diff --git a/megatron/rl/parallel_utils.py b/megatron/rl/parallel_utils.py
index da4ee8aa4cf..3f169d6e2ad 100644
--- a/megatron/rl/parallel_utils.py
+++ b/megatron/rl/parallel_utils.py
@@ -6,7 +6,12 @@
 
 from typing import Optional
 
-import torch.distributed as dist
+try:
+    import torch.distributed as dist
+    HAS_TORCH_DISTRIBUTED = True
+except ImportError:
+    HAS_TORCH_DISTRIBUTED = False
+    dist = None
 
 from megatron.core import mpu
 from megatron.core.hyper_comm_grid import HyperCommGrid
@@ -71,6 +76,9 @@ def build_inference_pg_collection(
         f"World size ({world_size}) must be divisible by expt_tp*ep*pp ({expt_tp_size * ep_size * pp_size})"
     )
 
+    if not HAS_TORCH_DISTRIBUTED:
+        raise ImportError("torch.distributed is required for building inference process groups.")
+
     rank = dist.get_rank()
 
     # ====================
diff --git a/megatron/rl/rl_utils.py b/megatron/rl/rl_utils.py
index 8f145bd5a4c..7b0ab7f5031 100644
--- a/megatron/rl/rl_utils.py
+++ b/megatron/rl/rl_utils.py
@@ -571,9 +571,15 @@ def get_environment_rollouts(
                     rollouts = [[None for _ in range(samples_per_group)] for _ in range(n_prompts)]
 
         with nvtx_range("sync-rollouts"):
-            # Wait for Rollouts to be collected
-            # TODO(jbarker): double check why this isn't causing rank 0 memory allocations
-            torch.distributed.broadcast_object_list(rollouts, src=0)
+            # Wait for Rollouts to be collected. Broadcast in small chunks to avoid
+            # pickling the entire `rollouts` list at once (which can cause large
+            # temporary allocations on rank 0).
+            for i in range(n_prompts):
+                group = rollouts[i] if rank == 0 else None
+                obj_list = [group]
+                torch.distributed.broadcast_object_list(obj_list, src=0)
+                if rank != 0:
+                    rollouts[i] = obj_list[0]
         logger.debug(f"Got rollouts on rank {rank}")
 
     if args.rl_offload_optimizer_during_inference: