how to close tcp close_wait connection by hand in mac

When I using this command in Mac OS terminal:

netstat -n| awk '/^tcp/ {++S[$NF]} END {for(a in S) print a, S[a]}'

I found too many close_wait connection and I want to clear by hand.

SYN_SENT 13
LAST_ACK 7
CLOSE_WAIT 3481
TIME_WAIT 14
ESTABLISHED 2760

Is it possible? How to configure to close automatic in Mac?