Move or Remove Callouts on the left or right sidebar in magento

<reference name="left">
<block name="left.permanent.callout" template="callouts/left_col.phtml" type="core/template">
<action method="setImgSrc"><src>images/media/col_left_callout.jpg</src></action>
<action method="setImgAlt" module="catalog" translate="alt"><alt>Our customer service is available 24/7. Call us at (555) 555-0123.</alt></action>
<action method="setLinkUrl"><url>checkout/cart</url></action>
</block>
</reference>