At December 31, 2011, the Company had two outstanding irrevocable standby letters of credit, including one for $15.0 million related to the Company's payment obligation under its insurance programs and another for approximately $2.2 million related to contract performance obligations. At December 31, 2010, the Company had one outstanding irrevocable standby letter of credit totaling $15.0 million related to the Company's payment obligation under its insurance programs.

The Company leases real estate, construction equipment and office equipment under operating leases with terms ranging from one to nine years. As of December 31, 2011, future minimum lease payments for these operating leases were as follows: $4.8 million for 2012, $2.2 million for 2013, $0.9 million for 2014, $0.4 million for 2015, $0.2 million for 2016 and $0.5 million thereafter.

At times, the Company has guaranteed the residual value of the underlying assets under certain equipment operating leases at the date of termination of such leases. For such guarantees, the Company agrees to pay any differences between this residual value and the fair market value of each underlying asset as of the lease termination date. As of December 31, 2010, the maximum guaranteed residual value of leased assets was approximately $0.6 million. The Company had no leases in effect at December 31, 2011 which included guaranteed residual values.

Rent expense includes lease payments as well as rent on items that are rented for less than one year. Total rent expense for the years ended December 31, 2011, 2010 and 2009, was $32.2 million, $31.4 million and $30.0 million, respectively.

As of December 31, 2011, the Company had approximately $6.0 million in outstanding purchase obligations for certain construction equipment, with most of the cash outlay scheduled to occur during the next six months.

The Company carries insurance policies, which are subject to certain deductibles, for workers' compensation, general liability, automobile liability and other coverages. The deductible for each line of coverage is between $1.0 million and $1.5 million per claim, depending on whether the claim aggregate has been met. Once a policy's claim aggregate is reached per line of coverage, the deductible for that policy is reduced to $1.0 million per claim.

Health insurance benefits are subject to a $0.1 million deductible for qualified individuals. Losses up to the stop loss amounts are accrued based upon the Company's estimates of the ultimate liability for claims reported and an estimate of claims incurred but not yet reported.

The insurance and claims accruals are based on known facts, actuarial estimates and historical trends. While recorded accruals are based on the ultimate liability, which includes amounts in excess of the stop loss deductible, a corresponding receivable for amounts in excess of the stop loss deductible is included in current assets in the consolidated balance sheets. The rollforward of activity in the insurance reserves was as follows for the years ended December 31:

(in thousands)	2011			2010

Balance at beginning of period	$	34,044		$	33,100
Net increases in reserves		23,621			14,234
Net payments made		(18,815	)		(13,290	)

Balance at end of period	$	38,850		$	34,044

Insurance expense, including premiums, for workers' compensation, general liability, automobile liability and employee health benefits for the years ended December 31, 2011, 2010 and 2009 was $21.5 million, $16.0 million and $17.4 million, respectively.

As of December 31, 2009, the Company had recorded a contingent termination payment liability of approximately $1.6 million related to the employment agreements it entered into with six executive officers in December 2007, which were amended in December 2008 (each an "Employment Agreement"). The liability recorded represented the amount the named executive officers would have been eligible to receive under the terms of the original Employment Agreements if they were to voluntarily terminate employment without "good reason" (as defined in the Employment Agreements) at any time.

In March 2010, the Company amended and restated the Employment Agreements, which, among other things, removed the provision for severance pay subject to a voluntary termination without good reason. The revised severance pay provisions in the Employment Agreements are all under the employer's control. Therefore, the Company eliminated the $1.6 million liability related to this severance provision as a result of the amendment. The benefit of reversing this liability was included as a reduction to selling, general and administrative expenses in the accompanying consolidated statement of operations for the year ended December 31, 2010.

In certain circumstances, the Company is required to provide performance bonds in connection with its future performance on contractual commitments. The Company has indemnified its sureties for any expenses paid out under these performance bonds. As of December 31, 2011, an aggregate of approximately $881.1 million in original face amount of bonds issued by the surety were outstanding. Our estimated remaining cost to complete these bonded projects was approximately $474.5 million as of December 31, 2011.

Many of the Company's subsidiaries' field labor employees are covered by collective bargaining agreements. The agreements require the subsidiaries to pay specified wages, provide certain benefits and contribute certain amounts to multi-employer pension plans. If a subsidiary withdraws from one or more multi-employer pension plans or if the plans were to otherwise become underfunded, the subsidiary could be assessed liabilities for additional contributions related to the underfunding of these plans. Although we have been informed that several of the multi-employer pension plans to which our subsidiaries contribute have been labeled with a "critical" status, we are not currently aware of any potential significant liabilities related to this issue. See footnote 15 for further information related to the Company's participation in multi-employer plans.

The Company is from time-to-time party to various lawsuits, claims, and other legal proceedings that arise in the ordinary course of business. These actions typically seek, among other things, compensation for alleged personal injury, breach of contract and/or property damages, punitive damages, civil penalties or other losses, or injunctive or declaratory relief. With respect to all such lawsuits, claims and proceedings, the Company records reserves when it is probable that a liability has been incurred and the amount of loss can be reasonably estimated. The Company does not believe that any of these proceedings, separately or in the aggregate, would be expected to have a material adverse effect on the Company's financial position, results of operation or cash flows.

The Company is routinely subject to other civil claims, litigation and arbitration, and regulatory investigations arising in the ordinary course of our present business as well as in respect of our divested businesses. Some of these claims and litigations include claims related to the Company's current services and operations, and asbestos-related claims concerning historic operations of a predecessor affiliate. The Company believes that it has strong defenses to these claims as well as adequate insurance coverage in the event any asbestos-related claim is not resolved in our favor. These claims have not had a material impact on the Company to date, and the Company believes that the likelihood that a future material adverse outcome will result from these claims is remote. However, if facts and circumstances change in the future, the Company cannot be certain that an adverse outcome of one or more of these claims would not have a material adverse effect on the Company's financial condition, results of operations or cash flows.