Can the Health and Safety policy be combined with the Environmental policy?

First, yes you can have integrated health, safety, and environmental policy. Second, whether or not that is the best approach for your organization, will depend on the effective integration of the two systems. Third, in theory, I always try to integrate management systems because people in an organization do not work according to each management system, in particular, they simply do their work.  The following material will provide you with information about implementing integrated systems:

• How to implement integrated management systems - https://advisera.com/articles/how-to-implement-integrated-management-systems/
• Free webinar – How to integrate ISO 9001:2015 and ISO 14001:2015 - https://advisera.com/9001academy/webinar/how-to-integrate-iso-90012015-and-iso-140012015-free-webinar-on-demand/
• ISO 9001, ISO 14001 and ISO 45001 Integrated Documentation Toolkit - https://advisera.com/9001academy/iso-9001-iso-14001-iso-45001-integrated-documentation-toolkit/
• book - THE ISO 14001:2015 COMPANION – A A Straightforward Guide to Implementing an EMS in a Small Business - https://advisera.com/books/the-iso-14001-2015-companion/