Fair Value Measurements

3 Months Ended

Jun. 30, 2012

Fair Value Measurements

Fair Value Measurements

4.Fair Value Measurements

We measure fair value as the exchange price that would be received for an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. Fair value measurements are based on a three-tier hierarchy that prioritizes the inputs used to measure fair value. These tiers include: Level 1, defined as observable inputs such as quoted prices in active markets for identical assets and liabilities; Level 2, defined as observable inputs other than Level 1 prices such as quoted prices for similar assets or liabilities or prices quoted in inactive markets; and Level 3, defined as unobservable inputs that are significant to the fair value of the asset or liability, and for which little or no market data exists, therefore requiring management to utilize its own assumptions to provide its best estimate of what market participants would use in valuing the asset or liability.

The liability for the estimated fair value of the contingent consideration in connection with our acquisitions of Meridian Environmental Technology, Inc. (“MET”) and Berkeley Transportation Systems, Inc. (“BTS”) was determined using Level 3 inputs based on a probabilistic calculation whereby we assigned estimated probabilities to achieving the earn-out targets and then discounted the total contingent consideration to net present value. The following table reconciles this liability measured at fair value on a recurring basis for the three months ended June 30, 2012 (in thousands):

Balance at March 31, 2012	$	2,204
Deferred payments made to MET shareholders	—
Deferred payments made to BTS shareholders	—
Change in fair value included in net income	(334		)
Balance at June 30, 2012	$	1,870

The change in the estimated fair value of this liability during the current fiscal quarter resulted primarily from revisions to our estimates regarding both the probability of achieving certain earn-out targets and the amounts of certain future deferred payments.

The current portion of the liability at June 30, 2012 and March 31, 2012 was $1.9 million and $1.6 million, respectively, and was included within accrued liabilities in the accompanying unaudited consolidated balance sheets. The change in the estimated fair value of the liability for the three months ended June 30, 2012 and 2011 is included as part of operating expenses in the accompanying unaudited consolidated statements of operations.

Other than the above, we did not have any material financial assets or liabilities measured at fair value on a recurring basis using Level 3 inputs as of June 30, 2012 or March 31, 2012.

Our non-financial assets, such as goodwill, intangible assets and property and equipment, are measured at fair value on a non-recurring basis, generally when there is a transaction involving those assets such as a purchase transaction, a business combination or an adjustment for impairment. No non-financial assets were measured at fair value during the three months ended June 30, 2012 and 2011.