; and of which $1,500,000 is for paid apprenticeships for participants in the Human Exploitation Rescue Operative Corps: Provided , That not to exceed $11,475 shall be for official reception and representation expenses: Provided further , That not to exceed $10,000,000 shall be available until expended for conducting special operations under section 3131 of the Customs Enforcement Act of 1986 ( 19 U.S.C. 2081 ): Provided further , That not to exceed $2,000,000 shall be for awards of compensation to informants, to be accounted for solely under the certificate of the Secretary of Homeland Security: Provided further , That not to exceed $11,216,000 shall be available to fund or reimburse other Federal agencies for the costs associated with the care, maintenance, and repatriation of smuggled aliens unlawfully present in the United States. Procurement, construction, and improvements For necessary expenses of U.S. Immigration and Customs Enforcement for procurement, construction, and improvements, $70,431,000, to remain available until September 30, 2021. Transportation security administration Operations and support For necessary expenses of the Transportation Security Administration for operations and support, $7,167,778,000, to remain available until September 30, 2020: Provided , That not to exceed $7,650 shall be for official reception and representation expenses: Provided further , That security service fees authorized under section 44940 of title 49, United States Code, shall be credited to this appropriation as offsetting collections and shall be available only for aviation security: Provided further , That the sum appropriated under this heading from the general fund shall be reduced on a dollar-for-dollar basis as such offsetting collections are received during fiscal year 2019 so as to result in a final fiscal year appropriation from the general fund estimated at not more than $4,497,778,000. Procurement, construction, and improvements For necessary expenses of the Transportation Security Administration for