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    <link:label id="lab_us-gaap_IncomeLossFromContinuingOperations_F4598F43FDE7479BA994CC41BBEEC8EF_totalLabel_en-US" xlink:label="lab_us-gaap_IncomeLossFromContinuingOperations_F4598F43FDE7479BA994CC41BBEEC8EF" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Net loss from continuing operations</link:label>
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    <link:label id="lab_us-gaap_BuildingMember_A7D9437FD7B2618D1E3AEAA47058469C_terseLabel_en-US" xlink:label="lab_us-gaap_BuildingMember_A7D9437FD7B2618D1E3AEAA47058469C" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Buildings</link:label>
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    <link:label id="lab_us-gaap_CapitalLeasesFutureMinimumPaymentsDueAbstract_7E023FD1D4CDB98371E9E71E2ABD2F30_label_en-US" xlink:label="lab_us-gaap_CapitalLeasesFutureMinimumPaymentsDueAbstract_7E023FD1D4CDB98371E9E71E2ABD2F30" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Capital Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_CapitalLeasesFutureMinimumPaymentsDueAbstract" xlink:label="loc_us-gaap_CapitalLeasesFutureMinimumPaymentsDueAbstract_7E023FD1D4CDB98371E9E71E2ABD2F30" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CapitalLeasesFutureMinimumPaymentsDueAbstract_7E023FD1D4CDB98371E9E71E2ABD2F30" xlink:to="lab_us-gaap_CapitalLeasesFutureMinimumPaymentsDueAbstract_7E023FD1D4CDB98371E9E71E2ABD2F30" xlink:type="arc" />
    <link:label id="lab_us-gaap_CapitalLeasesFutureMinimumPaymentsDueCurrent_ABB798FE30343BEAD7F5E71E2ABD9160_terseLabel_en-US" xlink:label="lab_us-gaap_CapitalLeasesFutureMinimumPaymentsDueCurrent_ABB798FE30343BEAD7F5E71E2ABD9160" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">2016</link:label>
    <link:label id="lab_us-gaap_CapitalLeasesFutureMinimumPaymentsDueCurrent_ABB798FE30343BEAD7F5E71E2ABD9160_label_en-US" xlink:label="lab_us-gaap_CapitalLeasesFutureMinimumPaymentsDueCurrent_ABB798FE30343BEAD7F5E71E2ABD9160" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Capital Leases, Future Minimum Payments Due, Next Twelve Months</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_CapitalLeasesFutureMinimumPaymentsDueCurrent" xlink:label="loc_us-gaap_CapitalLeasesFutureMinimumPaymentsDueCurrent_ABB798FE30343BEAD7F5E71E2ABD9160" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CapitalLeasesFutureMinimumPaymentsDueCurrent_ABB798FE30343BEAD7F5E71E2ABD9160" xlink:to="lab_us-gaap_CapitalLeasesFutureMinimumPaymentsDueCurrent_ABB798FE30343BEAD7F5E71E2ABD9160" xlink:type="arc" />
    <link:label id="lab_us-gaap_CapitalLeasesFutureMinimumPaymentsDueInTwoYears_F0073D865FDE961A3EEBE71E2ABD5BA0_terseLabel_en-US" xlink:label="lab_us-gaap_CapitalLeasesFutureMinimumPaymentsDueInTwoYears_F0073D865FDE961A3EEBE71E2ABD5BA0" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">2017</link:label>
    <link:label id="lab_us-gaap_CapitalLeasesFutureMinimumPaymentsDueInTwoYears_F0073D865FDE961A3EEBE71E2ABD5BA0_label_en-US" xlink:label="lab_us-gaap_CapitalLeasesFutureMinimumPaymentsDueInTwoYears_F0073D865FDE961A3EEBE71E2ABD5BA0" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Capital Leases, Future Minimum Payments Due in Two Years</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_CapitalLeasesFutureMinimumPaymentsDueInTwoYears" xlink:label="loc_us-gaap_CapitalLeasesFutureMinimumPaymentsDueInTwoYears_F0073D865FDE961A3EEBE71E2ABD5BA0" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CapitalLeasesFutureMinimumPaymentsDueInTwoYears_F0073D865FDE961A3EEBE71E2ABD5BA0" xlink:to="lab_us-gaap_CapitalLeasesFutureMinimumPaymentsDueInTwoYears_F0073D865FDE961A3EEBE71E2ABD5BA0" xlink:type="arc" />
    <link:label id="lab_us-gaap_CapitalLeasesFutureMinimumPaymentsDueInThreeYears_7ED6AFC7E73AC9C82DA6E71E2ABDD4EB_terseLabel_en-US" xlink:label="lab_us-gaap_CapitalLeasesFutureMinimumPaymentsDueInThreeYears_7ED6AFC7E73AC9C82DA6E71E2ABDD4EB" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">2018</link:label>
    <link:label id="lab_us-gaap_CapitalLeasesFutureMinimumPaymentsDueInThreeYears_7ED6AFC7E73AC9C82DA6E71E2ABDD4EB_label_en-US" xlink:label="lab_us-gaap_CapitalLeasesFutureMinimumPaymentsDueInThreeYears_7ED6AFC7E73AC9C82DA6E71E2ABDD4EB" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Capital Leases, Future Minimum Payments Due in Three Years</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_CapitalLeasesFutureMinimumPaymentsDueInThreeYears" xlink:label="loc_us-gaap_CapitalLeasesFutureMinimumPaymentsDueInThreeYears_7ED6AFC7E73AC9C82DA6E71E2ABDD4EB" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CapitalLeasesFutureMinimumPaymentsDueInThreeYears_7ED6AFC7E73AC9C82DA6E71E2ABDD4EB" xlink:to="lab_us-gaap_CapitalLeasesFutureMinimumPaymentsDueInThreeYears_7ED6AFC7E73AC9C82DA6E71E2ABDD4EB" xlink:type="arc" />
    <link:label id="lab_us-gaap_CapitalLeasesFutureMinimumPaymentsDueInFourYears_5CF1AC635F8FFC496EF3E71E2ABDF661_terseLabel_en-US" xlink:label="lab_us-gaap_CapitalLeasesFutureMinimumPaymentsDueInFourYears_5CF1AC635F8FFC496EF3E71E2ABDF661" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">2019</link:label>
    <link:label id="lab_us-gaap_CapitalLeasesFutureMinimumPaymentsDueInFourYears_5CF1AC635F8FFC496EF3E71E2ABDF661_label_en-US" xlink:label="lab_us-gaap_CapitalLeasesFutureMinimumPaymentsDueInFourYears_5CF1AC635F8FFC496EF3E71E2ABDF661" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Capital Leases, Future Minimum Payments Due in Four Years</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_CapitalLeasesFutureMinimumPaymentsDueInFourYears" xlink:label="loc_us-gaap_CapitalLeasesFutureMinimumPaymentsDueInFourYears_5CF1AC635F8FFC496EF3E71E2ABDF661" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CapitalLeasesFutureMinimumPaymentsDueInFourYears_5CF1AC635F8FFC496EF3E71E2ABDF661" xlink:to="lab_us-gaap_CapitalLeasesFutureMinimumPaymentsDueInFourYears_5CF1AC635F8FFC496EF3E71E2ABDF661" xlink:type="arc" />
    <link:label id="lab_us-gaap_CapitalLeasesFutureMinimumPaymentsDueInFiveYears_0EFA4477FE8ED9A6E28BE71E2ABD0091_terseLabel_en-US" xlink:label="lab_us-gaap_CapitalLeasesFutureMinimumPaymentsDueInFiveYears_0EFA4477FE8ED9A6E28BE71E2ABD0091" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">2020 and thereafter</link:label>
    <link:label id="lab_us-gaap_CapitalLeasesFutureMinimumPaymentsDueInFiveYears_0EFA4477FE8ED9A6E28BE71E2ABD0091_label_en-US" xlink:label="lab_us-gaap_CapitalLeasesFutureMinimumPaymentsDueInFiveYears_0EFA4477FE8ED9A6E28BE71E2ABD0091" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Capital Leases, Future Minimum Payments Due in Five Years</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_CapitalLeasesFutureMinimumPaymentsDueInFiveYears" xlink:label="loc_us-gaap_CapitalLeasesFutureMinimumPaymentsDueInFiveYears_0EFA4477FE8ED9A6E28BE71E2ABD0091" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CapitalLeasesFutureMinimumPaymentsDueInFiveYears_0EFA4477FE8ED9A6E28BE71E2ABD0091" xlink:to="lab_us-gaap_CapitalLeasesFutureMinimumPaymentsDueInFiveYears_0EFA4477FE8ED9A6E28BE71E2ABD0091" xlink:type="arc" />
    <link:label id="lab_us-gaap_CapitalLeasesFutureMinimumPaymentsDue_90A425B95B30EECE7DD5E71E2ABD1C77_totalLabel_en-US" xlink:label="lab_us-gaap_CapitalLeasesFutureMinimumPaymentsDue_90A425B95B30EECE7DD5E71E2ABD1C77" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Subtotal:</link:label>
    <link:label id="lab_us-gaap_CapitalLeasesFutureMinimumPaymentsDue_90A425B95B30EECE7DD5E71E2ABD1C77_label_en-US" xlink:label="lab_us-gaap_CapitalLeasesFutureMinimumPaymentsDue_90A425B95B30EECE7DD5E71E2ABD1C77" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Capital Leases, Future Minimum Payments Due</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_CapitalLeasesFutureMinimumPaymentsDue" xlink:label="loc_us-gaap_CapitalLeasesFutureMinimumPaymentsDue_90A425B95B30EECE7DD5E71E2ABD1C77" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CapitalLeasesFutureMinimumPaymentsDue_90A425B95B30EECE7DD5E71E2ABD1C77" xlink:to="lab_us-gaap_CapitalLeasesFutureMinimumPaymentsDue_90A425B95B30EECE7DD5E71E2ABD1C77" xlink:type="arc" />
    <link:label id="lab_us-gaap_CapitalLeasesFutureMinimumPaymentsInterestIncludedInPayments_D381FF9FA78A102E287BE71E2ABD7A88_negatedTerseLabel_en-US" xlink:label="lab_us-gaap_CapitalLeasesFutureMinimumPaymentsInterestIncludedInPayments_D381FF9FA78A102E287BE71E2ABD7A88" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Less: amount representing interest</link:label>
    <link:label id="lab_us-gaap_CapitalLeasesFutureMinimumPaymentsInterestIncludedInPayments_D381FF9FA78A102E287BE71E2ABD7A88_label_en-US" xlink:label="lab_us-gaap_CapitalLeasesFutureMinimumPaymentsInterestIncludedInPayments_D381FF9FA78A102E287BE71E2ABD7A88" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Capital Leases, Future Minimum Payments, Interest Included in Payments</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_CapitalLeasesFutureMinimumPaymentsInterestIncludedInPayments" xlink:label="loc_us-gaap_CapitalLeasesFutureMinimumPaymentsInterestIncludedInPayments_D381FF9FA78A102E287BE71E2ABD7A88" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CapitalLeasesFutureMinimumPaymentsInterestIncludedInPayments_D381FF9FA78A102E287BE71E2ABD7A88" xlink:to="lab_us-gaap_CapitalLeasesFutureMinimumPaymentsInterestIncludedInPayments_D381FF9FA78A102E287BE71E2ABD7A88" xlink:type="arc" />
    <link:label id="lab_us-gaap_CapitalLeasesFutureMinimumPaymentsPresentValueOfNetMinimumPayments_FF10AF010556D4FA4256E71E2ABD95B5_totalLabel_en-US" xlink:label="lab_us-gaap_CapitalLeasesFutureMinimumPaymentsPresentValueOfNetMinimumPayments_FF10AF010556D4FA4256E71E2ABD95B5" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Present value of minimum lease payments</link:label>
    <link:label id="lab_us-gaap_CapitalLeasesFutureMinimumPaymentsPresentValueOfNetMinimumPayments_FF10AF010556D4FA4256E71E2ABD95B5_label_en-US" xlink:label="lab_us-gaap_CapitalLeasesFutureMinimumPaymentsPresentValueOfNetMinimumPayments_FF10AF010556D4FA4256E71E2ABD95B5" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Capital Leases, Future Minimum Payments, Present Value of Net Minimum Payments</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_CapitalLeasesFutureMinimumPaymentsPresentValueOfNetMinimumPayments" xlink:label="loc_us-gaap_CapitalLeasesFutureMinimumPaymentsPresentValueOfNetMinimumPayments_FF10AF010556D4FA4256E71E2ABD95B5" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CapitalLeasesFutureMinimumPaymentsPresentValueOfNetMinimumPayments_FF10AF010556D4FA4256E71E2ABD95B5" xlink:to="lab_us-gaap_CapitalLeasesFutureMinimumPaymentsPresentValueOfNetMinimumPayments_FF10AF010556D4FA4256E71E2ABD95B5" xlink:type="arc" />
    <link:label id="lab_us-gaap_CapitalLeaseObligationsCurrent_79AF7A80DC683AB9B33EE71E2ABD486D_negatedTerseLabel_en-US" xlink:label="lab_us-gaap_CapitalLeaseObligationsCurrent_79AF7A80DC683AB9B33EE71E2ABD486D" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Less: current portion</link:label>
    <link:label id="lab_us-gaap_CapitalLeaseObligationsCurrent_79AF7A80DC683AB9B33EE71E2ABD486D_label_en-US" xlink:label="lab_us-gaap_CapitalLeaseObligationsCurrent_79AF7A80DC683AB9B33EE71E2ABD486D" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Capital Lease Obligations, Current</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_CapitalLeaseObligationsCurrent" xlink:label="loc_us-gaap_CapitalLeaseObligationsCurrent_79AF7A80DC683AB9B33EE71E2ABD486D" xlink:type="locator" />
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    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_CapitalLeaseObligationsNoncurrent" xlink:label="loc_us-gaap_CapitalLeaseObligationsNoncurrent_64C713FCC0FDE2BB29CCE71E2ABD1392" xlink:type="locator" />
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    <link:loc xlink:href="noa-20151231.xsd#noa_AcquisitionOfPropertyPlantAndEquipmentMember" xlink:label="loc_noa_AcquisitionOfPropertyPlantAndEquipmentMember_16A7783E885FCAD51AA6EAA46ECB5DF7" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_noa_AcquisitionOfPropertyPlantAndEquipmentMember_16A7783E885FCAD51AA6EAA46ECB5DF7" xlink:to="lab_noa_AcquisitionOfPropertyPlantAndEquipmentMember_16A7783E885FCAD51AA6EAA46ECB5DF7" xlink:type="arc" />
    <link:label id="lab_us-gaap_NoncashOrPartNoncashAcquisitionsLineItems_5637FEC52513573A86EFEAA46ECC08F1_terseLabel_en-US" xlink:label="lab_us-gaap_NoncashOrPartNoncashAcquisitionsLineItems_5637FEC52513573A86EFEAA46ECC08F1" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Noncash or Part Noncash Acquisitions [Line Items]</link:label>
    <link:label id="lab_us-gaap_NoncashOrPartNoncashAcquisitionsLineItems_5637FEC52513573A86EFEAA46ECC08F1_label_en-US" xlink:label="lab_us-gaap_NoncashOrPartNoncashAcquisitionsLineItems_5637FEC52513573A86EFEAA46ECC08F1" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Noncash or Part Noncash Acquisitions [Line Items]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_NoncashOrPartNoncashAcquisitionsLineItems" xlink:label="loc_us-gaap_NoncashOrPartNoncashAcquisitionsLineItems_5637FEC52513573A86EFEAA46ECC08F1" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NoncashOrPartNoncashAcquisitionsLineItems_5637FEC52513573A86EFEAA46ECC08F1" xlink:to="lab_us-gaap_NoncashOrPartNoncashAcquisitionsLineItems_5637FEC52513573A86EFEAA46ECC08F1" xlink:type="arc" />
    <link:label id="lab_noa_CashFlowNonCashTransactionsAbstract_EDE838B080DC70DDD13FEAA46ECCE65A_terseLabel_en-US" xlink:label="lab_noa_CashFlowNonCashTransactionsAbstract_EDE838B080DC70DDD13FEAA46ECCE65A" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Non-cash transactions:</link:label>
    <link:label id="lab_noa_CashFlowNonCashTransactionsAbstract_EDE838B080DC70DDD13FEAA46ECCE65A_label_en-US" xlink:label="lab_noa_CashFlowNonCashTransactionsAbstract_EDE838B080DC70DDD13FEAA46ECCE65A" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Cash Flow, Non-cash Transactions [Abstract]</link:label>
    <link:label id="lab_noa_CashFlowNonCashTransactionsAbstract_EDE838B080DC70DDD13FEAA46ECCE65A_documentation_en-US" xlink:label="lab_noa_CashFlowNonCashTransactionsAbstract_EDE838B080DC70DDD13FEAA46ECCE65A" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Cash Flow, Non-cash Transactions [Abstract]</link:label>
    <link:loc xlink:href="noa-20151231.xsd#noa_CashFlowNonCashTransactionsAbstract" xlink:label="loc_noa_CashFlowNonCashTransactionsAbstract_EDE838B080DC70DDD13FEAA46ECCE65A" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_noa_CashFlowNonCashTransactionsAbstract_EDE838B080DC70DDD13FEAA46ECCE65A" xlink:to="lab_noa_CashFlowNonCashTransactionsAbstract_EDE838B080DC70DDD13FEAA46ECCE65A" xlink:type="arc" />
    <link:label id="lab_noa_AdditionsToAssetsHeldForSale_2B278EFEAE7A9F2001FBEAA46ECCC6A7_negatedTerseLabel_en-US" xlink:label="lab_noa_AdditionsToAssetsHeldForSale_2B278EFEAE7A9F2001FBEAA46ECCC6A7" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Reclass from plant and equipment to assets held for sale</link:label>
    <link:label id="lab_noa_AdditionsToAssetsHeldForSale_2B278EFEAE7A9F2001FBEAA46ECCC6A7_label_en-US" xlink:label="lab_noa_AdditionsToAssetsHeldForSale_2B278EFEAE7A9F2001FBEAA46ECCC6A7" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Additions to Assets Held for Sale</link:label>
    <link:label id="lab_noa_AdditionsToAssetsHeldForSale_2B278EFEAE7A9F2001FBEAA46ECCC6A7_documentation_en-US" xlink:label="lab_noa_AdditionsToAssetsHeldForSale_2B278EFEAE7A9F2001FBEAA46ECCC6A7" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Additions to Assets Held for Sale</link:label>
    <link:loc xlink:href="noa-20151231.xsd#noa_AdditionsToAssetsHeldForSale" xlink:label="loc_noa_AdditionsToAssetsHeldForSale_2B278EFEAE7A9F2001FBEAA46ECCC6A7" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_noa_AdditionsToAssetsHeldForSale_2B278EFEAE7A9F2001FBEAA46ECCC6A7" xlink:to="lab_noa_AdditionsToAssetsHeldForSale_2B278EFEAE7A9F2001FBEAA46ECCC6A7" xlink:type="arc" />
    <link:label id="lab_us-gaap_CashFlowNoncashInvestingAndFinancingActivitiesDisclosureAbstract_CE36B372CFB003B8945CEAA46ECC01B3_terseLabel_en-US" xlink:label="lab_us-gaap_CashFlowNoncashInvestingAndFinancingActivitiesDisclosureAbstract_CE36B372CFB003B8945CEAA46ECC01B3" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Non-cash working capital exclusions:</link:label>
    <link:label id="lab_us-gaap_CashFlowNoncashInvestingAndFinancingActivitiesDisclosureAbstract_CE36B372CFB003B8945CEAA46ECC01B3_label_en-US" xlink:label="lab_us-gaap_CashFlowNoncashInvestingAndFinancingActivitiesDisclosureAbstract_CE36B372CFB003B8945CEAA46ECC01B3" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Cash Flow, Noncash Investing and Financing Activities Disclosure [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_CashFlowNoncashInvestingAndFinancingActivitiesDisclosureAbstract" xlink:label="loc_us-gaap_CashFlowNoncashInvestingAndFinancingActivitiesDisclosureAbstract_CE36B372CFB003B8945CEAA46ECC01B3" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CashFlowNoncashInvestingAndFinancingActivitiesDisclosureAbstract_CE36B372CFB003B8945CEAA46ECC01B3" xlink:to="lab_us-gaap_CashFlowNoncashInvestingAndFinancingActivitiesDisclosureAbstract_CE36B372CFB003B8945CEAA46ECC01B3" xlink:type="arc" />
    <link:label id="lab_noa_ReclassificationfromInventorytoPlantandEquipment_D2FF89DC98389CD79C73EAA46ECC44F5_terseLabel_en-US" xlink:label="lab_noa_ReclassificationfromInventorytoPlantandEquipment_D2FF89DC98389CD79C73EAA46ECC44F5" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Decrease in inventory resulting from reclassification to plant and equipment</link:label>
    <link:label id="lab_noa_ReclassificationfromInventorytoPlantandEquipment_D2FF89DC98389CD79C73EAA46ECC44F5_label_en-US" xlink:label="lab_noa_ReclassificationfromInventorytoPlantandEquipment_D2FF89DC98389CD79C73EAA46ECC44F5" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Reclassification from Inventory to Plant and Equipment</link:label>
    <link:label id="lab_noa_ReclassificationfromInventorytoPlantandEquipment_D2FF89DC98389CD79C73EAA46ECC44F5_documentation_en-US" xlink:label="lab_noa_ReclassificationfromInventorytoPlantandEquipment_D2FF89DC98389CD79C73EAA46ECC44F5" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Reclassification from Inventory to Plant and Equipment</link:label>
    <link:loc xlink:href="noa-20151231.xsd#noa_ReclassificationfromInventorytoPlantandEquipment" xlink:label="loc_noa_ReclassificationfromInventorytoPlantandEquipment_D2FF89DC98389CD79C73EAA46ECC44F5" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_noa_ReclassificationfromInventorytoPlantandEquipment_D2FF89DC98389CD79C73EAA46ECC44F5" xlink:to="lab_noa_ReclassificationfromInventorytoPlantandEquipment_D2FF89DC98389CD79C73EAA46ECC44F5" xlink:type="arc" />
    <link:label id="lab_us-gaap_NoncashOrPartNoncashDivestitureAmountOfConsiderationReceived1_678E1501E6658164532BEAA46ECC583B_terseLabel_en-US" xlink:label="lab_us-gaap_NoncashOrPartNoncashDivestitureAmountOfConsiderationReceived1_678E1501E6658164532BEAA46ECC583B" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Net increase in accounts receivable related to sale of plant and equipment</link:label>
    <link:label id="lab_us-gaap_NoncashOrPartNoncashDivestitureAmountOfConsiderationReceived1_678E1501E6658164532BEAA46ECC583B_label_en-US" xlink:label="lab_us-gaap_NoncashOrPartNoncashDivestitureAmountOfConsiderationReceived1_678E1501E6658164532BEAA46ECC583B" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Noncash or Part Noncash Divestiture, Amount of Consideration Received</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_NoncashOrPartNoncashDivestitureAmountOfConsiderationReceived1" xlink:label="loc_us-gaap_NoncashOrPartNoncashDivestitureAmountOfConsiderationReceived1_678E1501E6658164532BEAA46ECC583B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NoncashOrPartNoncashDivestitureAmountOfConsiderationReceived1_678E1501E6658164532BEAA46ECC583B" xlink:to="lab_us-gaap_NoncashOrPartNoncashDivestitureAmountOfConsiderationReceived1_678E1501E6658164532BEAA46ECC583B" xlink:type="arc" />
    <link:label id="lab_us-gaap_NoncashOrPartNoncashAcquisitionPayablesAssumed1_EF83FC332339D66EF726EAA46ECCD08D_terseLabel_en-US" xlink:label="lab_us-gaap_NoncashOrPartNoncashAcquisitionPayablesAssumed1_EF83FC332339D66EF726EAA46ECCD08D" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Net (decrease) increase in accounts payable related to purchase of plant and equipment</link:label>
    <link:label id="lab_us-gaap_NoncashOrPartNoncashAcquisitionPayablesAssumed1_EF83FC332339D66EF726EAA46ECCD08D_label_en-US" xlink:label="lab_us-gaap_NoncashOrPartNoncashAcquisitionPayablesAssumed1_EF83FC332339D66EF726EAA46ECCD08D" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Noncash or Part Noncash Acquisition, Payables Assumed</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_NoncashOrPartNoncashAcquisitionPayablesAssumed1" xlink:label="loc_us-gaap_NoncashOrPartNoncashAcquisitionPayablesAssumed1_EF83FC332339D66EF726EAA46ECCD08D" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NoncashOrPartNoncashAcquisitionPayablesAssumed1_EF83FC332339D66EF726EAA46ECCD08D" xlink:to="lab_us-gaap_NoncashOrPartNoncashAcquisitionPayablesAssumed1_EF83FC332339D66EF726EAA46ECCD08D" xlink:type="arc" />
    <link:label id="lab_noa_NoncashTransactionIncreaseDecreaseinAccountsPayablePurchaseofIntangibles_0D340D241E91D7A0006CEAA46ECCEC17_negatedTerseLabel_en-US" xlink:label="lab_noa_NoncashTransactionIncreaseDecreaseinAccountsPayablePurchaseofIntangibles_0D340D241E91D7A0006CEAA46ECCEC17" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Net decrease in accounts payable related to change in estimated financing costs</link:label>
    <link:label id="lab_noa_NoncashTransactionIncreaseDecreaseinAccountsPayablePurchaseofIntangibles_0D340D241E91D7A0006CEAA46ECCEC17_label_en-US" xlink:label="lab_noa_NoncashTransactionIncreaseDecreaseinAccountsPayablePurchaseofIntangibles_0D340D241E91D7A0006CEAA46ECCEC17" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Noncash Transaction, Increase (Decrease) in Accounts Payable, Purchase of Intangibles</link:label>
    <link:label id="lab_noa_NoncashTransactionIncreaseDecreaseinAccountsPayablePurchaseofIntangibles_0D340D241E91D7A0006CEAA46ECCEC17_documentation_en-US" xlink:label="lab_noa_NoncashTransactionIncreaseDecreaseinAccountsPayablePurchaseofIntangibles_0D340D241E91D7A0006CEAA46ECCEC17" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Noncash Transaction, Increase (Decrease) in Accounts Payable, Purchase of Intangibles</link:label>
    <link:loc xlink:href="noa-20151231.xsd#noa_NoncashTransactionIncreaseDecreaseinAccountsPayablePurchaseofIntangibles" xlink:label="loc_noa_NoncashTransactionIncreaseDecreaseinAccountsPayablePurchaseofIntangibles_0D340D241E91D7A0006CEAA46ECCEC17" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_noa_NoncashTransactionIncreaseDecreaseinAccountsPayablePurchaseofIntangibles_0D340D241E91D7A0006CEAA46ECCEC17" xlink:to="lab_noa_NoncashTransactionIncreaseDecreaseinAccountsPayablePurchaseofIntangibles_0D340D241E91D7A0006CEAA46ECCEC17" xlink:type="arc" />
    <link:label id="lab_noa_NoncashTransactionIncreaseDecreaseinAccountsPayableChangetoLeaseInducementPayable_D0451330295519228CB6EAA46ECC16A0_terseLabel_en-US" xlink:label="lab_noa_NoncashTransactionIncreaseDecreaseinAccountsPayableChangetoLeaseInducementPayable_D0451330295519228CB6EAA46ECC16A0" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Net (decrease) increase in accounts payable related to change in the lease inducement payable on the sublease</link:label>
    <link:label id="lab_noa_NoncashTransactionIncreaseDecreaseinAccountsPayableChangetoLeaseInducementPayable_D0451330295519228CB6EAA46ECC16A0_label_en-US" xlink:label="lab_noa_NoncashTransactionIncreaseDecreaseinAccountsPayableChangetoLeaseInducementPayable_D0451330295519228CB6EAA46ECC16A0" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Noncash Transaction, Increase (Decrease) in Accounts Payable, Change to Lease Inducement Payable</link:label>
    <link:label id="lab_noa_NoncashTransactionIncreaseDecreaseinAccountsPayableChangetoLeaseInducementPayable_D0451330295519228CB6EAA46ECC16A0_documentation_en-US" xlink:label="lab_noa_NoncashTransactionIncreaseDecreaseinAccountsPayableChangetoLeaseInducementPayable_D0451330295519228CB6EAA46ECC16A0" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Noncash Transaction, Increase (Decrease) in Accounts Payable, Change to Lease Inducement Payable</link:label>
    <link:loc xlink:href="noa-20151231.xsd#noa_NoncashTransactionIncreaseDecreaseinAccountsPayableChangetoLeaseInducementPayable" xlink:label="loc_noa_NoncashTransactionIncreaseDecreaseinAccountsPayableChangetoLeaseInducementPayable_D0451330295519228CB6EAA46ECC16A0" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_noa_NoncashTransactionIncreaseDecreaseinAccountsPayableChangetoLeaseInducementPayable_D0451330295519228CB6EAA46ECC16A0" xlink:to="lab_noa_NoncashTransactionIncreaseDecreaseinAccountsPayableChangetoLeaseInducementPayable_D0451330295519228CB6EAA46ECC16A0" xlink:type="arc" />
    <link:label id="lab_noa_NoncashTransactionIncreaseDecreaseinEquipmentLeaseLiabilitiesCurrent_10ABEC854E9540ECDBF9EAA46ECCBB96_terseLabel_en-US" xlink:label="lab_noa_NoncashTransactionIncreaseDecreaseinEquipmentLeaseLiabilitiesCurrent_10ABEC854E9540ECDBF9EAA46ECCBB96" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Net decrease in short term portion of equipment lease liabilities included in accrued liabilities related to the purchase of plant and equipment</link:label>
    <link:label id="lab_noa_NoncashTransactionIncreaseDecreaseinEquipmentLeaseLiabilitiesCurrent_10ABEC854E9540ECDBF9EAA46ECCBB96_label_en-US" xlink:label="lab_noa_NoncashTransactionIncreaseDecreaseinEquipmentLeaseLiabilitiesCurrent_10ABEC854E9540ECDBF9EAA46ECCBB96" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Noncash Transaction, Increase (Decrease) in Equipment Lease Liabilities, Current</link:label>
    <link:label id="lab_noa_NoncashTransactionIncreaseDecreaseinEquipmentLeaseLiabilitiesCurrent_10ABEC854E9540ECDBF9EAA46ECCBB96_documentation_en-US" xlink:label="lab_noa_NoncashTransactionIncreaseDecreaseinEquipmentLeaseLiabilitiesCurrent_10ABEC854E9540ECDBF9EAA46ECCBB96" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Noncash Transaction, Increase (Decrease) in Equipment Lease Liabilities, Current</link:label>
    <link:loc xlink:href="noa-20151231.xsd#noa_NoncashTransactionIncreaseDecreaseinEquipmentLeaseLiabilitiesCurrent" xlink:label="loc_noa_NoncashTransactionIncreaseDecreaseinEquipmentLeaseLiabilitiesCurrent_10ABEC854E9540ECDBF9EAA46ECCBB96" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_noa_NoncashTransactionIncreaseDecreaseinEquipmentLeaseLiabilitiesCurrent_10ABEC854E9540ECDBF9EAA46ECCBB96" xlink:to="lab_noa_NoncashTransactionIncreaseDecreaseinEquipmentLeaseLiabilitiesCurrent_10ABEC854E9540ECDBF9EAA46ECCBB96" xlink:type="arc" />
    <link:label id="lab_noa_NoncashTransactionIncreaseDecreaseinEquipmentLeaseLiabilitiesNoncurrent_CF388A404F8566DF5730EAA46ECC7657_terseLabel_en-US" xlink:label="lab_noa_NoncashTransactionIncreaseDecreaseinEquipmentLeaseLiabilitiesNoncurrent_CF388A404F8566DF5730EAA46ECC7657" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Net increase in long term portion of equipment lease liabilities related to the purchase of plant and equipment</link:label>
    <link:label id="lab_noa_NoncashTransactionIncreaseDecreaseinEquipmentLeaseLiabilitiesNoncurrent_CF388A404F8566DF5730EAA46ECC7657_label_en-US" xlink:label="lab_noa_NoncashTransactionIncreaseDecreaseinEquipmentLeaseLiabilitiesNoncurrent_CF388A404F8566DF5730EAA46ECC7657" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Noncash Transaction, Increase (Decrease) in Equipment Lease Liabilities, Non-current</link:label>
    <link:label id="lab_noa_NoncashTransactionIncreaseDecreaseinEquipmentLeaseLiabilitiesNoncurrent_CF388A404F8566DF5730EAA46ECC7657_documentation_en-US" xlink:label="lab_noa_NoncashTransactionIncreaseDecreaseinEquipmentLeaseLiabilitiesNoncurrent_CF388A404F8566DF5730EAA46ECC7657" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Noncash Transaction, Increase (Decrease) in Equipment Lease Liabilities, Non-current</link:label>
    <link:loc xlink:href="noa-20151231.xsd#noa_NoncashTransactionIncreaseDecreaseinEquipmentLeaseLiabilitiesNoncurrent" xlink:label="loc_noa_NoncashTransactionIncreaseDecreaseinEquipmentLeaseLiabilitiesNoncurrent_CF388A404F8566DF5730EAA46ECC7657" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_noa_NoncashTransactionIncreaseDecreaseinEquipmentLeaseLiabilitiesNoncurrent_CF388A404F8566DF5730EAA46ECC7657" xlink:to="lab_noa_NoncashTransactionIncreaseDecreaseinEquipmentLeaseLiabilitiesNoncurrent_CF388A404F8566DF5730EAA46ECC7657" xlink:type="arc" />
    <link:label id="lab_noa_NoncashTransactionIncreaseDecreaseinAccruedLiabilitiesSaleLeasebackCurrent_1CA2A2D24C7443CF4EB5EAA46ECC9E2C_terseLabel_en-US" xlink:label="lab_noa_NoncashTransactionIncreaseDecreaseinAccruedLiabilitiesSaleLeasebackCurrent_1CA2A2D24C7443CF4EB5EAA46ECC9E2C" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Increase in accrued liabilities related to the current portion of the deferred gain on sale leaseback</link:label>
    <link:label id="lab_noa_NoncashTransactionIncreaseDecreaseinAccruedLiabilitiesSaleLeasebackCurrent_1CA2A2D24C7443CF4EB5EAA46ECC9E2C_label_en-US" xlink:label="lab_noa_NoncashTransactionIncreaseDecreaseinAccruedLiabilitiesSaleLeasebackCurrent_1CA2A2D24C7443CF4EB5EAA46ECC9E2C" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Noncash Transaction, Increase (Decrease) in Accrued Liabilities, Sale Leaseback, Current</link:label>
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    <link:label id="lab_noa_IncreaseDecreaseInAccruedShareBasedCompensationLiabilities_6A24A54A2022C1E0D437EAA46ECC5830_terseLabel_en-US" xlink:label="lab_noa_IncreaseDecreaseInAccruedShareBasedCompensationLiabilities_6A24A54A2022C1E0D437EAA46ECC5830" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Net change in accrued liabilities related to current portion of plan liabilities</link:label>
    <link:label id="lab_noa_IncreaseDecreaseInAccruedShareBasedCompensationLiabilities_6A24A54A2022C1E0D437EAA46ECC5830_label_en-US" xlink:label="lab_noa_IncreaseDecreaseInAccruedShareBasedCompensationLiabilities_6A24A54A2022C1E0D437EAA46ECC5830" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Increase (Decrease) in Accrued Share-based Compensation Liabilities</link:label>
    <link:label id="lab_noa_IncreaseDecreaseInAccruedShareBasedCompensationLiabilities_6A24A54A2022C1E0D437EAA46ECC5830_documentation_en-US" xlink:label="lab_noa_IncreaseDecreaseInAccruedShareBasedCompensationLiabilities_6A24A54A2022C1E0D437EAA46ECC5830" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Increase (Decrease) in Accrued Share-based Compensation Liabilities</link:label>
    <link:loc xlink:href="noa-20151231.xsd#noa_IncreaseDecreaseInAccruedShareBasedCompensationLiabilities" xlink:label="loc_noa_IncreaseDecreaseInAccruedShareBasedCompensationLiabilities_6A24A54A2022C1E0D437EAA46ECC5830" xlink:type="locator" />
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    <link:label id="lab_noa_NoncashTransactionIncreaseDecreaseinAccruedLiabilitiesDividendsPayable_23055D97CB9FF83EBE85EAA46ECCDF22_terseLabel_en-US" xlink:label="lab_noa_NoncashTransactionIncreaseDecreaseinAccruedLiabilitiesDividendsPayable_23055D97CB9FF83EBE85EAA46ECCDF22" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Net (decrease) increase in accrued liabilities related to dividend payable</link:label>
    <link:label id="lab_noa_NoncashTransactionIncreaseDecreaseinAccruedLiabilitiesDividendsPayable_23055D97CB9FF83EBE85EAA46ECCDF22_label_en-US" xlink:label="lab_noa_NoncashTransactionIncreaseDecreaseinAccruedLiabilitiesDividendsPayable_23055D97CB9FF83EBE85EAA46ECCDF22" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Noncash Transaction, Increase (Decrease) in Accrued Liabilities, Dividends Payable</link:label>
    <link:label id="lab_noa_NoncashTransactionIncreaseDecreaseinAccruedLiabilitiesDividendsPayable_23055D97CB9FF83EBE85EAA46ECCDF22_documentation_en-US" xlink:label="lab_noa_NoncashTransactionIncreaseDecreaseinAccruedLiabilitiesDividendsPayable_23055D97CB9FF83EBE85EAA46ECCDF22" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Noncash Transaction, Increase (Decrease) in Accrued Liabilities, Dividends Payable</link:label>
    <link:loc xlink:href="noa-20151231.xsd#noa_NoncashTransactionIncreaseDecreaseinAccruedLiabilitiesDividendsPayable" xlink:label="loc_noa_NoncashTransactionIncreaseDecreaseinAccruedLiabilitiesDividendsPayable_23055D97CB9FF83EBE85EAA46ECCDF22" xlink:type="locator" />
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    <link:label id="lab_noa_CashFlowsNonCashTransactionsRelatedToDiscontinuedOperationsAbstract_5996710B83D3370D6484EAA46ECD5A48_label_en-US" xlink:label="lab_noa_CashFlowsNonCashTransactionsRelatedToDiscontinuedOperationsAbstract_5996710B83D3370D6484EAA46ECD5A48" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Cash Flows, Non-cash Transactions Related to Discontinued Operations [Abstract]</link:label>
    <link:label id="lab_noa_CashFlowsNonCashTransactionsRelatedToDiscontinuedOperationsAbstract_5996710B83D3370D6484EAA46ECD5A48_documentation_en-US" xlink:label="lab_noa_CashFlowsNonCashTransactionsRelatedToDiscontinuedOperationsAbstract_5996710B83D3370D6484EAA46ECD5A48" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Cash Flows, Non-cash Transactions Related to Discontinued Operations [Abstract]</link:label>
    <link:loc xlink:href="noa-20151231.xsd#noa_CashFlowsNonCashTransactionsRelatedToDiscontinuedOperationsAbstract" xlink:label="loc_noa_CashFlowsNonCashTransactionsRelatedToDiscontinuedOperationsAbstract_5996710B83D3370D6484EAA46ECD5A48" xlink:type="locator" />
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    <link:label id="lab_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_2D88E41BEE7B209A777BEAA46ECD96E5_terseLabel_en-US" xlink:label="lab_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_2D88E41BEE7B209A777BEAA46ECD96E5" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Operating activities:</link:label>
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    <link:label id="lab_us-gaap_IncreaseDecreaseInAccountsReceivable_5D86A13BE1762944A788EAA46ECDB930_negatedTerseLabel_en-US" xlink:label="lab_us-gaap_IncreaseDecreaseInAccountsReceivable_5D86A13BE1762944A788EAA46ECDB930" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Accounts receivable</link:label>
    <link:label id="lab_us-gaap_IncreaseDecreaseInAccountsReceivable_5D86A13BE1762944A788EAA46ECDB930_label_en-US" xlink:label="lab_us-gaap_IncreaseDecreaseInAccountsReceivable_5D86A13BE1762944A788EAA46ECDB930" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Increase (Decrease) in Accounts Receivable</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_IncreaseDecreaseInAccountsReceivable" xlink:label="loc_us-gaap_IncreaseDecreaseInAccountsReceivable_5D86A13BE1762944A788EAA46ECDB930" xlink:type="locator" />
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    <link:label id="lab_us-gaap_IncreaseDecreaseInUnbilledReceivables_24C0B585184577FAD8C5EAA46ECDC129_negatedTerseLabel_en-US" xlink:label="lab_us-gaap_IncreaseDecreaseInUnbilledReceivables_24C0B585184577FAD8C5EAA46ECDC129" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Unbilled revenue</link:label>
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    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_IncreaseDecreaseInUnbilledReceivables" xlink:label="loc_us-gaap_IncreaseDecreaseInUnbilledReceivables_24C0B585184577FAD8C5EAA46ECDC129" xlink:type="locator" />
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    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets" xlink:label="loc_us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets_2D3670CA151334D2105CEAA46ECDE0D9" xlink:type="locator" />
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    <link:label id="lab_us-gaap_IncreaseDecreaseInBillingInExcessOfCostOfEarnings_826CF4CBBA970CA9733AEAA46ECDC965_terseLabel_en-US" xlink:label="lab_us-gaap_IncreaseDecreaseInBillingInExcessOfCostOfEarnings_826CF4CBBA970CA9733AEAA46ECDC965" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Billings in excess of costs incurred and estimated earnings on uncompleted contracts</link:label>
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    <link:loc xlink:href="noa-20151231.xsd#noa_ScheduleOfLeaseIncentivesTableTextBlock" xlink:label="loc_noa_ScheduleOfLeaseIncentivesTableTextBlock_E30AE74E835DD4C7EF1E21779BB02099" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_noa_ScheduleOfLeaseIncentivesTableTextBlock_E30AE74E835DD4C7EF1E21779BB02099" xlink:to="lab_noa_ScheduleOfLeaseIncentivesTableTextBlock_E30AE74E835DD4C7EF1E21779BB02099" xlink:type="arc" />
    <link:label id="lab_us-gaap_ScheduleOfChangeInAssetRetirementObligationTableTextBlock_AC8B3AAE06CADD4D353121779BB02811_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfChangeInAssetRetirementObligationTableTextBlock_AC8B3AAE06CADD4D353121779BB02811" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule of changes in asset retirement obligation</link:label>
    <link:label id="lab_us-gaap_ScheduleOfChangeInAssetRetirementObligationTableTextBlock_AC8B3AAE06CADD4D353121779BB02811_label_en-US" xlink:label="lab_us-gaap_ScheduleOfChangeInAssetRetirementObligationTableTextBlock_AC8B3AAE06CADD4D353121779BB02811" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Change in Asset Retirement Obligation [Table Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ScheduleOfChangeInAssetRetirementObligationTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfChangeInAssetRetirementObligationTableTextBlock_AC8B3AAE06CADD4D353121779BB02811" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfChangeInAssetRetirementObligationTableTextBlock_AC8B3AAE06CADD4D353121779BB02811" xlink:to="lab_us-gaap_ScheduleOfChangeInAssetRetirementObligationTableTextBlock_AC8B3AAE06CADD4D353121779BB02811" xlink:type="arc" />
    <link:label id="lab_us-gaap_ScheduleOfSaleLeasebackTransactionsTextBlock_F16E8DC17B2BF88AAB5A21779BB00942_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfSaleLeasebackTransactionsTextBlock_F16E8DC17B2BF88AAB5A21779BB00942" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule of deferred lease inducement assets</link:label>
    <link:label id="lab_us-gaap_ScheduleOfSaleLeasebackTransactionsTextBlock_F16E8DC17B2BF88AAB5A21779BB00942_label_en-US" xlink:label="lab_us-gaap_ScheduleOfSaleLeasebackTransactionsTextBlock_F16E8DC17B2BF88AAB5A21779BB00942" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Sale Leaseback Transactions [Table Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ScheduleOfSaleLeasebackTransactionsTextBlock" xlink:label="loc_us-gaap_ScheduleOfSaleLeasebackTransactionsTextBlock_F16E8DC17B2BF88AAB5A21779BB00942" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfSaleLeasebackTransactionsTextBlock_F16E8DC17B2BF88AAB5A21779BB00942" xlink:to="lab_us-gaap_ScheduleOfSaleLeasebackTransactionsTextBlock_F16E8DC17B2BF88AAB5A21779BB00942" xlink:type="arc" />
    <link:label id="lab_us-gaap_StatementOfCashFlowsAbstract_CF9E75A8B7874A665313EAA4713A51D3_label_en-US" xlink:label="lab_us-gaap_StatementOfCashFlowsAbstract_CF9E75A8B7874A665313EAA4713A51D3" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Statement of Cash Flows [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_StatementOfCashFlowsAbstract" xlink:label="loc_us-gaap_StatementOfCashFlowsAbstract_CF9E75A8B7874A665313EAA4713A51D3" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StatementOfCashFlowsAbstract_CF9E75A8B7874A665313EAA4713A51D3" xlink:to="lab_us-gaap_StatementOfCashFlowsAbstract_CF9E75A8B7874A665313EAA4713A51D3" xlink:type="arc" />
    <link:label id="lab_us-gaap_CashAndCashEquivalentsPeriodIncreaseDecreaseAbstract_DF9015B704F7812DD44CEAA4713A80D6_verboseLabel_en-US" xlink:label="lab_us-gaap_CashAndCashEquivalentsPeriodIncreaseDecreaseAbstract_DF9015B704F7812DD44CEAA4713A80D6" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Cash (used in) provided by:</link:label>
    <link:label id="lab_us-gaap_CashAndCashEquivalentsPeriodIncreaseDecreaseAbstract_DF9015B704F7812DD44CEAA4713A80D6_label_en-US" xlink:label="lab_us-gaap_CashAndCashEquivalentsPeriodIncreaseDecreaseAbstract_DF9015B704F7812DD44CEAA4713A80D6" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Cash and Cash Equivalents, Period Increase (Decrease) [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_CashAndCashEquivalentsPeriodIncreaseDecreaseAbstract" xlink:label="loc_us-gaap_CashAndCashEquivalentsPeriodIncreaseDecreaseAbstract_DF9015B704F7812DD44CEAA4713A80D6" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CashAndCashEquivalentsPeriodIncreaseDecreaseAbstract_DF9015B704F7812DD44CEAA4713A80D6" xlink:to="lab_us-gaap_CashAndCashEquivalentsPeriodIncreaseDecreaseAbstract_DF9015B704F7812DD44CEAA4713A80D6" xlink:type="arc" />
    <link:label id="lab_us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract_F92743EC507A2C06847DEAA4713AC047_verboseLabel_en-US" xlink:label="lab_us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract_F92743EC507A2C06847DEAA4713AC047" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Operating activities:</link:label>
    <link:label id="lab_us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract_F92743EC507A2C06847DEAA4713AC047_label_en-US" xlink:label="lab_us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract_F92743EC507A2C06847DEAA4713AC047" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Net Cash Provided by (Used in) Operating Activities [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract" xlink:label="loc_us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract_F92743EC507A2C06847DEAA4713AC047" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract_F92743EC507A2C06847DEAA4713AC047" xlink:to="lab_us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract_F92743EC507A2C06847DEAA4713AC047" xlink:type="arc" />
    <link:label id="lab_us-gaap_IncomeLossFromContinuingOperations_D178C6DE3839C9589826EAA4713A75F3_terseLabel_en-US" xlink:label="lab_us-gaap_IncomeLossFromContinuingOperations_D178C6DE3839C9589826EAA4713A75F3" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Net loss from continuing operations</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_IncomeLossFromContinuingOperations" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperations_D178C6DE3839C9589826EAA4713A75F3" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncomeLossFromContinuingOperations_D178C6DE3839C9589826EAA4713A75F3" xlink:to="lab_us-gaap_IncomeLossFromContinuingOperations_D178C6DE3839C9589826EAA4713A75F3" xlink:type="arc" />
    <link:label id="lab_us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperationsAbstract_23F2B22305D5BC9A6F3FEAA4713AF63C_verboseLabel_en-US" xlink:label="lab_us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperationsAbstract_23F2B22305D5BC9A6F3FEAA4713AF63C" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Adjustments to reconcile to net cash from operating activities:</link:label>
    <link:label id="lab_us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperationsAbstract_23F2B22305D5BC9A6F3FEAA4713AF63C_label_en-US" xlink:label="lab_us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperationsAbstract_23F2B22305D5BC9A6F3FEAA4713AF63C" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Net Cash Provided by (Used in) Operating Activities, Continuing Operations [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperationsAbstract" xlink:label="loc_us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperationsAbstract_23F2B22305D5BC9A6F3FEAA4713AF63C" xlink:type="locator" />
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    <link:label id="lab_us-gaap_DepreciationAndAmortization_F43FAC4FB0EF76D0CE4EEAA4713B00C1_verboseLabel_en-US" xlink:label="lab_us-gaap_DepreciationAndAmortization_F43FAC4FB0EF76D0CE4EEAA4713B00C1" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Depreciation</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_DepreciationAndAmortization" xlink:label="loc_us-gaap_DepreciationAndAmortization_F43FAC4FB0EF76D0CE4EEAA4713B00C1" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DepreciationAndAmortization_F43FAC4FB0EF76D0CE4EEAA4713B00C1" xlink:to="lab_us-gaap_DepreciationAndAmortization_F43FAC4FB0EF76D0CE4EEAA4713B00C1" xlink:type="arc" />
    <link:label id="lab_us-gaap_AmortizationOfFinancingCosts_9879C857C56E764459BFEAA4713B16B0_verboseLabel_en-US" xlink:label="lab_us-gaap_AmortizationOfFinancingCosts_9879C857C56E764459BFEAA4713B16B0" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Amortization of deferred financing costs (note 11(c))</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_AmortizationOfFinancingCosts" xlink:label="loc_us-gaap_AmortizationOfFinancingCosts_9879C857C56E764459BFEAA4713B16B0" xlink:type="locator" />
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    <link:label id="lab_noa_PaymentsofLeaseInducements_67114E1172E64044AE82EAA4713B8BC5_negatedTerseLabel_en-US" xlink:label="lab_noa_PaymentsofLeaseInducements_67114E1172E64044AE82EAA4713B8BC5" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Lease inducement paid on sublease</link:label>
    <link:label id="lab_noa_PaymentsofLeaseInducements_67114E1172E64044AE82EAA4713B8BC5_label_en-US" xlink:label="lab_noa_PaymentsofLeaseInducements_67114E1172E64044AE82EAA4713B8BC5" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Payments of Lease Inducements</link:label>
    <link:label id="lab_noa_PaymentsofLeaseInducements_67114E1172E64044AE82EAA4713B8BC5_documentation_en-US" xlink:label="lab_noa_PaymentsofLeaseInducements_67114E1172E64044AE82EAA4713B8BC5" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Payments of Lease Inducements</link:label>
    <link:loc xlink:href="noa-20151231.xsd#noa_PaymentsofLeaseInducements" xlink:label="loc_noa_PaymentsofLeaseInducements_67114E1172E64044AE82EAA4713B8BC5" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_noa_PaymentsofLeaseInducements_67114E1172E64044AE82EAA4713B8BC5" xlink:to="lab_noa_PaymentsofLeaseInducements_67114E1172E64044AE82EAA4713B8BC5" xlink:type="arc" />
    <link:label id="lab_us-gaap_GainLossOnDispositionOfAssets_257D9184EFD674481C0BEAA4713B61F1_negatedTerseLabel_en-US" xlink:label="lab_us-gaap_GainLossOnDispositionOfAssets_257D9184EFD674481C0BEAA4713B61F1" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Gain (loss) on disposal of assets held for sale (note 8)</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_GainLossOnDispositionOfAssets" xlink:label="loc_us-gaap_GainLossOnDispositionOfAssets_257D9184EFD674481C0BEAA4713B61F1" xlink:type="locator" />
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    <link:label id="lab_us-gaap_UnrealizedGainLossOnDerivatives_D2B6D143FC5CA64EB861EAA4713B3FF9_verboseLabel_en-US" xlink:label="lab_us-gaap_UnrealizedGainLossOnDerivatives_D2B6D143FC5CA64EB861EAA4713B3FF9" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Unrealized gain on derivative financial instruments</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_UnrealizedGainLossOnDerivatives" xlink:label="loc_us-gaap_UnrealizedGainLossOnDerivatives_D2B6D143FC5CA64EB861EAA4713B3FF9" xlink:type="locator" />
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    <link:label id="lab_us-gaap_ShareBasedCompensation_0F26443E3876C92EF394EAA4713B5A80_verboseLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensation_0F26443E3876C92EF394EAA4713B5A80" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Stock-based compensation expense (note 22(a))</link:label>
    <link:label id="lab_us-gaap_ShareBasedCompensation_0F26443E3876C92EF394EAA4713B5A80_label_en-US" xlink:label="lab_us-gaap_ShareBasedCompensation_0F26443E3876C92EF394EAA4713B5A80" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ShareBasedCompensation" xlink:label="loc_us-gaap_ShareBasedCompensation_0F26443E3876C92EF394EAA4713B5A80" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensation_0F26443E3876C92EF394EAA4713B5A80" xlink:to="lab_us-gaap_ShareBasedCompensation_0F26443E3876C92EF394EAA4713B5A80" xlink:type="arc" />
    <link:label id="lab_noa_CashSettlementOfRestrictedShareUnitPlan_716427D66820B2971982EAA4713C05EE_negatedLabel_en-US" xlink:label="lab_noa_CashSettlementOfRestrictedShareUnitPlan_716427D66820B2971982EAA4713C05EE" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Cash settlement of stock-based compensation (note 23(d(i)) and 23(f(i)))</link:label>
    <link:label id="lab_noa_CashSettlementOfRestrictedShareUnitPlan_716427D66820B2971982EAA4713C05EE_label_en-US" xlink:label="lab_noa_CashSettlementOfRestrictedShareUnitPlan_716427D66820B2971982EAA4713C05EE" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Cash Settlement Of Restricted Share Unit Plan</link:label>
    <link:label id="lab_noa_CashSettlementOfRestrictedShareUnitPlan_716427D66820B2971982EAA4713C05EE_documentation_en-US" xlink:label="lab_noa_CashSettlementOfRestrictedShareUnitPlan_716427D66820B2971982EAA4713C05EE" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Cash Settlement Of Restricted Share Unit Plan</link:label>
    <link:loc xlink:href="noa-20151231.xsd#noa_CashSettlementOfRestrictedShareUnitPlan" xlink:label="loc_noa_CashSettlementOfRestrictedShareUnitPlan_716427D66820B2971982EAA4713C05EE" xlink:type="locator" />
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    <link:label id="lab_noa_PaymentstoSettleSharebasedPaymentAward_0A366720084AF60F1CADEAA4713C7065_negatedLabel_en-US" xlink:label="lab_noa_PaymentstoSettleSharebasedPaymentAward_0A366720084AF60F1CADEAA4713C7065" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Other adjustments to cash from operating activities (note 11(d), 16(b) and 16(c))</link:label>
    <link:label id="lab_noa_PaymentstoSettleSharebasedPaymentAward_0A366720084AF60F1CADEAA4713C7065_label_en-US" xlink:label="lab_noa_PaymentstoSettleSharebasedPaymentAward_0A366720084AF60F1CADEAA4713C7065" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Payments to Settle Share-based Payment Award</link:label>
    <link:label id="lab_noa_PaymentstoSettleSharebasedPaymentAward_0A366720084AF60F1CADEAA4713C7065_documentation_en-US" xlink:label="lab_noa_PaymentstoSettleSharebasedPaymentAward_0A366720084AF60F1CADEAA4713C7065" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Payments to Settle Share-based Payment Award</link:label>
    <link:loc xlink:href="noa-20151231.xsd#noa_PaymentstoSettleSharebasedPaymentAward" xlink:label="loc_noa_PaymentstoSettleSharebasedPaymentAward_0A366720084AF60F1CADEAA4713C7065" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_noa_PaymentstoSettleSharebasedPaymentAward_0A366720084AF60F1CADEAA4713C7065" xlink:to="lab_noa_PaymentstoSettleSharebasedPaymentAward_0A366720084AF60F1CADEAA4713C7065" xlink:type="arc" />
    <link:label id="lab_us-gaap_DeferredIncomeTaxExpenseBenefit_C3ACFEBB125CCF098FE9EAA4713C185A_verboseLabel_en-US" xlink:label="lab_us-gaap_DeferredIncomeTaxExpenseBenefit_C3ACFEBB125CCF098FE9EAA4713C185A" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Deferred income tax (benefit) expense (note 9)</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_DeferredIncomeTaxExpenseBenefit" xlink:label="loc_us-gaap_DeferredIncomeTaxExpenseBenefit_C3ACFEBB125CCF098FE9EAA4713C185A" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredIncomeTaxExpenseBenefit_C3ACFEBB125CCF098FE9EAA4713C185A" xlink:to="lab_us-gaap_DeferredIncomeTaxExpenseBenefit_C3ACFEBB125CCF098FE9EAA4713C185A" xlink:type="arc" />
    <link:label id="lab_us-gaap_IncreaseDecreaseInOperatingCapital_315D2310C76E179B382FEAA4713C1C55_negatedLabel_en-US" xlink:label="lab_us-gaap_IncreaseDecreaseInOperatingCapital_315D2310C76E179B382FEAA4713C1C55" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Net changes in non-cash working capital (note 23(b))</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_IncreaseDecreaseInOperatingCapital" xlink:label="loc_us-gaap_IncreaseDecreaseInOperatingCapital_315D2310C76E179B382FEAA4713C1C55" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncreaseDecreaseInOperatingCapital_315D2310C76E179B382FEAA4713C1C55" xlink:to="lab_us-gaap_IncreaseDecreaseInOperatingCapital_315D2310C76E179B382FEAA4713C1C55" xlink:type="arc" />
    <link:label id="lab_us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperations_B50CBDB59A82DC90A8E3EAA4713CB18F_totalLabel_en-US" xlink:label="lab_us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperations_B50CBDB59A82DC90A8E3EAA4713CB18F" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Total operating activities</link:label>
    <link:label id="lab_us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperations_B50CBDB59A82DC90A8E3EAA4713CB18F_label_en-US" xlink:label="lab_us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperations_B50CBDB59A82DC90A8E3EAA4713CB18F" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Net Cash Provided by (Used in) Operating Activities, Continuing Operations</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperations" xlink:label="loc_us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperations_B50CBDB59A82DC90A8E3EAA4713CB18F" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperations_B50CBDB59A82DC90A8E3EAA4713CB18F" xlink:to="lab_us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperations_B50CBDB59A82DC90A8E3EAA4713CB18F" xlink:type="arc" />
    <link:label id="lab_us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_4786DBF7ED429D1D10F0EAA4713C1106_verboseLabel_en-US" xlink:label="lab_us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_4786DBF7ED429D1D10F0EAA4713C1106" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Investing activities:</link:label>
    <link:label id="lab_us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_4786DBF7ED429D1D10F0EAA4713C1106_label_en-US" xlink:label="lab_us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_4786DBF7ED429D1D10F0EAA4713C1106" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Net Cash Provided by (Used in) Investing Activities [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract" xlink:label="loc_us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_4786DBF7ED429D1D10F0EAA4713C1106" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_4786DBF7ED429D1D10F0EAA4713C1106" xlink:to="lab_us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_4786DBF7ED429D1D10F0EAA4713C1106" xlink:type="arc" />
    <link:label id="lab_us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_5D84595142A7F84F25D7EAA4713C2D6B_negatedLabel_en-US" xlink:label="lab_us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_5D84595142A7F84F25D7EAA4713C2D6B" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Purchase of plant and equipment</link:label>
    <link:label id="lab_us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_5D84595142A7F84F25D7EAA4713C2D6B_label_en-US" xlink:label="lab_us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_5D84595142A7F84F25D7EAA4713C2D6B" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Payments to Acquire Property, Plant, and Equipment</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_PaymentsToAcquirePropertyPlantAndEquipment" xlink:label="loc_us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_5D84595142A7F84F25D7EAA4713C2D6B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_5D84595142A7F84F25D7EAA4713C2D6B" xlink:to="lab_us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_5D84595142A7F84F25D7EAA4713C2D6B" xlink:type="arc" />
    <link:label id="lab_us-gaap_PaymentsToAcquireIntangibleAssets_29D7BB0C53E3EDAC1A1EEAA4713CEC19_negatedLabel_en-US" xlink:label="lab_us-gaap_PaymentsToAcquireIntangibleAssets_29D7BB0C53E3EDAC1A1EEAA4713CEC19" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Additions to intangible assets (note 11(b))</link:label>
    <link:label id="lab_us-gaap_PaymentsToAcquireIntangibleAssets_29D7BB0C53E3EDAC1A1EEAA4713CEC19_label_en-US" xlink:label="lab_us-gaap_PaymentsToAcquireIntangibleAssets_29D7BB0C53E3EDAC1A1EEAA4713CEC19" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Payments to Acquire Intangible Assets</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_PaymentsToAcquireIntangibleAssets" xlink:label="loc_us-gaap_PaymentsToAcquireIntangibleAssets_29D7BB0C53E3EDAC1A1EEAA4713CEC19" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PaymentsToAcquireIntangibleAssets_29D7BB0C53E3EDAC1A1EEAA4713CEC19" xlink:to="lab_us-gaap_PaymentsToAcquireIntangibleAssets_29D7BB0C53E3EDAC1A1EEAA4713CEC19" xlink:type="arc" />
    <link:label id="lab_us-gaap_ProceedsFromSaleOfPropertyPlantAndEquipment_BD6681D29D594D6F1B14EAA4713CDA35_verboseLabel_en-US" xlink:label="lab_us-gaap_ProceedsFromSaleOfPropertyPlantAndEquipment_BD6681D29D594D6F1B14EAA4713CDA35" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Proceeds on disposal of plant and equipment</link:label>
    <link:label id="lab_us-gaap_ProceedsFromSaleOfPropertyPlantAndEquipment_BD6681D29D594D6F1B14EAA4713CDA35_label_en-US" xlink:label="lab_us-gaap_ProceedsFromSaleOfPropertyPlantAndEquipment_BD6681D29D594D6F1B14EAA4713CDA35" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Proceeds from Sale of Property, Plant, and Equipment</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ProceedsFromSaleOfPropertyPlantAndEquipment" xlink:label="loc_us-gaap_ProceedsFromSaleOfPropertyPlantAndEquipment_BD6681D29D594D6F1B14EAA4713CDA35" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ProceedsFromSaleOfPropertyPlantAndEquipment_BD6681D29D594D6F1B14EAA4713CDA35" xlink:to="lab_us-gaap_ProceedsFromSaleOfPropertyPlantAndEquipment_BD6681D29D594D6F1B14EAA4713CDA35" xlink:type="arc" />
    <link:label id="lab_noa_ProceedsFromDisposalOfPropertyHeldForSale_885DC8A8E2FC3B7E6E27EAA4713C9DF5_verboseLabel_en-US" xlink:label="lab_noa_ProceedsFromDisposalOfPropertyHeldForSale_885DC8A8E2FC3B7E6E27EAA4713C9DF5" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Proceeds on disposal of assets held for sale</link:label>
    <link:label id="lab_noa_ProceedsFromDisposalOfPropertyHeldForSale_885DC8A8E2FC3B7E6E27EAA4713C9DF5_label_en-US" xlink:label="lab_noa_ProceedsFromDisposalOfPropertyHeldForSale_885DC8A8E2FC3B7E6E27EAA4713C9DF5" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Proceeds from Disposal of Property Held for Sale</link:label>
    <link:label id="lab_noa_ProceedsFromDisposalOfPropertyHeldForSale_885DC8A8E2FC3B7E6E27EAA4713C9DF5_documentation_en-US" xlink:label="lab_noa_ProceedsFromDisposalOfPropertyHeldForSale_885DC8A8E2FC3B7E6E27EAA4713C9DF5" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Proceeds on disposal of assets held for sale</link:label>
    <link:loc xlink:href="noa-20151231.xsd#noa_ProceedsFromDisposalOfPropertyHeldForSale" xlink:label="loc_noa_ProceedsFromDisposalOfPropertyHeldForSale_885DC8A8E2FC3B7E6E27EAA4713C9DF5" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_noa_ProceedsFromDisposalOfPropertyHeldForSale_885DC8A8E2FC3B7E6E27EAA4713C9DF5" xlink:to="lab_noa_ProceedsFromDisposalOfPropertyHeldForSale_885DC8A8E2FC3B7E6E27EAA4713C9DF5" xlink:type="arc" />
    <link:label id="lab_us-gaap_NetCashProvidedByUsedInInvestingActivitiesContinuingOperations_DFC1540B73A7F15199B5EAA4713D2D57_totalLabel_en-US" xlink:label="lab_us-gaap_NetCashProvidedByUsedInInvestingActivitiesContinuingOperations_DFC1540B73A7F15199B5EAA4713D2D57" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Total investing activities</link:label>
    <link:label id="lab_us-gaap_NetCashProvidedByUsedInInvestingActivitiesContinuingOperations_DFC1540B73A7F15199B5EAA4713D2D57_label_en-US" xlink:label="lab_us-gaap_NetCashProvidedByUsedInInvestingActivitiesContinuingOperations_DFC1540B73A7F15199B5EAA4713D2D57" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Net Cash Provided by (Used in) Investing Activities, Continuing Operations</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_NetCashProvidedByUsedInInvestingActivitiesContinuingOperations" xlink:label="loc_us-gaap_NetCashProvidedByUsedInInvestingActivitiesContinuingOperations_DFC1540B73A7F15199B5EAA4713D2D57" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivitiesContinuingOperations_DFC1540B73A7F15199B5EAA4713D2D57" xlink:to="lab_us-gaap_NetCashProvidedByUsedInInvestingActivitiesContinuingOperations_DFC1540B73A7F15199B5EAA4713D2D57" xlink:type="arc" />
    <link:label id="lab_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_822BB393E52A64968CAAEAA4713D7D23_verboseLabel_en-US" xlink:label="lab_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_822BB393E52A64968CAAEAA4713D7D23" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Financing activities:</link:label>
    <link:label id="lab_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_822BB393E52A64968CAAEAA4713D7D23_label_en-US" xlink:label="lab_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_822BB393E52A64968CAAEAA4713D7D23" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Net Cash Provided by (Used in) Financing Activities [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract" xlink:label="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_822BB393E52A64968CAAEAA4713D7D23" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_822BB393E52A64968CAAEAA4713D7D23" xlink:to="lab_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_822BB393E52A64968CAAEAA4713D7D23" xlink:type="arc" />
    <link:label id="lab_us-gaap_RepaymentsOfLongTermLinesOfCredit_08C7457605B16A96E8BFEAA4713DA3B4_negatedLabel_en-US" xlink:label="lab_us-gaap_RepaymentsOfLongTermLinesOfCredit_08C7457605B16A96E8BFEAA4713DA3B4" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Repayment of Credit Facilities</link:label>
    <link:label id="lab_us-gaap_RepaymentsOfLongTermLinesOfCredit_08C7457605B16A96E8BFEAA4713DA3B4_label_en-US" xlink:label="lab_us-gaap_RepaymentsOfLongTermLinesOfCredit_08C7457605B16A96E8BFEAA4713DA3B4" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Repayments of Long-term Lines of Credit</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_RepaymentsOfLongTermLinesOfCredit" xlink:label="loc_us-gaap_RepaymentsOfLongTermLinesOfCredit_08C7457605B16A96E8BFEAA4713DA3B4" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RepaymentsOfLongTermLinesOfCredit_08C7457605B16A96E8BFEAA4713DA3B4" xlink:to="lab_us-gaap_RepaymentsOfLongTermLinesOfCredit_08C7457605B16A96E8BFEAA4713DA3B4" xlink:type="arc" />
    <link:label id="lab_us-gaap_ProceedsFromLongTermLinesOfCredit_1446F90CB1D22D97C218EAA4713D9B68_verboseLabel_en-US" xlink:label="lab_us-gaap_ProceedsFromLongTermLinesOfCredit_1446F90CB1D22D97C218EAA4713D9B68" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Increase in Credit Facilities</link:label>
    <link:label id="lab_us-gaap_ProceedsFromLongTermLinesOfCredit_1446F90CB1D22D97C218EAA4713D9B68_label_en-US" xlink:label="lab_us-gaap_ProceedsFromLongTermLinesOfCredit_1446F90CB1D22D97C218EAA4713D9B68" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Proceeds from Long-term Lines of Credit</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ProceedsFromLongTermLinesOfCredit" xlink:label="loc_us-gaap_ProceedsFromLongTermLinesOfCredit_1446F90CB1D22D97C218EAA4713D9B68" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ProceedsFromLongTermLinesOfCredit_1446F90CB1D22D97C218EAA4713D9B68" xlink:to="lab_us-gaap_ProceedsFromLongTermLinesOfCredit_1446F90CB1D22D97C218EAA4713D9B68" xlink:type="arc" />
    <link:label id="lab_us-gaap_PaymentsOfFinancingCosts_9F7EA54D587A848F3D85EAA4713D1F28_negatedLabel_en-US" xlink:label="lab_us-gaap_PaymentsOfFinancingCosts_9F7EA54D587A848F3D85EAA4713D1F28" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Financing costs (note 11(c))</link:label>
    <link:label id="lab_us-gaap_PaymentsOfFinancingCosts_9F7EA54D587A848F3D85EAA4713D1F28_label_en-US" xlink:label="lab_us-gaap_PaymentsOfFinancingCosts_9F7EA54D587A848F3D85EAA4713D1F28" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Payments of Financing Costs</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_PaymentsOfFinancingCosts" xlink:label="loc_us-gaap_PaymentsOfFinancingCosts_9F7EA54D587A848F3D85EAA4713D1F28" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PaymentsOfFinancingCosts_9F7EA54D587A848F3D85EAA4713D1F28" xlink:to="lab_us-gaap_PaymentsOfFinancingCosts_9F7EA54D587A848F3D85EAA4713D1F28" xlink:type="arc" />
    <link:label id="lab_us-gaap_RepaymentsOfSeniorDebt_901A381913265C1EBA4EEAA4713D5604_negatedLabel_en-US" xlink:label="lab_us-gaap_RepaymentsOfSeniorDebt_901A381913265C1EBA4EEAA4713D5604" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Redemption of Series 1 Debentures (note 13(c))</link:label>
    <link:label id="lab_us-gaap_RepaymentsOfSeniorDebt_901A381913265C1EBA4EEAA4713D5604_label_en-US" xlink:label="lab_us-gaap_RepaymentsOfSeniorDebt_901A381913265C1EBA4EEAA4713D5604" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Repayments of Senior Debt</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_RepaymentsOfSeniorDebt" xlink:label="loc_us-gaap_RepaymentsOfSeniorDebt_901A381913265C1EBA4EEAA4713D5604" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RepaymentsOfSeniorDebt_901A381913265C1EBA4EEAA4713D5604" xlink:to="lab_us-gaap_RepaymentsOfSeniorDebt_901A381913265C1EBA4EEAA4713D5604" xlink:type="arc" />
    <link:label id="lab_us-gaap_RepaymentsOfLongTermCapitalLeaseObligations_89E8277AC003B42EC5ADEAA4713D4D3A_negatedLabel_en-US" xlink:label="lab_us-gaap_RepaymentsOfLongTermCapitalLeaseObligations_89E8277AC003B42EC5ADEAA4713D4D3A" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Repayment of capital lease obligations</link:label>
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    <link:label id="lab_us-gaap_ProceedsFromStockOptionsExercised_7C0F32DEBC1563EB1518EAA4713D1D86_label_en-US" xlink:label="lab_us-gaap_ProceedsFromStockOptionsExercised_7C0F32DEBC1563EB1518EAA4713D1D86" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Proceeds from Stock Options Exercised</link:label>
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    <link:label id="lab_us-gaap_PaymentsOfDividends_D1CFA3C5F2EA6A41ED4FEAA4713D97B1_label_en-US" xlink:label="lab_us-gaap_PaymentsOfDividends_D1CFA3C5F2EA6A41ED4FEAA4713D97B1" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Payments of Dividends</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_PaymentsOfDividends" xlink:label="loc_us-gaap_PaymentsOfDividends_D1CFA3C5F2EA6A41ED4FEAA4713D97B1" xlink:type="locator" />
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    <link:label id="lab_noa_PaymentsforRepurchaseofCommonStockUnitSettlement_2DA697D2C4244B2355ADEAA4713E4CC9_negatedTerseLabel_en-US" xlink:label="lab_noa_PaymentsforRepurchaseofCommonStockUnitSettlement_2DA697D2C4244B2355ADEAA4713E4CC9" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Purchase of treasury shares for settlement of certain equity classified stock-based compensation (note 17(a))</link:label>
    <link:label id="lab_noa_PaymentsforRepurchaseofCommonStockUnitSettlement_2DA697D2C4244B2355ADEAA4713E4CC9_label_en-US" xlink:label="lab_noa_PaymentsforRepurchaseofCommonStockUnitSettlement_2DA697D2C4244B2355ADEAA4713E4CC9" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Payments for Repurchase of Common Stock, Unit Settlement</link:label>
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    <link:label id="lab_us-gaap_PaymentsForRepurchaseOfCommonStock_32F43B983AD65691A7F0EAA4713E0004_negatedTerseLabel_en-US" xlink:label="lab_us-gaap_PaymentsForRepurchaseOfCommonStock_32F43B983AD65691A7F0EAA4713E0004" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Share purchase programs (note 17(c))</link:label>
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    <link:label id="lab_us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperations_D956E8EBA0A69DFE20E9EAA4713E79FD_totalLabel_en-US" xlink:label="lab_us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperations_D956E8EBA0A69DFE20E9EAA4713E79FD" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Total financing activities</link:label>
    <link:label id="lab_us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperations_D956E8EBA0A69DFE20E9EAA4713E79FD_label_en-US" xlink:label="lab_us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperations_D956E8EBA0A69DFE20E9EAA4713E79FD" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Net Cash Provided by (Used in) Financing Activities, Continuing Operations</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperations" xlink:label="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperations_D956E8EBA0A69DFE20E9EAA4713E79FD" xlink:type="locator" />
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    <link:label id="lab_us-gaap_NetCashProvidedByUsedInContinuingOperations_7EADD3E68621641F6EE8EAA4713E50CC_label_en-US" xlink:label="lab_us-gaap_NetCashProvidedByUsedInContinuingOperations_7EADD3E68621641F6EE8EAA4713E50CC" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Net Cash Provided by (Used in) Continuing Operations</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_NetCashProvidedByUsedInContinuingOperations" xlink:label="loc_us-gaap_NetCashProvidedByUsedInContinuingOperations_7EADD3E68621641F6EE8EAA4713E50CC" xlink:type="locator" />
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    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_CashProvidedByUsedInOperatingActivitiesDiscontinuedOperations" xlink:label="loc_us-gaap_CashProvidedByUsedInOperatingActivitiesDiscontinuedOperations_000C9668F7192DF8E09FEAA4713E2483" xlink:type="locator" />
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    <link:label id="lab_us-gaap_CashProvidedByUsedInInvestingActivitiesDiscontinuedOperations_DABC5AC67F5DB601DFF4EAA4713E7942_terseLabel_en-US" xlink:label="lab_us-gaap_CashProvidedByUsedInInvestingActivitiesDiscontinuedOperations_DABC5AC67F5DB601DFF4EAA4713E7942" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Investing activities</link:label>
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    <link:label id="lab_us-gaap_CashProvidedByUsedInFinancingActivitiesDiscontinuedOperations_7F316245689B04706EF6EAA4713EA0C3_terseLabel_en-US" xlink:label="lab_us-gaap_CashProvidedByUsedInFinancingActivitiesDiscontinuedOperations_7F316245689B04706EF6EAA4713EA0C3" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Financing activities</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_CashProvidedByUsedInFinancingActivitiesDiscontinuedOperations" xlink:label="loc_us-gaap_CashProvidedByUsedInFinancingActivitiesDiscontinuedOperations_7F316245689B04706EF6EAA4713EA0C3" xlink:type="locator" />
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    <link:label id="lab_us-gaap_LongTermDebtCurrent_20ECA394903BEA5A174CCC4525C4E59F_terseLabel_en-US" xlink:label="lab_us-gaap_LongTermDebtCurrent_20ECA394903BEA5A174CCC4525C4E59F" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Current portion of long term debt (note 13(a))</link:label>
    <link:label id="lab_us-gaap_LongTermDebtCurrent_20ECA394903BEA5A174CCC4525C4E59F_label_en-US" xlink:label="lab_us-gaap_LongTermDebtCurrent_20ECA394903BEA5A174CCC4525C4E59F" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Long-term Debt, Current Maturities</link:label>
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    <link:label id="lab_us-gaap_LongTermDebtNoncurrent_D3EAF9813C7EFA187C04CC41BB505103_label_en-US" xlink:label="lab_us-gaap_LongTermDebtNoncurrent_D3EAF9813C7EFA187C04CC41BB505103" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Long-term Debt, Excluding Current Maturities</link:label>
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    <link:label id="lab_noa_ScheduleOfContractClaimsRevenueTableTextBlock_AE8AE6BEF315D0FBDA9621779D12AED4_terseLabel_en-US" xlink:label="lab_noa_ScheduleOfContractClaimsRevenueTableTextBlock_AE8AE6BEF315D0FBDA9621779D12AED4" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule of claims revenue</link:label>
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    <link:label id="lab_us-gaap_PrepaidExpenseCurrentAbstract_F78284D7A9779CADC83E21779D1FA324_terseLabel_en-US" xlink:label="lab_us-gaap_PrepaidExpenseCurrentAbstract_F78284D7A9779CADC83E21779D1FA324" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Current:</link:label>
    <link:label id="lab_us-gaap_PrepaidExpenseCurrentAbstract_F78284D7A9779CADC83E21779D1FA324_label_en-US" xlink:label="lab_us-gaap_PrepaidExpenseCurrentAbstract_F78284D7A9779CADC83E21779D1FA324" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Prepaid Expense, Current [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_PrepaidExpenseCurrentAbstract" xlink:label="loc_us-gaap_PrepaidExpenseCurrentAbstract_F78284D7A9779CADC83E21779D1FA324" xlink:type="locator" />
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    <link:label id="lab_us-gaap_PrepaidRent_1FD0300F9DF2D6DC750121779D208117_terseLabel_en-US" xlink:label="lab_us-gaap_PrepaidRent_1FD0300F9DF2D6DC750121779D208117" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Prepaid lease payments</link:label>
    <link:label id="lab_us-gaap_PrepaidRent_1FD0300F9DF2D6DC750121779D208117_label_en-US" xlink:label="lab_us-gaap_PrepaidRent_1FD0300F9DF2D6DC750121779D208117" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Prepaid Rent</link:label>
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    <link:label id="lab_us-gaap_PrepaidInterest_172501D5CE947A1C05DB21779D20729F_terseLabel_en-US" xlink:label="lab_us-gaap_PrepaidInterest_172501D5CE947A1C05DB21779D20729F" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Prepaid interest</link:label>
    <link:label id="lab_us-gaap_PrepaidInterest_172501D5CE947A1C05DB21779D20729F_label_en-US" xlink:label="lab_us-gaap_PrepaidInterest_172501D5CE947A1C05DB21779D20729F" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Prepaid Interest</link:label>
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    <link:label id="lab_us-gaap_PrepaidExpenseCurrent_1695AA02E630C9BE79D221779D2026A0_totalLabel_en-US" xlink:label="lab_us-gaap_PrepaidExpenseCurrent_1695AA02E630C9BE79D221779D2026A0" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Prepaid expenses and deposits</link:label>
    <link:label id="lab_us-gaap_PrepaidExpenseCurrent_1695AA02E630C9BE79D221779D2026A0_label_en-US" xlink:label="lab_us-gaap_PrepaidExpenseCurrent_1695AA02E630C9BE79D221779D2026A0" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Prepaid Expense, Current</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_PrepaidExpenseCurrent" xlink:label="loc_us-gaap_PrepaidExpenseCurrent_1695AA02E630C9BE79D221779D2026A0" xlink:type="locator" />
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    <link:label id="lab_us-gaap_PrepaidExpenseNoncurrentAbstract_BAA500DD5E5DFE1556DC21779D213D4F_terseLabel_en-US" xlink:label="lab_us-gaap_PrepaidExpenseNoncurrentAbstract_BAA500DD5E5DFE1556DC21779D213D4F" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Long term:</link:label>
    <link:label id="lab_us-gaap_PrepaidExpenseNoncurrentAbstract_BAA500DD5E5DFE1556DC21779D213D4F_label_en-US" xlink:label="lab_us-gaap_PrepaidExpenseNoncurrentAbstract_BAA500DD5E5DFE1556DC21779D213D4F" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Prepaid Expense, Noncurrent [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_PrepaidExpenseNoncurrentAbstract" xlink:label="loc_us-gaap_PrepaidExpenseNoncurrentAbstract_BAA500DD5E5DFE1556DC21779D213D4F" xlink:type="locator" />
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    <link:label id="lab_noa_PrepaidRentNoncurrent_F6B3143C8E5FA18E4DE821779D21A741_terseLabel_en-US" xlink:label="lab_noa_PrepaidRentNoncurrent_F6B3143C8E5FA18E4DE821779D21A741" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Prepaid lease payments (note 11(a))</link:label>
    <link:loc xlink:href="noa-20151231.xsd#noa_PrepaidRentNoncurrent" xlink:label="loc_noa_PrepaidRentNoncurrent_F6B3143C8E5FA18E4DE821779D21A741" xlink:type="locator" />
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    <link:label id="lab_us-gaap_ScheduleOfEffectiveIncomeTaxRateReconciliationTableTextBlock_AD233D1412F5F0F10F3D21779D893C8D_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfEffectiveIncomeTaxRateReconciliationTableTextBlock_AD233D1412F5F0F10F3D21779D893C8D" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule of differences between tax provision and Federal and Provincial statutory income taxes</link:label>
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    <link:label id="lab_us-gaap_CreditFacilityAxis_FE7DBC15859340A77F36D25104186B4F_label_en-US" xlink:label="lab_us-gaap_CreditFacilityAxis_FE7DBC15859340A77F36D25104186B4F" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Credit Facility [Axis]</link:label>
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    <link:label id="lab_us-gaap_CreditFacilityDomain_7F890D5C5D7C441A6A10D251041854B7_terseLabel_en-US" xlink:label="lab_us-gaap_CreditFacilityDomain_7F890D5C5D7C441A6A10D251041854B7" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Credit Facility [Domain]</link:label>
    <link:label id="lab_us-gaap_CreditFacilityDomain_7F890D5C5D7C441A6A10D251041854B7_label_en-US" xlink:label="lab_us-gaap_CreditFacilityDomain_7F890D5C5D7C441A6A10D251041854B7" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Credit Facility [Domain]</link:label>
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    <link:label id="lab_noa_TermAndRevolvingCreditFacilitiesMember_215742FF70DD7F3D8D6DD25104187BB7_terseLabel_en-US" xlink:label="lab_noa_TermAndRevolvingCreditFacilitiesMember_215742FF70DD7F3D8D6DD25104187BB7" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Term and Revolving Credit Facilities</link:label>
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    <link:label id="lab_us-gaap_SecuredDebtMember_A9EB4CE870A3A73049C3D251041816C2_terseLabel_en-US" xlink:label="lab_us-gaap_SecuredDebtMember_A9EB4CE870A3A73049C3D251041816C2" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Secured Debt</link:label>
    <link:label id="lab_us-gaap_SecuredDebtMember_A9EB4CE870A3A73049C3D251041816C2_label_en-US" xlink:label="lab_us-gaap_SecuredDebtMember_A9EB4CE870A3A73049C3D251041816C2" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Secured Debt [Member]</link:label>
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    <link:label id="lab_us-gaap_RevolvingCreditFacilityMember_3B1DEB92ED5B44567F7ED25104186863_terseLabel_en-US" xlink:label="lab_us-gaap_RevolvingCreditFacilityMember_3B1DEB92ED5B44567F7ED25104186863" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Revolving Facility</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_RevolvingCreditFacilityMember" xlink:label="loc_us-gaap_RevolvingCreditFacilityMember_3B1DEB92ED5B44567F7ED25104186863" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RevolvingCreditFacilityMember_3B1DEB92ED5B44567F7ED25104186863" xlink:to="lab_us-gaap_RevolvingCreditFacilityMember_3B1DEB92ED5B44567F7ED25104186863" xlink:type="arc" />
    <link:label id="lab_us-gaap_LetterOfCreditMember_8DAC8CD72D0E4C530864D2510418797B_terseLabel_en-US" xlink:label="lab_us-gaap_LetterOfCreditMember_8DAC8CD72D0E4C530864D2510418797B" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Letter of Credit</link:label>
    <link:label id="lab_us-gaap_LetterOfCreditMember_8DAC8CD72D0E4C530864D2510418797B_label_en-US" xlink:label="lab_us-gaap_LetterOfCreditMember_8DAC8CD72D0E4C530864D2510418797B" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Letter of Credit [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_LetterOfCreditMember" xlink:label="loc_us-gaap_LetterOfCreditMember_8DAC8CD72D0E4C530864D2510418797B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LetterOfCreditMember_8DAC8CD72D0E4C530864D2510418797B" xlink:to="lab_us-gaap_LetterOfCreditMember_8DAC8CD72D0E4C530864D2510418797B" xlink:type="arc" />
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    <link:label id="lab_us-gaap_LineOfCreditFacilityLineItems_F89FB8E82412D46862D9D25104183B41_label_en-US" xlink:label="lab_us-gaap_LineOfCreditFacilityLineItems_F89FB8E82412D46862D9D25104183B41" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Line of Credit Facility [Line Items]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_LineOfCreditFacilityLineItems" xlink:label="loc_us-gaap_LineOfCreditFacilityLineItems_F89FB8E82412D46862D9D25104183B41" xlink:type="locator" />
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    <link:label id="lab_us-gaap_LineOfCredit_EAD076AC23AE898953EDD2510418CC9F_terseLabel_en-US" xlink:label="lab_us-gaap_LineOfCredit_EAD076AC23AE898953EDD2510418CC9F" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Long-term line of credit</link:label>
    <link:label id="lab_us-gaap_LineOfCredit_EAD076AC23AE898953EDD2510418CC9F_label_en-US" xlink:label="lab_us-gaap_LineOfCredit_EAD076AC23AE898953EDD2510418CC9F" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Long-term Line of Credit</link:label>
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    <link:label id="lab_us-gaap_LongTermLineOfCredit_258F674AFBD6969F4D7FD2527D3BFB8D_label_en-US" xlink:label="lab_us-gaap_LongTermLineOfCredit_258F674AFBD6969F4D7FD2527D3BFB8D" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Long-term Line of Credit, Noncurrent</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_LongTermLineOfCredit" xlink:label="loc_us-gaap_LongTermLineOfCredit_258F674AFBD6969F4D7FD2527D3BFB8D" xlink:type="locator" />
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    <link:label id="lab_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_F02E60F3CEB3D65F7391D2510418AC2F_label_en-US" xlink:label="lab_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_F02E60F3CEB3D65F7391D2510418AC2F" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Line of Credit Facility, Maximum Borrowing Capacity</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity" xlink:label="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_F02E60F3CEB3D65F7391D2510418AC2F" xlink:type="locator" />
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    <link:label id="lab_us-gaap_DebtInstrumentTerm_B781103BCC28BA9C99D4D2510418FF3F_terseLabel_en-US" xlink:label="lab_us-gaap_DebtInstrumentTerm_B781103BCC28BA9C99D4D2510418FF3F" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Amortization schedule for repayment</link:label>
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    <link:label id="lab_noa_DebtinstrumentRepaymentPercentofExcessCashFlow_970F4EE2CD7A874B98DAD2510418FF9B_terseLabel_en-US" xlink:label="lab_noa_DebtinstrumentRepaymentPercentofExcessCashFlow_970F4EE2CD7A874B98DAD2510418FF9B" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Repayment percentage of excess cash flow</link:label>
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    <link:label id="lab_us-gaap_LineOfCreditFacilityPeriodicPayment_DD6F02DB0D82FCB97AF5D2510418F7B9_terseLabel_en-US" xlink:label="lab_us-gaap_LineOfCreditFacilityPeriodicPayment_DD6F02DB0D82FCB97AF5D2510418F7B9" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Required scheduled payment</link:label>
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    <link:label id="lab_noa_DebtInstrumentRedemptionAuthorizedAmount_4EA9809B5C7DF38AFB94D2510418DD18_terseLabel_en-US" xlink:label="lab_noa_DebtInstrumentRedemptionAuthorizedAmount_4EA9809B5C7DF38AFB94D2510418DD18" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Debenture repurchase amount authorized</link:label>
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    <link:loc xlink:href="noa-20151231.xsd#noa_DebtInstrumentRedemptionAuthorizedAmount" xlink:label="loc_noa_DebtInstrumentRedemptionAuthorizedAmount_4EA9809B5C7DF38AFB94D2510418DD18" xlink:type="locator" />
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    <link:label id="lab_noa_DebtInstrumentCovenantTermsMaximumFaceValueOutstanding_2859321E75289E3885E3D2510419B2A0_terseLabel_en-US" xlink:label="lab_noa_DebtInstrumentCovenantTermsMaximumFaceValueOutstanding_2859321E75289E3885E3D2510419B2A0" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Debenture outstanding face amount of debt</link:label>
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    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate_265C8CB27879F216ACF3D2162E8B1400_terseLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate_265C8CB27879F216ACF3D2162E8B1400" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Dividend yield</link:label>
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    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate_265C8CB27879F216ACF3D2162E8B1400" xlink:type="locator" />
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    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsWeightedAverageVolatilityRate_FF4637AE5EA22B06FADFD2162E8BED6B_terseLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsWeightedAverageVolatilityRate_FF4637AE5EA22B06FADFD2162E8BED6B" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Expected volatility</link:label>
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsWeightedAverageVolatilityRate_FF4637AE5EA22B06FADFD2162E8BED6B_label_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsWeightedAverageVolatilityRate_FF4637AE5EA22B06FADFD2162E8BED6B" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Weighted Average Volatility Rate</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsWeightedAverageVolatilityRate" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsWeightedAverageVolatilityRate_FF4637AE5EA22B06FADFD2162E8BED6B" xlink:type="locator" />
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    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate_DE4A1DC65A735D64070FD2162E8BF206_terseLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate_DE4A1DC65A735D64070FD2162E8BF206" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Risk-free interest rate</link:label>
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    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate_DE4A1DC65A735D64070FD2162E8BF206" xlink:type="locator" />
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    <link:label id="lab_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1_DF3BB048B23F78A48E22D2162E8BEF16_terseLabel_en-US" xlink:label="lab_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1_DF3BB048B23F78A48E22D2162E8BEF16" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Expected life</link:label>
    <link:label id="lab_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1_DF3BB048B23F78A48E22D2162E8BEF16_label_en-US" xlink:label="lab_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1_DF3BB048B23F78A48E22D2162E8BEF16" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1" xlink:label="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1_DF3BB048B23F78A48E22D2162E8BEF16" xlink:type="locator" />
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    <link:label id="lab_us-gaap_AssetsAbstract_0ABCAD1684BB93708A29D216312B7EEC_verboseLabel_en-US" xlink:label="lab_us-gaap_AssetsAbstract_0ABCAD1684BB93708A29D216312B7EEC" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Assets</link:label>
    <link:label id="lab_us-gaap_AssetsAbstract_0ABCAD1684BB93708A29D216312B7EEC_label_en-US" xlink:label="lab_us-gaap_AssetsAbstract_0ABCAD1684BB93708A29D216312B7EEC" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Assets [Abstract]</link:label>
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    <link:label id="lab_us-gaap_AssetsCurrentAbstract_ADB365096A75E4632022D216312CF95D_verboseLabel_en-US" xlink:label="lab_us-gaap_AssetsCurrentAbstract_ADB365096A75E4632022D216312CF95D" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Current assets</link:label>
    <link:label id="lab_us-gaap_AssetsCurrentAbstract_ADB365096A75E4632022D216312CF95D_label_en-US" xlink:label="lab_us-gaap_AssetsCurrentAbstract_ADB365096A75E4632022D216312CF95D" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Assets, Current [Abstract]</link:label>
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    <link:label id="lab_us-gaap_CashAndCashEquivalentsAtCarryingValue_C91E31D12570E82CC39ED216312C4C1B_terseLabel_en-US" xlink:label="lab_us-gaap_CashAndCashEquivalentsAtCarryingValue_C91E31D12570E82CC39ED216312C4C1B" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Cash</link:label>
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    <link:label id="lab_us-gaap_AccountsAndOtherReceivablesNetCurrent_97F0E8A1973C1EE06125D216312C0117_verboseLabel_en-US" xlink:label="lab_us-gaap_AccountsAndOtherReceivablesNetCurrent_97F0E8A1973C1EE06125D216312C0117" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Accounts receivable, net (note 5 and 15(d))</link:label>
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    <link:label id="lab_us-gaap_UnbilledContractsReceivable_F40950155BD9D8BFE305D216312CBC27_verboseLabel_en-US" xlink:label="lab_us-gaap_UnbilledContractsReceivable_F40950155BD9D8BFE305D216312CBC27" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Unbilled revenue (note 6 and 15(d))</link:label>
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    <link:label id="lab_us-gaap_InventoryNet_DF17F3EF824DB22FB94CD216312C852F_verboseLabel_en-US" xlink:label="lab_us-gaap_InventoryNet_DF17F3EF824DB22FB94CD216312C852F" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Inventories</link:label>
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    <link:label id="lab_us-gaap_PrepaidExpenseCurrent_07F81D049A450966172CD216312C49D0_terseLabel_en-US" xlink:label="lab_us-gaap_PrepaidExpenseCurrent_07F81D049A450966172CD216312C49D0" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Prepaid expenses and deposits (note 7)</link:label>
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    <link:label id="lab_us-gaap_AssetsHeldForSaleNotPartOfDisposalGroupCurrent_6DFB00D8612A72CC5D43D216312CCE50_terseLabel_en-US" xlink:label="lab_us-gaap_AssetsHeldForSaleNotPartOfDisposalGroupCurrent_6DFB00D8612A72CC5D43D216312CCE50" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Assets held for sale (note 8 and 15(a))</link:label>
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    <link:label id="lab_us-gaap_AssetsCurrent_1F0F37C25C5A7F8298E5D216312C474D_totalLabel_en-US" xlink:label="lab_us-gaap_AssetsCurrent_1F0F37C25C5A7F8298E5D216312C474D" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Total current assets</link:label>
    <link:label id="lab_us-gaap_AssetsCurrent_1F0F37C25C5A7F8298E5D216312C474D_label_en-US" xlink:label="lab_us-gaap_AssetsCurrent_1F0F37C25C5A7F8298E5D216312C474D" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Assets, Current</link:label>
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    <link:label id="lab_us-gaap_PropertyPlantAndEquipmentNet_8A33BADB6D00BFCBD865D216312CC691_verboseLabel_en-US" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentNet_8A33BADB6D00BFCBD865D216312CC691" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Plant and equipment, net of accumulated depreciation of $188,398 and $173,537 (note 10)</link:label>
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    <link:label id="lab_us-gaap_OtherAssetsNoncurrent_00627556F7111512F0B3D216312CBC7D_verboseLabel_en-US" xlink:label="lab_us-gaap_OtherAssetsNoncurrent_00627556F7111512F0B3D216312CBC7D" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Other assets (note 11(a))</link:label>
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    <link:label id="lab_us-gaap_DeferredTaxAssetsLiabilitiesNetNoncurrent_0C70E53258C181C8F472D216312CD9F2_label_en-US" xlink:label="lab_us-gaap_DeferredTaxAssetsLiabilitiesNetNoncurrent_0C70E53258C181C8F472D216312CD9F2" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Tax Assets, Net, Noncurrent</link:label>
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    <link:label id="lab_us-gaap_Assets_00F91300E6003DB3F691D216312C5812_label_en-US" xlink:label="lab_us-gaap_Assets_00F91300E6003DB3F691D216312C5812" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Assets</link:label>
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    <link:label id="lab_us-gaap_LiabilitiesAndStockholdersEquityAbstract_35183E3EF35BACD61D89D216312C4CB3_label_en-US" xlink:label="lab_us-gaap_LiabilitiesAndStockholdersEquityAbstract_35183E3EF35BACD61D89D216312C4CB3" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Liabilities and Equity [Abstract]</link:label>
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    <link:label id="lab_us-gaap_LiabilitiesCurrentAbstract_13A27370C9FC3400BE5AD216312C3891_label_en-US" xlink:label="lab_us-gaap_LiabilitiesCurrentAbstract_13A27370C9FC3400BE5AD216312C3891" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Liabilities, Current [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_LiabilitiesCurrentAbstract" xlink:label="loc_us-gaap_LiabilitiesCurrentAbstract_13A27370C9FC3400BE5AD216312C3891" xlink:type="locator" />
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    <link:label id="lab_us-gaap_AccountsPayableCurrent_D01B95081EC767D5CDD6D216312C2848_verboseLabel_en-US" xlink:label="lab_us-gaap_AccountsPayableCurrent_D01B95081EC767D5CDD6D216312C2848" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Accounts payable</link:label>
    <link:label id="lab_us-gaap_AccountsPayableCurrent_D01B95081EC767D5CDD6D216312C2848_label_en-US" xlink:label="lab_us-gaap_AccountsPayableCurrent_D01B95081EC767D5CDD6D216312C2848" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Accounts Payable, Current</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_AccountsPayableCurrent" xlink:label="loc_us-gaap_AccountsPayableCurrent_D01B95081EC767D5CDD6D216312C2848" xlink:type="locator" />
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    <link:label id="lab_us-gaap_AccruedLiabilitiesCurrent_7C6159B4C2FEFECC4BF8D216312D23CD_verboseLabel_en-US" xlink:label="lab_us-gaap_AccruedLiabilitiesCurrent_7C6159B4C2FEFECC4BF8D216312D23CD" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Accrued liabilities (note 12)</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_AccruedLiabilitiesCurrent" xlink:label="loc_us-gaap_AccruedLiabilitiesCurrent_7C6159B4C2FEFECC4BF8D216312D23CD" xlink:type="locator" />
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    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_BillingsInExcessOfCostCurrent" xlink:label="loc_us-gaap_BillingsInExcessOfCostCurrent_465D3080E4BF63FF1B3AD216312DBC39" xlink:type="locator" />
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    <link:label id="lab_us-gaap_CapitalLeaseObligationsCurrent_7DAE3606FB3762E1F633D216312D9843_terseLabel_en-US" xlink:label="lab_us-gaap_CapitalLeaseObligationsCurrent_7DAE3606FB3762E1F633D216312D9843" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Current portion of capital lease obligations (note 14)</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_CapitalLeaseObligationsCurrent" xlink:label="loc_us-gaap_CapitalLeaseObligationsCurrent_7DAE3606FB3762E1F633D216312D9843" xlink:type="locator" />
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    <link:label id="lab_us-gaap_LiabilitiesCurrent_2FB62C86ECE65A587B29D216312D8383_totalLabel_en-US" xlink:label="lab_us-gaap_LiabilitiesCurrent_2FB62C86ECE65A587B29D216312D8383" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Total current liabilities</link:label>
    <link:label id="lab_us-gaap_LiabilitiesCurrent_2FB62C86ECE65A587B29D216312D8383_label_en-US" xlink:label="lab_us-gaap_LiabilitiesCurrent_2FB62C86ECE65A587B29D216312D8383" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Liabilities, Current</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_LiabilitiesCurrent" xlink:label="loc_us-gaap_LiabilitiesCurrent_2FB62C86ECE65A587B29D216312D8383" xlink:type="locator" />
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    <link:label id="lab_us-gaap_LongTermDebtNoncurrent_3E9FF4D3081B6922DF9FD216312DF4AE_verboseLabel_en-US" xlink:label="lab_us-gaap_LongTermDebtNoncurrent_3E9FF4D3081B6922DF9FD216312DF4AE" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Long term debt (note 13(a))</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_LongTermDebtNoncurrent" xlink:label="loc_us-gaap_LongTermDebtNoncurrent_3E9FF4D3081B6922DF9FD216312DF4AE" xlink:type="locator" />
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    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_OtherLiabilitiesNoncurrent" xlink:label="loc_us-gaap_OtherLiabilitiesNoncurrent_02725AB5F8E2C8D206A8D216312D9041" xlink:type="locator" />
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    <link:label id="lab_us-gaap_Liabilities_090F5391687BE0461037D216312D3DAF_label_en-US" xlink:label="lab_us-gaap_Liabilities_090F5391687BE0461037D216312D3DAF" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Liabilities</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2015/elts/us-gaap-2015-01-31.xsd#us-gaap_Liabilities" xlink:label="loc_us-gaap_Liabilities_090F5391687BE0461037D216312D3DAF" xlink:type="locator" />
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    <link:label id="lab_noa_LongLivedAssetsHeldForSalePolicyPolicyTextBlock_B0D29FD6E071AE78C0A29F06DACD1562_terseLabel_en-US" xlink:label="lab_noa_LongLivedAssetsHeldForSalePolicyPolicyTextBlock_B0D29FD6E071AE78C0A29F06DACD1562" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Assets held for sale</link:label>
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