Plans that could see Merthyr Tydfil become Wales’ St Moritz are facing the cold shoulder after being recommended for refusal.

The location, visual and ecological impact of the scheme, which would include the UK’s longest ski slope at 500m (1,640 ft), have raised concerns among Merthyr Tydfil council officers.

The development, called Rhydycar West, would include a snow centre, a tropical waterpark and an activity centre, all indoors, while there would be an activity area outdoors.

There would also be as many as 418 hotel rooms, up to 30 lodges and potentially 830 parking spaces.

The application, from Marvel Ltd, covers land to the south-west of Merthyr Tydfil’s A470/A4102 roundabout.

Plans for the attraction have previously been endorsed by GB Snowsport and Snowsport Cymru Wales, who said they wanted it to be an Olympic and elite athlete training hub.

Historically it has been used for industrial activities with the remains of mine workings, spoil tips, canal and railway features still on site, according to the planning report.

There are scheduled ancient monuments and a Grade II listed building on the site, which is part of the Merthyr Tydfil landscape of outstanding historic interest.

The site includes the Cwmglo and Glyndyrus site of special scientific interest, the Rhydycar West site of importance for nature conservation, ancient woodland and woods covered by tree preservation orders.

A network of public rights of way crosses the site and into the surrounding area.

A farm has been proposed as off-site compensation for ecological loss that cannot be provided within the site.

In total there have been 141 letters in support of the application and 23 objections sent to the council.

Supporters pointed to economic benefits including job creation, training opportunities and more tourists.

They highlighted supply chain benefits and the possibility of the attraction driving further investment to the area.

Opponents said the application was contrary to planning policy, would badly affect the landscape and historic designations and could damage the canal and affect public rights of way.

There were also worries about congestion, pollution, noise, litter, anti-social behaviour, and destruction of natural habitat.

The planning report outlined concern with the proposed development due to its planned location, sustainability, scale, impact on the view and ecology and the conflicts with national and local planning policies.

The Welsh government’s Design Commission for Wales issued a report and said it was “unable to support the proposal”, setting out “significant and fundamental concerns”.

The council report said: “On balance, the potential economic and social benefits including employment creation, significant private investment, and enhanced leisure facilities would not outweigh the harm identified to the important ecological and landscape value of the site.”

The application is due to go before the council’s planning committee on 12 March.