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Accrued Liabilities and Other Current Liabilities (Tables) | 3 Months Ended
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Mar. 31, 2019
Accrued Liabilities and Other Current Liabilities |
Schedule of accrued expenses and other current liabilities | Accrued expenses and other current liabilities consisted of the following (in thousands):
|  | March 31, |  | December 31,
|  | 2019 |  | 2018
Employee compensation expense |  | $ | 2,252 |  | $ | 3,130
Project asset costs |  |  | 1,091 |  |  | 2,014
Valve installation incentive(1) |  |  | — |  |  | 2,000
Accrued legal services |  |  | 306 |  |  | 313
Other accrued liabilities |  |  | 538 |  |  | 896
Total accrued liabilities and other current liabilities |  | $ | 4,187 |  | $ | 8,353
| (1) |  | In April 2018, we entered into an agreement with an intrastate pipeline company with assets near the Terminal which incentivizes such pipeline company to procure, permit and install a valve on an intrastate pipeline near the Terminal. We agreed that, upon the later of (i) March 31, 2019 and (ii) thirty days after the date on which the valve was installed, we will reimburse such pipeline company a cash amount equal to 50% of the costs incurred in connection with the valve, up to a maximum payment by us not to exceed $2.0 million. Such valve was installed in 2018 and we reimbursed such pipeline company $2.0 million in the first quarter of 2019.

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