted for purposes of collateralizing certain of our final capping, closure and post-closure obligations was $54.9 million and $54.8 million as of March 31, 2013 and December 31, 2012, respectively. Such assets are included in restricted cash and marketable securities in our consolidated balance sheets.

Landfill Operating Expenses

In the normal course of business, we incur various operating costs associated with environmental compliance. These costs include, among other things, leachate treatment and disposal, methane gas and groundwater monitoring and systems maintenance, interim cap maintenance, costs associated with the application of daily cover materials, and the legal and administrative costs of ongoing environmental compliance. These costs are expensed as cost of operations in the periods in which they are incurred.

Environmental Remediation Liabilities

We accrue for remediation costs when they become probable and can be reasonably estimated. When there is a range of reasonable estimates of the costs associated with remediation of a site, we use the amount within the range that constitutes our best estimate. If no amount within the range appears to be a better estimate than any other, we use the amount that is at the low end of the range. It is reasonably possible that we will need to adjust the liabilities recorded for remediation to reflect the effects of new or additional information, to the extent such information impacts the costs, timing or duration of the required actions. If we used the reasonably possible high ends of our ranges, our aggregate potential remediation liability at March 31, 2013 would be approximately $374 million higher than the amounts recorded. Future changes in our estimates of the cost, timing or duration of the required actions could have a material adverse effect on our consolidated financial position, results of operations and cash flows.

The following table summarizes the activity in our environmental remediation liabilities for the three months ended March 31:



	2013			2012
Remediation liabilities, beginning of year	$	563.7		$	543.7
Remediation adjustments	5.8			(8.5		)
Payments	(18.9		)	(13.6		)
Accretion expense (non-cash interest expense)	6.7			8.4
Remediation liabilities, end of period	557.3			530.0
Less: Current portion	(81.7		)	(93.6		)
Long-term portion	$	475.6		$	436.4

The following is a discussion of certain of our significant remediation matters:

Bridgeton Landfill. During 2012, we encountered environmental issues at our closed Bridgeton Landfill in Missouri, and recorded a charge of $74.1 million to manage the remediation area and monitor the site. As of March 31, 2012, the remediation liability for this site is $59.0 million. We believe the remaining reasonably possible range of loss for remediation costs is $45 million to $235 million.

Countywide Landfill. In September 2009, Republic Services of Ohio II, LLC entered into Final Findings and Orders with the Ohio Environmental Protection Agency that require us to implement a comprehensive operation and maintenance program to manage the remediation area at the Countywide Recycling and Disposal Facility. The remediation liability for this site recorded as of March 31, 2013 is $51.7 million, of which $4.5 million is expected to be paid during the next twelve months. We believe the remaining reasonably possible range of loss for remediation costs is $49 million to $70 million.

Congress Landfill. In August 2010, Congress Development Company agreed with the State of Illinois to have a Final Consent Order entered by the Circuit Court of Illinois, Cook County. Pursuant to the this order, we have agreed to continue to implement certain remedial activities at this site. The remediation liability for this site recorded as of March 31, 2013 is $83.7 million, of which $8.2 million is expected to be paid during the next twelve months. We believe the remaining reasonably possible range of loss for remediation costs is $53 million to $154 million.